ETH Price: $2,682.50 (+4.49%)

Transaction Decoder

Block:
16946430 at Mar-31-2023 09:55:23 AM +UTC
Transaction Fee:
0.003073363097656068 ETH $8.24
Gas Used:
133,938 Gas / 22.946162386 Gwei

Emitted Events:

194 AppProxyUpgradeable.0x96a25c8ce0baabc1fdefd93e9ed25d8e092a3332f3aa9a41722b5697231d1d1a( 0x96a25c8ce0baabc1fdefd93e9ed25d8e092a3332f3aa9a41722b5697231d1d1a, 0x00000000000000000000000067054183db455d74839d1ea11f7e497350f64c71, 000000000000000000000000000000000000000000000000002386f26fc10000, 000000000000000000000000fe2da24c0d0ecdcc4753ef7d1ed637b75b7b6c47 )
195 AppProxyUpgradeable.0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef( 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef, 0x0000000000000000000000000000000000000000000000000000000000000000, 0x00000000000000000000000067054183db455d74839d1ea11f7e497350f64c71, 000000000000000000000000000000000000000000000000002386f26fc0ffff )
196 AppProxyUpgradeable.0x9d9c909296d9c674451c0c24f02cb64981eb3b727f99865939192f880a755dcb( 0x9d9c909296d9c674451c0c24f02cb64981eb3b727f99865939192f880a755dcb, 0x0000000000000000000000000000000000000000000000000000000000000000, 0x00000000000000000000000067054183db455d74839d1ea11f7e497350f64c71, 000000000000000000000000000000000000000000000000001fcfe438d5c233 )
197 AppProxyUpgradeable.0x9d9c909296d9c674451c0c24f02cb64981eb3b727f99865939192f880a755dcb( 0x9d9c909296d9c674451c0c24f02cb64981eb3b727f99865939192f880a755dcb, 0x00000000000000000000000067054183db455d74839d1ea11f7e497350f64c71, 0x00000000000000000000000007f5813f95462da339f57e401e5cc12a7f602e50, 000000000000000000000000000000000000000000000000001fcfe438d5c233 )
198 AppProxyUpgradeable.0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef( 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef, 0x00000000000000000000000067054183db455d74839d1ea11f7e497350f64c71, 0x00000000000000000000000007f5813f95462da339f57e401e5cc12a7f602e50, 000000000000000000000000000000000000000000000000002386f26fc0ffff )

Account State Difference:

  Address   Before After State Difference Code
0x07F5813f...A7F602e50
0.110313001397283209 Eth
Nonce: 39
0.097239638299627141 Eth
Nonce: 40
0.013073363097656068
(Fee Recipient: 0x8E...a97)
93.633548734059230461 Eth93.633562127859230461 Eth0.0000133938
0xae7ab965...312D7fE84 4.711968346180814306 Eth4.721968346180814306 Eth0.01

Execution Trace

ETH 0.01 StakingAggregator.depositToLido( maxFeeRate=0 )
  • ETH 0.01 AppProxyUpgradeable.a1903eab( )
    • KernelProxy.be00bbd8( )
      • Kernel.getApp( _namespace=F1F3EB40F5BC1AD1344716CED8B8A0431D840B5783AEA1FD01786BC26F35AC0F, _appId=3CA7C3E38968823CCB4C78EA688DF41356F182AE1D159E4EE608D30D68CEF320 ) => ( 0x47EbaB13B806773ec2A2d16873e2dF770D130b50 )
      • ETH 0.01 Lido.submit( _referral=0xfe2da24c0D0ECdcC4753ef7D1eD637b75B7B6C47 ) => ( 8954303391056435 )
      • AppProxyUpgradeable.8fcb4e5b( )
        • KernelProxy.be00bbd8( )
          • Kernel.getApp( _namespace=F1F3EB40F5BC1AD1344716CED8B8A0431D840B5783AEA1FD01786BC26F35AC0F, _appId=3CA7C3E38968823CCB4C78EA688DF41356F182AE1D159E4EE608D30D68CEF320 ) => ( 0x47EbaB13B806773ec2A2d16873e2dF770D130b50 )
          • Lido.transferShares( _recipient=0x07F5813f95462Da339F57e401e5cc12A7F602e50, _sharesAmount=8954303391056435 ) => ( 9999999999999999 )
            File 1 of 5: StakingAggregator
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
            pragma solidity ^0.8.0;
            import "../utils/Context.sol";
            /**
             * @dev Contract module which provides a basic access control mechanism, where
             * there is an account (an owner) that can be granted exclusive access to
             * specific functions.
             *
             * By default, the owner account will be the one that deploys the contract. This
             * can later be changed with {transferOwnership}.
             *
             * This module is used through inheritance. It will make available the modifier
             * `onlyOwner`, which can be applied to your functions to restrict their use to
             * the owner.
             */
            abstract contract Ownable is Context {
                address private _owner;
                event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                /**
                 * @dev Initializes the contract setting the deployer as the initial owner.
                 */
                constructor() {
                    _transferOwnership(_msgSender());
                }
                /**
                 * @dev Throws if called by any account other than the owner.
                 */
                modifier onlyOwner() {
                    _checkOwner();
                    _;
                }
                /**
                 * @dev Returns the address of the current owner.
                 */
                function owner() public view virtual returns (address) {
                    return _owner;
                }
                /**
                 * @dev Throws if the sender is not the owner.
                 */
                function _checkOwner() internal view virtual {
                    require(owner() == _msgSender(), "Ownable: caller is not the owner");
                }
                /**
                 * @dev Leaves the contract without owner. It will not be possible to call
                 * `onlyOwner` functions anymore. Can only be called by the current owner.
                 *
                 * NOTE: Renouncing ownership will leave the contract without an owner,
                 * thereby removing any functionality that is only available to the owner.
                 */
                function renounceOwnership() public virtual onlyOwner {
                    _transferOwnership(address(0));
                }
                /**
                 * @dev Transfers ownership of the contract to a new account (`newOwner`).
                 * Can only be called by the current owner.
                 */
                function transferOwnership(address newOwner) public virtual onlyOwner {
                    require(newOwner != address(0), "Ownable: new owner is the zero address");
                    _transferOwnership(newOwner);
                }
                /**
                 * @dev Transfers ownership of the contract to a new account (`newOwner`).
                 * Internal function without access restriction.
                 */
                function _transferOwnership(address newOwner) internal virtual {
                    address oldOwner = _owner;
                    _owner = newOwner;
                    emit OwnershipTransferred(oldOwner, newOwner);
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts (last updated v4.8.0) (access/Ownable2Step.sol)
            pragma solidity ^0.8.0;
            import "./Ownable.sol";
            /**
             * @dev Contract module which provides access control mechanism, where
             * there is an account (an owner) that can be granted exclusive access to
             * specific functions.
             *
             * By default, the owner account will be the one that deploys the contract. This
             * can later be changed with {transferOwnership} and {acceptOwnership}.
             *
             * This module is used through inheritance. It will make available all functions
             * from parent (Ownable).
             */
            abstract contract Ownable2Step is Ownable {
                address private _pendingOwner;
                event OwnershipTransferStarted(address indexed previousOwner, address indexed newOwner);
                /**
                 * @dev Returns the address of the pending owner.
                 */
                function pendingOwner() public view virtual returns (address) {
                    return _pendingOwner;
                }
                /**
                 * @dev Starts the ownership transfer of the contract to a new account. Replaces the pending transfer if there is one.
                 * Can only be called by the current owner.
                 */
                function transferOwnership(address newOwner) public virtual override onlyOwner {
                    _pendingOwner = newOwner;
                    emit OwnershipTransferStarted(owner(), newOwner);
                }
                /**
                 * @dev Transfers ownership of the contract to a new account (`newOwner`) and deletes any pending owner.
                 * Internal function without access restriction.
                 */
                function _transferOwnership(address newOwner) internal virtual override {
                    delete _pendingOwner;
                    super._transferOwnership(newOwner);
                }
                /**
                 * @dev The new owner accepts the ownership transfer.
                 */
                function acceptOwnership() external {
                    address sender = _msgSender();
                    require(pendingOwner() == sender, "Ownable2Step: caller is not the new owner");
                    _transferOwnership(sender);
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol)
            pragma solidity ^0.8.0;
            import "../utils/Context.sol";
            /**
             * @dev Contract module which allows children to implement an emergency stop
             * mechanism that can be triggered by an authorized account.
             *
             * This module is used through inheritance. It will make available the
             * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
             * the functions of your contract. Note that they will not be pausable by
             * simply including this module, only once the modifiers are put in place.
             */
            abstract contract Pausable is Context {
                /**
                 * @dev Emitted when the pause is triggered by `account`.
                 */
                event Paused(address account);
                /**
                 * @dev Emitted when the pause is lifted by `account`.
                 */
                event Unpaused(address account);
                bool private _paused;
                /**
                 * @dev Initializes the contract in unpaused state.
                 */
                constructor() {
                    _paused = false;
                }
                /**
                 * @dev Modifier to make a function callable only when the contract is not paused.
                 *
                 * Requirements:
                 *
                 * - The contract must not be paused.
                 */
                modifier whenNotPaused() {
                    _requireNotPaused();
                    _;
                }
                /**
                 * @dev Modifier to make a function callable only when the contract is paused.
                 *
                 * Requirements:
                 *
                 * - The contract must be paused.
                 */
                modifier whenPaused() {
                    _requirePaused();
                    _;
                }
                /**
                 * @dev Returns true if the contract is paused, and false otherwise.
                 */
                function paused() public view virtual returns (bool) {
                    return _paused;
                }
                /**
                 * @dev Throws if the contract is paused.
                 */
                function _requireNotPaused() internal view virtual {
                    require(!paused(), "Pausable: paused");
                }
                /**
                 * @dev Throws if the contract is not paused.
                 */
                function _requirePaused() internal view virtual {
                    require(paused(), "Pausable: not paused");
                }
                /**
                 * @dev Triggers stopped state.
                 *
                 * Requirements:
                 *
                 * - The contract must not be paused.
                 */
                function _pause() internal virtual whenNotPaused {
                    _paused = true;
                    emit Paused(_msgSender());
                }
                /**
                 * @dev Returns to normal state.
                 *
                 * Requirements:
                 *
                 * - The contract must be paused.
                 */
                function _unpause() internal virtual whenPaused {
                    _paused = false;
                    emit Unpaused(_msgSender());
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts (last updated v4.8.0) (security/ReentrancyGuard.sol)
            pragma solidity ^0.8.0;
            /**
             * @dev Contract module that helps prevent reentrant calls to a function.
             *
             * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
             * available, which can be applied to functions to make sure there are no nested
             * (reentrant) calls to them.
             *
             * Note that because there is a single `nonReentrant` guard, functions marked as
             * `nonReentrant` may not call one another. This can be worked around by making
             * those functions `private`, and then adding `external` `nonReentrant` entry
             * points to them.
             *
             * TIP: If you would like to learn more about reentrancy and alternative ways
             * to protect against it, check out our blog post
             * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
             */
            abstract contract ReentrancyGuard {
                // Booleans are more expensive than uint256 or any type that takes up a full
                // word because each write operation emits an extra SLOAD to first read the
                // slot's contents, replace the bits taken up by the boolean, and then write
                // back. This is the compiler's defense against contract upgrades and
                // pointer aliasing, and it cannot be disabled.
                // The values being non-zero value makes deployment a bit more expensive,
                // but in exchange the refund on every call to nonReentrant will be lower in
                // amount. Since refunds are capped to a percentage of the total
                // transaction's gas, it is best to keep them low in cases like this one, to
                // increase the likelihood of the full refund coming into effect.
                uint256 private constant _NOT_ENTERED = 1;
                uint256 private constant _ENTERED = 2;
                uint256 private _status;
                constructor() {
                    _status = _NOT_ENTERED;
                }
                /**
                 * @dev Prevents a contract from calling itself, directly or indirectly.
                 * Calling a `nonReentrant` function from another `nonReentrant`
                 * function is not supported. It is possible to prevent this from happening
                 * by making the `nonReentrant` function external, and making it call a
                 * `private` function that does the actual work.
                 */
                modifier nonReentrant() {
                    _nonReentrantBefore();
                    _;
                    _nonReentrantAfter();
                }
                function _nonReentrantBefore() private {
                    // On the first call to nonReentrant, _status will be _NOT_ENTERED
                    require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
                    // Any calls to nonReentrant after this point will fail
                    _status = _ENTERED;
                }
                function _nonReentrantAfter() private {
                    // By storing the original value once again, a refund is triggered (see
                    // https://eips.ethereum.org/EIPS/eip-2200)
                    _status = _NOT_ENTERED;
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/ERC20.sol)
            pragma solidity ^0.8.0;
            import "./IERC20.sol";
            import "./extensions/IERC20Metadata.sol";
            import "../../utils/Context.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.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
             * to implement supply mechanisms].
             *
             * We have followed general OpenZeppelin Contracts guidelines: functions revert
             * instead 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, IERC20Metadata {
                mapping(address => uint256) private _balances;
                mapping(address => mapping(address => uint256)) private _allowances;
                uint256 private _totalSupply;
                string private _name;
                string private _symbol;
                /**
                 * @dev Sets the values for {name} and {symbol}.
                 *
                 * The default value of {decimals} is 18. To select a different value for
                 * {decimals} you should overload it.
                 *
                 * All two of these values are immutable: they can only be set once during
                 * construction.
                 */
                constructor(string memory name_, string memory symbol_) {
                    _name = name_;
                    _symbol = symbol_;
                }
                /**
                 * @dev Returns the name of the token.
                 */
                function name() public view virtual override returns (string memory) {
                    return _name;
                }
                /**
                 * @dev Returns the symbol of the token, usually a shorter version of the
                 * name.
                 */
                function symbol() public view virtual override 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 this function is
                 * overridden;
                 *
                 * 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 override returns (uint8) {
                    return 18;
                }
                /**
                 * @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:
                 *
                 * - `to` cannot be the zero address.
                 * - the caller must have a balance of at least `amount`.
                 */
                function transfer(address to, uint256 amount) public virtual override returns (bool) {
                    address owner = _msgSender();
                    _transfer(owner, to, 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}.
                 *
                 * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
                 * `transferFrom`. This is semantically equivalent to an infinite approval.
                 *
                 * Requirements:
                 *
                 * - `spender` cannot be the zero address.
                 */
                function approve(address spender, uint256 amount) public virtual override returns (bool) {
                    address owner = _msgSender();
                    _approve(owner, 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}.
                 *
                 * NOTE: Does not update the allowance if the current allowance
                 * is the maximum `uint256`.
                 *
                 * Requirements:
                 *
                 * - `from` and `to` cannot be the zero address.
                 * - `from` must have a balance of at least `amount`.
                 * - the caller must have allowance for ``from``'s tokens of at least
                 * `amount`.
                 */
                function transferFrom(
                    address from,
                    address to,
                    uint256 amount
                ) public virtual override returns (bool) {
                    address spender = _msgSender();
                    _spendAllowance(from, spender, amount);
                    _transfer(from, to, amount);
                    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) {
                    address owner = _msgSender();
                    _approve(owner, spender, allowance(owner, spender) + 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) {
                    address owner = _msgSender();
                    uint256 currentAllowance = allowance(owner, spender);
                    require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
                    unchecked {
                        _approve(owner, spender, currentAllowance - subtractedValue);
                    }
                    return true;
                }
                /**
                 * @dev Moves `amount` of tokens from `from` to `to`.
                 *
                 * This 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:
                 *
                 * - `from` cannot be the zero address.
                 * - `to` cannot be the zero address.
                 * - `from` must have a balance of at least `amount`.
                 */
                function _transfer(
                    address from,
                    address to,
                    uint256 amount
                ) internal virtual {
                    require(from != address(0), "ERC20: transfer from the zero address");
                    require(to != address(0), "ERC20: transfer to the zero address");
                    _beforeTokenTransfer(from, to, amount);
                    uint256 fromBalance = _balances[from];
                    require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
                    unchecked {
                        _balances[from] = fromBalance - amount;
                        // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
                        // decrementing then incrementing.
                        _balances[to] += amount;
                    }
                    emit Transfer(from, to, amount);
                    _afterTokenTransfer(from, to, 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:
                 *
                 * - `account` 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 += amount;
                    unchecked {
                        // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
                        _balances[account] += amount;
                    }
                    emit Transfer(address(0), account, amount);
                    _afterTokenTransfer(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);
                    uint256 accountBalance = _balances[account];
                    require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
                    unchecked {
                        _balances[account] = accountBalance - amount;
                        // Overflow not possible: amount <= accountBalance <= totalSupply.
                        _totalSupply -= amount;
                    }
                    emit Transfer(account, address(0), amount);
                    _afterTokenTransfer(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 Updates `owner` s allowance for `spender` based on spent `amount`.
                 *
                 * Does not update the allowance amount in case of infinite allowance.
                 * Revert if not enough allowance is available.
                 *
                 * Might emit an {Approval} event.
                 */
                function _spendAllowance(
                    address owner,
                    address spender,
                    uint256 amount
                ) internal virtual {
                    uint256 currentAllowance = allowance(owner, spender);
                    if (currentAllowance != type(uint256).max) {
                        require(currentAllowance >= amount, "ERC20: insufficient allowance");
                        unchecked {
                            _approve(owner, spender, currentAllowance - amount);
                        }
                    }
                }
                /**
                 * @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 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 {}
                /**
                 * @dev Hook that is called after any transfer of tokens. This includes
                 * minting and burning.
                 *
                 * Calling conditions:
                 *
                 * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
                 * has been transferred to `to`.
                 * - when `from` is zero, `amount` tokens have been minted for `to`.
                 * - when `to` is zero, `amount` of ``from``'s tokens have been 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 _afterTokenTransfer(
                    address from,
                    address to,
                    uint256 amount
                ) internal virtual {}
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/extensions/ERC20Burnable.sol)
            pragma solidity ^0.8.0;
            import "../ERC20.sol";
            import "../../../utils/Context.sol";
            /**
             * @dev Extension of {ERC20} that allows token holders to destroy both their own
             * tokens and those that they have an allowance for, in a way that can be
             * recognized off-chain (via event analysis).
             */
            abstract contract ERC20Burnable is Context, ERC20 {
                /**
                 * @dev Destroys `amount` tokens from the caller.
                 *
                 * See {ERC20-_burn}.
                 */
                function burn(uint256 amount) public virtual {
                    _burn(_msgSender(), amount);
                }
                /**
                 * @dev Destroys `amount` tokens from `account`, deducting from the caller's
                 * allowance.
                 *
                 * See {ERC20-_burn} and {ERC20-allowance}.
                 *
                 * Requirements:
                 *
                 * - the caller must have allowance for ``accounts``'s tokens of at least
                 * `amount`.
                 */
                function burnFrom(address account, uint256 amount) public virtual {
                    _spendAllowance(account, _msgSender(), amount);
                    _burn(account, amount);
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
            pragma solidity ^0.8.0;
            import "../IERC20.sol";
            /**
             * @dev Interface for the optional metadata functions from the ERC20 standard.
             *
             * _Available since v4.1._
             */
            interface IERC20Metadata is IERC20 {
                /**
                 * @dev Returns the name of the token.
                 */
                function name() external view returns (string memory);
                /**
                 * @dev Returns the symbol of the token.
                 */
                function symbol() external view returns (string memory);
                /**
                 * @dev Returns the decimals places of the token.
                 */
                function decimals() external view returns (uint8);
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
            pragma solidity ^0.8.0;
            /**
             * @dev Interface of the ERC20 standard as defined in the EIP.
             */
            interface IERC20 {
                /**
                 * @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);
                /**
                 * @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 `to`.
                 *
                 * Returns a boolean value indicating whether the operation succeeded.
                 *
                 * Emits a {Transfer} event.
                 */
                function transfer(address to, 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 `from` to `to` 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 from,
                    address to,
                    uint256 amount
                ) external returns (bool);
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)
            pragma solidity ^0.8.1;
            /**
             * @dev Collection of functions related to the address type
             */
            library Address {
                /**
                 * @dev Returns true if `account` is a contract.
                 *
                 * [IMPORTANT]
                 * ====
                 * It is unsafe to assume that an address for which this function returns
                 * false is an externally-owned account (EOA) and not a contract.
                 *
                 * Among others, `isContract` will return false for the following
                 * types of addresses:
                 *
                 *  - an externally-owned account
                 *  - a contract in construction
                 *  - an address where a contract will be created
                 *  - an address where a contract lived, but was destroyed
                 * ====
                 *
                 * [IMPORTANT]
                 * ====
                 * You shouldn't rely on `isContract` to protect against flash loan attacks!
                 *
                 * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
                 * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
                 * constructor.
                 * ====
                 */
                function isContract(address account) internal view returns (bool) {
                    // This method relies on extcodesize/address.code.length, which returns 0
                    // for contracts in construction, since the code is only stored at the end
                    // of the constructor execution.
                    return account.code.length > 0;
                }
                /**
                 * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                 * `recipient`, forwarding all available gas and reverting on errors.
                 *
                 * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                 * of certain opcodes, possibly making contracts go over the 2300 gas limit
                 * imposed by `transfer`, making them unable to receive funds via
                 * `transfer`. {sendValue} removes this limitation.
                 *
                 * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                 *
                 * IMPORTANT: because control is transferred to `recipient`, care must be
                 * taken to not create reentrancy vulnerabilities. Consider using
                 * {ReentrancyGuard} or the
                 * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                 */
                function sendValue(address payable recipient, uint256 amount) internal {
                    require(address(this).balance >= amount, "Address: insufficient balance");
                    (bool success, ) = recipient.call{value: amount}("");
                    require(success, "Address: unable to send value, recipient may have reverted");
                }
                /**
                 * @dev Performs a Solidity function call using a low level `call`. A
                 * plain `call` is an unsafe replacement for a function call: use this
                 * function instead.
                 *
                 * If `target` reverts with a revert reason, it is bubbled up by this
                 * function (like regular Solidity function calls).
                 *
                 * Returns the raw returned data. To convert to the expected return value,
                 * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                 *
                 * Requirements:
                 *
                 * - `target` must be a contract.
                 * - calling `target` with `data` must not revert.
                 *
                 * _Available since v3.1._
                 */
                function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                    return functionCallWithValue(target, data, 0, "Address: low-level call failed");
                }
                /**
                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                 * `errorMessage` as a fallback revert reason when `target` reverts.
                 *
                 * _Available since v3.1._
                 */
                function functionCall(
                    address target,
                    bytes memory data,
                    string memory errorMessage
                ) internal returns (bytes memory) {
                    return functionCallWithValue(target, data, 0, errorMessage);
                }
                /**
                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                 * but also transferring `value` wei to `target`.
                 *
                 * Requirements:
                 *
                 * - the calling contract must have an ETH balance of at least `value`.
                 * - the called Solidity function must be `payable`.
                 *
                 * _Available since v3.1._
                 */
                function functionCallWithValue(
                    address target,
                    bytes memory data,
                    uint256 value
                ) internal returns (bytes memory) {
                    return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                }
                /**
                 * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                 * with `errorMessage` as a fallback revert reason when `target` reverts.
                 *
                 * _Available since v3.1._
                 */
                function functionCallWithValue(
                    address target,
                    bytes memory data,
                    uint256 value,
                    string memory errorMessage
                ) internal returns (bytes memory) {
                    require(address(this).balance >= value, "Address: insufficient balance for call");
                    (bool success, bytes memory returndata) = target.call{value: value}(data);
                    return verifyCallResultFromTarget(target, success, returndata, errorMessage);
                }
                /**
                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                 * but performing a static call.
                 *
                 * _Available since v3.3._
                 */
                function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                    return functionStaticCall(target, data, "Address: low-level static call failed");
                }
                /**
                 * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                 * but performing a static call.
                 *
                 * _Available since v3.3._
                 */
                function functionStaticCall(
                    address target,
                    bytes memory data,
                    string memory errorMessage
                ) internal view returns (bytes memory) {
                    (bool success, bytes memory returndata) = target.staticcall(data);
                    return verifyCallResultFromTarget(target, success, returndata, errorMessage);
                }
                /**
                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                 * but performing a delegate call.
                 *
                 * _Available since v3.4._
                 */
                function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                    return functionDelegateCall(target, data, "Address: low-level delegate call failed");
                }
                /**
                 * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                 * but performing a delegate call.
                 *
                 * _Available since v3.4._
                 */
                function functionDelegateCall(
                    address target,
                    bytes memory data,
                    string memory errorMessage
                ) internal returns (bytes memory) {
                    (bool success, bytes memory returndata) = target.delegatecall(data);
                    return verifyCallResultFromTarget(target, success, returndata, errorMessage);
                }
                /**
                 * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
                 * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
                 *
                 * _Available since v4.8._
                 */
                function verifyCallResultFromTarget(
                    address target,
                    bool success,
                    bytes memory returndata,
                    string memory errorMessage
                ) internal view returns (bytes memory) {
                    if (success) {
                        if (returndata.length == 0) {
                            // only check isContract if the call was successful and the return data is empty
                            // otherwise we already know that it was a contract
                            require(isContract(target), "Address: call to non-contract");
                        }
                        return returndata;
                    } else {
                        _revert(returndata, errorMessage);
                    }
                }
                /**
                 * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
                 * revert reason or using the provided one.
                 *
                 * _Available since v4.3._
                 */
                function verifyCallResult(
                    bool success,
                    bytes memory returndata,
                    string memory errorMessage
                ) internal pure returns (bytes memory) {
                    if (success) {
                        return returndata;
                    } else {
                        _revert(returndata, errorMessage);
                    }
                }
                function _revert(bytes memory returndata, string memory errorMessage) private pure {
                    // Look for revert reason and bubble it up if present
                    if (returndata.length > 0) {
                        // The easiest way to bubble the revert reason is using memory via assembly
                        /// @solidity memory-safe-assembly
                        assembly {
                            let returndata_size := mload(returndata)
                            revert(add(32, returndata), returndata_size)
                        }
                    } else {
                        revert(errorMessage);
                    }
                }
            }
            // SPDX-License-Identifier: MIT
            // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
            pragma solidity ^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 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) {
                    return msg.sender;
                }
                function _msgData() internal view virtual returns (bytes calldata) {
                    return msg.data;
                }
            }
            // SPDX-License-Identifier: NONE
            pragma solidity 0.8.17;
            import "../interfaces/RocketStorage.sol";
            import "../interfaces/RocketDepositPool.sol";
            import "../interfaces/RocketTokenRETH.sol";
            import "../interfaces/RocketDAOProtocolSettingsDepositInterface.sol";
            import "../interfaces/RocketVault.sol";
            import "../interfaces/ILido.sol";
            import "@openzeppelin/contracts/access/Ownable2Step.sol";
            import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
            import "@openzeppelin/contracts/security/Pausable.sol";
            import "@openzeppelin/contracts/utils/Address.sol";
            import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
            /// @title A staking aggregation contract for RocketPool and Lido
            /// @author Jack Clancy - Consensys
            contract StakingAggregator is Ownable2Step, ReentrancyGuard, Pausable {
                using Address for address payable;
                RocketStorageInterface immutable rocketStorage;
                LidoInterface public immutable lidoProxyAddress;
                address public immutable lidoReferralAddress;
                uint256 public fee; // fee in 1/10th of bps
                uint256 public constant MAX_FEE = 2000; // maxFee in 1/10th of bps - 2% or 200bps
                uint256 public constant FEE_BASE = 100000;
                address payable public feesRecipient;
                constructor(
                    address _owner,
                    address _lidoReferralAddress,
                    RocketStorageInterface _rocketStorageAddress,
                    LidoInterface _lidoProxyAddress,
                    uint256 _fee,
                    address payable _feesRecipient
                ) {
                    _transferOwnership(_owner);
                    lidoReferralAddress = _lidoReferralAddress;
                    rocketStorage = _rocketStorageAddress;
                    lidoProxyAddress = _lidoProxyAddress;
                    fee = _fee;
                    feesRecipient = _feesRecipient;
                }
                error TransferFailed(address recipient, uint256 amount);
                error NoTokensMinted(address recipient);
                error FeeTooHigh(uint256 fee);
                error ContractNotFound();
                error InvalidFeesRecipient(address attemptedRecipient);
                error IncompatibleFeeRate(uint256 contractRate, uint256 permittedRate);
                event FeeUpdated(uint256 _newFee);
                event FeesRecipientUpdated(address recipient);
                /// @notice Deposits ETH to Lido and forwards minted stETH to caller
                function depositToLido(uint256 maxFeeRate) external payable nonReentrant whenNotPaused {
                    // Check that user has allowed the fee rate
                    if (maxFeeRate < fee) revert IncompatibleFeeRate(fee, maxFeeRate);
                    // Forward deposit minus fee to Lido & get amount of stETH
                    uint256 sharesMinted = lidoProxyAddress.submit{value: msg.value - ((msg.value * fee) / FEE_BASE)}(
                        lidoReferralAddress
                    );
                    if (sharesMinted == 0) revert NoTokensMinted(msg.sender);
                    // Forward minted stETH back to user
                    if (lidoProxyAddress.transferShares(msg.sender, sharesMinted) == 0)
                        revert TransferFailed(msg.sender, sharesMinted);
                    // Withdraw fee
                    if (address(this).balance != 0) feesRecipient.sendValue(address(this).balance);        
                }
                /// @notice Deposits ETH to RocketPool and forwards minted rETH to caller
                function depositToRP(uint256 maxFeeRate) external payable nonReentrant whenNotPaused {
                    // Check that user has allowed the fee rate
                    if (maxFeeRate < fee) revert IncompatibleFeeRate(fee, maxFeeRate);
                    // Load contracts
                    address rocketDepositPoolAddress = getContractAddress(
                        "rocketDepositPool"
                    );
                    RocketDepositPoolInterface rocketDepositPool = RocketDepositPoolInterface(
                            rocketDepositPoolAddress
                        );
                    address rocketTokenRETHAddress = getContractAddress("rocketTokenRETH");
                    RocketTokenRETHInterface rocketTokenRETH = RocketTokenRETHInterface(
                        rocketTokenRETHAddress
                    );
                    // Forward deposit minus fee to RP & get amount of rETH minted
                    uint256 rethBalance1 = rocketTokenRETH.balanceOf(address(this));
                    rocketDepositPool.deposit{value: msg.value - ((msg.value * fee) / FEE_BASE)}();
                    uint256 rethBalance2 = rocketTokenRETH.balanceOf(address(this));
                    if (rethBalance2 <= rethBalance1) revert NoTokensMinted(msg.sender);
                    uint256 rethMinted = rethBalance2 - rethBalance1;
                    // Forward minted rETH back to user
                    if (!rocketTokenRETH.transfer(msg.sender, rethMinted))
                        revert TransferFailed(msg.sender, rethMinted);
                    // Withdraw fee
                    if (address(this).balance != 0) feesRecipient.sendValue(address(this).balance);        
                }
                /// @notice Updates the fee for staking transactions
                /// @dev Fee is in 0.1bp increments. i.e. fee = 10 is setting to 1bp
                /// @param _newFee The new fee for future transactions
                function updateFee(uint256 _newFee) external onlyOwner {
                    if (_newFee > MAX_FEE) revert FeeTooHigh(_newFee);
                    fee = _newFee;
                    emit FeeUpdated(_newFee);
                }
                /// @notice Updates the recipient of the fees collected by the contract
                /// @param _newFeesRecipent The recipient of future fees
                function updateFeesRecipient(address payable _newFeesRecipent)
                    external
                    onlyOwner
                {
                    if (_newFeesRecipent == address(0))
                        revert InvalidFeesRecipient(_newFeesRecipent);
                    feesRecipient = _newFeesRecipent;
                    emit FeesRecipientUpdated(_newFeesRecipent);
                }
                /// @notice Returns several RocketPool constants that the FE needs
                /// @dev Deposit fee in wei. Number needs to be divided by 1e18 to get in percentage
                function fetchRPConstants() external view returns (uint256[4] memory) {
                    address rocketTokenRETHAddress = getContractAddress("rocketTokenRETH");
                    address rocketDAOSettingsAddress = getContractAddress(
                        "rocketDAOProtocolSettingsDeposit"
                    );
                    address rocketVaultAddress = getContractAddress("rocketVault");
                    RocketDAOProtocolSettingsDepositInterface rocketDAOProtocolSettingsDeposit = RocketDAOProtocolSettingsDepositInterface(
                            rocketDAOSettingsAddress
                        );
                    RocketVaultInterface rocketVault = RocketVaultInterface(
                        rocketVaultAddress
                    );
                    RocketTokenRETHInterface rocketTokenRETH = RocketTokenRETHInterface(
                        rocketTokenRETHAddress
                    );
                    uint256 currentDeposits = rocketVault.balanceOf("rocketDepositPool");
                    uint256 depositFee = rocketDAOProtocolSettingsDeposit.getDepositFee();
                    uint256 depositPoolCap = rocketDAOProtocolSettingsDeposit
                        .getMaximumDepositPoolSize();
                    uint256 exchangeRate = rocketTokenRETH.getExchangeRate();
                    return [currentDeposits, depositFee, depositPoolCap, exchangeRate];
                }
                function pause() external onlyOwner {
                    _pause();
                }
                function unpause() external onlyOwner {
                    _unpause();
                }
                /// @dev Get the address of a RocketPool network contract by name
                function getContractAddress(string memory _contractName)
                    internal
                    view
                    returns (address)
                {
                    address contractAddress = rocketStorage.getAddress(
                        keccak256(abi.encodePacked("contract.address", _contractName))
                    );
                    if (contractAddress == address(0)) revert ContractNotFound();
                    return contractAddress;
                }
                /// @notice Recovers arbitrary ERC-20 tokens in case any mistakenly get sent to contract
                /// @param tokenAddress address of the token to be sent
                /// @param tokenAmount amount of token to be sent
                /// @param recipient recipient of tokens 
                function recoverERC20(address tokenAddress, uint256 tokenAmount, address recipient) public virtual onlyOwner {
                    IERC20(tokenAddress).transfer(recipient, tokenAmount);
                }
            }
            pragma solidity >0.4.24 <0.9.0;
            // SPDX-License-Identifier: GPL-3.0
            import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
            /**
             * @title Liquid staking pool
             *
             * For the high-level description of the pool operation please refer to the paper.
             * Pool manages withdrawal keys and fees. It receives ether submitted by users on the ETH 1 side
             * and stakes it via the deposit_contract.sol contract. It doesn't hold ether on it's balance,
             * only a small portion (buffer) of it.
             * It also mints new tokens for rewards generated at the ETH 2.0 side.
             *
             * At the moment withdrawals are not possible in the beacon chain and there's no workaround.
             * Pool will be upgraded to an actual implementation when withdrawals are enabled
             * (Phase 1.5 or 2 of Eth2 launch, likely late 2022 or 2023).
             */
            interface LidoInterface is IERC20 {
                function totalSupply() external view returns (uint256);
                function getTotalShares() external view returns (uint256);
                /**
                 * @notice Stop pool routine operations
                 */
                function stop() external;
                /**
                 * @notice Resume pool routine operations
                 */
                function resume() external;
                /**
                 * @notice Stops accepting new Ether to the protocol
                 *
                 * @dev While accepting new Ether is stopped, calls to the `submit` function,
                 * as well as to the default payable function, will revert.
                 *
                 * Emits `StakingPaused` event.
                 */
                function pauseStaking() external;
                /**
                 * @notice Resumes accepting new Ether to the protocol (if `pauseStaking` was called previously)
                 * NB: Staking could be rate-limited by imposing a limit on the stake amount
                 * at each moment in time, see `setStakingLimit()` and `removeStakingLimit()`
                 *
                 * @dev Preserves staking limit if it was set previously
                 *
                 * Emits `StakingResumed` event
                 */
                function resumeStaking() external;
                /**
                 * @notice Sets the staking rate limit
                 *
                 * @dev Reverts if:
                 * - `_maxStakeLimit` == 0
                 * - `_maxStakeLimit` >= 2^96
                 * - `_maxStakeLimit` < `_stakeLimitIncreasePerBlock`
                 * - `_maxStakeLimit` / `_stakeLimitIncreasePerBlock` >= 2^32 (only if `_stakeLimitIncreasePerBlock` != 0)
                 *
                 * Emits `StakingLimitSet` event
                 *
                 * @param _maxStakeLimit max stake limit value
                 * @param _stakeLimitIncreasePerBlock stake limit increase per single block
                 */
                function setStakingLimit(
                    uint256 _maxStakeLimit,
                    uint256 _stakeLimitIncreasePerBlock
                ) external;
                /**
                 * @notice Removes the staking rate limit
                 *
                 * Emits `StakingLimitRemoved` event
                 */
                function removeStakingLimit() external;
                /**
                 * @notice Check staking state: whether it's paused or not
                 */
                function isStakingPaused() external view returns (bool);
                /**
                 * @notice Returns how much Ether can be staked in the current block
                 * @dev Special return values:
                 * - 2^256 - 1 if staking is unlimited;
                 * - 0 if staking is paused or if limit is exhausted.
                 */
                function getCurrentStakeLimit() external view returns (uint256);
                /**
                 * @notice Returns full info about current stake limit params and state
                 * @dev Might be used for the advanced integration requests.
                 * @return isStakingPaused staking pause state (equivalent to return of isStakingPaused())
                 * @return isStakingLimitSet whether the stake limit is set
                 * @return currentStakeLimit current stake limit (equivalent to return of getCurrentStakeLimit())
                 * @return maxStakeLimit max stake limit
                 * @return maxStakeLimitGrowthBlocks blocks needed to restore max stake limit from the fully exhausted state
                 * @return prevStakeLimit previously reached stake limit
                 * @return prevStakeBlockNumber previously seen block number
                 */
                function getStakeLimitFullInfo()
                    external
                    view
                    returns (
                        bool isStakingPaused,
                        bool isStakingLimitSet,
                        uint256 currentStakeLimit,
                        uint256 maxStakeLimit,
                        uint256 maxStakeLimitGrowthBlocks,
                        uint256 prevStakeLimit,
                        uint256 prevStakeBlockNumber
                    );
                event Stopped();
                event Resumed();
                event StakingPaused();
                event StakingResumed();
                event StakingLimitSet(
                    uint256 maxStakeLimit,
                    uint256 stakeLimitIncreasePerBlock
                );
                event StakingLimitRemoved();
                /**
                 * @notice Set Lido protocol contracts (oracle, treasury, insurance fund).
                 * @param _oracle oracle contract
                 * @param _treasury treasury contract
                 * @param _insuranceFund insurance fund contract
                 */
                function setProtocolContracts(
                    address _oracle,
                    address _treasury,
                    address _insuranceFund
                ) external;
                event ProtocolContactsSet(
                    address oracle,
                    address treasury,
                    address insuranceFund
                );
                /**
                 * @notice Set fee rate to `_feeBasisPoints` basis points.
                 * The fees are accrued when:
                 * - oracles report staking results (beacon chain balance increase)
                 * - validators gain execution layer rewards (priority fees and MEV)
                 * @param _feeBasisPoints Fee rate, in basis points
                 */
                function setFee(uint16 _feeBasisPoints) external;
                /**
                 * @notice Set fee distribution
                 * @param _treasuryFeeBasisPoints basis points go to the treasury,
                 * @param _insuranceFeeBasisPoints basis points go to the insurance fund,
                 * @param _operatorsFeeBasisPoints basis points go to node operators.
                 * @dev The sum has to be 10 000.
                 */
                function setFeeDistribution(
                    uint16 _treasuryFeeBasisPoints,
                    uint16 _insuranceFeeBasisPoints,
                    uint16 _operatorsFeeBasisPoints
                ) external;
                /**
                 * @notice Returns staking rewards fee rate
                 */
                function getFee() external view returns (uint16 feeBasisPoints);
                /**
                 * @notice Returns fee distribution proportion
                 */
                function getFeeDistribution()
                    external
                    view
                    returns (
                        uint16 treasuryFeeBasisPoints,
                        uint16 insuranceFeeBasisPoints,
                        uint16 operatorsFeeBasisPoints
                    );
                event FeeSet(uint16 feeBasisPoints);
                event FeeDistributionSet(
                    uint16 treasuryFeeBasisPoints,
                    uint16 insuranceFeeBasisPoints,
                    uint16 operatorsFeeBasisPoints
                );
                /**
                 * @notice A payable function supposed to be called only by LidoExecutionLayerRewardsVault contract
                 * @dev We need a dedicated function because funds received by the default payable function
                 * are treated as a user deposit
                 */
                function receiveELRewards() external payable;
                // The amount of ETH withdrawn from LidoExecutionLayerRewardsVault contract to Lido contract
                event ELRewardsReceived(uint256 amount);
                /**
                 * @dev Sets limit on amount of ETH to withdraw from execution layer rewards vault per LidoOracle report
                 * @param _limitPoints limit in basis points to amount of ETH to withdraw per LidoOracle report
                 */
                function setELRewardsWithdrawalLimit(uint16 _limitPoints) external;
                // Percent in basis points of total pooled ether allowed to withdraw from LidoExecutionLayerRewardsVault per LidoOracle report
                event ELRewardsWithdrawalLimitSet(uint256 limitPoints);
                /**
                 * @notice Set credentials to withdraw ETH on ETH 2.0 side after the phase 2 is launched to `_withdrawalCredentials`
                 * @dev Note that setWithdrawalCredentials discards all unused signing keys as the signatures are invalidated.
                 * @param _withdrawalCredentials withdrawal credentials field as defined in the Ethereum PoS consensus specs
                 */
                function setWithdrawalCredentials(bytes32 _withdrawalCredentials) external;
                /**
                 * @notice Returns current credentials to withdraw ETH on ETH 2.0 side after the phase 2 is launched
                 */
                function getWithdrawalCredentials() external view returns (bytes memory);
                event WithdrawalCredentialsSet(bytes32 withdrawalCredentials);
                /**
                 * @dev Sets the address of LidoExecutionLayerRewardsVault contract
                 * @param _executionLayerRewardsVault Execution layer rewards vault contract address
                 */
                function setELRewardsVault(address _executionLayerRewardsVault) external;
                // The `executionLayerRewardsVault` was set as the execution layer rewards vault for Lido
                event ELRewardsVaultSet(address executionLayerRewardsVault);
                /**
                 * @notice Ether on the ETH 2.0 side reported by the oracle
                 * @param _epoch Epoch id
                 * @param _eth2balance Balance in wei on the ETH 2.0 side
                 */
                function handleOracleReport(uint256 _epoch, uint256 _eth2balance) external;
                // User functions
                /**
                 * @notice Adds eth to the pool
                 * @return StETH Amount of StETH generated
                 */
                function submit(address _referral) external payable returns (uint256 StETH);
                // Records a deposit made by a user
                event Submitted(address indexed sender, uint256 amount, address referral);
                // The `amount` of ether was sent to the deposit_contract.deposit function
                event Unbuffered(uint256 amount);
                // Requested withdrawal of `etherAmount` to `pubkeyHash` on the ETH 2.0 side, `tokenAmount` burned by `sender`,
                // `sentFromBuffer` was sent on the current Ethereum side.
                event Withdrawal(
                    address indexed sender,
                    uint256 tokenAmount,
                    uint256 sentFromBuffer,
                    bytes32 indexed pubkeyHash,
                    uint256 etherAmount
                );
                // Info functions
                /**
                 * @notice Gets the amount of Ether controlled by the system
                 */
                function getTotalPooledEther() external view returns (uint256);
                /**
                 * @notice Moves `_sharesAmount` token shares from the caller's account to the `_recipient` account.
                 *
                 * @return amount of transferred tokens.
                 * Emits a `TransferShares` event.
                 * Emits a `Transfer` event.
                 *
                 * Requirements:
                 *
                 * - `_recipient` cannot be the zero address.
                 * - the caller must have at least `_sharesAmount` shares.
                 * - the contract must not be paused.
                 *
                 * @dev The `_sharesAmount` argument is the amount of shares, not tokens.
                 */
                function transferShares(address _recipient, uint256 _sharesAmount)
                    external
                    returns (uint256);
                /**
                 * @return the amount of Ether that corresponds to `_sharesAmount` token shares.
                 */
                function getPooledEthByShares(uint256 _sharesAmount)
                    external
                    view
                    returns (uint256);
                /**
                 * @notice Gets the amount of Ether temporary buffered on this contract balance
                 */
                function getBufferedEther() external view returns (uint256);
                /**
                 * @notice Returns the key values related to Beacon-side
                 * @return depositedValidators - number of deposited validators
                 * @return beaconValidators - number of Lido's validators visible in the Beacon state, reported by oracles
                 * @return beaconBalance - total amount of Beacon-side Ether (sum of all the balances of Lido validators)
                 */
                function getBeaconStat()
                    external
                    view
                    returns (
                        uint256 depositedValidators,
                        uint256 beaconValidators,
                        uint256 beaconBalance
                    );
            }
            pragma solidity >0.5.0 <0.9.0;
            // SPDX-License-Identifier: GPL-3.0-only
            interface RocketDAOProtocolSettingsDepositInterface {
                function getDepositEnabled() external view returns (bool);
                function getAssignDepositsEnabled() external view returns (bool);
                function getMinimumDeposit() external view returns (uint256);
                function getMaximumDepositPoolSize() external view returns (uint256);
                function getMaximumDepositAssignments() external view returns (uint256);
                function getDepositFee() external view returns (uint256);
            }
            pragma solidity >0.5.0 <0.9.0;
            // 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;
            }
            pragma solidity >0.5.0 <0.9.0;
            // 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 (uint256);
                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 (int256);
                function getBytes32(bytes32 _key) external view returns (bytes32);
                // Setters
                function setAddress(bytes32 _key, address _value) external;
                function setUint(bytes32 _key, uint256 _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, int256 _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;
            }
            pragma solidity >0.5.0 <0.9.0;
            // 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;
            }
            pragma solidity >0.5.0 <0.9.0;
            // SPDX-License-Identifier: GPL-3.0-only
            import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
            import "@openzeppelin/contracts/token/ERC20/extensions/ERC20Burnable.sol";
            interface RocketVaultInterface {
                function balanceOf(string memory _networkContractName)
                    external
                    view
                    returns (uint256);
                function depositEther() external payable;
                function withdrawEther(uint256 _amount) external;
                function depositToken(
                    string memory _networkContractName,
                    IERC20 _tokenAddress,
                    uint256 _amount
                ) external;
                function withdrawToken(
                    address _withdrawalAddress,
                    IERC20 _tokenAddress,
                    uint256 _amount
                ) external;
                function balanceOfToken(
                    string memory _networkContractName,
                    IERC20 _tokenAddress
                ) external view returns (uint256);
                function transferToken(
                    string memory _networkContractName,
                    IERC20 _tokenAddress,
                    uint256 _amount
                ) external;
                function burnToken(ERC20Burnable _tokenAddress, uint256 _amount) external;
            }
            

            File 2 of 5: AppProxyUpgradeable
            // File: contracts/common/UnstructuredStorage.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            library UnstructuredStorage {
                function getStorageBool(bytes32 position) internal view returns (bool data) {
                    assembly { data := sload(position) }
                }
            
                function getStorageAddress(bytes32 position) internal view returns (address data) {
                    assembly { data := sload(position) }
                }
            
                function getStorageBytes32(bytes32 position) internal view returns (bytes32 data) {
                    assembly { data := sload(position) }
                }
            
                function getStorageUint256(bytes32 position) internal view returns (uint256 data) {
                    assembly { data := sload(position) }
                }
            
                function setStorageBool(bytes32 position, bool data) internal {
                    assembly { sstore(position, data) }
                }
            
                function setStorageAddress(bytes32 position, address data) internal {
                    assembly { sstore(position, data) }
                }
            
                function setStorageBytes32(bytes32 position, bytes32 data) internal {
                    assembly { sstore(position, data) }
                }
            
                function setStorageUint256(bytes32 position, uint256 data) internal {
                    assembly { sstore(position, data) }
                }
            }
            
            // File: contracts/acl/IACL.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            interface IACL {
                function initialize(address permissionsCreator) external;
            
                // TODO: this should be external
                // See https://github.com/ethereum/solidity/issues/4832
                function hasPermission(address who, address where, bytes32 what, bytes how) public view returns (bool);
            }
            
            // File: contracts/common/IVaultRecoverable.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            interface IVaultRecoverable {
                event RecoverToVault(address indexed vault, address indexed token, uint256 amount);
            
                function transferToVault(address token) external;
            
                function allowRecoverability(address token) external view returns (bool);
                function getRecoveryVault() external view returns (address);
            }
            
            // File: contracts/kernel/IKernel.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            
            interface IKernelEvents {
                event SetApp(bytes32 indexed namespace, bytes32 indexed appId, address app);
            }
            
            
            // This should be an interface, but interfaces can't inherit yet :(
            contract IKernel is IKernelEvents, IVaultRecoverable {
                function acl() public view returns (IACL);
                function hasPermission(address who, address where, bytes32 what, bytes how) public view returns (bool);
            
                function setApp(bytes32 namespace, bytes32 appId, address app) public;
                function getApp(bytes32 namespace, bytes32 appId) public view returns (address);
            }
            
            // File: contracts/apps/AppStorage.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            
            contract AppStorage {
                using UnstructuredStorage for bytes32;
            
                /* Hardcoded constants to save gas
                bytes32 internal constant KERNEL_POSITION = keccak256("aragonOS.appStorage.kernel");
                bytes32 internal constant APP_ID_POSITION = keccak256("aragonOS.appStorage.appId");
                */
                bytes32 internal constant KERNEL_POSITION = 0x4172f0f7d2289153072b0a6ca36959e0cbe2efc3afe50fc81636caa96338137b;
                bytes32 internal constant APP_ID_POSITION = 0xd625496217aa6a3453eecb9c3489dc5a53e6c67b444329ea2b2cbc9ff547639b;
            
                function kernel() public view returns (IKernel) {
                    return IKernel(KERNEL_POSITION.getStorageAddress());
                }
            
                function appId() public view returns (bytes32) {
                    return APP_ID_POSITION.getStorageBytes32();
                }
            
                function setKernel(IKernel _kernel) internal {
                    KERNEL_POSITION.setStorageAddress(address(_kernel));
                }
            
                function setAppId(bytes32 _appId) internal {
                    APP_ID_POSITION.setStorageBytes32(_appId);
                }
            }
            
            // File: contracts/common/IsContract.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            contract IsContract {
                /*
                * NOTE: this should NEVER be used for authentication
                * (see pitfalls: https://github.com/fergarrui/ethereum-security/tree/master/contracts/extcodesize).
                *
                * This is only intended to be used as a sanity check that an address is actually a contract,
                * RATHER THAN an address not being a contract.
                */
                function isContract(address _target) internal view returns (bool) {
                    if (_target == address(0)) {
                        return false;
                    }
            
                    uint256 size;
                    assembly { size := extcodesize(_target) }
                    return size > 0;
                }
            }
            
            // File: contracts/lib/misc/ERCProxy.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            contract ERCProxy {
                uint256 internal constant FORWARDING = 1;
                uint256 internal constant UPGRADEABLE = 2;
            
                function proxyType() public pure returns (uint256 proxyTypeId);
                function implementation() public view returns (address codeAddr);
            }
            
            // File: contracts/common/DelegateProxy.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            contract DelegateProxy is ERCProxy, IsContract {
                uint256 internal constant FWD_GAS_LIMIT = 10000;
            
                /**
                * @dev Performs a delegatecall and returns whatever the delegatecall returned (entire context execution will return!)
                * @param _dst Destination address to perform the delegatecall
                * @param _calldata Calldata for the delegatecall
                */
                function delegatedFwd(address _dst, bytes _calldata) internal {
                    require(isContract(_dst));
                    uint256 fwdGasLimit = FWD_GAS_LIMIT;
            
                    assembly {
                        let result := delegatecall(sub(gas, fwdGasLimit), _dst, add(_calldata, 0x20), mload(_calldata), 0, 0)
                        let size := returndatasize
                        let ptr := mload(0x40)
                        returndatacopy(ptr, 0, size)
            
                        // revert instead of invalid() bc if the underlying call failed with invalid() it already wasted gas.
                        // if the call returned error data, forward it
                        switch result case 0 { revert(ptr, size) }
                        default { return(ptr, size) }
                    }
                }
            }
            
            // File: contracts/common/DepositableStorage.sol
            
            pragma solidity 0.4.24;
            
            
            
            contract DepositableStorage {
                using UnstructuredStorage for bytes32;
            
                // keccak256("aragonOS.depositableStorage.depositable")
                bytes32 internal constant DEPOSITABLE_POSITION = 0x665fd576fbbe6f247aff98f5c94a561e3f71ec2d3c988d56f12d342396c50cea;
            
                function isDepositable() public view returns (bool) {
                    return DEPOSITABLE_POSITION.getStorageBool();
                }
            
                function setDepositable(bool _depositable) internal {
                    DEPOSITABLE_POSITION.setStorageBool(_depositable);
                }
            }
            
            // File: contracts/common/DepositableDelegateProxy.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            contract DepositableDelegateProxy is DepositableStorage, DelegateProxy {
                event ProxyDeposit(address sender, uint256 value);
            
                function () external payable {
                    uint256 forwardGasThreshold = FWD_GAS_LIMIT;
                    bytes32 isDepositablePosition = DEPOSITABLE_POSITION;
            
                    // Optimized assembly implementation to prevent EIP-1884 from breaking deposits, reference code in Solidity:
                    // https://github.com/aragon/aragonOS/blob/v4.2.1/contracts/common/DepositableDelegateProxy.sol#L10-L20
                    assembly {
                        // Continue only if the gas left is lower than the threshold for forwarding to the implementation code,
                        // otherwise continue outside of the assembly block.
                        if lt(gas, forwardGasThreshold) {
                            // Only accept the deposit and emit an event if all of the following are true:
                            // the proxy accepts deposits (isDepositable), msg.data.length == 0, and msg.value > 0
                            if and(and(sload(isDepositablePosition), iszero(calldatasize)), gt(callvalue, 0)) {
                                // Equivalent Solidity code for emitting the event:
                                // emit ProxyDeposit(msg.sender, msg.value);
            
                                let logData := mload(0x40) // free memory pointer
                                mstore(logData, caller) // add 'msg.sender' to the log data (first event param)
                                mstore(add(logData, 0x20), callvalue) // add 'msg.value' to the log data (second event param)
            
                                // Emit an event with one topic to identify the event: keccak256('ProxyDeposit(address,uint256)') = 0x15ee...dee1
                                log1(logData, 0x40, 0x15eeaa57c7bd188c1388020bcadc2c436ec60d647d36ef5b9eb3c742217ddee1)
            
                                stop() // Stop. Exits execution context
                            }
            
                            // If any of above checks failed, revert the execution (if ETH was sent, it is returned to the sender)
                            revert(0, 0)
                        }
                    }
            
                    address target = implementation();
                    delegatedFwd(target, msg.data);
                }
            }
            
            // File: contracts/kernel/KernelConstants.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            contract KernelAppIds {
                /* Hardcoded constants to save gas
                bytes32 internal constant KERNEL_CORE_APP_ID = apmNamehash("kernel");
                bytes32 internal constant KERNEL_DEFAULT_ACL_APP_ID = apmNamehash("acl");
                bytes32 internal constant KERNEL_DEFAULT_VAULT_APP_ID = apmNamehash("vault");
                */
                bytes32 internal constant KERNEL_CORE_APP_ID = 0x3b4bf6bf3ad5000ecf0f989d5befde585c6860fea3e574a4fab4c49d1c177d9c;
                bytes32 internal constant KERNEL_DEFAULT_ACL_APP_ID = 0xe3262375f45a6e2026b7e7b18c2b807434f2508fe1a2a3dfb493c7df8f4aad6a;
                bytes32 internal constant KERNEL_DEFAULT_VAULT_APP_ID = 0x7e852e0fcfce6551c13800f1e7476f982525c2b5277ba14b24339c68416336d1;
            }
            
            
            contract KernelNamespaceConstants {
                /* Hardcoded constants to save gas
                bytes32 internal constant KERNEL_CORE_NAMESPACE = keccak256("core");
                bytes32 internal constant KERNEL_APP_BASES_NAMESPACE = keccak256("base");
                bytes32 internal constant KERNEL_APP_ADDR_NAMESPACE = keccak256("app");
                */
                bytes32 internal constant KERNEL_CORE_NAMESPACE = 0xc681a85306374a5ab27f0bbc385296a54bcd314a1948b6cf61c4ea1bc44bb9f8;
                bytes32 internal constant KERNEL_APP_BASES_NAMESPACE = 0xf1f3eb40f5bc1ad1344716ced8b8a0431d840b5783aea1fd01786bc26f35ac0f;
                bytes32 internal constant KERNEL_APP_ADDR_NAMESPACE = 0xd6f028ca0e8edb4a8c9757ca4fdccab25fa1e0317da1188108f7d2dee14902fb;
            }
            
            // File: contracts/apps/AppProxyBase.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            
            
            contract AppProxyBase is AppStorage, DepositableDelegateProxy, KernelNamespaceConstants {
                /**
                * @dev Initialize AppProxy
                * @param _kernel Reference to organization kernel for the app
                * @param _appId Identifier for app
                * @param _initializePayload Payload for call to be made after setup to initialize
                */
                constructor(IKernel _kernel, bytes32 _appId, bytes _initializePayload) public {
                    setKernel(_kernel);
                    setAppId(_appId);
            
                    // Implicit check that kernel is actually a Kernel
                    // The EVM doesn't actually provide a way for us to make sure, but we can force a revert to
                    // occur if the kernel is set to 0x0 or a non-code address when we try to call a method on
                    // it.
                    address appCode = getAppBase(_appId);
            
                    // If initialize payload is provided, it will be executed
                    if (_initializePayload.length > 0) {
                        require(isContract(appCode));
                        // Cannot make delegatecall as a delegateproxy.delegatedFwd as it
                        // returns ending execution context and halts contract deployment
                        require(appCode.delegatecall(_initializePayload));
                    }
                }
            
                function getAppBase(bytes32 _appId) internal view returns (address) {
                    return kernel().getApp(KERNEL_APP_BASES_NAMESPACE, _appId);
                }
            }
            
            // File: contracts/apps/AppProxyUpgradeable.sol
            
            pragma solidity 0.4.24;
            
            
            
            contract AppProxyUpgradeable is AppProxyBase {
                /**
                * @dev Initialize AppProxyUpgradeable (makes it an upgradeable Aragon app)
                * @param _kernel Reference to organization kernel for the app
                * @param _appId Identifier for app
                * @param _initializePayload Payload for call to be made after setup to initialize
                */
                constructor(IKernel _kernel, bytes32 _appId, bytes _initializePayload)
                    AppProxyBase(_kernel, _appId, _initializePayload)
                    public // solium-disable-line visibility-first
                {
                    // solium-disable-previous-line no-empty-blocks
                }
            
                /**
                 * @dev ERC897, the address the proxy would delegate calls to
                 */
                function implementation() public view returns (address) {
                    return getAppBase(appId());
                }
            
                /**
                 * @dev ERC897, whether it is a forwarding (1) or an upgradeable (2) proxy
                 */
                function proxyType() public pure returns (uint256 proxyTypeId) {
                    return UPGRADEABLE;
                }
            }

            File 3 of 5: KernelProxy
            /**
             *Submitted for verification at Etherscan.io on 2020-02-06
            */
            
            // File: contracts/acl/IACL.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            interface IACL {
                function initialize(address permissionsCreator) external;
            
                // TODO: this should be external
                // See https://github.com/ethereum/solidity/issues/4832
                function hasPermission(address who, address where, bytes32 what, bytes how) public view returns (bool);
            }
            
            // File: contracts/common/IVaultRecoverable.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            interface IVaultRecoverable {
                event RecoverToVault(address indexed vault, address indexed token, uint256 amount);
            
                function transferToVault(address token) external;
            
                function allowRecoverability(address token) external view returns (bool);
                function getRecoveryVault() external view returns (address);
            }
            
            // File: contracts/kernel/IKernel.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            
            interface IKernelEvents {
                event SetApp(bytes32 indexed namespace, bytes32 indexed appId, address app);
            }
            
            
            // This should be an interface, but interfaces can't inherit yet :(
            contract IKernel is IKernelEvents, IVaultRecoverable {
                function acl() public view returns (IACL);
                function hasPermission(address who, address where, bytes32 what, bytes how) public view returns (bool);
            
                function setApp(bytes32 namespace, bytes32 appId, address app) public;
                function getApp(bytes32 namespace, bytes32 appId) public view returns (address);
            }
            
            // File: contracts/kernel/KernelConstants.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            contract KernelAppIds {
                /* Hardcoded constants to save gas
                bytes32 internal constant KERNEL_CORE_APP_ID = apmNamehash("kernel");
                bytes32 internal constant KERNEL_DEFAULT_ACL_APP_ID = apmNamehash("acl");
                bytes32 internal constant KERNEL_DEFAULT_VAULT_APP_ID = apmNamehash("vault");
                */
                bytes32 internal constant KERNEL_CORE_APP_ID = 0x3b4bf6bf3ad5000ecf0f989d5befde585c6860fea3e574a4fab4c49d1c177d9c;
                bytes32 internal constant KERNEL_DEFAULT_ACL_APP_ID = 0xe3262375f45a6e2026b7e7b18c2b807434f2508fe1a2a3dfb493c7df8f4aad6a;
                bytes32 internal constant KERNEL_DEFAULT_VAULT_APP_ID = 0x7e852e0fcfce6551c13800f1e7476f982525c2b5277ba14b24339c68416336d1;
            }
            
            
            contract KernelNamespaceConstants {
                /* Hardcoded constants to save gas
                bytes32 internal constant KERNEL_CORE_NAMESPACE = keccak256("core");
                bytes32 internal constant KERNEL_APP_BASES_NAMESPACE = keccak256("base");
                bytes32 internal constant KERNEL_APP_ADDR_NAMESPACE = keccak256("app");
                */
                bytes32 internal constant KERNEL_CORE_NAMESPACE = 0xc681a85306374a5ab27f0bbc385296a54bcd314a1948b6cf61c4ea1bc44bb9f8;
                bytes32 internal constant KERNEL_APP_BASES_NAMESPACE = 0xf1f3eb40f5bc1ad1344716ced8b8a0431d840b5783aea1fd01786bc26f35ac0f;
                bytes32 internal constant KERNEL_APP_ADDR_NAMESPACE = 0xd6f028ca0e8edb4a8c9757ca4fdccab25fa1e0317da1188108f7d2dee14902fb;
            }
            
            // File: contracts/kernel/KernelStorage.sol
            
            pragma solidity 0.4.24;
            
            
            contract KernelStorage {
                // namespace => app id => address
                mapping (bytes32 => mapping (bytes32 => address)) public apps;
                bytes32 public recoveryVaultAppId;
            }
            
            // File: contracts/acl/ACLSyntaxSugar.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            contract ACLSyntaxSugar {
                function arr() internal pure returns (uint256[]) {
                    return new uint256[](0);
                }
            
                function arr(bytes32 _a) internal pure returns (uint256[] r) {
                    return arr(uint256(_a));
                }
            
                function arr(bytes32 _a, bytes32 _b) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b));
                }
            
                function arr(address _a) internal pure returns (uint256[] r) {
                    return arr(uint256(_a));
                }
            
                function arr(address _a, address _b) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b));
                }
            
                function arr(address _a, uint256 _b, uint256 _c) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), _b, _c);
                }
            
                function arr(address _a, uint256 _b, uint256 _c, uint256 _d) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), _b, _c, _d);
                }
            
                function arr(address _a, uint256 _b) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b));
                }
            
                function arr(address _a, address _b, uint256 _c, uint256 _d, uint256 _e) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b), _c, _d, _e);
                }
            
                function arr(address _a, address _b, address _c) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b), uint256(_c));
                }
            
                function arr(address _a, address _b, uint256 _c) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b), uint256(_c));
                }
            
                function arr(uint256 _a) internal pure returns (uint256[] r) {
                    r = new uint256[](1);
                    r[0] = _a;
                }
            
                function arr(uint256 _a, uint256 _b) internal pure returns (uint256[] r) {
                    r = new uint256[](2);
                    r[0] = _a;
                    r[1] = _b;
                }
            
                function arr(uint256 _a, uint256 _b, uint256 _c) internal pure returns (uint256[] r) {
                    r = new uint256[](3);
                    r[0] = _a;
                    r[1] = _b;
                    r[2] = _c;
                }
            
                function arr(uint256 _a, uint256 _b, uint256 _c, uint256 _d) internal pure returns (uint256[] r) {
                    r = new uint256[](4);
                    r[0] = _a;
                    r[1] = _b;
                    r[2] = _c;
                    r[3] = _d;
                }
            
                function arr(uint256 _a, uint256 _b, uint256 _c, uint256 _d, uint256 _e) internal pure returns (uint256[] r) {
                    r = new uint256[](5);
                    r[0] = _a;
                    r[1] = _b;
                    r[2] = _c;
                    r[3] = _d;
                    r[4] = _e;
                }
            }
            
            
            contract ACLHelpers {
                function decodeParamOp(uint256 _x) internal pure returns (uint8 b) {
                    return uint8(_x >> (8 * 30));
                }
            
                function decodeParamId(uint256 _x) internal pure returns (uint8 b) {
                    return uint8(_x >> (8 * 31));
                }
            
                function decodeParamsList(uint256 _x) internal pure returns (uint32 a, uint32 b, uint32 c) {
                    a = uint32(_x);
                    b = uint32(_x >> (8 * 4));
                    c = uint32(_x >> (8 * 8));
                }
            }
            
            // File: contracts/common/ConversionHelpers.sol
            
            pragma solidity ^0.4.24;
            
            
            library ConversionHelpers {
                string private constant ERROR_IMPROPER_LENGTH = "CONVERSION_IMPROPER_LENGTH";
            
                function dangerouslyCastUintArrayToBytes(uint256[] memory _input) internal pure returns (bytes memory output) {
                    // Force cast the uint256[] into a bytes array, by overwriting its length
                    // Note that the bytes array doesn't need to be initialized as we immediately overwrite it
                    // with the input and a new length. The input becomes invalid from this point forward.
                    uint256 byteLength = _input.length * 32;
                    assembly {
                        output := _input
                        mstore(output, byteLength)
                    }
                }
            
                function dangerouslyCastBytesToUintArray(bytes memory _input) internal pure returns (uint256[] memory output) {
                    // Force cast the bytes array into a uint256[], by overwriting its length
                    // Note that the uint256[] doesn't need to be initialized as we immediately overwrite it
                    // with the input and a new length. The input becomes invalid from this point forward.
                    uint256 intsLength = _input.length / 32;
                    require(_input.length == intsLength * 32, ERROR_IMPROPER_LENGTH);
            
                    assembly {
                        output := _input
                        mstore(output, intsLength)
                    }
                }
            }
            
            // File: contracts/common/IsContract.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            contract IsContract {
                /*
                * NOTE: this should NEVER be used for authentication
                * (see pitfalls: https://github.com/fergarrui/ethereum-security/tree/master/contracts/extcodesize).
                *
                * This is only intended to be used as a sanity check that an address is actually a contract,
                * RATHER THAN an address not being a contract.
                */
                function isContract(address _target) internal view returns (bool) {
                    if (_target == address(0)) {
                        return false;
                    }
            
                    uint256 size;
                    assembly { size := extcodesize(_target) }
                    return size > 0;
                }
            }
            
            // File: contracts/common/Uint256Helpers.sol
            
            pragma solidity ^0.4.24;
            
            
            library Uint256Helpers {
                uint256 private constant MAX_UINT64 = uint64(-1);
            
                string private constant ERROR_NUMBER_TOO_BIG = "UINT64_NUMBER_TOO_BIG";
            
                function toUint64(uint256 a) internal pure returns (uint64) {
                    require(a <= MAX_UINT64, ERROR_NUMBER_TOO_BIG);
                    return uint64(a);
                }
            }
            
            // File: contracts/common/TimeHelpers.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            contract TimeHelpers {
                using Uint256Helpers for uint256;
            
                /**
                * @dev Returns the current block number.
                *      Using a function rather than `block.number` allows us to easily mock the block number in
                *      tests.
                */
                function getBlockNumber() internal view returns (uint256) {
                    return block.number;
                }
            
                /**
                * @dev Returns the current block number, converted to uint64.
                *      Using a function rather than `block.number` allows us to easily mock the block number in
                *      tests.
                */
                function getBlockNumber64() internal view returns (uint64) {
                    return getBlockNumber().toUint64();
                }
            
                /**
                * @dev Returns the current timestamp.
                *      Using a function rather than `block.timestamp` allows us to easily mock it in
                *      tests.
                */
                function getTimestamp() internal view returns (uint256) {
                    return block.timestamp; // solium-disable-line security/no-block-members
                }
            
                /**
                * @dev Returns the current timestamp, converted to uint64.
                *      Using a function rather than `block.timestamp` allows us to easily mock it in
                *      tests.
                */
                function getTimestamp64() internal view returns (uint64) {
                    return getTimestamp().toUint64();
                }
            }
            
            // File: contracts/common/UnstructuredStorage.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            library UnstructuredStorage {
                function getStorageBool(bytes32 position) internal view returns (bool data) {
                    assembly { data := sload(position) }
                }
            
                function getStorageAddress(bytes32 position) internal view returns (address data) {
                    assembly { data := sload(position) }
                }
            
                function getStorageBytes32(bytes32 position) internal view returns (bytes32 data) {
                    assembly { data := sload(position) }
                }
            
                function getStorageUint256(bytes32 position) internal view returns (uint256 data) {
                    assembly { data := sload(position) }
                }
            
                function setStorageBool(bytes32 position, bool data) internal {
                    assembly { sstore(position, data) }
                }
            
                function setStorageAddress(bytes32 position, address data) internal {
                    assembly { sstore(position, data) }
                }
            
                function setStorageBytes32(bytes32 position, bytes32 data) internal {
                    assembly { sstore(position, data) }
                }
            
                function setStorageUint256(bytes32 position, uint256 data) internal {
                    assembly { sstore(position, data) }
                }
            }
            
            // File: contracts/common/Initializable.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            
            contract Initializable is TimeHelpers {
                using UnstructuredStorage for bytes32;
            
                // keccak256("aragonOS.initializable.initializationBlock")
                bytes32 internal constant INITIALIZATION_BLOCK_POSITION = 0xebb05b386a8d34882b8711d156f463690983dc47815980fb82aeeff1aa43579e;
            
                string private constant ERROR_ALREADY_INITIALIZED = "INIT_ALREADY_INITIALIZED";
                string private constant ERROR_NOT_INITIALIZED = "INIT_NOT_INITIALIZED";
            
                modifier onlyInit {
                    require(getInitializationBlock() == 0, ERROR_ALREADY_INITIALIZED);
                    _;
                }
            
                modifier isInitialized {
                    require(hasInitialized(), ERROR_NOT_INITIALIZED);
                    _;
                }
            
                /**
                * @return Block number in which the contract was initialized
                */
                function getInitializationBlock() public view returns (uint256) {
                    return INITIALIZATION_BLOCK_POSITION.getStorageUint256();
                }
            
                /**
                * @return Whether the contract has been initialized by the time of the current block
                */
                function hasInitialized() public view returns (bool) {
                    uint256 initializationBlock = getInitializationBlock();
                    return initializationBlock != 0 && getBlockNumber() >= initializationBlock;
                }
            
                /**
                * @dev Function to be called by top level contract after initialization has finished.
                */
                function initialized() internal onlyInit {
                    INITIALIZATION_BLOCK_POSITION.setStorageUint256(getBlockNumber());
                }
            
                /**
                * @dev Function to be called by top level contract after initialization to enable the contract
                *      at a future block number rather than immediately.
                */
                function initializedAt(uint256 _blockNumber) internal onlyInit {
                    INITIALIZATION_BLOCK_POSITION.setStorageUint256(_blockNumber);
                }
            }
            
            // File: contracts/common/Petrifiable.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            contract Petrifiable is Initializable {
                // Use block UINT256_MAX (which should be never) as the initializable date
                uint256 internal constant PETRIFIED_BLOCK = uint256(-1);
            
                function isPetrified() public view returns (bool) {
                    return getInitializationBlock() == PETRIFIED_BLOCK;
                }
            
                /**
                * @dev Function to be called by top level contract to prevent being initialized.
                *      Useful for freezing base contracts when they're used behind proxies.
                */
                function petrify() internal onlyInit {
                    initializedAt(PETRIFIED_BLOCK);
                }
            }
            
            // File: contracts/lib/token/ERC20.sol
            
            // See https://github.com/OpenZeppelin/openzeppelin-solidity/blob/a9f910d34f0ab33a1ae5e714f69f9596a02b4d91/contracts/token/ERC20/ERC20.sol
            
            pragma solidity ^0.4.24;
            
            
            /**
             * @title ERC20 interface
             * @dev see https://github.com/ethereum/EIPs/issues/20
             */
            contract ERC20 {
                function totalSupply() public view returns (uint256);
            
                function balanceOf(address _who) public view returns (uint256);
            
                function allowance(address _owner, address _spender)
                    public view returns (uint256);
            
                function transfer(address _to, uint256 _value) public returns (bool);
            
                function approve(address _spender, uint256 _value)
                    public returns (bool);
            
                function transferFrom(address _from, address _to, uint256 _value)
                    public returns (bool);
            
                event Transfer(
                    address indexed from,
                    address indexed to,
                    uint256 value
                );
            
                event Approval(
                    address indexed owner,
                    address indexed spender,
                    uint256 value
                );
            }
            
            // File: contracts/common/EtherTokenConstant.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            // aragonOS and aragon-apps rely on address(0) to denote native ETH, in
            // contracts where both tokens and ETH are accepted
            contract EtherTokenConstant {
                address internal constant ETH = address(0);
            }
            
            // File: contracts/common/SafeERC20.sol
            
            // Inspired by AdEx (https://github.com/AdExNetwork/adex-protocol-eth/blob/b9df617829661a7518ee10f4cb6c4108659dd6d5/contracts/libs/SafeERC20.sol)
            // and 0x (https://github.com/0xProject/0x-monorepo/blob/737d1dc54d72872e24abce5a1dbe1b66d35fa21a/contracts/protocol/contracts/protocol/AssetProxy/ERC20Proxy.sol#L143)
            
            pragma solidity ^0.4.24;
            
            
            
            library SafeERC20 {
                // Before 0.5, solidity has a mismatch between `address.transfer()` and `token.transfer()`:
                // https://github.com/ethereum/solidity/issues/3544
                bytes4 private constant TRANSFER_SELECTOR = 0xa9059cbb;
            
                string private constant ERROR_TOKEN_BALANCE_REVERTED = "SAFE_ERC_20_BALANCE_REVERTED";
                string private constant ERROR_TOKEN_ALLOWANCE_REVERTED = "SAFE_ERC_20_ALLOWANCE_REVERTED";
            
                function invokeAndCheckSuccess(address _addr, bytes memory _calldata)
                    private
                    returns (bool)
                {
                    bool ret;
                    assembly {
                        let ptr := mload(0x40)    // free memory pointer
            
                        let success := call(
                            gas,                  // forward all gas
                            _addr,                // address
                            0,                    // no value
                            add(_calldata, 0x20), // calldata start
                            mload(_calldata),     // calldata length
                            ptr,                  // write output over free memory
                            0x20                  // uint256 return
                        )
            
                        if gt(success, 0) {
                            // Check number of bytes returned from last function call
                            switch returndatasize
            
                            // No bytes returned: assume success
                            case 0 {
                                ret := 1
                            }
            
                            // 32 bytes returned: check if non-zero
                            case 0x20 {
                                // Only return success if returned data was true
                                // Already have output in ptr
                                ret := eq(mload(ptr), 1)
                            }
            
                            // Not sure what was returned: don't mark as success
                            default { }
                        }
                    }
                    return ret;
                }
            
                function staticInvoke(address _addr, bytes memory _calldata)
                    private
                    view
                    returns (bool, uint256)
                {
                    bool success;
                    uint256 ret;
                    assembly {
                        let ptr := mload(0x40)    // free memory pointer
            
                        success := staticcall(
                            gas,                  // forward all gas
                            _addr,                // address
                            add(_calldata, 0x20), // calldata start
                            mload(_calldata),     // calldata length
                            ptr,                  // write output over free memory
                            0x20                  // uint256 return
                        )
            
                        if gt(success, 0) {
                            ret := mload(ptr)
                        }
                    }
                    return (success, ret);
                }
            
                /**
                * @dev Same as a standards-compliant ERC20.transfer() that never reverts (returns false).
                *      Note that this makes an external call to the token.
                */
                function safeTransfer(ERC20 _token, address _to, uint256 _amount) internal returns (bool) {
                    bytes memory transferCallData = abi.encodeWithSelector(
                        TRANSFER_SELECTOR,
                        _to,
                        _amount
                    );
                    return invokeAndCheckSuccess(_token, transferCallData);
                }
            
                /**
                * @dev Same as a standards-compliant ERC20.transferFrom() that never reverts (returns false).
                *      Note that this makes an external call to the token.
                */
                function safeTransferFrom(ERC20 _token, address _from, address _to, uint256 _amount) internal returns (bool) {
                    bytes memory transferFromCallData = abi.encodeWithSelector(
                        _token.transferFrom.selector,
                        _from,
                        _to,
                        _amount
                    );
                    return invokeAndCheckSuccess(_token, transferFromCallData);
                }
            
                /**
                * @dev Same as a standards-compliant ERC20.approve() that never reverts (returns false).
                *      Note that this makes an external call to the token.
                */
                function safeApprove(ERC20 _token, address _spender, uint256 _amount) internal returns (bool) {
                    bytes memory approveCallData = abi.encodeWithSelector(
                        _token.approve.selector,
                        _spender,
                        _amount
                    );
                    return invokeAndCheckSuccess(_token, approveCallData);
                }
            
                /**
                * @dev Static call into ERC20.balanceOf().
                * Reverts if the call fails for some reason (should never fail).
                */
                function staticBalanceOf(ERC20 _token, address _owner) internal view returns (uint256) {
                    bytes memory balanceOfCallData = abi.encodeWithSelector(
                        _token.balanceOf.selector,
                        _owner
                    );
            
                    (bool success, uint256 tokenBalance) = staticInvoke(_token, balanceOfCallData);
                    require(success, ERROR_TOKEN_BALANCE_REVERTED);
            
                    return tokenBalance;
                }
            
                /**
                * @dev Static call into ERC20.allowance().
                * Reverts if the call fails for some reason (should never fail).
                */
                function staticAllowance(ERC20 _token, address _owner, address _spender) internal view returns (uint256) {
                    bytes memory allowanceCallData = abi.encodeWithSelector(
                        _token.allowance.selector,
                        _owner,
                        _spender
                    );
            
                    (bool success, uint256 allowance) = staticInvoke(_token, allowanceCallData);
                    require(success, ERROR_TOKEN_ALLOWANCE_REVERTED);
            
                    return allowance;
                }
            
                /**
                * @dev Static call into ERC20.totalSupply().
                * Reverts if the call fails for some reason (should never fail).
                */
                function staticTotalSupply(ERC20 _token) internal view returns (uint256) {
                    bytes memory totalSupplyCallData = abi.encodeWithSelector(_token.totalSupply.selector);
            
                    (bool success, uint256 totalSupply) = staticInvoke(_token, totalSupplyCallData);
                    require(success, ERROR_TOKEN_ALLOWANCE_REVERTED);
            
                    return totalSupply;
                }
            }
            
            // File: contracts/common/VaultRecoverable.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            
            
            
            
            contract VaultRecoverable is IVaultRecoverable, EtherTokenConstant, IsContract {
                using SafeERC20 for ERC20;
            
                string private constant ERROR_DISALLOWED = "RECOVER_DISALLOWED";
                string private constant ERROR_VAULT_NOT_CONTRACT = "RECOVER_VAULT_NOT_CONTRACT";
                string private constant ERROR_TOKEN_TRANSFER_FAILED = "RECOVER_TOKEN_TRANSFER_FAILED";
            
                /**
                 * @notice Send funds to recovery Vault. This contract should never receive funds,
                 *         but in case it does, this function allows one to recover them.
                 * @param _token Token balance to be sent to recovery vault.
                 */
                function transferToVault(address _token) external {
                    require(allowRecoverability(_token), ERROR_DISALLOWED);
                    address vault = getRecoveryVault();
                    require(isContract(vault), ERROR_VAULT_NOT_CONTRACT);
            
                    uint256 balance;
                    if (_token == ETH) {
                        balance = address(this).balance;
                        vault.transfer(balance);
                    } else {
                        ERC20 token = ERC20(_token);
                        balance = token.staticBalanceOf(this);
                        require(token.safeTransfer(vault, balance), ERROR_TOKEN_TRANSFER_FAILED);
                    }
            
                    emit RecoverToVault(vault, _token, balance);
                }
            
                /**
                * @dev By default deriving from AragonApp makes it recoverable
                * @param token Token address that would be recovered
                * @return bool whether the app allows the recovery
                */
                function allowRecoverability(address token) public view returns (bool) {
                    return true;
                }
            
                // Cast non-implemented interface to be public so we can use it internally
                function getRecoveryVault() public view returns (address);
            }
            
            // File: contracts/apps/AppStorage.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            
            contract AppStorage {
                using UnstructuredStorage for bytes32;
            
                /* Hardcoded constants to save gas
                bytes32 internal constant KERNEL_POSITION = keccak256("aragonOS.appStorage.kernel");
                bytes32 internal constant APP_ID_POSITION = keccak256("aragonOS.appStorage.appId");
                */
                bytes32 internal constant KERNEL_POSITION = 0x4172f0f7d2289153072b0a6ca36959e0cbe2efc3afe50fc81636caa96338137b;
                bytes32 internal constant APP_ID_POSITION = 0xd625496217aa6a3453eecb9c3489dc5a53e6c67b444329ea2b2cbc9ff547639b;
            
                function kernel() public view returns (IKernel) {
                    return IKernel(KERNEL_POSITION.getStorageAddress());
                }
            
                function appId() public view returns (bytes32) {
                    return APP_ID_POSITION.getStorageBytes32();
                }
            
                function setKernel(IKernel _kernel) internal {
                    KERNEL_POSITION.setStorageAddress(address(_kernel));
                }
            
                function setAppId(bytes32 _appId) internal {
                    APP_ID_POSITION.setStorageBytes32(_appId);
                }
            }
            
            // File: contracts/lib/misc/ERCProxy.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            contract ERCProxy {
                uint256 internal constant FORWARDING = 1;
                uint256 internal constant UPGRADEABLE = 2;
            
                function proxyType() public pure returns (uint256 proxyTypeId);
                function implementation() public view returns (address codeAddr);
            }
            
            // File: contracts/common/DelegateProxy.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            contract DelegateProxy is ERCProxy, IsContract {
                uint256 internal constant FWD_GAS_LIMIT = 10000;
            
                /**
                * @dev Performs a delegatecall and returns whatever the delegatecall returned (entire context execution will return!)
                * @param _dst Destination address to perform the delegatecall
                * @param _calldata Calldata for the delegatecall
                */
                function delegatedFwd(address _dst, bytes _calldata) internal {
                    require(isContract(_dst));
                    uint256 fwdGasLimit = FWD_GAS_LIMIT;
            
                    assembly {
                        let result := delegatecall(sub(gas, fwdGasLimit), _dst, add(_calldata, 0x20), mload(_calldata), 0, 0)
                        let size := returndatasize
                        let ptr := mload(0x40)
                        returndatacopy(ptr, 0, size)
            
                        // revert instead of invalid() bc if the underlying call failed with invalid() it already wasted gas.
                        // if the call returned error data, forward it
                        switch result case 0 { revert(ptr, size) }
                        default { return(ptr, size) }
                    }
                }
            }
            
            // File: contracts/common/DepositableStorage.sol
            
            pragma solidity 0.4.24;
            
            
            
            contract DepositableStorage {
                using UnstructuredStorage for bytes32;
            
                // keccak256("aragonOS.depositableStorage.depositable")
                bytes32 internal constant DEPOSITABLE_POSITION = 0x665fd576fbbe6f247aff98f5c94a561e3f71ec2d3c988d56f12d342396c50cea;
            
                function isDepositable() public view returns (bool) {
                    return DEPOSITABLE_POSITION.getStorageBool();
                }
            
                function setDepositable(bool _depositable) internal {
                    DEPOSITABLE_POSITION.setStorageBool(_depositable);
                }
            }
            
            // File: contracts/common/DepositableDelegateProxy.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            contract DepositableDelegateProxy is DepositableStorage, DelegateProxy {
                event ProxyDeposit(address sender, uint256 value);
            
                function () external payable {
                    uint256 forwardGasThreshold = FWD_GAS_LIMIT;
                    bytes32 isDepositablePosition = DEPOSITABLE_POSITION;
            
                    // Optimized assembly implementation to prevent EIP-1884 from breaking deposits, reference code in Solidity:
                    // https://github.com/aragon/aragonOS/blob/v4.2.1/contracts/common/DepositableDelegateProxy.sol#L10-L20
                    assembly {
                        // Continue only if the gas left is lower than the threshold for forwarding to the implementation code,
                        // otherwise continue outside of the assembly block.
                        if lt(gas, forwardGasThreshold) {
                            // Only accept the deposit and emit an event if all of the following are true:
                            // the proxy accepts deposits (isDepositable), msg.data.length == 0, and msg.value > 0
                            if and(and(sload(isDepositablePosition), iszero(calldatasize)), gt(callvalue, 0)) {
                                // Equivalent Solidity code for emitting the event:
                                // emit ProxyDeposit(msg.sender, msg.value);
            
                                let logData := mload(0x40) // free memory pointer
                                mstore(logData, caller) // add 'msg.sender' to the log data (first event param)
                                mstore(add(logData, 0x20), callvalue) // add 'msg.value' to the log data (second event param)
            
                                // Emit an event with one topic to identify the event: keccak256('ProxyDeposit(address,uint256)') = 0x15ee...dee1
                                log1(logData, 0x40, 0x15eeaa57c7bd188c1388020bcadc2c436ec60d647d36ef5b9eb3c742217ddee1)
            
                                stop() // Stop. Exits execution context
                            }
            
                            // If any of above checks failed, revert the execution (if ETH was sent, it is returned to the sender)
                            revert(0, 0)
                        }
                    }
            
                    address target = implementation();
                    delegatedFwd(target, msg.data);
                }
            }
            
            // File: contracts/apps/AppProxyBase.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            
            
            contract AppProxyBase is AppStorage, DepositableDelegateProxy, KernelNamespaceConstants {
                /**
                * @dev Initialize AppProxy
                * @param _kernel Reference to organization kernel for the app
                * @param _appId Identifier for app
                * @param _initializePayload Payload for call to be made after setup to initialize
                */
                constructor(IKernel _kernel, bytes32 _appId, bytes _initializePayload) public {
                    setKernel(_kernel);
                    setAppId(_appId);
            
                    // Implicit check that kernel is actually a Kernel
                    // The EVM doesn't actually provide a way for us to make sure, but we can force a revert to
                    // occur if the kernel is set to 0x0 or a non-code address when we try to call a method on
                    // it.
                    address appCode = getAppBase(_appId);
            
                    // If initialize payload is provided, it will be executed
                    if (_initializePayload.length > 0) {
                        require(isContract(appCode));
                        // Cannot make delegatecall as a delegateproxy.delegatedFwd as it
                        // returns ending execution context and halts contract deployment
                        require(appCode.delegatecall(_initializePayload));
                    }
                }
            
                function getAppBase(bytes32 _appId) internal view returns (address) {
                    return kernel().getApp(KERNEL_APP_BASES_NAMESPACE, _appId);
                }
            }
            
            // File: contracts/apps/AppProxyUpgradeable.sol
            
            pragma solidity 0.4.24;
            
            
            
            contract AppProxyUpgradeable is AppProxyBase {
                /**
                * @dev Initialize AppProxyUpgradeable (makes it an upgradeable Aragon app)
                * @param _kernel Reference to organization kernel for the app
                * @param _appId Identifier for app
                * @param _initializePayload Payload for call to be made after setup to initialize
                */
                constructor(IKernel _kernel, bytes32 _appId, bytes _initializePayload)
                    AppProxyBase(_kernel, _appId, _initializePayload)
                    public // solium-disable-line visibility-first
                {
                    // solium-disable-previous-line no-empty-blocks
                }
            
                /**
                 * @dev ERC897, the address the proxy would delegate calls to
                 */
                function implementation() public view returns (address) {
                    return getAppBase(appId());
                }
            
                /**
                 * @dev ERC897, whether it is a forwarding (1) or an upgradeable (2) proxy
                 */
                function proxyType() public pure returns (uint256 proxyTypeId) {
                    return UPGRADEABLE;
                }
            }
            
            // File: contracts/apps/AppProxyPinned.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            
            contract AppProxyPinned is IsContract, AppProxyBase {
                using UnstructuredStorage for bytes32;
            
                // keccak256("aragonOS.appStorage.pinnedCode")
                bytes32 internal constant PINNED_CODE_POSITION = 0xdee64df20d65e53d7f51cb6ab6d921a0a6a638a91e942e1d8d02df28e31c038e;
            
                /**
                * @dev Initialize AppProxyPinned (makes it an un-upgradeable Aragon app)
                * @param _kernel Reference to organization kernel for the app
                * @param _appId Identifier for app
                * @param _initializePayload Payload for call to be made after setup to initialize
                */
                constructor(IKernel _kernel, bytes32 _appId, bytes _initializePayload)
                    AppProxyBase(_kernel, _appId, _initializePayload)
                    public // solium-disable-line visibility-first
                {
                    setPinnedCode(getAppBase(_appId));
                    require(isContract(pinnedCode()));
                }
            
                /**
                 * @dev ERC897, the address the proxy would delegate calls to
                 */
                function implementation() public view returns (address) {
                    return pinnedCode();
                }
            
                /**
                 * @dev ERC897, whether it is a forwarding (1) or an upgradeable (2) proxy
                 */
                function proxyType() public pure returns (uint256 proxyTypeId) {
                    return FORWARDING;
                }
            
                function setPinnedCode(address _pinnedCode) internal {
                    PINNED_CODE_POSITION.setStorageAddress(_pinnedCode);
                }
            
                function pinnedCode() internal view returns (address) {
                    return PINNED_CODE_POSITION.getStorageAddress();
                }
            }
            
            // File: contracts/factory/AppProxyFactory.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            contract AppProxyFactory {
                event NewAppProxy(address proxy, bool isUpgradeable, bytes32 appId);
            
                /**
                * @notice Create a new upgradeable app instance on `_kernel` with identifier `_appId`
                * @param _kernel App's Kernel reference
                * @param _appId Identifier for app
                * @return AppProxyUpgradeable
                */
                function newAppProxy(IKernel _kernel, bytes32 _appId) public returns (AppProxyUpgradeable) {
                    return newAppProxy(_kernel, _appId, new bytes(0));
                }
            
                /**
                * @notice Create a new upgradeable app instance on `_kernel` with identifier `_appId` and initialization payload `_initializePayload`
                * @param _kernel App's Kernel reference
                * @param _appId Identifier for app
                * @return AppProxyUpgradeable
                */
                function newAppProxy(IKernel _kernel, bytes32 _appId, bytes _initializePayload) public returns (AppProxyUpgradeable) {
                    AppProxyUpgradeable proxy = new AppProxyUpgradeable(_kernel, _appId, _initializePayload);
                    emit NewAppProxy(address(proxy), true, _appId);
                    return proxy;
                }
            
                /**
                * @notice Create a new pinned app instance on `_kernel` with identifier `_appId`
                * @param _kernel App's Kernel reference
                * @param _appId Identifier for app
                * @return AppProxyPinned
                */
                function newAppProxyPinned(IKernel _kernel, bytes32 _appId) public returns (AppProxyPinned) {
                    return newAppProxyPinned(_kernel, _appId, new bytes(0));
                }
            
                /**
                * @notice Create a new pinned app instance on `_kernel` with identifier `_appId` and initialization payload `_initializePayload`
                * @param _kernel App's Kernel reference
                * @param _appId Identifier for app
                * @param _initializePayload Proxy initialization payload
                * @return AppProxyPinned
                */
                function newAppProxyPinned(IKernel _kernel, bytes32 _appId, bytes _initializePayload) public returns (AppProxyPinned) {
                    AppProxyPinned proxy = new AppProxyPinned(_kernel, _appId, _initializePayload);
                    emit NewAppProxy(address(proxy), false, _appId);
                    return proxy;
                }
            }
            
            // File: contracts/kernel/Kernel.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            
            
            
            
            
            
            
            
            
            // solium-disable-next-line max-len
            contract Kernel is IKernel, KernelStorage, KernelAppIds, KernelNamespaceConstants, Petrifiable, IsContract, VaultRecoverable, AppProxyFactory, ACLSyntaxSugar {
                /* Hardcoded constants to save gas
                bytes32 public constant APP_MANAGER_ROLE = keccak256("APP_MANAGER_ROLE");
                */
                bytes32 public constant APP_MANAGER_ROLE = 0xb6d92708f3d4817afc106147d969e229ced5c46e65e0a5002a0d391287762bd0;
            
                string private constant ERROR_APP_NOT_CONTRACT = "KERNEL_APP_NOT_CONTRACT";
                string private constant ERROR_INVALID_APP_CHANGE = "KERNEL_INVALID_APP_CHANGE";
                string private constant ERROR_AUTH_FAILED = "KERNEL_AUTH_FAILED";
            
                /**
                * @dev Constructor that allows the deployer to choose if the base instance should be petrified immediately.
                * @param _shouldPetrify Immediately petrify this instance so that it can never be initialized
                */
                constructor(bool _shouldPetrify) public {
                    if (_shouldPetrify) {
                        petrify();
                    }
                }
            
                /**
                * @dev Initialize can only be called once. It saves the block number in which it was initialized.
                * @notice Initialize this kernel instance along with its ACL and set `_permissionsCreator` as the entity that can create other permissions
                * @param _baseAcl Address of base ACL app
                * @param _permissionsCreator Entity that will be given permission over createPermission
                */
                function initialize(IACL _baseAcl, address _permissionsCreator) public onlyInit {
                    initialized();
            
                    // Set ACL base
                    _setApp(KERNEL_APP_BASES_NAMESPACE, KERNEL_DEFAULT_ACL_APP_ID, _baseAcl);
            
                    // Create ACL instance and attach it as the default ACL app
                    IACL acl = IACL(newAppProxy(this, KERNEL_DEFAULT_ACL_APP_ID));
                    acl.initialize(_permissionsCreator);
                    _setApp(KERNEL_APP_ADDR_NAMESPACE, KERNEL_DEFAULT_ACL_APP_ID, acl);
            
                    recoveryVaultAppId = KERNEL_DEFAULT_VAULT_APP_ID;
                }
            
                /**
                * @dev Create a new instance of an app linked to this kernel
                * @notice Create a new upgradeable instance of `_appId` app linked to the Kernel, setting its code to `_appBase`
                * @param _appId Identifier for app
                * @param _appBase Address of the app's base implementation
                * @return AppProxy instance
                */
                function newAppInstance(bytes32 _appId, address _appBase)
                    public
                    auth(APP_MANAGER_ROLE, arr(KERNEL_APP_BASES_NAMESPACE, _appId))
                    returns (ERCProxy appProxy)
                {
                    return newAppInstance(_appId, _appBase, new bytes(0), false);
                }
            
                /**
                * @dev Create a new instance of an app linked to this kernel and set its base
                *      implementation if it was not already set
                * @notice Create a new upgradeable instance of `_appId` app linked to the Kernel, setting its code to `_appBase`. `_setDefault ? 'Also sets it as the default app instance.':''`
                * @param _appId Identifier for app
                * @param _appBase Address of the app's base implementation
                * @param _initializePayload Payload for call made by the proxy during its construction to initialize
                * @param _setDefault Whether the app proxy app is the default one.
                *        Useful when the Kernel needs to know of an instance of a particular app,
                *        like Vault for escape hatch mechanism.
                * @return AppProxy instance
                */
                function newAppInstance(bytes32 _appId, address _appBase, bytes _initializePayload, bool _setDefault)
                    public
                    auth(APP_MANAGER_ROLE, arr(KERNEL_APP_BASES_NAMESPACE, _appId))
                    returns (ERCProxy appProxy)
                {
                    _setAppIfNew(KERNEL_APP_BASES_NAMESPACE, _appId, _appBase);
                    appProxy = newAppProxy(this, _appId, _initializePayload);
                    // By calling setApp directly and not the internal functions, we make sure the params are checked
                    // and it will only succeed if sender has permissions to set something to the namespace.
                    if (_setDefault) {
                        setApp(KERNEL_APP_ADDR_NAMESPACE, _appId, appProxy);
                    }
                }
            
                /**
                * @dev Create a new pinned instance of an app linked to this kernel
                * @notice Create a new non-upgradeable instance of `_appId` app linked to the Kernel, setting its code to `_appBase`.
                * @param _appId Identifier for app
                * @param _appBase Address of the app's base implementation
                * @return AppProxy instance
                */
                function newPinnedAppInstance(bytes32 _appId, address _appBase)
                    public
                    auth(APP_MANAGER_ROLE, arr(KERNEL_APP_BASES_NAMESPACE, _appId))
                    returns (ERCProxy appProxy)
                {
                    return newPinnedAppInstance(_appId, _appBase, new bytes(0), false);
                }
            
                /**
                * @dev Create a new pinned instance of an app linked to this kernel and set
                *      its base implementation if it was not already set
                * @notice Create a new non-upgradeable instance of `_appId` app linked to the Kernel, setting its code to `_appBase`. `_setDefault ? 'Also sets it as the default app instance.':''`
                * @param _appId Identifier for app
                * @param _appBase Address of the app's base implementation
                * @param _initializePayload Payload for call made by the proxy during its construction to initialize
                * @param _setDefault Whether the app proxy app is the default one.
                *        Useful when the Kernel needs to know of an instance of a particular app,
                *        like Vault for escape hatch mechanism.
                * @return AppProxy instance
                */
                function newPinnedAppInstance(bytes32 _appId, address _appBase, bytes _initializePayload, bool _setDefault)
                    public
                    auth(APP_MANAGER_ROLE, arr(KERNEL_APP_BASES_NAMESPACE, _appId))
                    returns (ERCProxy appProxy)
                {
                    _setAppIfNew(KERNEL_APP_BASES_NAMESPACE, _appId, _appBase);
                    appProxy = newAppProxyPinned(this, _appId, _initializePayload);
                    // By calling setApp directly and not the internal functions, we make sure the params are checked
                    // and it will only succeed if sender has permissions to set something to the namespace.
                    if (_setDefault) {
                        setApp(KERNEL_APP_ADDR_NAMESPACE, _appId, appProxy);
                    }
                }
            
                /**
                * @dev Set the resolving address of an app instance or base implementation
                * @notice Set the resolving address of `_appId` in namespace `_namespace` to `_app`
                * @param _namespace App namespace to use
                * @param _appId Identifier for app
                * @param _app Address of the app instance or base implementation
                * @return ID of app
                */
                function setApp(bytes32 _namespace, bytes32 _appId, address _app)
                    public
                    auth(APP_MANAGER_ROLE, arr(_namespace, _appId))
                {
                    _setApp(_namespace, _appId, _app);
                }
            
                /**
                * @dev Set the default vault id for the escape hatch mechanism
                * @param _recoveryVaultAppId Identifier of the recovery vault app
                */
                function setRecoveryVaultAppId(bytes32 _recoveryVaultAppId)
                    public
                    auth(APP_MANAGER_ROLE, arr(KERNEL_APP_ADDR_NAMESPACE, _recoveryVaultAppId))
                {
                    recoveryVaultAppId = _recoveryVaultAppId;
                }
            
                // External access to default app id and namespace constants to mimic default getters for constants
                /* solium-disable function-order, mixedcase */
                function CORE_NAMESPACE() external pure returns (bytes32) { return KERNEL_CORE_NAMESPACE; }
                function APP_BASES_NAMESPACE() external pure returns (bytes32) { return KERNEL_APP_BASES_NAMESPACE; }
                function APP_ADDR_NAMESPACE() external pure returns (bytes32) { return KERNEL_APP_ADDR_NAMESPACE; }
                function KERNEL_APP_ID() external pure returns (bytes32) { return KERNEL_CORE_APP_ID; }
                function DEFAULT_ACL_APP_ID() external pure returns (bytes32) { return KERNEL_DEFAULT_ACL_APP_ID; }
                /* solium-enable function-order, mixedcase */
            
                /**
                * @dev Get the address of an app instance or base implementation
                * @param _namespace App namespace to use
                * @param _appId Identifier for app
                * @return Address of the app
                */
                function getApp(bytes32 _namespace, bytes32 _appId) public view returns (address) {
                    return apps[_namespace][_appId];
                }
            
                /**
                * @dev Get the address of the recovery Vault instance (to recover funds)
                * @return Address of the Vault
                */
                function getRecoveryVault() public view returns (address) {
                    return apps[KERNEL_APP_ADDR_NAMESPACE][recoveryVaultAppId];
                }
            
                /**
                * @dev Get the installed ACL app
                * @return ACL app
                */
                function acl() public view returns (IACL) {
                    return IACL(getApp(KERNEL_APP_ADDR_NAMESPACE, KERNEL_DEFAULT_ACL_APP_ID));
                }
            
                /**
                * @dev Function called by apps to check ACL on kernel or to check permission status
                * @param _who Sender of the original call
                * @param _where Address of the app
                * @param _what Identifier for a group of actions in app
                * @param _how Extra data for ACL auth
                * @return Boolean indicating whether the ACL allows the role or not.
                *         Always returns false if the kernel hasn't been initialized yet.
                */
                function hasPermission(address _who, address _where, bytes32 _what, bytes _how) public view returns (bool) {
                    IACL defaultAcl = acl();
                    return address(defaultAcl) != address(0) && // Poor man's initialization check (saves gas)
                        defaultAcl.hasPermission(_who, _where, _what, _how);
                }
            
                function _setApp(bytes32 _namespace, bytes32 _appId, address _app) internal {
                    require(isContract(_app), ERROR_APP_NOT_CONTRACT);
                    apps[_namespace][_appId] = _app;
                    emit SetApp(_namespace, _appId, _app);
                }
            
                function _setAppIfNew(bytes32 _namespace, bytes32 _appId, address _app) internal {
                    address app = getApp(_namespace, _appId);
                    if (app != address(0)) {
                        // The only way to set an app is if it passes the isContract check, so no need to check it again
                        require(app == _app, ERROR_INVALID_APP_CHANGE);
                    } else {
                        _setApp(_namespace, _appId, _app);
                    }
                }
            
                modifier auth(bytes32 _role, uint256[] memory _params) {
                    require(
                        hasPermission(msg.sender, address(this), _role, ConversionHelpers.dangerouslyCastUintArrayToBytes(_params)),
                        ERROR_AUTH_FAILED
                    );
                    _;
                }
            }
            
            // File: contracts/kernel/KernelProxy.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            
            
            
            contract KernelProxy is IKernelEvents, KernelStorage, KernelAppIds, KernelNamespaceConstants, IsContract, DepositableDelegateProxy {
                /**
                * @dev KernelProxy is a proxy contract to a kernel implementation. The implementation
                *      can update the reference, which effectively upgrades the contract
                * @param _kernelImpl Address of the contract used as implementation for kernel
                */
                constructor(IKernel _kernelImpl) public {
                    require(isContract(address(_kernelImpl)));
                    apps[KERNEL_CORE_NAMESPACE][KERNEL_CORE_APP_ID] = _kernelImpl;
            
                    // Note that emitting this event is important for verifying that a KernelProxy instance
                    // was never upgraded to a malicious Kernel logic contract over its lifespan.
                    // This starts the "chain of trust", that can be followed through later SetApp() events
                    // emitted during kernel upgrades.
                    emit SetApp(KERNEL_CORE_NAMESPACE, KERNEL_CORE_APP_ID, _kernelImpl);
                }
            
                /**
                 * @dev ERC897, whether it is a forwarding (1) or an upgradeable (2) proxy
                 */
                function proxyType() public pure returns (uint256 proxyTypeId) {
                    return UPGRADEABLE;
                }
            
                /**
                * @dev ERC897, the address the proxy would delegate calls to
                */
                function implementation() public view returns (address) {
                    return apps[KERNEL_CORE_NAMESPACE][KERNEL_CORE_APP_ID];
                }
            }
            
            // File: contracts/common/Autopetrified.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            contract Autopetrified is Petrifiable {
                constructor() public {
                    // Immediately petrify base (non-proxy) instances of inherited contracts on deploy.
                    // This renders them uninitializable (and unusable without a proxy).
                    petrify();
                }
            }
            
            // File: contracts/common/ReentrancyGuard.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            contract ReentrancyGuard {
                using UnstructuredStorage for bytes32;
            
                /* Hardcoded constants to save gas
                bytes32 internal constant REENTRANCY_MUTEX_POSITION = keccak256("aragonOS.reentrancyGuard.mutex");
                */
                bytes32 private constant REENTRANCY_MUTEX_POSITION = 0xe855346402235fdd185c890e68d2c4ecad599b88587635ee285bce2fda58dacb;
            
                string private constant ERROR_REENTRANT = "REENTRANCY_REENTRANT_CALL";
            
                modifier nonReentrant() {
                    // Ensure mutex is unlocked
                    require(!REENTRANCY_MUTEX_POSITION.getStorageBool(), ERROR_REENTRANT);
            
                    // Lock mutex before function call
                    REENTRANCY_MUTEX_POSITION.setStorageBool(true);
            
                    // Perform function call
                    _;
            
                    // Unlock mutex after function call
                    REENTRANCY_MUTEX_POSITION.setStorageBool(false);
                }
            }
            
            // File: contracts/evmscript/IEVMScriptExecutor.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            interface IEVMScriptExecutor {
                function execScript(bytes script, bytes input, address[] blacklist) external returns (bytes);
                function executorType() external pure returns (bytes32);
            }
            
            // File: contracts/evmscript/IEVMScriptRegistry.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            contract EVMScriptRegistryConstants {
                /* Hardcoded constants to save gas
                bytes32 internal constant EVMSCRIPT_REGISTRY_APP_ID = apmNamehash("evmreg");
                */
                bytes32 internal constant EVMSCRIPT_REGISTRY_APP_ID = 0xddbcfd564f642ab5627cf68b9b7d374fb4f8a36e941a75d89c87998cef03bd61;
            }
            
            
            interface IEVMScriptRegistry {
                function addScriptExecutor(IEVMScriptExecutor executor) external returns (uint id);
                function disableScriptExecutor(uint256 executorId) external;
            
                // TODO: this should be external
                // See https://github.com/ethereum/solidity/issues/4832
                function getScriptExecutor(bytes script) public view returns (IEVMScriptExecutor);
            }
            
            // File: contracts/evmscript/EVMScriptRunner.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            
            
            
            
            contract EVMScriptRunner is AppStorage, Initializable, EVMScriptRegistryConstants, KernelNamespaceConstants {
                string private constant ERROR_EXECUTOR_UNAVAILABLE = "EVMRUN_EXECUTOR_UNAVAILABLE";
                string private constant ERROR_PROTECTED_STATE_MODIFIED = "EVMRUN_PROTECTED_STATE_MODIFIED";
            
                /* This is manually crafted in assembly
                string private constant ERROR_EXECUTOR_INVALID_RETURN = "EVMRUN_EXECUTOR_INVALID_RETURN";
                */
            
                event ScriptResult(address indexed executor, bytes script, bytes input, bytes returnData);
            
                function getEVMScriptExecutor(bytes _script) public view returns (IEVMScriptExecutor) {
                    return IEVMScriptExecutor(getEVMScriptRegistry().getScriptExecutor(_script));
                }
            
                function getEVMScriptRegistry() public view returns (IEVMScriptRegistry) {
                    address registryAddr = kernel().getApp(KERNEL_APP_ADDR_NAMESPACE, EVMSCRIPT_REGISTRY_APP_ID);
                    return IEVMScriptRegistry(registryAddr);
                }
            
                function runScript(bytes _script, bytes _input, address[] _blacklist)
                    internal
                    isInitialized
                    protectState
                    returns (bytes)
                {
                    IEVMScriptExecutor executor = getEVMScriptExecutor(_script);
                    require(address(executor) != address(0), ERROR_EXECUTOR_UNAVAILABLE);
            
                    bytes4 sig = executor.execScript.selector;
                    bytes memory data = abi.encodeWithSelector(sig, _script, _input, _blacklist);
            
                    bytes memory output;
                    assembly {
                        let success := delegatecall(
                            gas,                // forward all gas
                            executor,           // address
                            add(data, 0x20),    // calldata start
                            mload(data),        // calldata length
                            0,                  // don't write output (we'll handle this ourselves)
                            0                   // don't write output
                        )
            
                        output := mload(0x40) // free mem ptr get
            
                        switch success
                        case 0 {
                            // If the call errored, forward its full error data
                            returndatacopy(output, 0, returndatasize)
                            revert(output, returndatasize)
                        }
                        default {
                            switch gt(returndatasize, 0x3f)
                            case 0 {
                                // Need at least 0x40 bytes returned for properly ABI-encoded bytes values,
                                // revert with "EVMRUN_EXECUTOR_INVALID_RETURN"
                                // See remix: doing a `revert("EVMRUN_EXECUTOR_INVALID_RETURN")` always results in
                                // this memory layout
                                mstore(output, 0x08c379a000000000000000000000000000000000000000000000000000000000)         // error identifier
                                mstore(add(output, 0x04), 0x0000000000000000000000000000000000000000000000000000000000000020) // starting offset
                                mstore(add(output, 0x24), 0x000000000000000000000000000000000000000000000000000000000000001e) // reason length
                                mstore(add(output, 0x44), 0x45564d52554e5f4558454355544f525f494e56414c49445f52455455524e0000) // reason
            
                                revert(output, 100) // 100 = 4 + 3 * 32 (error identifier + 3 words for the ABI encoded error)
                            }
                            default {
                                // Copy result
                                //
                                // Needs to perform an ABI decode for the expected `bytes` return type of
                                // `executor.execScript()` as solidity will automatically ABI encode the returned bytes as:
                                //    [ position of the first dynamic length return value = 0x20 (32 bytes) ]
                                //    [ output length (32 bytes) ]
                                //    [ output content (N bytes) ]
                                //
                                // Perform the ABI decode by ignoring the first 32 bytes of the return data
                                let copysize := sub(returndatasize, 0x20)
                                returndatacopy(output, 0x20, copysize)
            
                                mstore(0x40, add(output, copysize)) // free mem ptr set
                            }
                        }
                    }
            
                    emit ScriptResult(address(executor), _script, _input, output);
            
                    return output;
                }
            
                modifier protectState {
                    address preKernel = address(kernel());
                    bytes32 preAppId = appId();
                    _; // exec
                    require(address(kernel()) == preKernel, ERROR_PROTECTED_STATE_MODIFIED);
                    require(appId() == preAppId, ERROR_PROTECTED_STATE_MODIFIED);
                }
            }
            
            // File: contracts/apps/AragonApp.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            
            
            
            
            
            
            // Contracts inheriting from AragonApp are, by default, immediately petrified upon deployment so
            // that they can never be initialized.
            // Unless overriden, this behaviour enforces those contracts to be usable only behind an AppProxy.
            // ReentrancyGuard, EVMScriptRunner, and ACLSyntaxSugar are not directly used by this contract, but
            // are included so that they are automatically usable by subclassing contracts
            contract AragonApp is AppStorage, Autopetrified, VaultRecoverable, ReentrancyGuard, EVMScriptRunner, ACLSyntaxSugar {
                string private constant ERROR_AUTH_FAILED = "APP_AUTH_FAILED";
            
                modifier auth(bytes32 _role) {
                    require(canPerform(msg.sender, _role, new uint256[](0)), ERROR_AUTH_FAILED);
                    _;
                }
            
                modifier authP(bytes32 _role, uint256[] _params) {
                    require(canPerform(msg.sender, _role, _params), ERROR_AUTH_FAILED);
                    _;
                }
            
                /**
                * @dev Check whether an action can be performed by a sender for a particular role on this app
                * @param _sender Sender of the call
                * @param _role Role on this app
                * @param _params Permission params for the role
                * @return Boolean indicating whether the sender has the permissions to perform the action.
                *         Always returns false if the app hasn't been initialized yet.
                */
                function canPerform(address _sender, bytes32 _role, uint256[] _params) public view returns (bool) {
                    if (!hasInitialized()) {
                        return false;
                    }
            
                    IKernel linkedKernel = kernel();
                    if (address(linkedKernel) == address(0)) {
                        return false;
                    }
            
                    return linkedKernel.hasPermission(
                        _sender,
                        address(this),
                        _role,
                        ConversionHelpers.dangerouslyCastUintArrayToBytes(_params)
                    );
                }
            
                /**
                * @dev Get the recovery vault for the app
                * @return Recovery vault address for the app
                */
                function getRecoveryVault() public view returns (address) {
                    // Funds recovery via a vault is only available when used with a kernel
                    return kernel().getRecoveryVault(); // if kernel is not set, it will revert
                }
            }
            
            // File: contracts/acl/IACLOracle.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            interface IACLOracle {
                function canPerform(address who, address where, bytes32 what, uint256[] how) external view returns (bool);
            }
            
            // File: contracts/acl/ACL.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            
            
            
            
            /* solium-disable function-order */
            // Allow public initialize() to be first
            contract ACL is IACL, TimeHelpers, AragonApp, ACLHelpers {
                /* Hardcoded constants to save gas
                bytes32 public constant CREATE_PERMISSIONS_ROLE = keccak256("CREATE_PERMISSIONS_ROLE");
                */
                bytes32 public constant CREATE_PERMISSIONS_ROLE = 0x0b719b33c83b8e5d300c521cb8b54ae9bd933996a14bef8c2f4e0285d2d2400a;
            
                enum Op { NONE, EQ, NEQ, GT, LT, GTE, LTE, RET, NOT, AND, OR, XOR, IF_ELSE } // op types
            
                struct Param {
                    uint8 id;
                    uint8 op;
                    uint240 value; // even though value is an uint240 it can store addresses
                    // in the case of 32 byte hashes losing 2 bytes precision isn't a huge deal
                    // op and id take less than 1 byte each so it can be kept in 1 sstore
                }
            
                uint8 internal constant BLOCK_NUMBER_PARAM_ID = 200;
                uint8 internal constant TIMESTAMP_PARAM_ID    = 201;
                // 202 is unused
                uint8 internal constant ORACLE_PARAM_ID       = 203;
                uint8 internal constant LOGIC_OP_PARAM_ID     = 204;
                uint8 internal constant PARAM_VALUE_PARAM_ID  = 205;
                // TODO: Add execution times param type?
            
                /* Hardcoded constant to save gas
                bytes32 public constant EMPTY_PARAM_HASH = keccak256(uint256(0));
                */
                bytes32 public constant EMPTY_PARAM_HASH = 0x290decd9548b62a8d60345a988386fc84ba6bc95484008f6362f93160ef3e563;
                bytes32 public constant NO_PERMISSION = bytes32(0);
                address public constant ANY_ENTITY = address(-1);
                address public constant BURN_ENTITY = address(1); // address(0) is already used as "no permission manager"
            
                string private constant ERROR_AUTH_INIT_KERNEL = "ACL_AUTH_INIT_KERNEL";
                string private constant ERROR_AUTH_NO_MANAGER = "ACL_AUTH_NO_MANAGER";
                string private constant ERROR_EXISTENT_MANAGER = "ACL_EXISTENT_MANAGER";
            
                // Whether someone has a permission
                mapping (bytes32 => bytes32) internal permissions; // permissions hash => params hash
                mapping (bytes32 => Param[]) internal permissionParams; // params hash => params
            
                // Who is the manager of a permission
                mapping (bytes32 => address) internal permissionManager;
            
                event SetPermission(address indexed entity, address indexed app, bytes32 indexed role, bool allowed);
                event SetPermissionParams(address indexed entity, address indexed app, bytes32 indexed role, bytes32 paramsHash);
                event ChangePermissionManager(address indexed app, bytes32 indexed role, address indexed manager);
            
                modifier onlyPermissionManager(address _app, bytes32 _role) {
                    require(msg.sender == getPermissionManager(_app, _role), ERROR_AUTH_NO_MANAGER);
                    _;
                }
            
                modifier noPermissionManager(address _app, bytes32 _role) {
                    // only allow permission creation (or re-creation) when there is no manager
                    require(getPermissionManager(_app, _role) == address(0), ERROR_EXISTENT_MANAGER);
                    _;
                }
            
                /**
                * @dev Initialize can only be called once. It saves the block number in which it was initialized.
                * @notice Initialize an ACL instance and set `_permissionsCreator` as the entity that can create other permissions
                * @param _permissionsCreator Entity that will be given permission over createPermission
                */
                function initialize(address _permissionsCreator) public onlyInit {
                    initialized();
                    require(msg.sender == address(kernel()), ERROR_AUTH_INIT_KERNEL);
            
                    _createPermission(_permissionsCreator, this, CREATE_PERMISSIONS_ROLE, _permissionsCreator);
                }
            
                /**
                * @dev Creates a permission that wasn't previously set and managed.
                *      If a created permission is removed it is possible to reset it with createPermission.
                *      This is the **ONLY** way to create permissions and set managers to permissions that don't
                *      have a manager.
                *      In terms of the ACL being initialized, this function implicitly protects all the other
                *      state-changing external functions, as they all require the sender to be a manager.
                * @notice Create a new permission granting `_entity` the ability to perform actions requiring `_role` on `_app`, setting `_manager` as the permission's manager
                * @param _entity Address of the whitelisted entity that will be able to perform the role
                * @param _app Address of the app in which the role will be allowed (requires app to depend on kernel for ACL)
                * @param _role Identifier for the group of actions in app given access to perform
                * @param _manager Address of the entity that will be able to grant and revoke the permission further.
                */
                function createPermission(address _entity, address _app, bytes32 _role, address _manager)
                    external
                    auth(CREATE_PERMISSIONS_ROLE)
                    noPermissionManager(_app, _role)
                {
                    _createPermission(_entity, _app, _role, _manager);
                }
            
                /**
                * @dev Grants permission if allowed. This requires `msg.sender` to be the permission manager
                * @notice Grant `_entity` the ability to perform actions requiring `_role` on `_app`
                * @param _entity Address of the whitelisted entity that will be able to perform the role
                * @param _app Address of the app in which the role will be allowed (requires app to depend on kernel for ACL)
                * @param _role Identifier for the group of actions in app given access to perform
                */
                function grantPermission(address _entity, address _app, bytes32 _role)
                    external
                {
                    grantPermissionP(_entity, _app, _role, new uint256[](0));
                }
            
                /**
                * @dev Grants a permission with parameters if allowed. This requires `msg.sender` to be the permission manager
                * @notice Grant `_entity` the ability to perform actions requiring `_role` on `_app`
                * @param _entity Address of the whitelisted entity that will be able to perform the role
                * @param _app Address of the app in which the role will be allowed (requires app to depend on kernel for ACL)
                * @param _role Identifier for the group of actions in app given access to perform
                * @param _params Permission parameters
                */
                function grantPermissionP(address _entity, address _app, bytes32 _role, uint256[] _params)
                    public
                    onlyPermissionManager(_app, _role)
                {
                    bytes32 paramsHash = _params.length > 0 ? _saveParams(_params) : EMPTY_PARAM_HASH;
                    _setPermission(_entity, _app, _role, paramsHash);
                }
            
                /**
                * @dev Revokes permission if allowed. This requires `msg.sender` to be the the permission manager
                * @notice Revoke from `_entity` the ability to perform actions requiring `_role` on `_app`
                * @param _entity Address of the whitelisted entity to revoke access from
                * @param _app Address of the app in which the role will be revoked
                * @param _role Identifier for the group of actions in app being revoked
                */
                function revokePermission(address _entity, address _app, bytes32 _role)
                    external
                    onlyPermissionManager(_app, _role)
                {
                    _setPermission(_entity, _app, _role, NO_PERMISSION);
                }
            
                /**
                * @notice Set `_newManager` as the manager of `_role` in `_app`
                * @param _newManager Address for the new manager
                * @param _app Address of the app in which the permission management is being transferred
                * @param _role Identifier for the group of actions being transferred
                */
                function setPermissionManager(address _newManager, address _app, bytes32 _role)
                    external
                    onlyPermissionManager(_app, _role)
                {
                    _setPermissionManager(_newManager, _app, _role);
                }
            
                /**
                * @notice Remove the manager of `_role` in `_app`
                * @param _app Address of the app in which the permission is being unmanaged
                * @param _role Identifier for the group of actions being unmanaged
                */
                function removePermissionManager(address _app, bytes32 _role)
                    external
                    onlyPermissionManager(_app, _role)
                {
                    _setPermissionManager(address(0), _app, _role);
                }
            
                /**
                * @notice Burn non-existent `_role` in `_app`, so no modification can be made to it (grant, revoke, permission manager)
                * @param _app Address of the app in which the permission is being burned
                * @param _role Identifier for the group of actions being burned
                */
                function createBurnedPermission(address _app, bytes32 _role)
                    external
                    auth(CREATE_PERMISSIONS_ROLE)
                    noPermissionManager(_app, _role)
                {
                    _setPermissionManager(BURN_ENTITY, _app, _role);
                }
            
                /**
                * @notice Burn `_role` in `_app`, so no modification can be made to it (grant, revoke, permission manager)
                * @param _app Address of the app in which the permission is being burned
                * @param _role Identifier for the group of actions being burned
                */
                function burnPermissionManager(address _app, bytes32 _role)
                    external
                    onlyPermissionManager(_app, _role)
                {
                    _setPermissionManager(BURN_ENTITY, _app, _role);
                }
            
                /**
                 * @notice Get parameters for permission array length
                 * @param _entity Address of the whitelisted entity that will be able to perform the role
                 * @param _app Address of the app
                 * @param _role Identifier for a group of actions in app
                 * @return Length of the array
                 */
                function getPermissionParamsLength(address _entity, address _app, bytes32 _role) external view returns (uint) {
                    return permissionParams[permissions[permissionHash(_entity, _app, _role)]].length;
                }
            
                /**
                * @notice Get parameter for permission
                * @param _entity Address of the whitelisted entity that will be able to perform the role
                * @param _app Address of the app
                * @param _role Identifier for a group of actions in app
                * @param _index Index of parameter in the array
                * @return Parameter (id, op, value)
                */
                function getPermissionParam(address _entity, address _app, bytes32 _role, uint _index)
                    external
                    view
                    returns (uint8, uint8, uint240)
                {
                    Param storage param = permissionParams[permissions[permissionHash(_entity, _app, _role)]][_index];
                    return (param.id, param.op, param.value);
                }
            
                /**
                * @dev Get manager for permission
                * @param _app Address of the app
                * @param _role Identifier for a group of actions in app
                * @return address of the manager for the permission
                */
                function getPermissionManager(address _app, bytes32 _role) public view returns (address) {
                    return permissionManager[roleHash(_app, _role)];
                }
            
                /**
                * @dev Function called by apps to check ACL on kernel or to check permission statu
                * @param _who Sender of the original call
                * @param _where Address of the app
                * @param _where Identifier for a group of actions in app
                * @param _how Permission parameters
                * @return boolean indicating whether the ACL allows the role or not
                */
                function hasPermission(address _who, address _where, bytes32 _what, bytes memory _how) public view returns (bool) {
                    return hasPermission(_who, _where, _what, ConversionHelpers.dangerouslyCastBytesToUintArray(_how));
                }
            
                function hasPermission(address _who, address _where, bytes32 _what, uint256[] memory _how) public view returns (bool) {
                    bytes32 whoParams = permissions[permissionHash(_who, _where, _what)];
                    if (whoParams != NO_PERMISSION && evalParams(whoParams, _who, _where, _what, _how)) {
                        return true;
                    }
            
                    bytes32 anyParams = permissions[permissionHash(ANY_ENTITY, _where, _what)];
                    if (anyParams != NO_PERMISSION && evalParams(anyParams, ANY_ENTITY, _where, _what, _how)) {
                        return true;
                    }
            
                    return false;
                }
            
                function hasPermission(address _who, address _where, bytes32 _what) public view returns (bool) {
                    uint256[] memory empty = new uint256[](0);
                    return hasPermission(_who, _where, _what, empty);
                }
            
                function evalParams(
                    bytes32 _paramsHash,
                    address _who,
                    address _where,
                    bytes32 _what,
                    uint256[] _how
                ) public view returns (bool)
                {
                    if (_paramsHash == EMPTY_PARAM_HASH) {
                        return true;
                    }
            
                    return _evalParam(_paramsHash, 0, _who, _where, _what, _how);
                }
            
                /**
                * @dev Internal createPermission for access inside the kernel (on instantiation)
                */
                function _createPermission(address _entity, address _app, bytes32 _role, address _manager) internal {
                    _setPermission(_entity, _app, _role, EMPTY_PARAM_HASH);
                    _setPermissionManager(_manager, _app, _role);
                }
            
                /**
                * @dev Internal function called to actually save the permission
                */
                function _setPermission(address _entity, address _app, bytes32 _role, bytes32 _paramsHash) internal {
                    permissions[permissionHash(_entity, _app, _role)] = _paramsHash;
                    bool entityHasPermission = _paramsHash != NO_PERMISSION;
                    bool permissionHasParams = entityHasPermission && _paramsHash != EMPTY_PARAM_HASH;
            
                    emit SetPermission(_entity, _app, _role, entityHasPermission);
                    if (permissionHasParams) {
                        emit SetPermissionParams(_entity, _app, _role, _paramsHash);
                    }
                }
            
                function _saveParams(uint256[] _encodedParams) internal returns (bytes32) {
                    bytes32 paramHash = keccak256(abi.encodePacked(_encodedParams));
                    Param[] storage params = permissionParams[paramHash];
            
                    if (params.length == 0) { // params not saved before
                        for (uint256 i = 0; i < _encodedParams.length; i++) {
                            uint256 encodedParam = _encodedParams[i];
                            Param memory param = Param(decodeParamId(encodedParam), decodeParamOp(encodedParam), uint240(encodedParam));
                            params.push(param);
                        }
                    }
            
                    return paramHash;
                }
            
                function _evalParam(
                    bytes32 _paramsHash,
                    uint32 _paramId,
                    address _who,
                    address _where,
                    bytes32 _what,
                    uint256[] _how
                ) internal view returns (bool)
                {
                    if (_paramId >= permissionParams[_paramsHash].length) {
                        return false; // out of bounds
                    }
            
                    Param memory param = permissionParams[_paramsHash][_paramId];
            
                    if (param.id == LOGIC_OP_PARAM_ID) {
                        return _evalLogic(param, _paramsHash, _who, _where, _what, _how);
                    }
            
                    uint256 value;
                    uint256 comparedTo = uint256(param.value);
            
                    // get value
                    if (param.id == ORACLE_PARAM_ID) {
                        value = checkOracle(IACLOracle(param.value), _who, _where, _what, _how) ? 1 : 0;
                        comparedTo = 1;
                    } else if (param.id == BLOCK_NUMBER_PARAM_ID) {
                        value = getBlockNumber();
                    } else if (param.id == TIMESTAMP_PARAM_ID) {
                        value = getTimestamp();
                    } else if (param.id == PARAM_VALUE_PARAM_ID) {
                        value = uint256(param.value);
                    } else {
                        if (param.id >= _how.length) {
                            return false;
                        }
                        value = uint256(uint240(_how[param.id])); // force lost precision
                    }
            
                    if (Op(param.op) == Op.RET) {
                        return uint256(value) > 0;
                    }
            
                    return compare(value, Op(param.op), comparedTo);
                }
            
                function _evalLogic(Param _param, bytes32 _paramsHash, address _who, address _where, bytes32 _what, uint256[] _how)
                    internal
                    view
                    returns (bool)
                {
                    if (Op(_param.op) == Op.IF_ELSE) {
                        uint32 conditionParam;
                        uint32 successParam;
                        uint32 failureParam;
            
                        (conditionParam, successParam, failureParam) = decodeParamsList(uint256(_param.value));
                        bool result = _evalParam(_paramsHash, conditionParam, _who, _where, _what, _how);
            
                        return _evalParam(_paramsHash, result ? successParam : failureParam, _who, _where, _what, _how);
                    }
            
                    uint32 param1;
                    uint32 param2;
            
                    (param1, param2,) = decodeParamsList(uint256(_param.value));
                    bool r1 = _evalParam(_paramsHash, param1, _who, _where, _what, _how);
            
                    if (Op(_param.op) == Op.NOT) {
                        return !r1;
                    }
            
                    if (r1 && Op(_param.op) == Op.OR) {
                        return true;
                    }
            
                    if (!r1 && Op(_param.op) == Op.AND) {
                        return false;
                    }
            
                    bool r2 = _evalParam(_paramsHash, param2, _who, _where, _what, _how);
            
                    if (Op(_param.op) == Op.XOR) {
                        return r1 != r2;
                    }
            
                    return r2; // both or and and depend on result of r2 after checks
                }
            
                function compare(uint256 _a, Op _op, uint256 _b) internal pure returns (bool) {
                    if (_op == Op.EQ)  return _a == _b;                              // solium-disable-line lbrace
                    if (_op == Op.NEQ) return _a != _b;                              // solium-disable-line lbrace
                    if (_op == Op.GT)  return _a > _b;                               // solium-disable-line lbrace
                    if (_op == Op.LT)  return _a < _b;                               // solium-disable-line lbrace
                    if (_op == Op.GTE) return _a >= _b;                              // solium-disable-line lbrace
                    if (_op == Op.LTE) return _a <= _b;                              // solium-disable-line lbrace
                    return false;
                }
            
                function checkOracle(IACLOracle _oracleAddr, address _who, address _where, bytes32 _what, uint256[] _how) internal view returns (bool) {
                    bytes4 sig = _oracleAddr.canPerform.selector;
            
                    // a raw call is required so we can return false if the call reverts, rather than reverting
                    bytes memory checkCalldata = abi.encodeWithSelector(sig, _who, _where, _what, _how);
            
                    bool ok;
                    assembly {
                        // send all available gas; if the oracle eats up all the gas, we will eventually revert
                        // note that we are currently guaranteed to still have some gas after the call from
                        // EIP-150's 63/64 gas forward rule
                        ok := staticcall(gas, _oracleAddr, add(checkCalldata, 0x20), mload(checkCalldata), 0, 0)
                    }
            
                    if (!ok) {
                        return false;
                    }
            
                    uint256 size;
                    assembly { size := returndatasize }
                    if (size != 32) {
                        return false;
                    }
            
                    bool result;
                    assembly {
                        let ptr := mload(0x40)       // get next free memory ptr
                        returndatacopy(ptr, 0, size) // copy return from above `staticcall`
                        result := mload(ptr)         // read data at ptr and set it to result
                        mstore(ptr, 0)               // set pointer memory to 0 so it still is the next free ptr
                    }
            
                    return result;
                }
            
                /**
                * @dev Internal function that sets management
                */
                function _setPermissionManager(address _newManager, address _app, bytes32 _role) internal {
                    permissionManager[roleHash(_app, _role)] = _newManager;
                    emit ChangePermissionManager(_app, _role, _newManager);
                }
            
                function roleHash(address _where, bytes32 _what) internal pure returns (bytes32) {
                    return keccak256(abi.encodePacked("ROLE", _where, _what));
                }
            
                function permissionHash(address _who, address _where, bytes32 _what) internal pure returns (bytes32) {
                    return keccak256(abi.encodePacked("PERMISSION", _who, _where, _what));
                }
            }
            
            // File: contracts/evmscript/ScriptHelpers.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            library ScriptHelpers {
                function getSpecId(bytes _script) internal pure returns (uint32) {
                    return uint32At(_script, 0);
                }
            
                function uint256At(bytes _data, uint256 _location) internal pure returns (uint256 result) {
                    assembly {
                        result := mload(add(_data, add(0x20, _location)))
                    }
                }
            
                function addressAt(bytes _data, uint256 _location) internal pure returns (address result) {
                    uint256 word = uint256At(_data, _location);
            
                    assembly {
                        result := div(and(word, 0xffffffffffffffffffffffffffffffffffffffff000000000000000000000000),
                        0x1000000000000000000000000)
                    }
                }
            
                function uint32At(bytes _data, uint256 _location) internal pure returns (uint32 result) {
                    uint256 word = uint256At(_data, _location);
            
                    assembly {
                        result := div(and(word, 0xffffffff00000000000000000000000000000000000000000000000000000000),
                        0x100000000000000000000000000000000000000000000000000000000)
                    }
                }
            
                function locationOf(bytes _data, uint256 _location) internal pure returns (uint256 result) {
                    assembly {
                        result := add(_data, add(0x20, _location))
                    }
                }
            
                function toBytes(bytes4 _sig) internal pure returns (bytes) {
                    bytes memory payload = new bytes(4);
                    assembly { mstore(add(payload, 0x20), _sig) }
                    return payload;
                }
            }
            
            // File: contracts/evmscript/EVMScriptRegistry.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            
            
            /* solium-disable function-order */
            // Allow public initialize() to be first
            contract EVMScriptRegistry is IEVMScriptRegistry, EVMScriptRegistryConstants, AragonApp {
                using ScriptHelpers for bytes;
            
                /* Hardcoded constants to save gas
                bytes32 public constant REGISTRY_ADD_EXECUTOR_ROLE = keccak256("REGISTRY_ADD_EXECUTOR_ROLE");
                bytes32 public constant REGISTRY_MANAGER_ROLE = keccak256("REGISTRY_MANAGER_ROLE");
                */
                bytes32 public constant REGISTRY_ADD_EXECUTOR_ROLE = 0xc4e90f38eea8c4212a009ca7b8947943ba4d4a58d19b683417f65291d1cd9ed2;
                // WARN: Manager can censor all votes and the like happening in an org
                bytes32 public constant REGISTRY_MANAGER_ROLE = 0xf7a450ef335e1892cb42c8ca72e7242359d7711924b75db5717410da3f614aa3;
            
                uint256 internal constant SCRIPT_START_LOCATION = 4;
            
                string private constant ERROR_INEXISTENT_EXECUTOR = "EVMREG_INEXISTENT_EXECUTOR";
                string private constant ERROR_EXECUTOR_ENABLED = "EVMREG_EXECUTOR_ENABLED";
                string private constant ERROR_EXECUTOR_DISABLED = "EVMREG_EXECUTOR_DISABLED";
                string private constant ERROR_SCRIPT_LENGTH_TOO_SHORT = "EVMREG_SCRIPT_LENGTH_TOO_SHORT";
            
                struct ExecutorEntry {
                    IEVMScriptExecutor executor;
                    bool enabled;
                }
            
                uint256 private executorsNextIndex;
                mapping (uint256 => ExecutorEntry) public executors;
            
                event EnableExecutor(uint256 indexed executorId, address indexed executorAddress);
                event DisableExecutor(uint256 indexed executorId, address indexed executorAddress);
            
                modifier executorExists(uint256 _executorId) {
                    require(_executorId > 0 && _executorId < executorsNextIndex, ERROR_INEXISTENT_EXECUTOR);
                    _;
                }
            
                /**
                * @notice Initialize the registry
                */
                function initialize() public onlyInit {
                    initialized();
                    // Create empty record to begin executor IDs at 1
                    executorsNextIndex = 1;
                }
            
                /**
                * @notice Add a new script executor with address `_executor` to the registry
                * @param _executor Address of the IEVMScriptExecutor that will be added to the registry
                * @return id Identifier of the executor in the registry
                */
                function addScriptExecutor(IEVMScriptExecutor _executor) external auth(REGISTRY_ADD_EXECUTOR_ROLE) returns (uint256 id) {
                    uint256 executorId = executorsNextIndex++;
                    executors[executorId] = ExecutorEntry(_executor, true);
                    emit EnableExecutor(executorId, _executor);
                    return executorId;
                }
            
                /**
                * @notice Disable script executor with ID `_executorId`
                * @param _executorId Identifier of the executor in the registry
                */
                function disableScriptExecutor(uint256 _executorId)
                    external
                    authP(REGISTRY_MANAGER_ROLE, arr(_executorId))
                {
                    // Note that we don't need to check for an executor's existence in this case, as only
                    // existing executors can be enabled
                    ExecutorEntry storage executorEntry = executors[_executorId];
                    require(executorEntry.enabled, ERROR_EXECUTOR_DISABLED);
                    executorEntry.enabled = false;
                    emit DisableExecutor(_executorId, executorEntry.executor);
                }
            
                /**
                * @notice Enable script executor with ID `_executorId`
                * @param _executorId Identifier of the executor in the registry
                */
                function enableScriptExecutor(uint256 _executorId)
                    external
                    authP(REGISTRY_MANAGER_ROLE, arr(_executorId))
                    executorExists(_executorId)
                {
                    ExecutorEntry storage executorEntry = executors[_executorId];
                    require(!executorEntry.enabled, ERROR_EXECUTOR_ENABLED);
                    executorEntry.enabled = true;
                    emit EnableExecutor(_executorId, executorEntry.executor);
                }
            
                /**
                * @dev Get the script executor that can execute a particular script based on its first 4 bytes
                * @param _script EVMScript being inspected
                */
                function getScriptExecutor(bytes _script) public view returns (IEVMScriptExecutor) {
                    require(_script.length >= SCRIPT_START_LOCATION, ERROR_SCRIPT_LENGTH_TOO_SHORT);
                    uint256 id = _script.getSpecId();
            
                    // Note that we don't need to check for an executor's existence in this case, as only
                    // existing executors can be enabled
                    ExecutorEntry storage entry = executors[id];
                    return entry.enabled ? entry.executor : IEVMScriptExecutor(0);
                }
            }
            
            // File: contracts/evmscript/executors/BaseEVMScriptExecutor.sol
            
            /*
             * SPDX-License-Identifier:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            
            contract BaseEVMScriptExecutor is IEVMScriptExecutor, Autopetrified {
                uint256 internal constant SCRIPT_START_LOCATION = 4;
            }
            
            // File: contracts/evmscript/executors/CallsScript.sol
            
            pragma solidity 0.4.24;
            
            // Inspired by https://github.com/reverendus/tx-manager
            
            
            
            
            contract CallsScript is BaseEVMScriptExecutor {
                using ScriptHelpers for bytes;
            
                /* Hardcoded constants to save gas
                bytes32 internal constant EXECUTOR_TYPE = keccak256("CALLS_SCRIPT");
                */
                bytes32 internal constant EXECUTOR_TYPE = 0x2dc858a00f3e417be1394b87c07158e989ec681ce8cc68a9093680ac1a870302;
            
                string private constant ERROR_BLACKLISTED_CALL = "EVMCALLS_BLACKLISTED_CALL";
                string private constant ERROR_INVALID_LENGTH = "EVMCALLS_INVALID_LENGTH";
            
                /* This is manually crafted in assembly
                string private constant ERROR_CALL_REVERTED = "EVMCALLS_CALL_REVERTED";
                */
            
                event LogScriptCall(address indexed sender, address indexed src, address indexed dst);
            
                /**
                * @notice Executes a number of call scripts
                * @param _script [ specId (uint32) ] many calls with this structure ->
                *    [ to (address: 20 bytes) ] [ calldataLength (uint32: 4 bytes) ] [ calldata (calldataLength bytes) ]
                * @param _blacklist Addresses the script cannot call to, or will revert.
                * @return Always returns empty byte array
                */
                function execScript(bytes _script, bytes, address[] _blacklist) external isInitialized returns (bytes) {
                    uint256 location = SCRIPT_START_LOCATION; // first 32 bits are spec id
                    while (location < _script.length) {
                        // Check there's at least address + calldataLength available
                        require(_script.length - location >= 0x18, ERROR_INVALID_LENGTH);
            
                        address contractAddress = _script.addressAt(location);
                        // Check address being called is not blacklist
                        for (uint256 i = 0; i < _blacklist.length; i++) {
                            require(contractAddress != _blacklist[i], ERROR_BLACKLISTED_CALL);
                        }
            
                        // logged before execution to ensure event ordering in receipt
                        // if failed entire execution is reverted regardless
                        emit LogScriptCall(msg.sender, address(this), contractAddress);
            
                        uint256 calldataLength = uint256(_script.uint32At(location + 0x14));
                        uint256 startOffset = location + 0x14 + 0x04;
                        uint256 calldataStart = _script.locationOf(startOffset);
            
                        // compute end of script / next location
                        location = startOffset + calldataLength;
                        require(location <= _script.length, ERROR_INVALID_LENGTH);
            
                        bool success;
                        assembly {
                            success := call(
                                sub(gas, 5000),       // forward gas left - 5000
                                contractAddress,      // address
                                0,                    // no value
                                calldataStart,        // calldata start
                                calldataLength,       // calldata length
                                0,                    // don't write output
                                0                     // don't write output
                            )
            
                            switch success
                            case 0 {
                                let ptr := mload(0x40)
            
                                switch returndatasize
                                case 0 {
                                    // No error data was returned, revert with "EVMCALLS_CALL_REVERTED"
                                    // See remix: doing a `revert("EVMCALLS_CALL_REVERTED")` always results in
                                    // this memory layout
                                    mstore(ptr, 0x08c379a000000000000000000000000000000000000000000000000000000000)         // error identifier
                                    mstore(add(ptr, 0x04), 0x0000000000000000000000000000000000000000000000000000000000000020) // starting offset
                                    mstore(add(ptr, 0x24), 0x0000000000000000000000000000000000000000000000000000000000000016) // reason length
                                    mstore(add(ptr, 0x44), 0x45564d43414c4c535f43414c4c5f524556455254454400000000000000000000) // reason
            
                                    revert(ptr, 100) // 100 = 4 + 3 * 32 (error identifier + 3 words for the ABI encoded error)
                                }
                                default {
                                    // Forward the full error data
                                    returndatacopy(ptr, 0, returndatasize)
                                    revert(ptr, returndatasize)
                                }
                            }
                            default { }
                        }
                    }
                    // No need to allocate empty bytes for the return as this can only be called via an delegatecall
                    // (due to the isInitialized modifier)
                }
            
                function executorType() external pure returns (bytes32) {
                    return EXECUTOR_TYPE;
                }
            }
            
            // File: contracts/factory/EVMScriptRegistryFactory.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            
            
            
            contract EVMScriptRegistryFactory is EVMScriptRegistryConstants {
                EVMScriptRegistry public baseReg;
                IEVMScriptExecutor public baseCallScript;
            
                /**
                * @notice Create a new EVMScriptRegistryFactory.
                */
                constructor() public {
                    baseReg = new EVMScriptRegistry();
                    baseCallScript = IEVMScriptExecutor(new CallsScript());
                }
            
                /**
                * @notice Install a new pinned instance of EVMScriptRegistry on `_dao`.
                * @param _dao Kernel
                * @return Installed EVMScriptRegistry
                */
                function newEVMScriptRegistry(Kernel _dao) public returns (EVMScriptRegistry reg) {
                    bytes memory initPayload = abi.encodeWithSelector(reg.initialize.selector);
                    reg = EVMScriptRegistry(_dao.newPinnedAppInstance(EVMSCRIPT_REGISTRY_APP_ID, baseReg, initPayload, true));
            
                    ACL acl = ACL(_dao.acl());
            
                    acl.createPermission(this, reg, reg.REGISTRY_ADD_EXECUTOR_ROLE(), this);
            
                    reg.addScriptExecutor(baseCallScript);     // spec 1 = CallsScript
            
                    // Clean up the permissions
                    acl.revokePermission(this, reg, reg.REGISTRY_ADD_EXECUTOR_ROLE());
                    acl.removePermissionManager(reg, reg.REGISTRY_ADD_EXECUTOR_ROLE());
            
                    return reg;
                }
            }
            
            // File: contracts/factory/DAOFactory.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            
            
            
            
            contract DAOFactory {
                IKernel public baseKernel;
                IACL public baseACL;
                EVMScriptRegistryFactory public regFactory;
            
                event DeployDAO(address dao);
                event DeployEVMScriptRegistry(address reg);
            
                /**
                * @notice Create a new DAOFactory, creating DAOs with Kernels proxied to `_baseKernel`, ACLs proxied to `_baseACL`, and new EVMScriptRegistries created from `_regFactory`.
                * @param _baseKernel Base Kernel
                * @param _baseACL Base ACL
                * @param _regFactory EVMScriptRegistry factory
                */
                constructor(IKernel _baseKernel, IACL _baseACL, EVMScriptRegistryFactory _regFactory) public {
                    // No need to init as it cannot be killed by devops199
                    if (address(_regFactory) != address(0)) {
                        regFactory = _regFactory;
                    }
            
                    baseKernel = _baseKernel;
                    baseACL = _baseACL;
                }
            
                /**
                * @notice Create a new DAO with `_root` set as the initial admin
                * @param _root Address that will be granted control to setup DAO permissions
                * @return Newly created DAO
                */
                function newDAO(address _root) public returns (Kernel) {
                    Kernel dao = Kernel(new KernelProxy(baseKernel));
            
                    if (address(regFactory) == address(0)) {
                        dao.initialize(baseACL, _root);
                    } else {
                        dao.initialize(baseACL, this);
            
                        ACL acl = ACL(dao.acl());
                        bytes32 permRole = acl.CREATE_PERMISSIONS_ROLE();
                        bytes32 appManagerRole = dao.APP_MANAGER_ROLE();
            
                        acl.grantPermission(regFactory, acl, permRole);
            
                        acl.createPermission(regFactory, dao, appManagerRole, this);
            
                        EVMScriptRegistry reg = regFactory.newEVMScriptRegistry(dao);
                        emit DeployEVMScriptRegistry(address(reg));
            
                        // Clean up permissions
                        // First, completely reset the APP_MANAGER_ROLE
                        acl.revokePermission(regFactory, dao, appManagerRole);
                        acl.removePermissionManager(dao, appManagerRole);
            
                        // Then, make root the only holder and manager of CREATE_PERMISSIONS_ROLE
                        acl.revokePermission(regFactory, acl, permRole);
                        acl.revokePermission(this, acl, permRole);
                        acl.grantPermission(_root, acl, permRole);
                        acl.setPermissionManager(_root, acl, permRole);
                    }
            
                    emit DeployDAO(address(dao));
            
                    return dao;
                }
            }

            File 4 of 5: Kernel
            // File: contracts/acl/IACL.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            interface IACL {
                function initialize(address permissionsCreator) external;
            
                // TODO: this should be external
                // See https://github.com/ethereum/solidity/issues/4832
                function hasPermission(address who, address where, bytes32 what, bytes how) public view returns (bool);
            }
            
            // File: contracts/common/IVaultRecoverable.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            interface IVaultRecoverable {
                event RecoverToVault(address indexed vault, address indexed token, uint256 amount);
            
                function transferToVault(address token) external;
            
                function allowRecoverability(address token) external view returns (bool);
                function getRecoveryVault() external view returns (address);
            }
            
            // File: contracts/kernel/IKernel.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            
            interface IKernelEvents {
                event SetApp(bytes32 indexed namespace, bytes32 indexed appId, address app);
            }
            
            
            // This should be an interface, but interfaces can't inherit yet :(
            contract IKernel is IKernelEvents, IVaultRecoverable {
                function acl() public view returns (IACL);
                function hasPermission(address who, address where, bytes32 what, bytes how) public view returns (bool);
            
                function setApp(bytes32 namespace, bytes32 appId, address app) public;
                function getApp(bytes32 namespace, bytes32 appId) public view returns (address);
            }
            
            // File: contracts/kernel/KernelConstants.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            contract KernelAppIds {
                /* Hardcoded constants to save gas
                bytes32 internal constant KERNEL_CORE_APP_ID = apmNamehash("kernel");
                bytes32 internal constant KERNEL_DEFAULT_ACL_APP_ID = apmNamehash("acl");
                bytes32 internal constant KERNEL_DEFAULT_VAULT_APP_ID = apmNamehash("vault");
                */
                bytes32 internal constant KERNEL_CORE_APP_ID = 0x3b4bf6bf3ad5000ecf0f989d5befde585c6860fea3e574a4fab4c49d1c177d9c;
                bytes32 internal constant KERNEL_DEFAULT_ACL_APP_ID = 0xe3262375f45a6e2026b7e7b18c2b807434f2508fe1a2a3dfb493c7df8f4aad6a;
                bytes32 internal constant KERNEL_DEFAULT_VAULT_APP_ID = 0x7e852e0fcfce6551c13800f1e7476f982525c2b5277ba14b24339c68416336d1;
            }
            
            
            contract KernelNamespaceConstants {
                /* Hardcoded constants to save gas
                bytes32 internal constant KERNEL_CORE_NAMESPACE = keccak256("core");
                bytes32 internal constant KERNEL_APP_BASES_NAMESPACE = keccak256("base");
                bytes32 internal constant KERNEL_APP_ADDR_NAMESPACE = keccak256("app");
                */
                bytes32 internal constant KERNEL_CORE_NAMESPACE = 0xc681a85306374a5ab27f0bbc385296a54bcd314a1948b6cf61c4ea1bc44bb9f8;
                bytes32 internal constant KERNEL_APP_BASES_NAMESPACE = 0xf1f3eb40f5bc1ad1344716ced8b8a0431d840b5783aea1fd01786bc26f35ac0f;
                bytes32 internal constant KERNEL_APP_ADDR_NAMESPACE = 0xd6f028ca0e8edb4a8c9757ca4fdccab25fa1e0317da1188108f7d2dee14902fb;
            }
            
            // File: contracts/kernel/KernelStorage.sol
            
            pragma solidity 0.4.24;
            
            
            contract KernelStorage {
                // namespace => app id => address
                mapping (bytes32 => mapping (bytes32 => address)) public apps;
                bytes32 public recoveryVaultAppId;
            }
            
            // File: contracts/acl/ACLSyntaxSugar.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            contract ACLSyntaxSugar {
                function arr() internal pure returns (uint256[]) {
                    return new uint256[](0);
                }
            
                function arr(bytes32 _a) internal pure returns (uint256[] r) {
                    return arr(uint256(_a));
                }
            
                function arr(bytes32 _a, bytes32 _b) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b));
                }
            
                function arr(address _a) internal pure returns (uint256[] r) {
                    return arr(uint256(_a));
                }
            
                function arr(address _a, address _b) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b));
                }
            
                function arr(address _a, uint256 _b, uint256 _c) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), _b, _c);
                }
            
                function arr(address _a, uint256 _b, uint256 _c, uint256 _d) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), _b, _c, _d);
                }
            
                function arr(address _a, uint256 _b) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b));
                }
            
                function arr(address _a, address _b, uint256 _c, uint256 _d, uint256 _e) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b), _c, _d, _e);
                }
            
                function arr(address _a, address _b, address _c) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b), uint256(_c));
                }
            
                function arr(address _a, address _b, uint256 _c) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b), uint256(_c));
                }
            
                function arr(uint256 _a) internal pure returns (uint256[] r) {
                    r = new uint256[](1);
                    r[0] = _a;
                }
            
                function arr(uint256 _a, uint256 _b) internal pure returns (uint256[] r) {
                    r = new uint256[](2);
                    r[0] = _a;
                    r[1] = _b;
                }
            
                function arr(uint256 _a, uint256 _b, uint256 _c) internal pure returns (uint256[] r) {
                    r = new uint256[](3);
                    r[0] = _a;
                    r[1] = _b;
                    r[2] = _c;
                }
            
                function arr(uint256 _a, uint256 _b, uint256 _c, uint256 _d) internal pure returns (uint256[] r) {
                    r = new uint256[](4);
                    r[0] = _a;
                    r[1] = _b;
                    r[2] = _c;
                    r[3] = _d;
                }
            
                function arr(uint256 _a, uint256 _b, uint256 _c, uint256 _d, uint256 _e) internal pure returns (uint256[] r) {
                    r = new uint256[](5);
                    r[0] = _a;
                    r[1] = _b;
                    r[2] = _c;
                    r[3] = _d;
                    r[4] = _e;
                }
            }
            
            
            contract ACLHelpers {
                function decodeParamOp(uint256 _x) internal pure returns (uint8 b) {
                    return uint8(_x >> (8 * 30));
                }
            
                function decodeParamId(uint256 _x) internal pure returns (uint8 b) {
                    return uint8(_x >> (8 * 31));
                }
            
                function decodeParamsList(uint256 _x) internal pure returns (uint32 a, uint32 b, uint32 c) {
                    a = uint32(_x);
                    b = uint32(_x >> (8 * 4));
                    c = uint32(_x >> (8 * 8));
                }
            }
            
            // File: contracts/common/ConversionHelpers.sol
            
            pragma solidity ^0.4.24;
            
            
            library ConversionHelpers {
                string private constant ERROR_IMPROPER_LENGTH = "CONVERSION_IMPROPER_LENGTH";
            
                function dangerouslyCastUintArrayToBytes(uint256[] memory _input) internal pure returns (bytes memory output) {
                    // Force cast the uint256[] into a bytes array, by overwriting its length
                    // Note that the bytes array doesn't need to be initialized as we immediately overwrite it
                    // with the input and a new length. The input becomes invalid from this point forward.
                    uint256 byteLength = _input.length * 32;
                    assembly {
                        output := _input
                        mstore(output, byteLength)
                    }
                }
            
                function dangerouslyCastBytesToUintArray(bytes memory _input) internal pure returns (uint256[] memory output) {
                    // Force cast the bytes array into a uint256[], by overwriting its length
                    // Note that the uint256[] doesn't need to be initialized as we immediately overwrite it
                    // with the input and a new length. The input becomes invalid from this point forward.
                    uint256 intsLength = _input.length / 32;
                    require(_input.length == intsLength * 32, ERROR_IMPROPER_LENGTH);
            
                    assembly {
                        output := _input
                        mstore(output, intsLength)
                    }
                }
            }
            
            // File: contracts/common/IsContract.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            contract IsContract {
                /*
                * NOTE: this should NEVER be used for authentication
                * (see pitfalls: https://github.com/fergarrui/ethereum-security/tree/master/contracts/extcodesize).
                *
                * This is only intended to be used as a sanity check that an address is actually a contract,
                * RATHER THAN an address not being a contract.
                */
                function isContract(address _target) internal view returns (bool) {
                    if (_target == address(0)) {
                        return false;
                    }
            
                    uint256 size;
                    assembly { size := extcodesize(_target) }
                    return size > 0;
                }
            }
            
            // File: contracts/common/Uint256Helpers.sol
            
            pragma solidity ^0.4.24;
            
            
            library Uint256Helpers {
                uint256 private constant MAX_UINT64 = uint64(-1);
            
                string private constant ERROR_NUMBER_TOO_BIG = "UINT64_NUMBER_TOO_BIG";
            
                function toUint64(uint256 a) internal pure returns (uint64) {
                    require(a <= MAX_UINT64, ERROR_NUMBER_TOO_BIG);
                    return uint64(a);
                }
            }
            
            // File: contracts/common/TimeHelpers.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            contract TimeHelpers {
                using Uint256Helpers for uint256;
            
                /**
                * @dev Returns the current block number.
                *      Using a function rather than `block.number` allows us to easily mock the block number in
                *      tests.
                */
                function getBlockNumber() internal view returns (uint256) {
                    return block.number;
                }
            
                /**
                * @dev Returns the current block number, converted to uint64.
                *      Using a function rather than `block.number` allows us to easily mock the block number in
                *      tests.
                */
                function getBlockNumber64() internal view returns (uint64) {
                    return getBlockNumber().toUint64();
                }
            
                /**
                * @dev Returns the current timestamp.
                *      Using a function rather than `block.timestamp` allows us to easily mock it in
                *      tests.
                */
                function getTimestamp() internal view returns (uint256) {
                    return block.timestamp; // solium-disable-line security/no-block-members
                }
            
                /**
                * @dev Returns the current timestamp, converted to uint64.
                *      Using a function rather than `block.timestamp` allows us to easily mock it in
                *      tests.
                */
                function getTimestamp64() internal view returns (uint64) {
                    return getTimestamp().toUint64();
                }
            }
            
            // File: contracts/common/UnstructuredStorage.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            library UnstructuredStorage {
                function getStorageBool(bytes32 position) internal view returns (bool data) {
                    assembly { data := sload(position) }
                }
            
                function getStorageAddress(bytes32 position) internal view returns (address data) {
                    assembly { data := sload(position) }
                }
            
                function getStorageBytes32(bytes32 position) internal view returns (bytes32 data) {
                    assembly { data := sload(position) }
                }
            
                function getStorageUint256(bytes32 position) internal view returns (uint256 data) {
                    assembly { data := sload(position) }
                }
            
                function setStorageBool(bytes32 position, bool data) internal {
                    assembly { sstore(position, data) }
                }
            
                function setStorageAddress(bytes32 position, address data) internal {
                    assembly { sstore(position, data) }
                }
            
                function setStorageBytes32(bytes32 position, bytes32 data) internal {
                    assembly { sstore(position, data) }
                }
            
                function setStorageUint256(bytes32 position, uint256 data) internal {
                    assembly { sstore(position, data) }
                }
            }
            
            // File: contracts/common/Initializable.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            
            contract Initializable is TimeHelpers {
                using UnstructuredStorage for bytes32;
            
                // keccak256("aragonOS.initializable.initializationBlock")
                bytes32 internal constant INITIALIZATION_BLOCK_POSITION = 0xebb05b386a8d34882b8711d156f463690983dc47815980fb82aeeff1aa43579e;
            
                string private constant ERROR_ALREADY_INITIALIZED = "INIT_ALREADY_INITIALIZED";
                string private constant ERROR_NOT_INITIALIZED = "INIT_NOT_INITIALIZED";
            
                modifier onlyInit {
                    require(getInitializationBlock() == 0, ERROR_ALREADY_INITIALIZED);
                    _;
                }
            
                modifier isInitialized {
                    require(hasInitialized(), ERROR_NOT_INITIALIZED);
                    _;
                }
            
                /**
                * @return Block number in which the contract was initialized
                */
                function getInitializationBlock() public view returns (uint256) {
                    return INITIALIZATION_BLOCK_POSITION.getStorageUint256();
                }
            
                /**
                * @return Whether the contract has been initialized by the time of the current block
                */
                function hasInitialized() public view returns (bool) {
                    uint256 initializationBlock = getInitializationBlock();
                    return initializationBlock != 0 && getBlockNumber() >= initializationBlock;
                }
            
                /**
                * @dev Function to be called by top level contract after initialization has finished.
                */
                function initialized() internal onlyInit {
                    INITIALIZATION_BLOCK_POSITION.setStorageUint256(getBlockNumber());
                }
            
                /**
                * @dev Function to be called by top level contract after initialization to enable the contract
                *      at a future block number rather than immediately.
                */
                function initializedAt(uint256 _blockNumber) internal onlyInit {
                    INITIALIZATION_BLOCK_POSITION.setStorageUint256(_blockNumber);
                }
            }
            
            // File: contracts/common/Petrifiable.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            contract Petrifiable is Initializable {
                // Use block UINT256_MAX (which should be never) as the initializable date
                uint256 internal constant PETRIFIED_BLOCK = uint256(-1);
            
                function isPetrified() public view returns (bool) {
                    return getInitializationBlock() == PETRIFIED_BLOCK;
                }
            
                /**
                * @dev Function to be called by top level contract to prevent being initialized.
                *      Useful for freezing base contracts when they're used behind proxies.
                */
                function petrify() internal onlyInit {
                    initializedAt(PETRIFIED_BLOCK);
                }
            }
            
            // File: contracts/lib/token/ERC20.sol
            
            // See https://github.com/OpenZeppelin/openzeppelin-solidity/blob/a9f910d34f0ab33a1ae5e714f69f9596a02b4d91/contracts/token/ERC20/ERC20.sol
            
            pragma solidity ^0.4.24;
            
            
            /**
             * @title ERC20 interface
             * @dev see https://github.com/ethereum/EIPs/issues/20
             */
            contract ERC20 {
                function totalSupply() public view returns (uint256);
            
                function balanceOf(address _who) public view returns (uint256);
            
                function allowance(address _owner, address _spender)
                    public view returns (uint256);
            
                function transfer(address _to, uint256 _value) public returns (bool);
            
                function approve(address _spender, uint256 _value)
                    public returns (bool);
            
                function transferFrom(address _from, address _to, uint256 _value)
                    public returns (bool);
            
                event Transfer(
                    address indexed from,
                    address indexed to,
                    uint256 value
                );
            
                event Approval(
                    address indexed owner,
                    address indexed spender,
                    uint256 value
                );
            }
            
            // File: contracts/common/EtherTokenConstant.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            // aragonOS and aragon-apps rely on address(0) to denote native ETH, in
            // contracts where both tokens and ETH are accepted
            contract EtherTokenConstant {
                address internal constant ETH = address(0);
            }
            
            // File: contracts/common/SafeERC20.sol
            
            // Inspired by AdEx (https://github.com/AdExNetwork/adex-protocol-eth/blob/b9df617829661a7518ee10f4cb6c4108659dd6d5/contracts/libs/SafeERC20.sol)
            // and 0x (https://github.com/0xProject/0x-monorepo/blob/737d1dc54d72872e24abce5a1dbe1b66d35fa21a/contracts/protocol/contracts/protocol/AssetProxy/ERC20Proxy.sol#L143)
            
            pragma solidity ^0.4.24;
            
            
            
            library SafeERC20 {
                // Before 0.5, solidity has a mismatch between `address.transfer()` and `token.transfer()`:
                // https://github.com/ethereum/solidity/issues/3544
                bytes4 private constant TRANSFER_SELECTOR = 0xa9059cbb;
            
                string private constant ERROR_TOKEN_BALANCE_REVERTED = "SAFE_ERC_20_BALANCE_REVERTED";
                string private constant ERROR_TOKEN_ALLOWANCE_REVERTED = "SAFE_ERC_20_ALLOWANCE_REVERTED";
            
                function invokeAndCheckSuccess(address _addr, bytes memory _calldata)
                    private
                    returns (bool)
                {
                    bool ret;
                    assembly {
                        let ptr := mload(0x40)    // free memory pointer
            
                        let success := call(
                            gas,                  // forward all gas
                            _addr,                // address
                            0,                    // no value
                            add(_calldata, 0x20), // calldata start
                            mload(_calldata),     // calldata length
                            ptr,                  // write output over free memory
                            0x20                  // uint256 return
                        )
            
                        if gt(success, 0) {
                            // Check number of bytes returned from last function call
                            switch returndatasize
            
                            // No bytes returned: assume success
                            case 0 {
                                ret := 1
                            }
            
                            // 32 bytes returned: check if non-zero
                            case 0x20 {
                                // Only return success if returned data was true
                                // Already have output in ptr
                                ret := eq(mload(ptr), 1)
                            }
            
                            // Not sure what was returned: don't mark as success
                            default { }
                        }
                    }
                    return ret;
                }
            
                function staticInvoke(address _addr, bytes memory _calldata)
                    private
                    view
                    returns (bool, uint256)
                {
                    bool success;
                    uint256 ret;
                    assembly {
                        let ptr := mload(0x40)    // free memory pointer
            
                        success := staticcall(
                            gas,                  // forward all gas
                            _addr,                // address
                            add(_calldata, 0x20), // calldata start
                            mload(_calldata),     // calldata length
                            ptr,                  // write output over free memory
                            0x20                  // uint256 return
                        )
            
                        if gt(success, 0) {
                            ret := mload(ptr)
                        }
                    }
                    return (success, ret);
                }
            
                /**
                * @dev Same as a standards-compliant ERC20.transfer() that never reverts (returns false).
                *      Note that this makes an external call to the token.
                */
                function safeTransfer(ERC20 _token, address _to, uint256 _amount) internal returns (bool) {
                    bytes memory transferCallData = abi.encodeWithSelector(
                        TRANSFER_SELECTOR,
                        _to,
                        _amount
                    );
                    return invokeAndCheckSuccess(_token, transferCallData);
                }
            
                /**
                * @dev Same as a standards-compliant ERC20.transferFrom() that never reverts (returns false).
                *      Note that this makes an external call to the token.
                */
                function safeTransferFrom(ERC20 _token, address _from, address _to, uint256 _amount) internal returns (bool) {
                    bytes memory transferFromCallData = abi.encodeWithSelector(
                        _token.transferFrom.selector,
                        _from,
                        _to,
                        _amount
                    );
                    return invokeAndCheckSuccess(_token, transferFromCallData);
                }
            
                /**
                * @dev Same as a standards-compliant ERC20.approve() that never reverts (returns false).
                *      Note that this makes an external call to the token.
                */
                function safeApprove(ERC20 _token, address _spender, uint256 _amount) internal returns (bool) {
                    bytes memory approveCallData = abi.encodeWithSelector(
                        _token.approve.selector,
                        _spender,
                        _amount
                    );
                    return invokeAndCheckSuccess(_token, approveCallData);
                }
            
                /**
                * @dev Static call into ERC20.balanceOf().
                * Reverts if the call fails for some reason (should never fail).
                */
                function staticBalanceOf(ERC20 _token, address _owner) internal view returns (uint256) {
                    bytes memory balanceOfCallData = abi.encodeWithSelector(
                        _token.balanceOf.selector,
                        _owner
                    );
            
                    (bool success, uint256 tokenBalance) = staticInvoke(_token, balanceOfCallData);
                    require(success, ERROR_TOKEN_BALANCE_REVERTED);
            
                    return tokenBalance;
                }
            
                /**
                * @dev Static call into ERC20.allowance().
                * Reverts if the call fails for some reason (should never fail).
                */
                function staticAllowance(ERC20 _token, address _owner, address _spender) internal view returns (uint256) {
                    bytes memory allowanceCallData = abi.encodeWithSelector(
                        _token.allowance.selector,
                        _owner,
                        _spender
                    );
            
                    (bool success, uint256 allowance) = staticInvoke(_token, allowanceCallData);
                    require(success, ERROR_TOKEN_ALLOWANCE_REVERTED);
            
                    return allowance;
                }
            
                /**
                * @dev Static call into ERC20.totalSupply().
                * Reverts if the call fails for some reason (should never fail).
                */
                function staticTotalSupply(ERC20 _token) internal view returns (uint256) {
                    bytes memory totalSupplyCallData = abi.encodeWithSelector(_token.totalSupply.selector);
            
                    (bool success, uint256 totalSupply) = staticInvoke(_token, totalSupplyCallData);
                    require(success, ERROR_TOKEN_ALLOWANCE_REVERTED);
            
                    return totalSupply;
                }
            }
            
            // File: contracts/common/VaultRecoverable.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            
            
            
            
            contract VaultRecoverable is IVaultRecoverable, EtherTokenConstant, IsContract {
                using SafeERC20 for ERC20;
            
                string private constant ERROR_DISALLOWED = "RECOVER_DISALLOWED";
                string private constant ERROR_VAULT_NOT_CONTRACT = "RECOVER_VAULT_NOT_CONTRACT";
                string private constant ERROR_TOKEN_TRANSFER_FAILED = "RECOVER_TOKEN_TRANSFER_FAILED";
            
                /**
                 * @notice Send funds to recovery Vault. This contract should never receive funds,
                 *         but in case it does, this function allows one to recover them.
                 * @param _token Token balance to be sent to recovery vault.
                 */
                function transferToVault(address _token) external {
                    require(allowRecoverability(_token), ERROR_DISALLOWED);
                    address vault = getRecoveryVault();
                    require(isContract(vault), ERROR_VAULT_NOT_CONTRACT);
            
                    uint256 balance;
                    if (_token == ETH) {
                        balance = address(this).balance;
                        vault.transfer(balance);
                    } else {
                        ERC20 token = ERC20(_token);
                        balance = token.staticBalanceOf(this);
                        require(token.safeTransfer(vault, balance), ERROR_TOKEN_TRANSFER_FAILED);
                    }
            
                    emit RecoverToVault(vault, _token, balance);
                }
            
                /**
                * @dev By default deriving from AragonApp makes it recoverable
                * @param token Token address that would be recovered
                * @return bool whether the app allows the recovery
                */
                function allowRecoverability(address token) public view returns (bool) {
                    return true;
                }
            
                // Cast non-implemented interface to be public so we can use it internally
                function getRecoveryVault() public view returns (address);
            }
            
            // File: contracts/apps/AppStorage.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            
            
            contract AppStorage {
                using UnstructuredStorage for bytes32;
            
                /* Hardcoded constants to save gas
                bytes32 internal constant KERNEL_POSITION = keccak256("aragonOS.appStorage.kernel");
                bytes32 internal constant APP_ID_POSITION = keccak256("aragonOS.appStorage.appId");
                */
                bytes32 internal constant KERNEL_POSITION = 0x4172f0f7d2289153072b0a6ca36959e0cbe2efc3afe50fc81636caa96338137b;
                bytes32 internal constant APP_ID_POSITION = 0xd625496217aa6a3453eecb9c3489dc5a53e6c67b444329ea2b2cbc9ff547639b;
            
                function kernel() public view returns (IKernel) {
                    return IKernel(KERNEL_POSITION.getStorageAddress());
                }
            
                function appId() public view returns (bytes32) {
                    return APP_ID_POSITION.getStorageBytes32();
                }
            
                function setKernel(IKernel _kernel) internal {
                    KERNEL_POSITION.setStorageAddress(address(_kernel));
                }
            
                function setAppId(bytes32 _appId) internal {
                    APP_ID_POSITION.setStorageBytes32(_appId);
                }
            }
            
            // File: contracts/lib/misc/ERCProxy.sol
            
            /*
             * SPDX-License-Identitifer:    MIT
             */
            
            pragma solidity ^0.4.24;
            
            
            contract ERCProxy {
                uint256 internal constant FORWARDING = 1;
                uint256 internal constant UPGRADEABLE = 2;
            
                function proxyType() public pure returns (uint256 proxyTypeId);
                function implementation() public view returns (address codeAddr);
            }
            
            // File: contracts/common/DelegateProxy.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            contract DelegateProxy is ERCProxy, IsContract {
                uint256 internal constant FWD_GAS_LIMIT = 10000;
            
                /**
                * @dev Performs a delegatecall and returns whatever the delegatecall returned (entire context execution will return!)
                * @param _dst Destination address to perform the delegatecall
                * @param _calldata Calldata for the delegatecall
                */
                function delegatedFwd(address _dst, bytes _calldata) internal {
                    require(isContract(_dst));
                    uint256 fwdGasLimit = FWD_GAS_LIMIT;
            
                    assembly {
                        let result := delegatecall(sub(gas, fwdGasLimit), _dst, add(_calldata, 0x20), mload(_calldata), 0, 0)
                        let size := returndatasize
                        let ptr := mload(0x40)
                        returndatacopy(ptr, 0, size)
            
                        // revert instead of invalid() bc if the underlying call failed with invalid() it already wasted gas.
                        // if the call returned error data, forward it
                        switch result case 0 { revert(ptr, size) }
                        default { return(ptr, size) }
                    }
                }
            }
            
            // File: contracts/common/DepositableStorage.sol
            
            pragma solidity 0.4.24;
            
            
            
            contract DepositableStorage {
                using UnstructuredStorage for bytes32;
            
                // keccak256("aragonOS.depositableStorage.depositable")
                bytes32 internal constant DEPOSITABLE_POSITION = 0x665fd576fbbe6f247aff98f5c94a561e3f71ec2d3c988d56f12d342396c50cea;
            
                function isDepositable() public view returns (bool) {
                    return DEPOSITABLE_POSITION.getStorageBool();
                }
            
                function setDepositable(bool _depositable) internal {
                    DEPOSITABLE_POSITION.setStorageBool(_depositable);
                }
            }
            
            // File: contracts/common/DepositableDelegateProxy.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            contract DepositableDelegateProxy is DepositableStorage, DelegateProxy {
                event ProxyDeposit(address sender, uint256 value);
            
                function () external payable {
                    uint256 forwardGasThreshold = FWD_GAS_LIMIT;
                    bytes32 isDepositablePosition = DEPOSITABLE_POSITION;
            
                    // Optimized assembly implementation to prevent EIP-1884 from breaking deposits, reference code in Solidity:
                    // https://github.com/aragon/aragonOS/blob/v4.2.1/contracts/common/DepositableDelegateProxy.sol#L10-L20
                    assembly {
                        // Continue only if the gas left is lower than the threshold for forwarding to the implementation code,
                        // otherwise continue outside of the assembly block.
                        if lt(gas, forwardGasThreshold) {
                            // Only accept the deposit and emit an event if all of the following are true:
                            // the proxy accepts deposits (isDepositable), msg.data.length == 0, and msg.value > 0
                            if and(and(sload(isDepositablePosition), iszero(calldatasize)), gt(callvalue, 0)) {
                                // Equivalent Solidity code for emitting the event:
                                // emit ProxyDeposit(msg.sender, msg.value);
            
                                let logData := mload(0x40) // free memory pointer
                                mstore(logData, caller) // add 'msg.sender' to the log data (first event param)
                                mstore(add(logData, 0x20), callvalue) // add 'msg.value' to the log data (second event param)
            
                                // Emit an event with one topic to identify the event: keccak256('ProxyDeposit(address,uint256)') = 0x15ee...dee1
                                log1(logData, 0x40, 0x15eeaa57c7bd188c1388020bcadc2c436ec60d647d36ef5b9eb3c742217ddee1)
            
                                stop() // Stop. Exits execution context
                            }
            
                            // If any of above checks failed, revert the execution (if ETH was sent, it is returned to the sender)
                            revert(0, 0)
                        }
                    }
            
                    address target = implementation();
                    delegatedFwd(target, msg.data);
                }
            }
            
            // File: contracts/apps/AppProxyBase.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            
            
            contract AppProxyBase is AppStorage, DepositableDelegateProxy, KernelNamespaceConstants {
                /**
                * @dev Initialize AppProxy
                * @param _kernel Reference to organization kernel for the app
                * @param _appId Identifier for app
                * @param _initializePayload Payload for call to be made after setup to initialize
                */
                constructor(IKernel _kernel, bytes32 _appId, bytes _initializePayload) public {
                    setKernel(_kernel);
                    setAppId(_appId);
            
                    // Implicit check that kernel is actually a Kernel
                    // The EVM doesn't actually provide a way for us to make sure, but we can force a revert to
                    // occur if the kernel is set to 0x0 or a non-code address when we try to call a method on
                    // it.
                    address appCode = getAppBase(_appId);
            
                    // If initialize payload is provided, it will be executed
                    if (_initializePayload.length > 0) {
                        require(isContract(appCode));
                        // Cannot make delegatecall as a delegateproxy.delegatedFwd as it
                        // returns ending execution context and halts contract deployment
                        require(appCode.delegatecall(_initializePayload));
                    }
                }
            
                function getAppBase(bytes32 _appId) internal view returns (address) {
                    return kernel().getApp(KERNEL_APP_BASES_NAMESPACE, _appId);
                }
            }
            
            // File: contracts/apps/AppProxyUpgradeable.sol
            
            pragma solidity 0.4.24;
            
            
            
            contract AppProxyUpgradeable is AppProxyBase {
                /**
                * @dev Initialize AppProxyUpgradeable (makes it an upgradeable Aragon app)
                * @param _kernel Reference to organization kernel for the app
                * @param _appId Identifier for app
                * @param _initializePayload Payload for call to be made after setup to initialize
                */
                constructor(IKernel _kernel, bytes32 _appId, bytes _initializePayload)
                    AppProxyBase(_kernel, _appId, _initializePayload)
                    public // solium-disable-line visibility-first
                {
                    // solium-disable-previous-line no-empty-blocks
                }
            
                /**
                 * @dev ERC897, the address the proxy would delegate calls to
                 */
                function implementation() public view returns (address) {
                    return getAppBase(appId());
                }
            
                /**
                 * @dev ERC897, whether it is a forwarding (1) or an upgradeable (2) proxy
                 */
                function proxyType() public pure returns (uint256 proxyTypeId) {
                    return UPGRADEABLE;
                }
            }
            
            // File: contracts/apps/AppProxyPinned.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            
            contract AppProxyPinned is IsContract, AppProxyBase {
                using UnstructuredStorage for bytes32;
            
                // keccak256("aragonOS.appStorage.pinnedCode")
                bytes32 internal constant PINNED_CODE_POSITION = 0xdee64df20d65e53d7f51cb6ab6d921a0a6a638a91e942e1d8d02df28e31c038e;
            
                /**
                * @dev Initialize AppProxyPinned (makes it an un-upgradeable Aragon app)
                * @param _kernel Reference to organization kernel for the app
                * @param _appId Identifier for app
                * @param _initializePayload Payload for call to be made after setup to initialize
                */
                constructor(IKernel _kernel, bytes32 _appId, bytes _initializePayload)
                    AppProxyBase(_kernel, _appId, _initializePayload)
                    public // solium-disable-line visibility-first
                {
                    setPinnedCode(getAppBase(_appId));
                    require(isContract(pinnedCode()));
                }
            
                /**
                 * @dev ERC897, the address the proxy would delegate calls to
                 */
                function implementation() public view returns (address) {
                    return pinnedCode();
                }
            
                /**
                 * @dev ERC897, whether it is a forwarding (1) or an upgradeable (2) proxy
                 */
                function proxyType() public pure returns (uint256 proxyTypeId) {
                    return FORWARDING;
                }
            
                function setPinnedCode(address _pinnedCode) internal {
                    PINNED_CODE_POSITION.setStorageAddress(_pinnedCode);
                }
            
                function pinnedCode() internal view returns (address) {
                    return PINNED_CODE_POSITION.getStorageAddress();
                }
            }
            
            // File: contracts/factory/AppProxyFactory.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            contract AppProxyFactory {
                event NewAppProxy(address proxy, bool isUpgradeable, bytes32 appId);
            
                /**
                * @notice Create a new upgradeable app instance on `_kernel` with identifier `_appId`
                * @param _kernel App's Kernel reference
                * @param _appId Identifier for app
                * @return AppProxyUpgradeable
                */
                function newAppProxy(IKernel _kernel, bytes32 _appId) public returns (AppProxyUpgradeable) {
                    return newAppProxy(_kernel, _appId, new bytes(0));
                }
            
                /**
                * @notice Create a new upgradeable app instance on `_kernel` with identifier `_appId` and initialization payload `_initializePayload`
                * @param _kernel App's Kernel reference
                * @param _appId Identifier for app
                * @return AppProxyUpgradeable
                */
                function newAppProxy(IKernel _kernel, bytes32 _appId, bytes _initializePayload) public returns (AppProxyUpgradeable) {
                    AppProxyUpgradeable proxy = new AppProxyUpgradeable(_kernel, _appId, _initializePayload);
                    emit NewAppProxy(address(proxy), true, _appId);
                    return proxy;
                }
            
                /**
                * @notice Create a new pinned app instance on `_kernel` with identifier `_appId`
                * @param _kernel App's Kernel reference
                * @param _appId Identifier for app
                * @return AppProxyPinned
                */
                function newAppProxyPinned(IKernel _kernel, bytes32 _appId) public returns (AppProxyPinned) {
                    return newAppProxyPinned(_kernel, _appId, new bytes(0));
                }
            
                /**
                * @notice Create a new pinned app instance on `_kernel` with identifier `_appId` and initialization payload `_initializePayload`
                * @param _kernel App's Kernel reference
                * @param _appId Identifier for app
                * @param _initializePayload Proxy initialization payload
                * @return AppProxyPinned
                */
                function newAppProxyPinned(IKernel _kernel, bytes32 _appId, bytes _initializePayload) public returns (AppProxyPinned) {
                    AppProxyPinned proxy = new AppProxyPinned(_kernel, _appId, _initializePayload);
                    emit NewAppProxy(address(proxy), false, _appId);
                    return proxy;
                }
            }
            
            // File: contracts/kernel/Kernel.sol
            
            pragma solidity 0.4.24;
            
            
            
            
            
            
            
            
            
            
            
            
            
            // solium-disable-next-line max-len
            contract Kernel is IKernel, KernelStorage, KernelAppIds, KernelNamespaceConstants, Petrifiable, IsContract, VaultRecoverable, AppProxyFactory, ACLSyntaxSugar {
                /* Hardcoded constants to save gas
                bytes32 public constant APP_MANAGER_ROLE = keccak256("APP_MANAGER_ROLE");
                */
                bytes32 public constant APP_MANAGER_ROLE = 0xb6d92708f3d4817afc106147d969e229ced5c46e65e0a5002a0d391287762bd0;
            
                string private constant ERROR_APP_NOT_CONTRACT = "KERNEL_APP_NOT_CONTRACT";
                string private constant ERROR_INVALID_APP_CHANGE = "KERNEL_INVALID_APP_CHANGE";
                string private constant ERROR_AUTH_FAILED = "KERNEL_AUTH_FAILED";
            
                /**
                * @dev Constructor that allows the deployer to choose if the base instance should be petrified immediately.
                * @param _shouldPetrify Immediately petrify this instance so that it can never be initialized
                */
                constructor(bool _shouldPetrify) public {
                    if (_shouldPetrify) {
                        petrify();
                    }
                }
            
                /**
                * @dev Initialize can only be called once. It saves the block number in which it was initialized.
                * @notice Initialize this kernel instance along with its ACL and set `_permissionsCreator` as the entity that can create other permissions
                * @param _baseAcl Address of base ACL app
                * @param _permissionsCreator Entity that will be given permission over createPermission
                */
                function initialize(IACL _baseAcl, address _permissionsCreator) public onlyInit {
                    initialized();
            
                    // Set ACL base
                    _setApp(KERNEL_APP_BASES_NAMESPACE, KERNEL_DEFAULT_ACL_APP_ID, _baseAcl);
            
                    // Create ACL instance and attach it as the default ACL app
                    IACL acl = IACL(newAppProxy(this, KERNEL_DEFAULT_ACL_APP_ID));
                    acl.initialize(_permissionsCreator);
                    _setApp(KERNEL_APP_ADDR_NAMESPACE, KERNEL_DEFAULT_ACL_APP_ID, acl);
            
                    recoveryVaultAppId = KERNEL_DEFAULT_VAULT_APP_ID;
                }
            
                /**
                * @dev Create a new instance of an app linked to this kernel
                * @notice Create a new upgradeable instance of `_appId` app linked to the Kernel, setting its code to `_appBase`
                * @param _appId Identifier for app
                * @param _appBase Address of the app's base implementation
                * @return AppProxy instance
                */
                function newAppInstance(bytes32 _appId, address _appBase)
                    public
                    auth(APP_MANAGER_ROLE, arr(KERNEL_APP_BASES_NAMESPACE, _appId))
                    returns (ERCProxy appProxy)
                {
                    return newAppInstance(_appId, _appBase, new bytes(0), false);
                }
            
                /**
                * @dev Create a new instance of an app linked to this kernel and set its base
                *      implementation if it was not already set
                * @notice Create a new upgradeable instance of `_appId` app linked to the Kernel, setting its code to `_appBase`. `_setDefault ? 'Also sets it as the default app instance.':''`
                * @param _appId Identifier for app
                * @param _appBase Address of the app's base implementation
                * @param _initializePayload Payload for call made by the proxy during its construction to initialize
                * @param _setDefault Whether the app proxy app is the default one.
                *        Useful when the Kernel needs to know of an instance of a particular app,
                *        like Vault for escape hatch mechanism.
                * @return AppProxy instance
                */
                function newAppInstance(bytes32 _appId, address _appBase, bytes _initializePayload, bool _setDefault)
                    public
                    auth(APP_MANAGER_ROLE, arr(KERNEL_APP_BASES_NAMESPACE, _appId))
                    returns (ERCProxy appProxy)
                {
                    _setAppIfNew(KERNEL_APP_BASES_NAMESPACE, _appId, _appBase);
                    appProxy = newAppProxy(this, _appId, _initializePayload);
                    // By calling setApp directly and not the internal functions, we make sure the params are checked
                    // and it will only succeed if sender has permissions to set something to the namespace.
                    if (_setDefault) {
                        setApp(KERNEL_APP_ADDR_NAMESPACE, _appId, appProxy);
                    }
                }
            
                /**
                * @dev Create a new pinned instance of an app linked to this kernel
                * @notice Create a new non-upgradeable instance of `_appId` app linked to the Kernel, setting its code to `_appBase`.
                * @param _appId Identifier for app
                * @param _appBase Address of the app's base implementation
                * @return AppProxy instance
                */
                function newPinnedAppInstance(bytes32 _appId, address _appBase)
                    public
                    auth(APP_MANAGER_ROLE, arr(KERNEL_APP_BASES_NAMESPACE, _appId))
                    returns (ERCProxy appProxy)
                {
                    return newPinnedAppInstance(_appId, _appBase, new bytes(0), false);
                }
            
                /**
                * @dev Create a new pinned instance of an app linked to this kernel and set
                *      its base implementation if it was not already set
                * @notice Create a new non-upgradeable instance of `_appId` app linked to the Kernel, setting its code to `_appBase`. `_setDefault ? 'Also sets it as the default app instance.':''`
                * @param _appId Identifier for app
                * @param _appBase Address of the app's base implementation
                * @param _initializePayload Payload for call made by the proxy during its construction to initialize
                * @param _setDefault Whether the app proxy app is the default one.
                *        Useful when the Kernel needs to know of an instance of a particular app,
                *        like Vault for escape hatch mechanism.
                * @return AppProxy instance
                */
                function newPinnedAppInstance(bytes32 _appId, address _appBase, bytes _initializePayload, bool _setDefault)
                    public
                    auth(APP_MANAGER_ROLE, arr(KERNEL_APP_BASES_NAMESPACE, _appId))
                    returns (ERCProxy appProxy)
                {
                    _setAppIfNew(KERNEL_APP_BASES_NAMESPACE, _appId, _appBase);
                    appProxy = newAppProxyPinned(this, _appId, _initializePayload);
                    // By calling setApp directly and not the internal functions, we make sure the params are checked
                    // and it will only succeed if sender has permissions to set something to the namespace.
                    if (_setDefault) {
                        setApp(KERNEL_APP_ADDR_NAMESPACE, _appId, appProxy);
                    }
                }
            
                /**
                * @dev Set the resolving address of an app instance or base implementation
                * @notice Set the resolving address of `_appId` in namespace `_namespace` to `_app`
                * @param _namespace App namespace to use
                * @param _appId Identifier for app
                * @param _app Address of the app instance or base implementation
                * @return ID of app
                */
                function setApp(bytes32 _namespace, bytes32 _appId, address _app)
                    public
                    auth(APP_MANAGER_ROLE, arr(_namespace, _appId))
                {
                    _setApp(_namespace, _appId, _app);
                }
            
                /**
                * @dev Set the default vault id for the escape hatch mechanism
                * @param _recoveryVaultAppId Identifier of the recovery vault app
                */
                function setRecoveryVaultAppId(bytes32 _recoveryVaultAppId)
                    public
                    auth(APP_MANAGER_ROLE, arr(KERNEL_APP_ADDR_NAMESPACE, _recoveryVaultAppId))
                {
                    recoveryVaultAppId = _recoveryVaultAppId;
                }
            
                // External access to default app id and namespace constants to mimic default getters for constants
                /* solium-disable function-order, mixedcase */
                function CORE_NAMESPACE() external pure returns (bytes32) { return KERNEL_CORE_NAMESPACE; }
                function APP_BASES_NAMESPACE() external pure returns (bytes32) { return KERNEL_APP_BASES_NAMESPACE; }
                function APP_ADDR_NAMESPACE() external pure returns (bytes32) { return KERNEL_APP_ADDR_NAMESPACE; }
                function KERNEL_APP_ID() external pure returns (bytes32) { return KERNEL_CORE_APP_ID; }
                function DEFAULT_ACL_APP_ID() external pure returns (bytes32) { return KERNEL_DEFAULT_ACL_APP_ID; }
                /* solium-enable function-order, mixedcase */
            
                /**
                * @dev Get the address of an app instance or base implementation
                * @param _namespace App namespace to use
                * @param _appId Identifier for app
                * @return Address of the app
                */
                function getApp(bytes32 _namespace, bytes32 _appId) public view returns (address) {
                    return apps[_namespace][_appId];
                }
            
                /**
                * @dev Get the address of the recovery Vault instance (to recover funds)
                * @return Address of the Vault
                */
                function getRecoveryVault() public view returns (address) {
                    return apps[KERNEL_APP_ADDR_NAMESPACE][recoveryVaultAppId];
                }
            
                /**
                * @dev Get the installed ACL app
                * @return ACL app
                */
                function acl() public view returns (IACL) {
                    return IACL(getApp(KERNEL_APP_ADDR_NAMESPACE, KERNEL_DEFAULT_ACL_APP_ID));
                }
            
                /**
                * @dev Function called by apps to check ACL on kernel or to check permission status
                * @param _who Sender of the original call
                * @param _where Address of the app
                * @param _what Identifier for a group of actions in app
                * @param _how Extra data for ACL auth
                * @return Boolean indicating whether the ACL allows the role or not.
                *         Always returns false if the kernel hasn't been initialized yet.
                */
                function hasPermission(address _who, address _where, bytes32 _what, bytes _how) public view returns (bool) {
                    IACL defaultAcl = acl();
                    return address(defaultAcl) != address(0) && // Poor man's initialization check (saves gas)
                        defaultAcl.hasPermission(_who, _where, _what, _how);
                }
            
                function _setApp(bytes32 _namespace, bytes32 _appId, address _app) internal {
                    require(isContract(_app), ERROR_APP_NOT_CONTRACT);
                    apps[_namespace][_appId] = _app;
                    emit SetApp(_namespace, _appId, _app);
                }
            
                function _setAppIfNew(bytes32 _namespace, bytes32 _appId, address _app) internal {
                    address app = getApp(_namespace, _appId);
                    if (app != address(0)) {
                        // The only way to set an app is if it passes the isContract check, so no need to check it again
                        require(app == _app, ERROR_INVALID_APP_CHANGE);
                    } else {
                        _setApp(_namespace, _appId, _app);
                    }
                }
            
                modifier auth(bytes32 _role, uint256[] memory _params) {
                    require(
                        hasPermission(msg.sender, address(this), _role, ConversionHelpers.dangerouslyCastUintArrayToBytes(_params)),
                        ERROR_AUTH_FAILED
                    );
                    _;
                }
            }

            File 5 of 5: Lido
            // SPDX-FileCopyrightText: 2020 Lido <[email protected]>
            // SPDX-License-Identifier: GPL-3.0
            /* See contracts/COMPILERS.md */
            pragma solidity 0.4.24;
            import "@aragon/os/contracts/apps/AragonApp.sol";
            import "@aragon/os/contracts/lib/math/SafeMath.sol";
            import "@aragon/os/contracts/lib/math/SafeMath64.sol";
            import "solidity-bytes-utils/contracts/BytesLib.sol";
            import "./interfaces/ILido.sol";
            import "./interfaces/INodeOperatorsRegistry.sol";
            import "./interfaces/IDepositContract.sol";
            import "./interfaces/ILidoExecutionLayerRewardsVault.sol";
            import "./StETH.sol";
            import "./lib/StakeLimitUtils.sol";
            interface IERC721 {
                /// @notice Transfer ownership of an NFT
                /// @param _from The current owner of the NFT
                /// @param _to The new owner
                /// @param _tokenId The NFT to transfer
                function transferFrom(address _from, address _to, uint256 _tokenId) external payable;
            }
            /**
            * @title Liquid staking pool implementation
            *
            * Lido is an Ethereum 2.0 liquid staking protocol solving the problem of frozen staked Ethers
            * until transfers become available in Ethereum 2.0.
            * Whitepaper: https://lido.fi/static/Lido:Ethereum-Liquid-Staking.pdf
            *
            * NOTE: the code below assumes moderate amount of node operators, e.g. up to 200.
            *
            * Since balances of all token holders change when the amount of total pooled Ether
            * changes, this token cannot fully implement ERC20 standard: it only emits `Transfer`
            * events upon explicit transfer between holders. In contrast, when Lido oracle reports
            * rewards, no Transfer events are generated: doing so would require emitting an event
            * for each token holder and thus running an unbounded loop.
            *
            * At the moment withdrawals are not possible in the beacon chain and there's no workaround.
            * Pool will be upgraded to an actual implementation when withdrawals are enabled
            * (Phase 1.5 or 2 of Eth2 launch, likely late 2022 or 2023).
            */
            contract Lido is ILido, StETH, AragonApp {
                using SafeMath for uint256;
                using UnstructuredStorage for bytes32;
                using StakeLimitUnstructuredStorage for bytes32;
                using StakeLimitUtils for StakeLimitState.Data;
                /// ACL
                bytes32 constant public PAUSE_ROLE = keccak256("PAUSE_ROLE");
                bytes32 constant public RESUME_ROLE = keccak256("RESUME_ROLE");
                bytes32 constant public STAKING_PAUSE_ROLE = keccak256("STAKING_PAUSE_ROLE");
                bytes32 constant public STAKING_CONTROL_ROLE = keccak256("STAKING_CONTROL_ROLE");
                bytes32 constant public MANAGE_FEE = keccak256("MANAGE_FEE");
                bytes32 constant public MANAGE_WITHDRAWAL_KEY = keccak256("MANAGE_WITHDRAWAL_KEY");
                bytes32 constant public MANAGE_PROTOCOL_CONTRACTS_ROLE = keccak256("MANAGE_PROTOCOL_CONTRACTS_ROLE");
                bytes32 constant public BURN_ROLE = keccak256("BURN_ROLE");
                bytes32 constant public DEPOSIT_ROLE = keccak256("DEPOSIT_ROLE");
                bytes32 constant public SET_EL_REWARDS_VAULT_ROLE = keccak256("SET_EL_REWARDS_VAULT_ROLE");
                bytes32 constant public SET_EL_REWARDS_WITHDRAWAL_LIMIT_ROLE = keccak256(
                    "SET_EL_REWARDS_WITHDRAWAL_LIMIT_ROLE"
                );
                uint256 constant public PUBKEY_LENGTH = 48;
                uint256 constant public WITHDRAWAL_CREDENTIALS_LENGTH = 32;
                uint256 constant public SIGNATURE_LENGTH = 96;
                uint256 constant public DEPOSIT_SIZE = 32 ether;
                uint256 internal constant DEPOSIT_AMOUNT_UNIT = 1000000000 wei;
                uint256 internal constant TOTAL_BASIS_POINTS = 10000;
                /// @dev default value for maximum number of Ethereum 2.0 validators registered in a single depositBufferedEther call
                uint256 internal constant DEFAULT_MAX_DEPOSITS_PER_CALL = 150;
                bytes32 internal constant FEE_POSITION = keccak256("lido.Lido.fee");
                bytes32 internal constant TREASURY_FEE_POSITION = keccak256("lido.Lido.treasuryFee");
                bytes32 internal constant INSURANCE_FEE_POSITION = keccak256("lido.Lido.insuranceFee");
                bytes32 internal constant NODE_OPERATORS_FEE_POSITION = keccak256("lido.Lido.nodeOperatorsFee");
                bytes32 internal constant DEPOSIT_CONTRACT_POSITION = keccak256("lido.Lido.depositContract");
                bytes32 internal constant ORACLE_POSITION = keccak256("lido.Lido.oracle");
                bytes32 internal constant NODE_OPERATORS_REGISTRY_POSITION = keccak256("lido.Lido.nodeOperatorsRegistry");
                bytes32 internal constant TREASURY_POSITION = keccak256("lido.Lido.treasury");
                bytes32 internal constant INSURANCE_FUND_POSITION = keccak256("lido.Lido.insuranceFund");
                bytes32 internal constant EL_REWARDS_VAULT_POSITION = keccak256("lido.Lido.executionLayerRewardsVault");
                /// @dev storage slot position of the staking rate limit structure
                bytes32 internal constant STAKING_STATE_POSITION = keccak256("lido.Lido.stakeLimit");
                /// @dev amount of Ether (on the current Ethereum side) buffered on this smart contract balance
                bytes32 internal constant BUFFERED_ETHER_POSITION = keccak256("lido.Lido.bufferedEther");
                /// @dev number of deposited validators (incrementing counter of deposit operations).
                bytes32 internal constant DEPOSITED_VALIDATORS_POSITION = keccak256("lido.Lido.depositedValidators");
                /// @dev total amount of Beacon-side Ether (sum of all the balances of Lido validators)
                bytes32 internal constant BEACON_BALANCE_POSITION = keccak256("lido.Lido.beaconBalance");
                /// @dev number of Lido's validators available in the Beacon state
                bytes32 internal constant BEACON_VALIDATORS_POSITION = keccak256("lido.Lido.beaconValidators");
                /// @dev percent in basis points of total pooled ether allowed to withdraw from LidoExecutionLayerRewardsVault per LidoOracle report
                bytes32 internal constant EL_REWARDS_WITHDRAWAL_LIMIT_POSITION = keccak256("lido.Lido.ELRewardsWithdrawalLimit");
                /// @dev Just a counter of total amount of execution layer rewards received by Lido contract
                /// Not used in the logic
                bytes32 internal constant TOTAL_EL_REWARDS_COLLECTED_POSITION = keccak256("lido.Lido.totalELRewardsCollected");
                /// @dev Credentials which allows the DAO to withdraw Ether on the 2.0 side
                bytes32 internal constant WITHDRAWAL_CREDENTIALS_POSITION = keccak256("lido.Lido.withdrawalCredentials");
                /**
                * @dev As AragonApp, Lido contract must be initialized with following variables:
                * @param _depositContract official ETH2 Deposit contract
                * @param _oracle oracle contract
                * @param _operators instance of Node Operators Registry
                * @param _treasury treasury contract
                * @param _insuranceFund insurance fund contract
                * NB: by default, staking and the whole Lido pool are in paused state
                */
                function initialize(
                    IDepositContract _depositContract,
                    address _oracle,
                    INodeOperatorsRegistry _operators,
                    address _treasury,
                    address _insuranceFund
                )
                    public onlyInit
                {
                    NODE_OPERATORS_REGISTRY_POSITION.setStorageAddress(address(_operators));
                    DEPOSIT_CONTRACT_POSITION.setStorageAddress(address(_depositContract));
                    _setProtocolContracts(_oracle, _treasury, _insuranceFund);
                    initialized();
                }
                /**
                * @notice Stops accepting new Ether to the protocol
                *
                * @dev While accepting new Ether is stopped, calls to the `submit` function,
                * as well as to the default payable function, will revert.
                *
                * Emits `StakingPaused` event.
                */
                function pauseStaking() external {
                    _auth(STAKING_PAUSE_ROLE);
                    _pauseStaking();
                }
                /**
                * @notice Resumes accepting new Ether to the protocol (if `pauseStaking` was called previously)
                * NB: Staking could be rate-limited by imposing a limit on the stake amount
                * at each moment in time, see `setStakingLimit()` and `removeStakingLimit()`
                *
                * @dev Preserves staking limit if it was set previously
                *
                * Emits `StakingResumed` event
                */
                function resumeStaking() external {
                    _auth(STAKING_CONTROL_ROLE);
                    _resumeStaking();
                }
                /**
                * @notice Sets the staking rate limit
                *
                * ▲ Stake limit
                * │.....  .....   ........ ...            ....     ... Stake limit = max
                * │      .       .        .   .   .      .    . . .
                * │     .       .              . .  . . .      . .
                * │            .                .  . . .
                * │──────────────────────────────────────────────────> Time
                * │     ^      ^          ^   ^^^  ^ ^ ^     ^^^ ^     Stake events
                *
                * @dev Reverts if:
                * - `_maxStakeLimit` == 0
                * - `_maxStakeLimit` >= 2^96
                * - `_maxStakeLimit` < `_stakeLimitIncreasePerBlock`
                * - `_maxStakeLimit` / `_stakeLimitIncreasePerBlock` >= 2^32 (only if `_stakeLimitIncreasePerBlock` != 0)
                *
                * Emits `StakingLimitSet` event
                *
                * @param _maxStakeLimit max stake limit value
                * @param _stakeLimitIncreasePerBlock stake limit increase per single block
                */
                function setStakingLimit(uint256 _maxStakeLimit, uint256 _stakeLimitIncreasePerBlock) external {
                    _auth(STAKING_CONTROL_ROLE);
                    STAKING_STATE_POSITION.setStorageStakeLimitStruct(
                        STAKING_STATE_POSITION.getStorageStakeLimitStruct().setStakingLimit(
                            _maxStakeLimit,
                            _stakeLimitIncreasePerBlock
                        )
                    );
                    emit StakingLimitSet(_maxStakeLimit, _stakeLimitIncreasePerBlock);
                }
                /**
                * @notice Removes the staking rate limit
                *
                * Emits `StakingLimitRemoved` event
                */
                function removeStakingLimit() external {
                    _auth(STAKING_CONTROL_ROLE);
                    STAKING_STATE_POSITION.setStorageStakeLimitStruct(
                        STAKING_STATE_POSITION.getStorageStakeLimitStruct().removeStakingLimit()
                    );
                    emit StakingLimitRemoved();
                }
                /**
                * @notice Check staking state: whether it's paused or not
                */
                function isStakingPaused() external view returns (bool) {
                    return STAKING_STATE_POSITION.getStorageStakeLimitStruct().isStakingPaused();
                }
                /**
                * @notice Returns how much Ether can be staked in the current block
                * @dev Special return values:
                * - 2^256 - 1 if staking is unlimited;
                * - 0 if staking is paused or if limit is exhausted.
                */
                function getCurrentStakeLimit() public view returns (uint256) {
                    return _getCurrentStakeLimit(STAKING_STATE_POSITION.getStorageStakeLimitStruct());
                }
                /**
                * @notice Returns full info about current stake limit params and state
                * @dev Might be used for the advanced integration requests.
                * @return isStakingPaused staking pause state (equivalent to return of isStakingPaused())
                * @return isStakingLimitSet whether the stake limit is set
                * @return currentStakeLimit current stake limit (equivalent to return of getCurrentStakeLimit())
                * @return maxStakeLimit max stake limit
                * @return maxStakeLimitGrowthBlocks blocks needed to restore max stake limit from the fully exhausted state
                * @return prevStakeLimit previously reached stake limit
                * @return prevStakeBlockNumber previously seen block number
                */
                function getStakeLimitFullInfo() external view returns (
                    bool isStakingPaused,
                    bool isStakingLimitSet,
                    uint256 currentStakeLimit,
                    uint256 maxStakeLimit,
                    uint256 maxStakeLimitGrowthBlocks,
                    uint256 prevStakeLimit,
                    uint256 prevStakeBlockNumber
                ) {
                    StakeLimitState.Data memory stakeLimitData = STAKING_STATE_POSITION.getStorageStakeLimitStruct();
                    isStakingPaused = stakeLimitData.isStakingPaused();
                    isStakingLimitSet = stakeLimitData.isStakingLimitSet();
                    currentStakeLimit = _getCurrentStakeLimit(stakeLimitData);
                    maxStakeLimit = stakeLimitData.maxStakeLimit;
                    maxStakeLimitGrowthBlocks = stakeLimitData.maxStakeLimitGrowthBlocks;
                    prevStakeLimit = stakeLimitData.prevStakeLimit;
                    prevStakeBlockNumber = stakeLimitData.prevStakeBlockNumber;
                }
                /**
                * @notice Send funds to the pool
                * @dev Users are able to submit their funds by transacting to the fallback function.
                * Unlike vanilla Eth2.0 Deposit contract, accepting only 32-Ether transactions, Lido
                * accepts payments of any size. Submitted Ethers are stored in Buffer until someone calls
                * depositBufferedEther() and pushes them to the ETH2 Deposit contract.
                */
                function() external payable {
                    // protection against accidental submissions by calling non-existent function
                    require(msg.data.length == 0, "NON_EMPTY_DATA");
                    _submit(0);
                }
                /**
                * @notice Send funds to the pool with optional _referral parameter
                * @dev This function is alternative way to submit funds. Supports optional referral address.
                * @return Amount of StETH shares generated
                */
                function submit(address _referral) external payable returns (uint256) {
                    return _submit(_referral);
                }
                /**
                * @notice A payable function for execution layer rewards. Can be called only by ExecutionLayerRewardsVault contract
                * @dev We need a dedicated function because funds received by the default payable function
                * are treated as a user deposit
                */
                function receiveELRewards() external payable {
                    require(msg.sender == EL_REWARDS_VAULT_POSITION.getStorageAddress());
                    TOTAL_EL_REWARDS_COLLECTED_POSITION.setStorageUint256(
                        TOTAL_EL_REWARDS_COLLECTED_POSITION.getStorageUint256().add(msg.value));
                    emit ELRewardsReceived(msg.value);
                }
                /**
                * @notice Deposits buffered ethers to the official DepositContract.
                * @dev This function is separated from submit() to reduce the cost of sending funds.
                */
                function depositBufferedEther() external {
                    _auth(DEPOSIT_ROLE);
                    return _depositBufferedEther(DEFAULT_MAX_DEPOSITS_PER_CALL);
                }
                /**
                * @notice Deposits buffered ethers to the official DepositContract, making no more than `_maxDeposits` deposit calls.
                * @dev This function is separated from submit() to reduce the cost of sending funds.
                */
                function depositBufferedEther(uint256 _maxDeposits) external {
                    _auth(DEPOSIT_ROLE);
                    return _depositBufferedEther(_maxDeposits);
                }
                function burnShares(address _account, uint256 _sharesAmount)
                    external
                    authP(BURN_ROLE, arr(_account, _sharesAmount))
                    returns (uint256 newTotalShares)
                {
                    return _burnShares(_account, _sharesAmount);
                }
                /**
                * @notice Stop pool routine operations
                */
                function stop() external {
                    _auth(PAUSE_ROLE);
                    _stop();
                    _pauseStaking();
                }
                /**
                * @notice Resume pool routine operations
                * @dev Staking should be resumed manually after this call using the desired limits
                */
                function resume() external {
                    _auth(RESUME_ROLE);
                    _resume();
                    _resumeStaking();
                }
                /**
                * @notice Set fee rate to `_feeBasisPoints` basis points.
                * The fees are accrued when:
                * - oracles report staking results (beacon chain balance increase)
                * - validators gain execution layer rewards (priority fees and MEV)
                * @param _feeBasisPoints Fee rate, in basis points
                */
                function setFee(uint16 _feeBasisPoints) external {
                    _auth(MANAGE_FEE);
                    _setBPValue(FEE_POSITION, _feeBasisPoints);
                    emit FeeSet(_feeBasisPoints);
                }
                /**
                * @notice Set fee distribution
                * @param _treasuryFeeBasisPoints basis points go to the treasury,
                * @param _insuranceFeeBasisPoints basis points go to the insurance fund,
                * @param _operatorsFeeBasisPoints basis points go to node operators.
                * @dev The sum has to be 10 000.
                */
                function setFeeDistribution(
                    uint16 _treasuryFeeBasisPoints,
                    uint16 _insuranceFeeBasisPoints,
                    uint16 _operatorsFeeBasisPoints
                )
                    external
                {
                    _auth(MANAGE_FEE);
                    require(
                        TOTAL_BASIS_POINTS == uint256(_treasuryFeeBasisPoints)
                        .add(uint256(_insuranceFeeBasisPoints))
                        .add(uint256(_operatorsFeeBasisPoints)),
                        "FEES_DONT_ADD_UP"
                    );
                    _setBPValue(TREASURY_FEE_POSITION, _treasuryFeeBasisPoints);
                    _setBPValue(INSURANCE_FEE_POSITION, _insuranceFeeBasisPoints);
                    _setBPValue(NODE_OPERATORS_FEE_POSITION, _operatorsFeeBasisPoints);
                    emit FeeDistributionSet(_treasuryFeeBasisPoints, _insuranceFeeBasisPoints, _operatorsFeeBasisPoints);
                }
                /**
                * @notice Set Lido protocol contracts (oracle, treasury, insurance fund).
                *
                * @dev Oracle contract specified here is allowed to make
                * periodical updates of beacon stats
                * by calling pushBeacon. Treasury contract specified here is used
                * to accumulate the protocol treasury fee. Insurance fund contract
                * specified here is used to accumulate the protocol insurance fee.
                *
                * @param _oracle oracle contract
                * @param _treasury treasury contract
                * @param _insuranceFund insurance fund contract
                */
                function setProtocolContracts(
                    address _oracle,
                    address _treasury,
                    address _insuranceFund
                ) external {
                    _auth(MANAGE_PROTOCOL_CONTRACTS_ROLE);
                    _setProtocolContracts(_oracle, _treasury, _insuranceFund);
                }
                /**
                * @notice Set credentials to withdraw ETH on ETH 2.0 side after the phase 2 is launched to `_withdrawalCredentials`
                * @dev Note that setWithdrawalCredentials discards all unused signing keys as the signatures are invalidated.
                * @param _withdrawalCredentials withdrawal credentials field as defined in the Ethereum PoS consensus specs
                */
                function setWithdrawalCredentials(bytes32 _withdrawalCredentials) external {
                    _auth(MANAGE_WITHDRAWAL_KEY);
                    WITHDRAWAL_CREDENTIALS_POSITION.setStorageBytes32(_withdrawalCredentials);
                    getOperators().trimUnusedKeys();
                    emit WithdrawalCredentialsSet(_withdrawalCredentials);
                }
                /**
                * @dev Sets the address of LidoExecutionLayerRewardsVault contract
                * @param _executionLayerRewardsVault Execution layer rewards vault contract address
                */
                function setELRewardsVault(address _executionLayerRewardsVault) external {
                    _auth(SET_EL_REWARDS_VAULT_ROLE);
                    EL_REWARDS_VAULT_POSITION.setStorageAddress(_executionLayerRewardsVault);
                    emit ELRewardsVaultSet(_executionLayerRewardsVault);
                }
                /**
                * @dev Sets limit on amount of ETH to withdraw from execution layer rewards vault per LidoOracle report
                * @param _limitPoints limit in basis points to amount of ETH to withdraw per LidoOracle report
                */
                function setELRewardsWithdrawalLimit(uint16 _limitPoints) external {
                    _auth(SET_EL_REWARDS_WITHDRAWAL_LIMIT_ROLE);
                    _setBPValue(EL_REWARDS_WITHDRAWAL_LIMIT_POSITION, _limitPoints);
                    emit ELRewardsWithdrawalLimitSet(_limitPoints);
                }
                /**
                * @notice Updates beacon stats, collects rewards from LidoExecutionLayerRewardsVault and distributes all rewards if beacon balance increased
                * @dev periodically called by the Oracle contract
                * @param _beaconValidators number of Lido's keys in the beacon state
                * @param _beaconBalance summarized balance of Lido-controlled keys in wei
                */
                function handleOracleReport(uint256 _beaconValidators, uint256 _beaconBalance) external whenNotStopped {
                    require(msg.sender == getOracle(), "APP_AUTH_FAILED");
                    uint256 depositedValidators = DEPOSITED_VALIDATORS_POSITION.getStorageUint256();
                    require(_beaconValidators <= depositedValidators, "REPORTED_MORE_DEPOSITED");
                    uint256 beaconValidators = BEACON_VALIDATORS_POSITION.getStorageUint256();
                    // Since the calculation of funds in the ingress queue is based on the number of validators
                    // that are in a transient state (deposited but not seen on beacon yet), we can't decrease the previously
                    // reported number (we'll be unable to figure out who is in the queue and count them).
                    // See LIP-1 for details https://github.com/lidofinance/lido-improvement-proposals/blob/develop/LIPS/lip-1.md
                    require(_beaconValidators >= beaconValidators, "REPORTED_LESS_VALIDATORS");
                    uint256 appearedValidators = _beaconValidators.sub(beaconValidators);
                    // RewardBase is the amount of money that is not included in the reward calculation
                    // Just appeared validators * 32 added to the previously reported beacon balance
                    uint256 rewardBase = (appearedValidators.mul(DEPOSIT_SIZE)).add(BEACON_BALANCE_POSITION.getStorageUint256());
                    // Save the current beacon balance and validators to
                    // calculate rewards on the next push
                    BEACON_BALANCE_POSITION.setStorageUint256(_beaconBalance);
                    BEACON_VALIDATORS_POSITION.setStorageUint256(_beaconValidators);
                    // If LidoExecutionLayerRewardsVault address is not set just do as if there were no execution layer rewards at all
                    // Otherwise withdraw all rewards and put them to the buffer
                    // Thus, execution layer rewards are handled the same way as beacon rewards
                    uint256 executionLayerRewards;
                    address executionLayerRewardsVaultAddress = getELRewardsVault();
                    if (executionLayerRewardsVaultAddress != address(0)) {
                        executionLayerRewards = ILidoExecutionLayerRewardsVault(executionLayerRewardsVaultAddress).withdrawRewards(
                            (_getTotalPooledEther() * EL_REWARDS_WITHDRAWAL_LIMIT_POSITION.getStorageUint256()) / TOTAL_BASIS_POINTS
                        );
                        if (executionLayerRewards != 0) {
                            BUFFERED_ETHER_POSITION.setStorageUint256(_getBufferedEther().add(executionLayerRewards));
                        }
                    }
                    // Don’t mint/distribute any protocol fee on the non-profitable Lido oracle report
                    // (when beacon chain balance delta is zero or negative).
                    // See ADR #3 for details: https://research.lido.fi/t/rewards-distribution-after-the-merge-architecture-decision-record/1535
                    if (_beaconBalance > rewardBase) {
                        uint256 rewards = _beaconBalance.sub(rewardBase);
                        distributeFee(rewards.add(executionLayerRewards));
                    }
                }
                /**
                * @notice Send funds to recovery Vault. Overrides default AragonApp behaviour
                * @param _token Token to be sent to recovery vault
                */
                function transferToVault(address _token) external {
                    require(allowRecoverability(_token), "RECOVER_DISALLOWED");
                    address vault = getRecoveryVault();
                    require(vault != address(0), "RECOVER_VAULT_ZERO");
                    uint256 balance;
                    if (_token == ETH) {
                        balance = _getUnaccountedEther();
                        // Transfer replaced by call to prevent transfer gas amount issue
                        require(vault.call.value(balance)(), "RECOVER_TRANSFER_FAILED");
                    } else {
                        ERC20 token = ERC20(_token);
                        balance = token.staticBalanceOf(this);
                        // safeTransfer comes from overridden default implementation
                        require(token.safeTransfer(vault, balance), "RECOVER_TOKEN_TRANSFER_FAILED");
                    }
                    emit RecoverToVault(vault, _token, balance);
                }
                /**
                * @notice Returns staking rewards fee rate
                */
                function getFee() public view returns (uint16 feeBasisPoints) {
                    return uint16(FEE_POSITION.getStorageUint256());
                }
                /**
                * @notice Returns fee distribution proportion
                */
                function getFeeDistribution()
                    public
                    view
                    returns (
                        uint16 treasuryFeeBasisPoints,
                        uint16 insuranceFeeBasisPoints,
                        uint16 operatorsFeeBasisPoints
                    )
                {
                    treasuryFeeBasisPoints = uint16(TREASURY_FEE_POSITION.getStorageUint256());
                    insuranceFeeBasisPoints = uint16(INSURANCE_FEE_POSITION.getStorageUint256());
                    operatorsFeeBasisPoints = uint16(NODE_OPERATORS_FEE_POSITION.getStorageUint256());
                }
                /**
                * @notice Returns current credentials to withdraw ETH on ETH 2.0 side after the phase 2 is launched
                */
                function getWithdrawalCredentials() public view returns (bytes32) {
                    return WITHDRAWAL_CREDENTIALS_POSITION.getStorageBytes32();
                }
                /**
                * @notice Get the amount of Ether temporary buffered on this contract balance
                * @dev Buffered balance is kept on the contract from the moment the funds are received from user
                * until the moment they are actually sent to the official Deposit contract.
                * @return amount of buffered funds in wei
                */
                function getBufferedEther() external view returns (uint256) {
                    return _getBufferedEther();
                }
                /**
                * @notice Get total amount of execution layer rewards collected to Lido contract
                * @dev Ether got through LidoExecutionLayerRewardsVault is kept on this contract's balance the same way
                * as other buffered Ether is kept (until it gets deposited)
                * @return amount of funds received as execution layer rewards (in wei)
                */
                function getTotalELRewardsCollected() external view returns (uint256) {
                    return TOTAL_EL_REWARDS_COLLECTED_POSITION.getStorageUint256();
                }
                /**
                * @notice Get limit in basis points to amount of ETH to withdraw per LidoOracle report
                * @return limit in basis points to amount of ETH to withdraw per LidoOracle report
                */
                function getELRewardsWithdrawalLimit() external view returns (uint256) {
                    return EL_REWARDS_WITHDRAWAL_LIMIT_POSITION.getStorageUint256();
                }
                /**
                * @notice Gets deposit contract handle
                */
                function getDepositContract() public view returns (IDepositContract) {
                    return IDepositContract(DEPOSIT_CONTRACT_POSITION.getStorageAddress());
                }
                /**
                * @notice Gets authorized oracle address
                * @return address of oracle contract
                */
                function getOracle() public view returns (address) {
                    return ORACLE_POSITION.getStorageAddress();
                }
                /**
                * @notice Gets node operators registry interface handle
                */
                function getOperators() public view returns (INodeOperatorsRegistry) {
                    return INodeOperatorsRegistry(NODE_OPERATORS_REGISTRY_POSITION.getStorageAddress());
                }
                /**
                * @notice Returns the treasury address
                */
                function getTreasury() public view returns (address) {
                    return TREASURY_POSITION.getStorageAddress();
                }
                /**
                * @notice Returns the insurance fund address
                */
                function getInsuranceFund() public view returns (address) {
                    return INSURANCE_FUND_POSITION.getStorageAddress();
                }
                /**
                * @notice Returns the key values related to Beacon-side
                * @return depositedValidators - number of deposited validators
                * @return beaconValidators - number of Lido's validators visible in the Beacon state, reported by oracles
                * @return beaconBalance - total amount of Beacon-side Ether (sum of all the balances of Lido validators)
                */
                function getBeaconStat() public view returns (uint256 depositedValidators, uint256 beaconValidators, uint256 beaconBalance) {
                    depositedValidators = DEPOSITED_VALIDATORS_POSITION.getStorageUint256();
                    beaconValidators = BEACON_VALIDATORS_POSITION.getStorageUint256();
                    beaconBalance = BEACON_BALANCE_POSITION.getStorageUint256();
                }
                /**
                * @notice Returns address of the contract set as LidoExecutionLayerRewardsVault
                */
                function getELRewardsVault() public view returns (address) {
                    return EL_REWARDS_VAULT_POSITION.getStorageAddress();
                }
                /**
                * @dev Internal function to set authorized oracle address
                * @param _oracle oracle contract
                */
                function _setProtocolContracts(address _oracle, address _treasury, address _insuranceFund) internal {
                    require(_oracle != address(0), "ORACLE_ZERO_ADDRESS");
                    require(_treasury != address(0), "TREASURY_ZERO_ADDRESS");
                    require(_insuranceFund != address(0), "INSURANCE_FUND_ZERO_ADDRESS");
                    ORACLE_POSITION.setStorageAddress(_oracle);
                    TREASURY_POSITION.setStorageAddress(_treasury);
                    INSURANCE_FUND_POSITION.setStorageAddress(_insuranceFund);
                    emit ProtocolContactsSet(_oracle, _treasury, _insuranceFund);
                }
                /**
                * @dev Process user deposit, mints liquid tokens and increase the pool buffer
                * @param _referral address of referral.
                * @return amount of StETH shares generated
                */
                function _submit(address _referral) internal returns (uint256) {
                    require(msg.value != 0, "ZERO_DEPOSIT");
                    StakeLimitState.Data memory stakeLimitData = STAKING_STATE_POSITION.getStorageStakeLimitStruct();
                    require(!stakeLimitData.isStakingPaused(), "STAKING_PAUSED");
                    if (stakeLimitData.isStakingLimitSet()) {
                        uint256 currentStakeLimit = stakeLimitData.calculateCurrentStakeLimit();
                        require(msg.value <= currentStakeLimit, "STAKE_LIMIT");
                        STAKING_STATE_POSITION.setStorageStakeLimitStruct(
                            stakeLimitData.updatePrevStakeLimit(currentStakeLimit - msg.value)
                        );
                    }
                    uint256 sharesAmount = getSharesByPooledEth(msg.value);
                    if (sharesAmount == 0) {
                        // totalControlledEther is 0: either the first-ever deposit or complete slashing
                        // assume that shares correspond to Ether 1-to-1
                        sharesAmount = msg.value;
                    }
                    _mintShares(msg.sender, sharesAmount);
                    BUFFERED_ETHER_POSITION.setStorageUint256(_getBufferedEther().add(msg.value));
                    emit Submitted(msg.sender, msg.value, _referral);
                    _emitTransferAfterMintingShares(msg.sender, sharesAmount);
                    return sharesAmount;
                }
                /**
                * @dev Emits {Transfer} and {TransferShares} events where `from` is 0 address. Indicates mint events.
                */
                function _emitTransferAfterMintingShares(address _to, uint256 _sharesAmount) internal {
                    emit Transfer(address(0), _to, getPooledEthByShares(_sharesAmount));
                    emit TransferShares(address(0), _to, _sharesAmount);
                }
                /**
                * @dev Deposits buffered eth to the DepositContract and assigns chunked deposits to node operators
                */
                function _depositBufferedEther(uint256 _maxDeposits) internal whenNotStopped {
                    uint256 buffered = _getBufferedEther();
                    if (buffered >= DEPOSIT_SIZE) {
                        uint256 unaccounted = _getUnaccountedEther();
                        uint256 numDeposits = buffered.div(DEPOSIT_SIZE);
                        _markAsUnbuffered(_ETH2Deposit(numDeposits < _maxDeposits ? numDeposits : _maxDeposits));
                        assert(_getUnaccountedEther() == unaccounted);
                    }
                }
                /**
                * @dev Performs deposits to the ETH 2.0 side
                * @param _numDeposits Number of deposits to perform
                * @return actually deposited Ether amount
                */
                function _ETH2Deposit(uint256 _numDeposits) internal returns (uint256) {
                    (bytes memory pubkeys, bytes memory signatures) = getOperators().assignNextSigningKeys(_numDeposits);
                    if (pubkeys.length == 0) {
                        return 0;
                    }
                    require(pubkeys.length.mod(PUBKEY_LENGTH) == 0, "REGISTRY_INCONSISTENT_PUBKEYS_LEN");
                    require(signatures.length.mod(SIGNATURE_LENGTH) == 0, "REGISTRY_INCONSISTENT_SIG_LEN");
                    uint256 numKeys = pubkeys.length.div(PUBKEY_LENGTH);
                    require(numKeys == signatures.length.div(SIGNATURE_LENGTH), "REGISTRY_INCONSISTENT_SIG_COUNT");
                    for (uint256 i = 0; i < numKeys; ++i) {
                        bytes memory pubkey = BytesLib.slice(pubkeys, i * PUBKEY_LENGTH, PUBKEY_LENGTH);
                        bytes memory signature = BytesLib.slice(signatures, i * SIGNATURE_LENGTH, SIGNATURE_LENGTH);
                        _stake(pubkey, signature);
                    }
                    DEPOSITED_VALIDATORS_POSITION.setStorageUint256(
                        DEPOSITED_VALIDATORS_POSITION.getStorageUint256().add(numKeys)
                    );
                    return numKeys.mul(DEPOSIT_SIZE);
                }
                /**
                * @dev Invokes a deposit call to the official Deposit contract
                * @param _pubkey Validator to stake for
                * @param _signature Signature of the deposit call
                */
                function _stake(bytes memory _pubkey, bytes memory _signature) internal {
                    bytes32 withdrawalCredentials = getWithdrawalCredentials();
                    require(withdrawalCredentials != 0, "EMPTY_WITHDRAWAL_CREDENTIALS");
                    uint256 value = DEPOSIT_SIZE;
                    // The following computations and Merkle tree-ization will make official Deposit contract happy
                    uint256 depositAmount = value.div(DEPOSIT_AMOUNT_UNIT);
                    assert(depositAmount.mul(DEPOSIT_AMOUNT_UNIT) == value);    // properly rounded
                    // Compute deposit data root (`DepositData` hash tree root) according to deposit_contract.sol
                    bytes32 pubkeyRoot = sha256(_pad64(_pubkey));
                    bytes32 signatureRoot = sha256(
                        abi.encodePacked(
                            sha256(BytesLib.slice(_signature, 0, 64)),
                            sha256(_pad64(BytesLib.slice(_signature, 64, SIGNATURE_LENGTH.sub(64))))
                        )
                    );
                    bytes32 depositDataRoot = sha256(
                        abi.encodePacked(
                            sha256(abi.encodePacked(pubkeyRoot, withdrawalCredentials)),
                            sha256(abi.encodePacked(_toLittleEndian64(depositAmount), signatureRoot))
                        )
                    );
                    uint256 targetBalance = address(this).balance.sub(value);
                    getDepositContract().deposit.value(value)(
                        _pubkey, abi.encodePacked(withdrawalCredentials), _signature, depositDataRoot);
                    require(address(this).balance == targetBalance, "EXPECTING_DEPOSIT_TO_HAPPEN");
                }
                /**
                * @dev Distributes fee portion of the rewards by minting and distributing corresponding amount of liquid tokens.
                * @param _totalRewards Total rewards accrued on the Ethereum 2.0 side in wei
                */
                function distributeFee(uint256 _totalRewards) internal {
                    // We need to take a defined percentage of the reported reward as a fee, and we do
                    // this by minting new token shares and assigning them to the fee recipients (see
                    // StETH docs for the explanation of the shares mechanics). The staking rewards fee
                    // is defined in basis points (1 basis point is equal to 0.01%, 10000 (TOTAL_BASIS_POINTS) is 100%).
                    //
                    // Since we've increased totalPooledEther by _totalRewards (which is already
                    // performed by the time this function is called), the combined cost of all holders'
                    // shares has became _totalRewards StETH tokens more, effectively splitting the reward
                    // between each token holder proportionally to their token share.
                    //
                    // Now we want to mint new shares to the fee recipient, so that the total cost of the
                    // newly-minted shares exactly corresponds to the fee taken:
                    //
                    // shares2mint * newShareCost = (_totalRewards * feeBasis) / TOTAL_BASIS_POINTS
                    // newShareCost = newTotalPooledEther / (prevTotalShares + shares2mint)
                    //
                    // which follows to:
                    //
                    //                        _totalRewards * feeBasis * prevTotalShares
                    // shares2mint = --------------------------------------------------------------
                    //                 (newTotalPooledEther * TOTAL_BASIS_POINTS) - (feeBasis * _totalRewards)
                    //
                    // The effect is that the given percentage of the reward goes to the fee recipient, and
                    // the rest of the reward is distributed between token holders proportionally to their
                    // token shares.
                    uint256 feeBasis = getFee();
                    uint256 shares2mint = (
                        _totalRewards.mul(feeBasis).mul(_getTotalShares())
                        .div(
                            _getTotalPooledEther().mul(TOTAL_BASIS_POINTS)
                            .sub(feeBasis.mul(_totalRewards))
                        )
                    );
                    // Mint the calculated amount of shares to this contract address. This will reduce the
                    // balances of the holders, as if the fee was taken in parts from each of them.
                    _mintShares(address(this), shares2mint);
                    (,uint16 insuranceFeeBasisPoints, uint16 operatorsFeeBasisPoints) = getFeeDistribution();
                    uint256 toInsuranceFund = shares2mint.mul(insuranceFeeBasisPoints).div(TOTAL_BASIS_POINTS);
                    address insuranceFund = getInsuranceFund();
                    _transferShares(address(this), insuranceFund, toInsuranceFund);
                    _emitTransferAfterMintingShares(insuranceFund, toInsuranceFund);
                    uint256 distributedToOperatorsShares = _distributeNodeOperatorsReward(
                        shares2mint.mul(operatorsFeeBasisPoints).div(TOTAL_BASIS_POINTS)
                    );
                    // Transfer the rest of the fee to treasury
                    uint256 toTreasury = shares2mint.sub(toInsuranceFund).sub(distributedToOperatorsShares);
                    address treasury = getTreasury();
                    _transferShares(address(this), treasury, toTreasury);
                    _emitTransferAfterMintingShares(treasury, toTreasury);
                }
                /**
                *  @dev Internal function to distribute reward to node operators
                *  @param _sharesToDistribute amount of shares to distribute
                *  @return actual amount of shares that was transferred to node operators as a reward
                */
                function _distributeNodeOperatorsReward(uint256 _sharesToDistribute) internal returns (uint256 distributed) {
                    (address[] memory recipients, uint256[] memory shares) = getOperators().getRewardsDistribution(_sharesToDistribute);
                    assert(recipients.length == shares.length);
                    distributed = 0;
                    for (uint256 idx = 0; idx < recipients.length; ++idx) {
                        _transferShares(
                            address(this),
                            recipients[idx],
                            shares[idx]
                        );
                        _emitTransferAfterMintingShares(recipients[idx], shares[idx]);
                        distributed = distributed.add(shares[idx]);
                    }
                }
                /**
                * @dev Records a deposit to the deposit_contract.deposit function
                * @param _amount Total amount deposited to the ETH 2.0 side
                */
                function _markAsUnbuffered(uint256 _amount) internal {
                    BUFFERED_ETHER_POSITION.setStorageUint256(
                        BUFFERED_ETHER_POSITION.getStorageUint256().sub(_amount));
                    emit Unbuffered(_amount);
                }
                /**
                * @dev Write a value nominated in basis points
                */
                function _setBPValue(bytes32 _slot, uint16 _value) internal {
                    require(_value <= TOTAL_BASIS_POINTS, "VALUE_OVER_100_PERCENT");
                    _slot.setStorageUint256(uint256(_value));
                }
                /**
                * @dev Gets the amount of Ether temporary buffered on this contract balance
                */
                function _getBufferedEther() internal view returns (uint256) {
                    uint256 buffered = BUFFERED_ETHER_POSITION.getStorageUint256();
                    assert(address(this).balance >= buffered);
                    return buffered;
                }
                /**
                * @dev Gets unaccounted (excess) Ether on this contract balance
                */
                function _getUnaccountedEther() internal view returns (uint256) {
                    return address(this).balance.sub(_getBufferedEther());
                }
                /**
                * @dev Calculates and returns the total base balance (multiple of 32) of validators in transient state,
                *      i.e. submitted to the official Deposit contract but not yet visible in the beacon state.
                * @return transient balance in wei (1e-18 Ether)
                */
                function _getTransientBalance() internal view returns (uint256) {
                    uint256 depositedValidators = DEPOSITED_VALIDATORS_POSITION.getStorageUint256();
                    uint256 beaconValidators = BEACON_VALIDATORS_POSITION.getStorageUint256();
                    // beaconValidators can never be less than deposited ones.
                    assert(depositedValidators >= beaconValidators);
                    return depositedValidators.sub(beaconValidators).mul(DEPOSIT_SIZE);
                }
                /**
                * @dev Gets the total amount of Ether controlled by the system
                * @return total balance in wei
                */
                function _getTotalPooledEther() internal view returns (uint256) {
                    return _getBufferedEther().add(
                        BEACON_BALANCE_POSITION.getStorageUint256()
                    ).add(_getTransientBalance());
                }
                /**
                * @dev Padding memory array with zeroes up to 64 bytes on the right
                * @param _b Memory array of size 32 .. 64
                */
                function _pad64(bytes memory _b) internal pure returns (bytes memory) {
                    assert(_b.length >= 32 && _b.length <= 64);
                    if (64 == _b.length)
                        return _b;
                    bytes memory zero32 = new bytes(32);
                    assembly { mstore(add(zero32, 0x20), 0) }
                    if (32 == _b.length)
                        return BytesLib.concat(_b, zero32);
                    else
                        return BytesLib.concat(_b, BytesLib.slice(zero32, 0, uint256(64).sub(_b.length)));
                }
                /**
                * @dev Converting value to little endian bytes and padding up to 32 bytes on the right
                * @param _value Number less than `2**64` for compatibility reasons
                */
                function _toLittleEndian64(uint256 _value) internal pure returns (uint256 result) {
                    result = 0;
                    uint256 temp_value = _value;
                    for (uint256 i = 0; i < 8; ++i) {
                        result = (result << 8) | (temp_value & 0xFF);
                        temp_value >>= 8;
                    }
                    assert(0 == temp_value);    // fully converted
                    result <<= (24 * 8);
                }
                function _pauseStaking() internal {
                    STAKING_STATE_POSITION.setStorageStakeLimitStruct(
                        STAKING_STATE_POSITION.getStorageStakeLimitStruct().setStakeLimitPauseState(true)
                    );
                    emit StakingPaused();
                }
                function _resumeStaking() internal {
                    STAKING_STATE_POSITION.setStorageStakeLimitStruct(
                        STAKING_STATE_POSITION.getStorageStakeLimitStruct().setStakeLimitPauseState(false)
                    );
                    emit StakingResumed();
                }
                function _getCurrentStakeLimit(StakeLimitState.Data memory _stakeLimitData) internal view returns(uint256) {
                    if (_stakeLimitData.isStakingPaused()) {
                        return 0;
                    }
                    if (!_stakeLimitData.isStakingLimitSet()) {
                        return uint256(-1);
                    }
                    return _stakeLimitData.calculateCurrentStakeLimit();
                }
                /**
                * @dev Size-efficient analog of the `auth(_role)` modifier
                * @param _role Permission name
                */
                function _auth(bytes32 _role) internal view auth(_role) {
                    // no-op
                }
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            import "./AppStorage.sol";
            import "../acl/ACLSyntaxSugar.sol";
            import "../common/Autopetrified.sol";
            import "../common/ConversionHelpers.sol";
            import "../common/ReentrancyGuard.sol";
            import "../common/VaultRecoverable.sol";
            import "../evmscript/EVMScriptRunner.sol";
            // Contracts inheriting from AragonApp are, by default, immediately petrified upon deployment so
            // that they can never be initialized.
            // Unless overriden, this behaviour enforces those contracts to be usable only behind an AppProxy.
            // ReentrancyGuard, EVMScriptRunner, and ACLSyntaxSugar are not directly used by this contract, but
            // are included so that they are automatically usable by subclassing contracts
            contract AragonApp is AppStorage, Autopetrified, VaultRecoverable, ReentrancyGuard, EVMScriptRunner, ACLSyntaxSugar {
                string private constant ERROR_AUTH_FAILED = "APP_AUTH_FAILED";
                modifier auth(bytes32 _role) {
                    require(canPerform(msg.sender, _role, new uint256[](0)), ERROR_AUTH_FAILED);
                    _;
                }
                modifier authP(bytes32 _role, uint256[] _params) {
                    require(canPerform(msg.sender, _role, _params), ERROR_AUTH_FAILED);
                    _;
                }
                /**
                * @dev Check whether an action can be performed by a sender for a particular role on this app
                * @param _sender Sender of the call
                * @param _role Role on this app
                * @param _params Permission params for the role
                * @return Boolean indicating whether the sender has the permissions to perform the action.
                *         Always returns false if the app hasn't been initialized yet.
                */
                function canPerform(address _sender, bytes32 _role, uint256[] _params) public view returns (bool) {
                    if (!hasInitialized()) {
                        return false;
                    }
                    IKernel linkedKernel = kernel();
                    if (address(linkedKernel) == address(0)) {
                        return false;
                    }
                    return linkedKernel.hasPermission(
                        _sender,
                        address(this),
                        _role,
                        ConversionHelpers.dangerouslyCastUintArrayToBytes(_params)
                    );
                }
                /**
                * @dev Get the recovery vault for the app
                * @return Recovery vault address for the app
                */
                function getRecoveryVault() public view returns (address) {
                    // Funds recovery via a vault is only available when used with a kernel
                    return kernel().getRecoveryVault(); // if kernel is not set, it will revert
                }
            }
            // See https://github.com/OpenZeppelin/openzeppelin-solidity/blob/d51e38758e1d985661534534d5c61e27bece5042/contracts/math/SafeMath.sol
            // Adapted to use pragma ^0.4.24 and satisfy our linter rules
            pragma solidity ^0.4.24;
            /**
             * @title SafeMath
             * @dev Math operations with safety checks that revert on error
             */
            library SafeMath {
                string private constant ERROR_ADD_OVERFLOW = "MATH_ADD_OVERFLOW";
                string private constant ERROR_SUB_UNDERFLOW = "MATH_SUB_UNDERFLOW";
                string private constant ERROR_MUL_OVERFLOW = "MATH_MUL_OVERFLOW";
                string private constant ERROR_DIV_ZERO = "MATH_DIV_ZERO";
                /**
                * @dev Multiplies two numbers, reverts on overflow.
                */
                function mul(uint256 _a, uint256 _b) internal pure returns (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-solidity/pull/522
                    if (_a == 0) {
                        return 0;
                    }
                    uint256 c = _a * _b;
                    require(c / _a == _b, ERROR_MUL_OVERFLOW);
                    return c;
                }
                /**
                * @dev Integer division of two numbers truncating the quotient, reverts on division by zero.
                */
                function div(uint256 _a, uint256 _b) internal pure returns (uint256) {
                    require(_b > 0, ERROR_DIV_ZERO); // Solidity only automatically asserts when dividing by 0
                    uint256 c = _a / _b;
                    // assert(_a == _b * c + _a % _b); // There is no case in which this doesn't hold
                    return c;
                }
                /**
                * @dev Subtracts two numbers, reverts on overflow (i.e. if subtrahend is greater than minuend).
                */
                function sub(uint256 _a, uint256 _b) internal pure returns (uint256) {
                    require(_b <= _a, ERROR_SUB_UNDERFLOW);
                    uint256 c = _a - _b;
                    return c;
                }
                /**
                * @dev Adds two numbers, reverts on overflow.
                */
                function add(uint256 _a, uint256 _b) internal pure returns (uint256) {
                    uint256 c = _a + _b;
                    require(c >= _a, ERROR_ADD_OVERFLOW);
                    return c;
                }
                /**
                * @dev Divides two numbers and returns the remainder (unsigned integer modulo),
                * reverts when dividing by zero.
                */
                function mod(uint256 a, uint256 b) internal pure returns (uint256) {
                    require(b != 0, ERROR_DIV_ZERO);
                    return a % b;
                }
            }
            // See https://github.com/OpenZeppelin/openzeppelin-solidity/blob/d51e38758e1d985661534534d5c61e27bece5042/contracts/math/SafeMath.sol
            // Adapted for uint64, pragma ^0.4.24, and satisfying our linter rules
            // Also optimized the mul() implementation, see https://github.com/aragon/aragonOS/pull/417
            pragma solidity ^0.4.24;
            /**
             * @title SafeMath64
             * @dev Math operations for uint64 with safety checks that revert on error
             */
            library SafeMath64 {
                string private constant ERROR_ADD_OVERFLOW = "MATH64_ADD_OVERFLOW";
                string private constant ERROR_SUB_UNDERFLOW = "MATH64_SUB_UNDERFLOW";
                string private constant ERROR_MUL_OVERFLOW = "MATH64_MUL_OVERFLOW";
                string private constant ERROR_DIV_ZERO = "MATH64_DIV_ZERO";
                /**
                * @dev Multiplies two numbers, reverts on overflow.
                */
                function mul(uint64 _a, uint64 _b) internal pure returns (uint64) {
                    uint256 c = uint256(_a) * uint256(_b);
                    require(c < 0x010000000000000000, ERROR_MUL_OVERFLOW); // 2**64 (less gas this way)
                    return uint64(c);
                }
                /**
                * @dev Integer division of two numbers truncating the quotient, reverts on division by zero.
                */
                function div(uint64 _a, uint64 _b) internal pure returns (uint64) {
                    require(_b > 0, ERROR_DIV_ZERO); // Solidity only automatically asserts when dividing by 0
                    uint64 c = _a / _b;
                    // assert(_a == _b * c + _a % _b); // There is no case in which this doesn't hold
                    return c;
                }
                /**
                * @dev Subtracts two numbers, reverts on overflow (i.e. if subtrahend is greater than minuend).
                */
                function sub(uint64 _a, uint64 _b) internal pure returns (uint64) {
                    require(_b <= _a, ERROR_SUB_UNDERFLOW);
                    uint64 c = _a - _b;
                    return c;
                }
                /**
                * @dev Adds two numbers, reverts on overflow.
                */
                function add(uint64 _a, uint64 _b) internal pure returns (uint64) {
                    uint64 c = _a + _b;
                    require(c >= _a, ERROR_ADD_OVERFLOW);
                    return c;
                }
                /**
                * @dev Divides two numbers and returns the remainder (unsigned integer modulo),
                * reverts when dividing by zero.
                */
                function mod(uint64 a, uint64 b) internal pure returns (uint64) {
                    require(b != 0, ERROR_DIV_ZERO);
                    return a % b;
                }
            }
            /*
             * @title Solidity Bytes Arrays Utils
             * @author Gonçalo Sá <[email protected]>
             *
             * @dev Bytes tightly packed arrays utility library for ethereum contracts written in Solidity.
             *      The library lets you concatenate, slice and type cast bytes arrays both in memory and storage.
             */
            pragma solidity ^0.4.19;
            library BytesLib {
                function concat(bytes memory _preBytes, bytes memory _postBytes) internal pure returns (bytes) {
                    bytes memory tempBytes;
                    assembly {
                        // Get a location of some free memory and store it in tempBytes as
                        // Solidity does for memory variables.
                        tempBytes := mload(0x40)
                        // Store the length of the first bytes array at the beginning of
                        // the memory for tempBytes.
                        let length := mload(_preBytes)
                        mstore(tempBytes, length)
                        // Maintain a memory counter for the current write location in the
                        // temp bytes array by adding the 32 bytes for the array length to
                        // the starting location.
                        let mc := add(tempBytes, 0x20)
                        // Stop copying when the memory counter reaches the length of the
                        // first bytes array.
                        let end := add(mc, length)
                        for {
                            // Initialize a copy counter to the start of the _preBytes data,
                            // 32 bytes into its memory.
                            let cc := add(_preBytes, 0x20)
                        } lt(mc, end) {
                            // Increase both counters by 32 bytes each iteration.
                            mc := add(mc, 0x20)
                            cc := add(cc, 0x20)
                        } {
                            // Write the _preBytes data into the tempBytes memory 32 bytes
                            // at a time.
                            mstore(mc, mload(cc))
                        }
                        // Add the length of _postBytes to the current length of tempBytes
                        // and store it as the new length in the first 32 bytes of the
                        // tempBytes memory.
                        length := mload(_postBytes)
                        mstore(tempBytes, add(length, mload(tempBytes)))
                        // Move the memory counter back from a multiple of 0x20 to the
                        // actual end of the _preBytes data.
                        mc := end
                        // Stop copying when the memory counter reaches the new combined
                        // length of the arrays.
                        end := add(mc, length)
                        for {
                            let cc := add(_postBytes, 0x20)
                        } lt(mc, end) {
                            mc := add(mc, 0x20)
                            cc := add(cc, 0x20)
                        } {
                            mstore(mc, mload(cc))
                        }
                        // Update the free-memory pointer by padding our last write location
                        // to 32 bytes: add 31 bytes to the end of tempBytes to move to the
                        // next 32 byte block, then round down to the nearest multiple of
                        // 32. If the sum of the length of the two arrays is zero then add 
                        // one before rounding down to leave a blank 32 bytes (the length block with 0).
                        mstore(0x40, and(
                          add(add(end, iszero(add(length, mload(_preBytes)))), 31),
                          not(31) // Round down to the nearest 32 bytes.
                        ))
                    }
                    return tempBytes;
                }
                function concatStorage(bytes storage _preBytes, bytes memory _postBytes) internal {
                    assembly {
                        // Read the first 32 bytes of _preBytes storage, which is the length
                        // of the array. (We don't need to use the offset into the slot
                        // because arrays use the entire slot.)
                        let fslot := sload(_preBytes_slot)
                        // Arrays of 31 bytes or less have an even value in their slot,
                        // while longer arrays have an odd value. The actual length is
                        // the slot divided by two for odd values, and the lowest order
                        // byte divided by two for even values.
                        // If the slot is even, bitwise and the slot with 255 and divide by
                        // two to get the length. If the slot is odd, bitwise and the slot
                        // with -1 and divide by two.
                        let slength := div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
                        let mlength := mload(_postBytes)
                        let newlength := add(slength, mlength)
                        // slength can contain both the length and contents of the array
                        // if length < 32 bytes so let's prepare for that
                        // v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storage
                        switch add(lt(slength, 32), lt(newlength, 32))
                        case 2 {
                            // Since the new array still fits in the slot, we just need to
                            // update the contents of the slot.
                            // uint256(bytes_storage) = uint256(bytes_storage) + uint256(bytes_memory) + new_length
                            sstore(
                                _preBytes_slot,
                                // all the modifications to the slot are inside this
                                // next block
                                add(
                                    // we can just add to the slot contents because the
                                    // bytes we want to change are the LSBs
                                    fslot,
                                    add(
                                        mul(
                                            div(
                                                // load the bytes from memory
                                                mload(add(_postBytes, 0x20)),
                                                // zero all bytes to the right
                                                exp(0x100, sub(32, mlength))
                                            ),
                                            // and now shift left the number of bytes to
                                            // leave space for the length in the slot
                                            exp(0x100, sub(32, newlength))
                                        ),
                                        // increase length by the double of the memory
                                        // bytes length
                                        mul(mlength, 2)
                                    )
                                )
                            )
                        }
                        case 1 {
                            // The stored value fits in the slot, but the combined value
                            // will exceed it.
                            // get the keccak hash to get the contents of the array
                            mstore(0x0, _preBytes_slot)
                            let sc := add(keccak256(0x0, 0x20), div(slength, 32))
                            // save new length
                            sstore(_preBytes_slot, add(mul(newlength, 2), 1))
                            // The contents of the _postBytes array start 32 bytes into
                            // the structure. Our first read should obtain the `submod`
                            // bytes that can fit into the unused space in the last word
                            // of the stored array. To get this, we read 32 bytes starting
                            // from `submod`, so the data we read overlaps with the array
                            // contents by `submod` bytes. Masking the lowest-order
                            // `submod` bytes allows us to add that value directly to the
                            // stored value.
                            let submod := sub(32, slength)
                            let mc := add(_postBytes, submod)
                            let end := add(_postBytes, mlength)
                            let mask := sub(exp(0x100, submod), 1)
                            sstore(
                                sc,
                                add(
                                    and(
                                        fslot,
                                        0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff00
                                    ),
                                    and(mload(mc), mask)
                                )
                            )
                            for {
                                mc := add(mc, 0x20)
                                sc := add(sc, 1)
                            } lt(mc, end) {
                                sc := add(sc, 1)
                                mc := add(mc, 0x20)
                            } {
                                sstore(sc, mload(mc))
                            }
                            mask := exp(0x100, sub(mc, end))
                            sstore(sc, mul(div(mload(mc), mask), mask))
                        }
                        default {
                            // get the keccak hash to get the contents of the array
                            mstore(0x0, _preBytes_slot)
                            // Start copying to the last used word of the stored array.
                            let sc := add(keccak256(0x0, 0x20), div(slength, 32))
                            // save new length
                            sstore(_preBytes_slot, add(mul(newlength, 2), 1))
                            // Copy over the first `submod` bytes of the new data as in
                            // case 1 above.
                            let slengthmod := mod(slength, 32)
                            let mlengthmod := mod(mlength, 32)
                            let submod := sub(32, slengthmod)
                            let mc := add(_postBytes, submod)
                            let end := add(_postBytes, mlength)
                            let mask := sub(exp(0x100, submod), 1)
                            sstore(sc, add(sload(sc), and(mload(mc), mask)))
                            
                            for { 
                                sc := add(sc, 1)
                                mc := add(mc, 0x20)
                            } lt(mc, end) {
                                sc := add(sc, 1)
                                mc := add(mc, 0x20)
                            } {
                                sstore(sc, mload(mc))
                            }
                            mask := exp(0x100, sub(mc, end))
                            sstore(sc, mul(div(mload(mc), mask), mask))
                        }
                    }
                }
                function slice(bytes _bytes, uint _start, uint _length) internal  pure returns (bytes) {
                    require(_bytes.length >= (_start + _length));
                    bytes memory tempBytes;
                    assembly {
                        switch iszero(_length)
                        case 0 {
                            // Get a location of some free memory and store it in tempBytes as
                            // Solidity does for memory variables.
                            tempBytes := mload(0x40)
                            // The first word of the slice result is potentially a partial
                            // word read from the original array. To read it, we calculate
                            // the length of that partial word and start copying that many
                            // bytes into the array. The first word we copy will start with
                            // data we don't care about, but the last `lengthmod` bytes will
                            // land at the beginning of the contents of the new array. When
                            // we're done copying, we overwrite the full first word with
                            // the actual length of the slice.
                            let lengthmod := and(_length, 31)
                            // The multiplication in the next line is necessary
                            // because when slicing multiples of 32 bytes (lengthmod == 0)
                            // the following copy loop was copying the origin's length
                            // and then ending prematurely not copying everything it should.
                            let mc := add(add(tempBytes, lengthmod), mul(0x20, iszero(lengthmod)))
                            let end := add(mc, _length)
                            for {
                                // The multiplication in the next line has the same exact purpose
                                // as the one above.
                                let cc := add(add(add(_bytes, lengthmod), mul(0x20, iszero(lengthmod))), _start)
                            } lt(mc, end) {
                                mc := add(mc, 0x20)
                                cc := add(cc, 0x20)
                            } {
                                mstore(mc, mload(cc))
                            }
                            mstore(tempBytes, _length)
                            //update free-memory pointer
                            //allocating the array padded to 32 bytes like the compiler does now
                            mstore(0x40, and(add(mc, 31), not(31)))
                        }
                        //if we want a zero-length slice let's just return a zero-length array
                        default {
                            tempBytes := mload(0x40)
                            mstore(0x40, add(tempBytes, 0x20))
                        }
                    }
                    return tempBytes;
                }
                function toAddress(bytes _bytes, uint _start) internal  pure returns (address) {
                    require(_bytes.length >= (_start + 20));
                    address tempAddress;
                    assembly {
                        tempAddress := div(mload(add(add(_bytes, 0x20), _start)), 0x1000000000000000000000000)
                    }
                    return tempAddress;
                }
                function toUint8(bytes _bytes, uint _start) internal  pure returns (uint8) {
                    require(_bytes.length >= (_start + 1));
                    uint8 tempUint;
                    assembly {
                        tempUint := mload(add(add(_bytes, 0x1), _start))
                    }
                    return tempUint;
                }
                function toUint16(bytes _bytes, uint _start) internal  pure returns (uint16) {
                    require(_bytes.length >= (_start + 2));
                    uint16 tempUint;
                    assembly {
                        tempUint := mload(add(add(_bytes, 0x2), _start))
                    }
                    return tempUint;
                }
                function toUint32(bytes _bytes, uint _start) internal  pure returns (uint32) {
                    require(_bytes.length >= (_start + 4));
                    uint32 tempUint;
                    assembly {
                        tempUint := mload(add(add(_bytes, 0x4), _start))
                    }
                    return tempUint;
                }
                function toUint(bytes _bytes, uint _start) internal  pure returns (uint256) {
                    require(_bytes.length >= (_start + 32));
                    uint256 tempUint;
                    assembly {
                        tempUint := mload(add(add(_bytes, 0x20), _start))
                    }
                    return tempUint;
                }
                function toBytes32(bytes _bytes, uint _start) internal  pure returns (bytes32) {
                    require(_bytes.length >= (_start + 32));
                    bytes32 tempBytes32;
                    assembly {
                        tempBytes32 := mload(add(add(_bytes, 0x20), _start))
                    }
                    return tempBytes32;
                }
                function equal(bytes memory _preBytes, bytes memory _postBytes) internal pure returns (bool) {
                    bool success = true;
                    assembly {
                        let length := mload(_preBytes)
                        // if lengths don't match the arrays are not equal
                        switch eq(length, mload(_postBytes))
                        case 1 {
                            // cb is a circuit breaker in the for loop since there's
                            //  no said feature for inline assembly loops
                            // cb = 1 - don't breaker
                            // cb = 0 - break
                            let cb := 1
                            let mc := add(_preBytes, 0x20)
                            let end := add(mc, length)
                            for {
                                let cc := add(_postBytes, 0x20)
                            // the next line is the loop condition:
                            // while(uint(mc < end) + cb == 2)
                            } eq(add(lt(mc, end), cb), 2) {
                                mc := add(mc, 0x20)
                                cc := add(cc, 0x20)
                            } {
                                // if any of these checks fails then arrays are not equal
                                if iszero(eq(mload(mc), mload(cc))) {
                                    // unsuccess:
                                    success := 0
                                    cb := 0
                                }
                            }
                        }
                        default {
                            // unsuccess:
                            success := 0
                        }
                    }
                    return success;
                }
                function equalStorage(bytes storage _preBytes, bytes memory _postBytes) internal view returns (bool) {
                    bool success = true;
                    assembly {
                        // we know _preBytes_offset is 0
                        let fslot := sload(_preBytes_slot)
                        // Decode the length of the stored array like in concatStorage().
                        let slength := div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
                        let mlength := mload(_postBytes)
                        // if lengths don't match the arrays are not equal
                        switch eq(slength, mlength)
                        case 1 {
                            // slength can contain both the length and contents of the array
                            // if length < 32 bytes so let's prepare for that
                            // v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storage
                            if iszero(iszero(slength)) {
                                switch lt(slength, 32)
                                case 1 {
                                    // blank the last byte which is the length
                                    fslot := mul(div(fslot, 0x100), 0x100)
                                    if iszero(eq(fslot, mload(add(_postBytes, 0x20)))) {
                                        // unsuccess:
                                        success := 0
                                    }
                                }
                                default {
                                    // cb is a circuit breaker in the for loop since there's
                                    //  no said feature for inline assembly loops
                                    // cb = 1 - don't breaker
                                    // cb = 0 - break
                                    let cb := 1
                                    // get the keccak hash to get the contents of the array
                                    mstore(0x0, _preBytes_slot)
                                    let sc := keccak256(0x0, 0x20)
                                    let mc := add(_postBytes, 0x20)
                                    let end := add(mc, mlength)
                                    // the next line is the loop condition:
                                    // while(uint(mc < end) + cb == 2)
                                    for {} eq(add(lt(mc, end), cb), 2) {
                                        sc := add(sc, 1)
                                        mc := add(mc, 0x20)
                                    } {
                                        if iszero(eq(sload(sc), mload(mc))) {
                                            // unsuccess:
                                            success := 0
                                            cb := 0
                                        }
                                    }
                                }
                            }
                        }
                        default {
                            // unsuccess:
                            success := 0
                        }
                    }
                    return success;
                }
            }
            // SPDX-FileCopyrightText: 2020 Lido <[email protected]>
            // SPDX-License-Identifier: GPL-3.0
            pragma solidity 0.4.24;
            /**
              * @title Liquid staking pool
              *
              * For the high-level description of the pool operation please refer to the paper.
              * Pool manages withdrawal keys and fees. It receives ether submitted by users on the ETH 1 side
              * and stakes it via the deposit_contract.sol contract. It doesn't hold ether on it's balance,
              * only a small portion (buffer) of it.
              * It also mints new tokens for rewards generated at the ETH 2.0 side.
              *
              * At the moment withdrawals are not possible in the beacon chain and there's no workaround.
              * Pool will be upgraded to an actual implementation when withdrawals are enabled
              * (Phase 1.5 or 2 of Eth2 launch, likely late 2022 or 2023).
              */
            interface ILido {
                function totalSupply() external view returns (uint256);
                function getTotalShares() external view returns (uint256);
                /**
                  * @notice Stop pool routine operations
                  */
                function stop() external;
                /**
                  * @notice Resume pool routine operations
                  */
                function resume() external;
                /**
                  * @notice Stops accepting new Ether to the protocol
                  *
                  * @dev While accepting new Ether is stopped, calls to the `submit` function,
                  * as well as to the default payable function, will revert.
                  *
                  * Emits `StakingPaused` event.
                  */
                function pauseStaking() external;
                /**
                  * @notice Resumes accepting new Ether to the protocol (if `pauseStaking` was called previously)
                  * NB: Staking could be rate-limited by imposing a limit on the stake amount
                  * at each moment in time, see `setStakingLimit()` and `removeStakingLimit()`
                  *
                  * @dev Preserves staking limit if it was set previously
                  *
                  * Emits `StakingResumed` event
                  */
                function resumeStaking() external;
                /**
                  * @notice Sets the staking rate limit
                  *
                  * @dev Reverts if:
                  * - `_maxStakeLimit` == 0
                  * - `_maxStakeLimit` >= 2^96
                  * - `_maxStakeLimit` < `_stakeLimitIncreasePerBlock`
                  * - `_maxStakeLimit` / `_stakeLimitIncreasePerBlock` >= 2^32 (only if `_stakeLimitIncreasePerBlock` != 0)
                  *
                  * Emits `StakingLimitSet` event
                  *
                  * @param _maxStakeLimit max stake limit value
                  * @param _stakeLimitIncreasePerBlock stake limit increase per single block
                  */
                function setStakingLimit(uint256 _maxStakeLimit, uint256 _stakeLimitIncreasePerBlock) external;
                /**
                  * @notice Removes the staking rate limit
                  *
                  * Emits `StakingLimitRemoved` event
                  */
                function removeStakingLimit() external;
                /**
                  * @notice Check staking state: whether it's paused or not
                  */
                function isStakingPaused() external view returns (bool);
                /**
                  * @notice Returns how much Ether can be staked in the current block
                  * @dev Special return values:
                  * - 2^256 - 1 if staking is unlimited;
                  * - 0 if staking is paused or if limit is exhausted.
                  */
                function getCurrentStakeLimit() external view returns (uint256);
                /**
                  * @notice Returns full info about current stake limit params and state
                  * @dev Might be used for the advanced integration requests.
                  * @return isStakingPaused staking pause state (equivalent to return of isStakingPaused())
                  * @return isStakingLimitSet whether the stake limit is set
                  * @return currentStakeLimit current stake limit (equivalent to return of getCurrentStakeLimit())
                  * @return maxStakeLimit max stake limit
                  * @return maxStakeLimitGrowthBlocks blocks needed to restore max stake limit from the fully exhausted state
                  * @return prevStakeLimit previously reached stake limit
                  * @return prevStakeBlockNumber previously seen block number
                  */
                function getStakeLimitFullInfo() external view returns (
                    bool isStakingPaused,
                    bool isStakingLimitSet,
                    uint256 currentStakeLimit,
                    uint256 maxStakeLimit,
                    uint256 maxStakeLimitGrowthBlocks,
                    uint256 prevStakeLimit,
                    uint256 prevStakeBlockNumber
                );
                event Stopped();
                event Resumed();
                event StakingPaused();
                event StakingResumed();
                event StakingLimitSet(uint256 maxStakeLimit, uint256 stakeLimitIncreasePerBlock);
                event StakingLimitRemoved();
                /**
                  * @notice Set Lido protocol contracts (oracle, treasury, insurance fund).
                  * @param _oracle oracle contract
                  * @param _treasury treasury contract
                  * @param _insuranceFund insurance fund contract
                  */
                function setProtocolContracts(
                    address _oracle,
                    address _treasury,
                    address _insuranceFund
                ) external;
                event ProtocolContactsSet(address oracle, address treasury, address insuranceFund);
                /**
                  * @notice Set fee rate to `_feeBasisPoints` basis points.
                  * The fees are accrued when:
                  * - oracles report staking results (beacon chain balance increase)
                  * - validators gain execution layer rewards (priority fees and MEV)
                  * @param _feeBasisPoints Fee rate, in basis points
                  */
                function setFee(uint16 _feeBasisPoints) external;
                /**
                  * @notice Set fee distribution
                  * @param _treasuryFeeBasisPoints basis points go to the treasury,
                  * @param _insuranceFeeBasisPoints basis points go to the insurance fund,
                  * @param _operatorsFeeBasisPoints basis points go to node operators.
                  * @dev The sum has to be 10 000.
                  */
                function setFeeDistribution(
                    uint16 _treasuryFeeBasisPoints,
                    uint16 _insuranceFeeBasisPoints,
                    uint16 _operatorsFeeBasisPoints
                ) external;
                /**
                  * @notice Returns staking rewards fee rate
                  */
                function getFee() external view returns (uint16 feeBasisPoints);
                /**
                  * @notice Returns fee distribution proportion
                  */
                function getFeeDistribution() external view returns (
                    uint16 treasuryFeeBasisPoints,
                    uint16 insuranceFeeBasisPoints,
                    uint16 operatorsFeeBasisPoints
                );
                event FeeSet(uint16 feeBasisPoints);
                event FeeDistributionSet(uint16 treasuryFeeBasisPoints, uint16 insuranceFeeBasisPoints, uint16 operatorsFeeBasisPoints);
                /**
                  * @notice A payable function supposed to be called only by LidoExecutionLayerRewardsVault contract
                  * @dev We need a dedicated function because funds received by the default payable function
                  * are treated as a user deposit
                  */
                function receiveELRewards() external payable;
                // The amount of ETH withdrawn from LidoExecutionLayerRewardsVault contract to Lido contract
                event ELRewardsReceived(uint256 amount);
                /**
                  * @dev Sets limit on amount of ETH to withdraw from execution layer rewards vault per LidoOracle report
                  * @param _limitPoints limit in basis points to amount of ETH to withdraw per LidoOracle report
                  */
                function setELRewardsWithdrawalLimit(uint16 _limitPoints) external;
                // Percent in basis points of total pooled ether allowed to withdraw from LidoExecutionLayerRewardsVault per LidoOracle report
                event ELRewardsWithdrawalLimitSet(uint256 limitPoints);
                /**
                  * @notice Set credentials to withdraw ETH on ETH 2.0 side after the phase 2 is launched to `_withdrawalCredentials`
                  * @dev Note that setWithdrawalCredentials discards all unused signing keys as the signatures are invalidated.
                  * @param _withdrawalCredentials withdrawal credentials field as defined in the Ethereum PoS consensus specs
                  */
                function setWithdrawalCredentials(bytes32 _withdrawalCredentials) external;
                /**
                  * @notice Returns current credentials to withdraw ETH on ETH 2.0 side after the phase 2 is launched
                  */
                function getWithdrawalCredentials() external view returns (bytes);
                event WithdrawalCredentialsSet(bytes32 withdrawalCredentials);
                /**
                  * @dev Sets the address of LidoExecutionLayerRewardsVault contract
                  * @param _executionLayerRewardsVault Execution layer rewards vault contract address
                  */
                function setELRewardsVault(address _executionLayerRewardsVault) external;
                // The `executionLayerRewardsVault` was set as the execution layer rewards vault for Lido
                event ELRewardsVaultSet(address executionLayerRewardsVault);
                /**
                  * @notice Ether on the ETH 2.0 side reported by the oracle
                  * @param _epoch Epoch id
                  * @param _eth2balance Balance in wei on the ETH 2.0 side
                  */
                function handleOracleReport(uint256 _epoch, uint256 _eth2balance) external;
                // User functions
                /**
                  * @notice Adds eth to the pool
                  * @return StETH Amount of StETH generated
                  */
                function submit(address _referral) external payable returns (uint256 StETH);
                // Records a deposit made by a user
                event Submitted(address indexed sender, uint256 amount, address referral);
                // The `amount` of ether was sent to the deposit_contract.deposit function
                event Unbuffered(uint256 amount);
                // Requested withdrawal of `etherAmount` to `pubkeyHash` on the ETH 2.0 side, `tokenAmount` burned by `sender`,
                // `sentFromBuffer` was sent on the current Ethereum side.
                event Withdrawal(address indexed sender, uint256 tokenAmount, uint256 sentFromBuffer,
                                 bytes32 indexed pubkeyHash, uint256 etherAmount);
                // Info functions
                /**
                  * @notice Gets the amount of Ether controlled by the system
                  */
                function getTotalPooledEther() external view returns (uint256);
                /**
                  * @notice Gets the amount of Ether temporary buffered on this contract balance
                  */
                function getBufferedEther() external view returns (uint256);
                /**
                  * @notice Returns the key values related to Beacon-side
                  * @return depositedValidators - number of deposited validators
                  * @return beaconValidators - number of Lido's validators visible in the Beacon state, reported by oracles
                  * @return beaconBalance - total amount of Beacon-side Ether (sum of all the balances of Lido validators)
                  */
                function getBeaconStat() external view returns (uint256 depositedValidators, uint256 beaconValidators, uint256 beaconBalance);
            }
            // SPDX-FileCopyrightText: 2020 Lido <[email protected]>
            // SPDX-License-Identifier: GPL-3.0
            pragma solidity 0.4.24;
            /**
              * @title Node Operator registry
              *
              * Node Operator registry manages signing keys and other node operator data.
              * It's also responsible for distributing rewards to node operators.
              */
            interface INodeOperatorsRegistry {
                /**
                  * @notice Add node operator named `name` with reward address `rewardAddress` and staking limit = 0 validators
                  * @param _name Human-readable name
                  * @param _rewardAddress Ethereum 1 address which receives stETH rewards for this operator
                  * @return a unique key of the added operator
                  */
                function addNodeOperator(string _name, address _rewardAddress) external returns (uint256 id);
                /**
                  * @notice `_active ? 'Enable' : 'Disable'` the node operator #`_id`
                  */
                function setNodeOperatorActive(uint256 _id, bool _active) external;
                /**
                  * @notice Change human-readable name of the node operator #`_id` to `_name`
                  */
                function setNodeOperatorName(uint256 _id, string _name) external;
                /**
                  * @notice Change reward address of the node operator #`_id` to `_rewardAddress`
                  */
                function setNodeOperatorRewardAddress(uint256 _id, address _rewardAddress) external;
                /**
                  * @notice Set the maximum number of validators to stake for the node operator #`_id` to `_stakingLimit`
                  */
                function setNodeOperatorStakingLimit(uint256 _id, uint64 _stakingLimit) external;
                /**
                  * @notice Report `_stoppedIncrement` more stopped validators of the node operator #`_id`
                  */
                function reportStoppedValidators(uint256 _id, uint64 _stoppedIncrement) external;
                /**
                  * @notice Remove unused signing keys
                  * @dev Function is used by the pool
                  */
                function trimUnusedKeys() external;
                /**
                  * @notice Returns total number of node operators
                  */
                function getNodeOperatorsCount() external view returns (uint256);
                /**
                  * @notice Returns number of active node operators
                  */
                function getActiveNodeOperatorsCount() external view returns (uint256);
                /**
                  * @notice Returns the n-th node operator
                  * @param _id Node Operator id
                  * @param _fullInfo If true, name will be returned as well
                  */
                function getNodeOperator(uint256 _id, bool _fullInfo) external view returns (
                    bool active,
                    string name,
                    address rewardAddress,
                    uint64 stakingLimit,
                    uint64 stoppedValidators,
                    uint64 totalSigningKeys,
                    uint64 usedSigningKeys);
                /**
                  * @notice Returns the rewards distribution proportional to the effective stake for each node operator.
                  * @param _totalRewardShares Total amount of reward shares to distribute.
                  */
                function getRewardsDistribution(uint256 _totalRewardShares) external view returns (
                    address[] memory recipients,
                    uint256[] memory shares
                );
                event NodeOperatorAdded(uint256 id, string name, address rewardAddress, uint64 stakingLimit);
                event NodeOperatorActiveSet(uint256 indexed id, bool active);
                event NodeOperatorNameSet(uint256 indexed id, string name);
                event NodeOperatorRewardAddressSet(uint256 indexed id, address rewardAddress);
                event NodeOperatorStakingLimitSet(uint256 indexed id, uint64 stakingLimit);
                event NodeOperatorTotalStoppedValidatorsReported(uint256 indexed id, uint64 totalStopped);
                event NodeOperatorTotalKeysTrimmed(uint256 indexed id, uint64 totalKeysTrimmed);
                /**
                 * @notice Selects and returns at most `_numKeys` signing keys (as well as the corresponding
                 *         signatures) from the set of active keys and marks the selected keys as used.
                 *         May only be called by the pool contract.
                 *
                 * @param _numKeys The number of keys to select. The actual number of selected keys may be less
                 *        due to the lack of active keys.
                 */
                function assignNextSigningKeys(uint256 _numKeys) external returns (bytes memory pubkeys, bytes memory signatures);
                /**
                  * @notice Add `_quantity` validator signing keys to the keys of the node operator #`_operator_id`. Concatenated keys are: `_pubkeys`
                  * @dev Along with each key the DAO has to provide a signatures for the
                  *      (pubkey, withdrawal_credentials, 32000000000) message.
                  *      Given that information, the contract'll be able to call
                  *      deposit_contract.deposit on-chain.
                  * @param _operator_id Node Operator id
                  * @param _quantity Number of signing keys provided
                  * @param _pubkeys Several concatenated validator signing keys
                  * @param _signatures Several concatenated signatures for (pubkey, withdrawal_credentials, 32000000000) messages
                  */
                function addSigningKeys(uint256 _operator_id, uint256 _quantity, bytes _pubkeys, bytes _signatures) external;
                /**
                  * @notice Add `_quantity` validator signing keys of operator #`_id` to the set of usable keys. Concatenated keys are: `_pubkeys`. Can be done by node operator in question by using the designated rewards address.
                  * @dev Along with each key the DAO has to provide a signatures for the
                  *      (pubkey, withdrawal_credentials, 32000000000) message.
                  *      Given that information, the contract'll be able to call
                  *      deposit_contract.deposit on-chain.
                  * @param _operator_id Node Operator id
                  * @param _quantity Number of signing keys provided
                  * @param _pubkeys Several concatenated validator signing keys
                  * @param _signatures Several concatenated signatures for (pubkey, withdrawal_credentials, 32000000000) messages
                  */
                function addSigningKeysOperatorBH(uint256 _operator_id, uint256 _quantity, bytes _pubkeys, bytes _signatures) external;
                /**
                  * @notice Removes a validator signing key #`_index` from the keys of the node operator #`_operator_id`
                  * @param _operator_id Node Operator id
                  * @param _index Index of the key, starting with 0
                  */
                function removeSigningKey(uint256 _operator_id, uint256 _index) external;
                /**
                  * @notice Removes a validator signing key #`_index` of operator #`_id` from the set of usable keys. Executed on behalf of Node Operator.
                  * @param _operator_id Node Operator id
                  * @param _index Index of the key, starting with 0
                  */
                function removeSigningKeyOperatorBH(uint256 _operator_id, uint256 _index) external;
                /**
                  * @notice Removes an #`_amount` of validator signing keys starting from #`_index` of operator #`_id` usable keys. Executed on behalf of DAO.
                  * @param _operator_id Node Operator id
                  * @param _index Index of the key, starting with 0
                  * @param _amount Number of keys to remove
                  */
                function removeSigningKeys(uint256 _operator_id, uint256 _index, uint256 _amount) external;
                /**
                  * @notice Removes an #`_amount` of validator signing keys starting from #`_index` of operator #`_id` usable keys. Executed on behalf of Node Operator.
                  * @param _operator_id Node Operator id
                  * @param _index Index of the key, starting with 0
                  * @param _amount Number of keys to remove
                  */
                function removeSigningKeysOperatorBH(uint256 _operator_id, uint256 _index, uint256 _amount) external;
                /**
                  * @notice Returns total number of signing keys of the node operator #`_operator_id`
                  */
                function getTotalSigningKeyCount(uint256 _operator_id) external view returns (uint256);
                /**
                  * @notice Returns number of usable signing keys of the node operator #`_operator_id`
                  */
                function getUnusedSigningKeyCount(uint256 _operator_id) external view returns (uint256);
                /**
                  * @notice Returns n-th signing key of the node operator #`_operator_id`
                  * @param _operator_id Node Operator id
                  * @param _index Index of the key, starting with 0
                  * @return key Key
                  * @return depositSignature Signature needed for a deposit_contract.deposit call
                  * @return used Flag indication if the key was used in the staking
                  */
                function getSigningKey(uint256 _operator_id, uint256 _index) external view returns
                        (bytes key, bytes depositSignature, bool used);
                /**
                 * @notice Returns a monotonically increasing counter that gets incremented when any of the following happens:
                 *   1. a node operator's key(s) is added;
                 *   2. a node operator's key(s) is removed;
                 *   3. a node operator's approved keys limit is changed.
                 *   4. a node operator was activated/deactivated. Activation or deactivation of node operator
                 *      might lead to usage of unvalidated keys in the assignNextSigningKeys method.
                 */
                function getKeysOpIndex() external view returns (uint256);
                event SigningKeyAdded(uint256 indexed operatorId, bytes pubkey);
                event SigningKeyRemoved(uint256 indexed operatorId, bytes pubkey);
                event KeysOpIndexSet(uint256 keysOpIndex);
            }
            // SPDX-FileCopyrightText: 2020 Lido <[email protected]>
            // SPDX-License-Identifier: GPL-3.0
            pragma solidity 0.4.24;
            /**
              * @title Deposit contract interface
              */
            interface IDepositContract {
                /**
                  * @notice Top-ups deposit of a validator on the ETH 2.0 side
                  * @param pubkey Validator signing key
                  * @param withdrawal_credentials Credentials that allows to withdraw funds
                  * @param signature Signature of the request
                  * @param deposit_data_root The deposits Merkle tree node, used as a checksum
                  */
                function deposit(
                    bytes /* 48 */ pubkey,
                    bytes /* 32 */ withdrawal_credentials,
                    bytes /* 96 */ signature,
                    bytes32 deposit_data_root
                )
                    external payable;
            }
            // SPDX-FileCopyrightText: 2021 Lido <[email protected]>
            // SPDX-License-Identifier: GPL-3.0
            pragma solidity 0.4.24;
            interface ILidoExecutionLayerRewardsVault {
                /**
                * @notice Withdraw all accumulated execution layer rewards to Lido contract
                * @param _maxAmount Max amount of ETH to withdraw
                * @return amount of funds received as execution layer rewards (in wei)
                */
                function withdrawRewards(uint256 _maxAmount) external returns (uint256 amount);
            }
            // SPDX-FileCopyrightText: 2020 Lido <[email protected]>
            // SPDX-License-Identifier: GPL-3.0
            /* See contracts/COMPILERS.md */
            pragma solidity 0.4.24;
            import "openzeppelin-solidity/contracts/token/ERC20/IERC20.sol";
            import "@aragon/os/contracts/common/UnstructuredStorage.sol";
            import "@aragon/os/contracts/lib/math/SafeMath.sol";
            import "./lib/Pausable.sol";
            /**
             * @title Interest-bearing ERC20-like token for Lido Liquid Stacking protocol.
             *
             * This contract is abstract. To make the contract deployable override the
             * `_getTotalPooledEther` function. `Lido.sol` contract inherits StETH and defines
             * the `_getTotalPooledEther` function.
             *
             * StETH balances are dynamic and represent the holder's share in the total amount
             * of Ether controlled by the protocol. Account shares aren't normalized, so the
             * contract also stores the sum of all shares to calculate each account's token balance
             * which equals to:
             *
             *   shares[account] * _getTotalPooledEther() / _getTotalShares()
             *
             * For example, assume that we have:
             *
             *   _getTotalPooledEther() -> 10 ETH
             *   sharesOf(user1) -> 100
             *   sharesOf(user2) -> 400
             *
             * Therefore:
             *
             *   balanceOf(user1) -> 2 tokens which corresponds 2 ETH
             *   balanceOf(user2) -> 8 tokens which corresponds 8 ETH
             *
             * Since balances of all token holders change when the amount of total pooled Ether
             * changes, this token cannot fully implement ERC20 standard: it only emits `Transfer`
             * events upon explicit transfer between holders. In contrast, when total amount of
             * pooled Ether increases, no `Transfer` events are generated: doing so would require
             * emitting an event for each token holder and thus running an unbounded loop.
             *
             * The token inherits from `Pausable` and uses `whenNotStopped` modifier for methods
             * which change `shares` or `allowances`. `_stop` and `_resume` functions are overridden
             * in `Lido.sol` and might be called by an account with the `PAUSE_ROLE` assigned by the
             * DAO. This is useful for emergency scenarios, e.g. a protocol bug, where one might want
             * to freeze all token transfers and approvals until the emergency is resolved.
             */
            contract StETH is IERC20, Pausable {
                using SafeMath for uint256;
                using UnstructuredStorage for bytes32;
                /**
                 * @dev StETH balances are dynamic and are calculated based on the accounts' shares
                 * and the total amount of Ether controlled by the protocol. Account shares aren't
                 * normalized, so the contract also stores the sum of all shares to calculate
                 * each account's token balance which equals to:
                 *
                 *   shares[account] * _getTotalPooledEther() / _getTotalShares()
                */
                mapping (address => uint256) private shares;
                /**
                 * @dev Allowances are nominated in tokens, not token shares.
                 */
                mapping (address => mapping (address => uint256)) private allowances;
                /**
                 * @dev Storage position used for holding the total amount of shares in existence.
                 *
                 * The Lido protocol is built on top of Aragon and uses the Unstructured Storage pattern
                 * for value types:
                 *
                 * https://blog.openzeppelin.com/upgradeability-using-unstructured-storage
                 * https://blog.8bitzen.com/posts/20-02-2020-understanding-how-solidity-upgradeable-unstructured-proxies-work
                 *
                 * For reference types, conventional storage variables are used since it's non-trivial
                 * and error-prone to implement reference-type unstructured storage using Solidity v0.4;
                 * see https://github.com/lidofinance/lido-dao/issues/181#issuecomment-736098834
                 */
                bytes32 internal constant TOTAL_SHARES_POSITION = keccak256("lido.StETH.totalShares");
                /**
                  * @notice An executed shares transfer from `sender` to `recipient`.
                  *
                  * @dev emitted in pair with an ERC20-defined `Transfer` event.
                  */
                event TransferShares(
                    address indexed from,
                    address indexed to,
                    uint256 sharesValue
                );
                /**
                 * @notice An executed `burnShares` request
                 *
                 * @dev Reports simultaneously burnt shares amount
                 * and corresponding stETH amount.
                 * The stETH amount is calculated twice: before and after the burning incurred rebase.
                 *
                 * @param account holder of the burnt shares
                 * @param preRebaseTokenAmount amount of stETH the burnt shares corresponded to before the burn
                 * @param postRebaseTokenAmount amount of stETH the burnt shares corresponded to after the burn
                 * @param sharesAmount amount of burnt shares
                 */
                event SharesBurnt(
                    address indexed account,
                    uint256 preRebaseTokenAmount,
                    uint256 postRebaseTokenAmount,
                    uint256 sharesAmount
                );
                /**
                 * @return the name of the token.
                 */
                function name() public pure returns (string) {
                    return "Liquid staked Ether 2.0";
                }
                /**
                 * @return the symbol of the token, usually a shorter version of the
                 * name.
                 */
                function symbol() public pure returns (string) {
                    return "stETH";
                }
                /**
                 * @return the number of decimals for getting user representation of a token amount.
                 */
                function decimals() public pure returns (uint8) {
                    return 18;
                }
                /**
                 * @return the amount of tokens in existence.
                 *
                 * @dev Always equals to `_getTotalPooledEther()` since token amount
                 * is pegged to the total amount of Ether controlled by the protocol.
                 */
                function totalSupply() public view returns (uint256) {
                    return _getTotalPooledEther();
                }
                /**
                 * @return the entire amount of Ether controlled by the protocol.
                 *
                 * @dev The sum of all ETH balances in the protocol, equals to the total supply of stETH.
                 */
                function getTotalPooledEther() public view returns (uint256) {
                    return _getTotalPooledEther();
                }
                /**
                 * @return the amount of tokens owned by the `_account`.
                 *
                 * @dev Balances are dynamic and equal the `_account`'s share in the amount of the
                 * total Ether controlled by the protocol. See `sharesOf`.
                 */
                function balanceOf(address _account) public view returns (uint256) {
                    return getPooledEthByShares(_sharesOf(_account));
                }
                /**
                 * @notice Moves `_amount` tokens from the caller's account to the `_recipient` account.
                 *
                 * @return a boolean value indicating whether the operation succeeded.
                 * Emits a `Transfer` event.
                 * Emits a `TransferShares` event.
                 *
                 * Requirements:
                 *
                 * - `_recipient` cannot be the zero address.
                 * - the caller must have a balance of at least `_amount`.
                 * - the contract must not be paused.
                 *
                 * @dev The `_amount` argument is the amount of tokens, not shares.
                 */
                function transfer(address _recipient, uint256 _amount) public returns (bool) {
                    _transfer(msg.sender, _recipient, _amount);
                    return true;
                }
                /**
                 * @return the remaining number of tokens that `_spender` is allowed to spend
                 * on behalf of `_owner` through `transferFrom`. This is zero by default.
                 *
                 * @dev This value changes when `approve` or `transferFrom` is called.
                 */
                function allowance(address _owner, address _spender) public view returns (uint256) {
                    return allowances[_owner][_spender];
                }
                /**
                 * @notice Sets `_amount` as the allowance of `_spender` over the caller's tokens.
                 *
                 * @return a boolean value indicating whether the operation succeeded.
                 * Emits an `Approval` event.
                 *
                 * Requirements:
                 *
                 * - `_spender` cannot be the zero address.
                 * - the contract must not be paused.
                 *
                 * @dev The `_amount` argument is the amount of tokens, not shares.
                 */
                function approve(address _spender, uint256 _amount) public returns (bool) {
                    _approve(msg.sender, _spender, _amount);
                    return true;
                }
                /**
                 * @notice Moves `_amount` tokens from `_sender` to `_recipient` using the
                 * allowance mechanism. `_amount` is then deducted from the caller's
                 * allowance.
                 *
                 * @return a boolean value indicating whether the operation succeeded.
                 *
                 * Emits a `Transfer` event.
                 * Emits a `TransferShares` event.
                 * Emits an `Approval` event indicating the updated allowance.
                 *
                 * Requirements:
                 *
                 * - `_sender` and `_recipient` cannot be the zero addresses.
                 * - `_sender` must have a balance of at least `_amount`.
                 * - the caller must have allowance for `_sender`'s tokens of at least `_amount`.
                 * - the contract must not be paused.
                 *
                 * @dev The `_amount` argument is the amount of tokens, not shares.
                 */
                function transferFrom(address _sender, address _recipient, uint256 _amount) public returns (bool) {
                    uint256 currentAllowance = allowances[_sender][msg.sender];
                    require(currentAllowance >= _amount, "TRANSFER_AMOUNT_EXCEEDS_ALLOWANCE");
                    _transfer(_sender, _recipient, _amount);
                    _approve(_sender, msg.sender, currentAllowance.sub(_amount));
                    return true;
                }
                /**
                 * @notice Atomically increases the allowance granted to `_spender` by the caller by `_addedValue`.
                 *
                 * This is an alternative to `approve` that can be used as a mitigation for
                 * problems described in:
                 * https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/IERC20.sol#L42
                 * Emits an `Approval` event indicating the updated allowance.
                 *
                 * Requirements:
                 *
                 * - `_spender` cannot be the the zero address.
                 * - the contract must not be paused.
                 */
                function increaseAllowance(address _spender, uint256 _addedValue) public returns (bool) {
                    _approve(msg.sender, _spender, allowances[msg.sender][_spender].add(_addedValue));
                    return true;
                }
                /**
                 * @notice Atomically decreases the allowance granted to `_spender` by the caller by `_subtractedValue`.
                 *
                 * This is an alternative to `approve` that can be used as a mitigation for
                 * problems described in:
                 * https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/IERC20.sol#L42
                 * 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`.
                 * - the contract must not be paused.
                 */
                function decreaseAllowance(address _spender, uint256 _subtractedValue) public returns (bool) {
                    uint256 currentAllowance = allowances[msg.sender][_spender];
                    require(currentAllowance >= _subtractedValue, "DECREASED_ALLOWANCE_BELOW_ZERO");
                    _approve(msg.sender, _spender, currentAllowance.sub(_subtractedValue));
                    return true;
                }
                /**
                 * @return the total amount of shares in existence.
                 *
                 * @dev The sum of all accounts' shares can be an arbitrary number, therefore
                 * it is necessary to store it in order to calculate each account's relative share.
                 */
                function getTotalShares() public view returns (uint256) {
                    return _getTotalShares();
                }
                /**
                 * @return the amount of shares owned by `_account`.
                 */
                function sharesOf(address _account) public view returns (uint256) {
                    return _sharesOf(_account);
                }
                /**
                 * @return the amount of shares that corresponds to `_ethAmount` protocol-controlled Ether.
                 */
                function getSharesByPooledEth(uint256 _ethAmount) public view returns (uint256) {
                    uint256 totalPooledEther = _getTotalPooledEther();
                    if (totalPooledEther == 0) {
                        return 0;
                    } else {
                        return _ethAmount
                            .mul(_getTotalShares())
                            .div(totalPooledEther);
                    }
                }
                /**
                 * @return the amount of Ether that corresponds to `_sharesAmount` token shares.
                 */
                function getPooledEthByShares(uint256 _sharesAmount) public view returns (uint256) {
                    uint256 totalShares = _getTotalShares();
                    if (totalShares == 0) {
                        return 0;
                    } else {
                        return _sharesAmount
                            .mul(_getTotalPooledEther())
                            .div(totalShares);
                    }
                }
                /**
                 * @notice Moves `_sharesAmount` token shares from the caller's account to the `_recipient` account.
                 *
                 * @return amount of transferred tokens.
                 * Emits a `TransferShares` event.
                 * Emits a `Transfer` event.
                 *
                 * Requirements:
                 *
                 * - `_recipient` cannot be the zero address.
                 * - the caller must have at least `_sharesAmount` shares.
                 * - the contract must not be paused.
                 *
                 * @dev The `_sharesAmount` argument is the amount of shares, not tokens.
                 */
                function transferShares(address _recipient, uint256 _sharesAmount) public returns (uint256) {
                    _transferShares(msg.sender, _recipient, _sharesAmount);
                    emit TransferShares(msg.sender, _recipient, _sharesAmount);
                    uint256 tokensAmount = getPooledEthByShares(_sharesAmount);
                    emit Transfer(msg.sender, _recipient, tokensAmount);
                    return tokensAmount;
                }
                /**
                 * @return the total amount (in wei) of Ether controlled by the protocol.
                 * @dev This is used for calculating tokens from shares and vice versa.
                 * @dev This function is required to be implemented in a derived contract.
                 */
                function _getTotalPooledEther() internal view returns (uint256);
                /**
                 * @notice Moves `_amount` tokens from `_sender` to `_recipient`.
                 * Emits a `Transfer` event.
                 * Emits a `TransferShares` event.
                 */
                function _transfer(address _sender, address _recipient, uint256 _amount) internal {
                    uint256 _sharesToTransfer = getSharesByPooledEth(_amount);
                    _transferShares(_sender, _recipient, _sharesToTransfer);
                    emit Transfer(_sender, _recipient, _amount);
                    emit TransferShares(_sender, _recipient, _sharesToTransfer);
                }
                /**
                 * @notice Sets `_amount` as the allowance of `_spender` over the `_owner` s tokens.
                 *
                 * Emits an `Approval` event.
                 *
                 * Requirements:
                 *
                 * - `_owner` cannot be the zero address.
                 * - `_spender` cannot be the zero address.
                 * - the contract must not be paused.
                 */
                function _approve(address _owner, address _spender, uint256 _amount) internal whenNotStopped {
                    require(_owner != address(0), "APPROVE_FROM_ZERO_ADDRESS");
                    require(_spender != address(0), "APPROVE_TO_ZERO_ADDRESS");
                    allowances[_owner][_spender] = _amount;
                    emit Approval(_owner, _spender, _amount);
                }
                /**
                 * @return the total amount of shares in existence.
                 */
                function _getTotalShares() internal view returns (uint256) {
                    return TOTAL_SHARES_POSITION.getStorageUint256();
                }
                /**
                 * @return the amount of shares owned by `_account`.
                 */
                function _sharesOf(address _account) internal view returns (uint256) {
                    return shares[_account];
                }
                /**
                 * @notice Moves `_sharesAmount` shares from `_sender` to `_recipient`.
                 *
                 * Requirements:
                 *
                 * - `_sender` cannot be the zero address.
                 * - `_recipient` cannot be the zero address.
                 * - `_sender` must hold at least `_sharesAmount` shares.
                 * - the contract must not be paused.
                 */
                function _transferShares(address _sender, address _recipient, uint256 _sharesAmount) internal whenNotStopped {
                    require(_sender != address(0), "TRANSFER_FROM_THE_ZERO_ADDRESS");
                    require(_recipient != address(0), "TRANSFER_TO_THE_ZERO_ADDRESS");
                    uint256 currentSenderShares = shares[_sender];
                    require(_sharesAmount <= currentSenderShares, "TRANSFER_AMOUNT_EXCEEDS_BALANCE");
                    shares[_sender] = currentSenderShares.sub(_sharesAmount);
                    shares[_recipient] = shares[_recipient].add(_sharesAmount);
                }
                /**
                 * @notice Creates `_sharesAmount` shares and assigns them to `_recipient`, increasing the total amount of shares.
                 * @dev This doesn't increase the token total supply.
                 *
                 * Requirements:
                 *
                 * - `_recipient` cannot be the zero address.
                 * - the contract must not be paused.
                 */
                function _mintShares(address _recipient, uint256 _sharesAmount) internal whenNotStopped returns (uint256 newTotalShares) {
                    require(_recipient != address(0), "MINT_TO_THE_ZERO_ADDRESS");
                    newTotalShares = _getTotalShares().add(_sharesAmount);
                    TOTAL_SHARES_POSITION.setStorageUint256(newTotalShares);
                    shares[_recipient] = shares[_recipient].add(_sharesAmount);
                    // Notice: we're not emitting a Transfer event from the zero address here since shares mint
                    // works by taking the amount of tokens corresponding to the minted shares from all other
                    // token holders, proportionally to their share. The total supply of the token doesn't change
                    // as the result. This is equivalent to performing a send from each other token holder's
                    // address to `address`, but we cannot reflect this as it would require sending an unbounded
                    // number of events.
                }
                /**
                 * @notice Destroys `_sharesAmount` shares from `_account`'s holdings, decreasing the total amount of shares.
                 * @dev This doesn't decrease the token total supply.
                 *
                 * Requirements:
                 *
                 * - `_account` cannot be the zero address.
                 * - `_account` must hold at least `_sharesAmount` shares.
                 * - the contract must not be paused.
                 */
                function _burnShares(address _account, uint256 _sharesAmount) internal whenNotStopped returns (uint256 newTotalShares) {
                    require(_account != address(0), "BURN_FROM_THE_ZERO_ADDRESS");
                    uint256 accountShares = shares[_account];
                    require(_sharesAmount <= accountShares, "BURN_AMOUNT_EXCEEDS_BALANCE");
                    uint256 preRebaseTokenAmount = getPooledEthByShares(_sharesAmount);
                    newTotalShares = _getTotalShares().sub(_sharesAmount);
                    TOTAL_SHARES_POSITION.setStorageUint256(newTotalShares);
                    shares[_account] = accountShares.sub(_sharesAmount);
                    uint256 postRebaseTokenAmount = getPooledEthByShares(_sharesAmount);
                    emit SharesBurnt(_account, preRebaseTokenAmount, postRebaseTokenAmount, _sharesAmount);
                    // Notice: we're not emitting a Transfer event to the zero address here since shares burn
                    // works by redistributing the amount of tokens corresponding to the burned shares between
                    // all other token holders. The total supply of the token doesn't change as the result.
                    // This is equivalent to performing a send from `address` to each other token holder address,
                    // but we cannot reflect this as it would require sending an unbounded number of events.
                    // We're emitting `SharesBurnt` event to provide an explicit rebase log record nonetheless.
                }
            }
            // SPDX-FileCopyrightText: 2022 Lido <[email protected]>
            // SPDX-License-Identifier: GPL-3.0
            /* See contracts/COMPILERS.md */
            pragma solidity 0.4.24;
            import "@aragon/os/contracts/common/UnstructuredStorage.sol";
            //
            // We need to pack four variables into the same 256bit-wide storage slot
            // to lower the costs per each staking request.
            //
            // As a result, slot's memory aligned as follows:
            //
            // MSB ------------------------------------------------------------------------------> LSB
            // 256____________160_________________________128_______________32_____________________ 0
            // |_______________|___________________________|________________|_______________________|
            // | maxStakeLimit | maxStakeLimitGrowthBlocks | prevStakeLimit | prevStakeBlockNumber  |
            // |<-- 96 bits -->|<---------- 32 bits ------>|<-- 96 bits --->|<----- 32 bits ------->|
            //
            //
            // NB: Internal representation conventions:
            //
            // - the `maxStakeLimitGrowthBlocks` field above represented as follows:
            // `maxStakeLimitGrowthBlocks` = `maxStakeLimit` / `stakeLimitIncreasePerBlock`
            //           32 bits                 96 bits               96 bits
            //
            //
            // - the "staking paused" state is encoded by `prevStakeBlockNumber` being zero,
            // - the "staking unlimited" state is encoded by `maxStakeLimit` being zero and `prevStakeBlockNumber` being non-zero.
            //
            /**
            * @notice Library for the internal structs definitions
            * @dev solidity <0.6 doesn't support top-level structs
            * using the library to have a proper namespace
            */
            library StakeLimitState {
                /**
                  * @dev Internal representation struct (slot-wide)
                  */
                struct Data {
                    uint32 prevStakeBlockNumber;
                    uint96 prevStakeLimit;
                    uint32 maxStakeLimitGrowthBlocks;
                    uint96 maxStakeLimit;
                }
            }
            library StakeLimitUnstructuredStorage {
                using UnstructuredStorage for bytes32;
                /// @dev Storage offset for `maxStakeLimit` (bits)
                uint256 internal constant MAX_STAKE_LIMIT_OFFSET = 160;
                /// @dev Storage offset for `maxStakeLimitGrowthBlocks` (bits)
                uint256 internal constant MAX_STAKE_LIMIT_GROWTH_BLOCKS_OFFSET = 128;
                /// @dev Storage offset for `prevStakeLimit` (bits)
                uint256 internal constant PREV_STAKE_LIMIT_OFFSET = 32;
                /// @dev Storage offset for `prevStakeBlockNumber` (bits)
                uint256 internal constant PREV_STAKE_BLOCK_NUMBER_OFFSET = 0;
                /**
                * @dev Read stake limit state from the unstructured storage position
                * @param _position storage offset
                */
                function getStorageStakeLimitStruct(bytes32 _position) internal view returns (StakeLimitState.Data memory stakeLimit) {
                    uint256 slotValue = _position.getStorageUint256();
                    stakeLimit.prevStakeBlockNumber = uint32(slotValue >> PREV_STAKE_BLOCK_NUMBER_OFFSET);
                    stakeLimit.prevStakeLimit = uint96(slotValue >> PREV_STAKE_LIMIT_OFFSET);
                    stakeLimit.maxStakeLimitGrowthBlocks = uint32(slotValue >> MAX_STAKE_LIMIT_GROWTH_BLOCKS_OFFSET);
                    stakeLimit.maxStakeLimit = uint96(slotValue >> MAX_STAKE_LIMIT_OFFSET);
                }
                 /**
                * @dev Write stake limit state to the unstructured storage position
                * @param _position storage offset
                * @param _data stake limit state structure instance
                */
                function setStorageStakeLimitStruct(bytes32 _position, StakeLimitState.Data memory _data) internal {
                    _position.setStorageUint256(
                        uint256(_data.prevStakeBlockNumber) << PREV_STAKE_BLOCK_NUMBER_OFFSET
                            | uint256(_data.prevStakeLimit) << PREV_STAKE_LIMIT_OFFSET
                            | uint256(_data.maxStakeLimitGrowthBlocks) << MAX_STAKE_LIMIT_GROWTH_BLOCKS_OFFSET
                            | uint256(_data.maxStakeLimit) << MAX_STAKE_LIMIT_OFFSET
                    );
                }
            }
            /**
            * @notice Interface library with helper functions to deal with stake limit struct in a more high-level approach.
            */
            library StakeLimitUtils {
                /**
                * @notice Calculate stake limit for the current block.
                */
                function calculateCurrentStakeLimit(StakeLimitState.Data memory _data) internal view returns(uint256 limit) {
                    uint256 stakeLimitIncPerBlock;
                    if (_data.maxStakeLimitGrowthBlocks != 0) {
                        stakeLimitIncPerBlock = _data.maxStakeLimit / _data.maxStakeLimitGrowthBlocks;
                    }
                    limit = _data.prevStakeLimit + ((block.number - _data.prevStakeBlockNumber) * stakeLimitIncPerBlock);
                    if (limit > _data.maxStakeLimit) {
                        limit = _data.maxStakeLimit;
                    }
                }
                /**
                * @notice check if staking is on pause
                */
                function isStakingPaused(StakeLimitState.Data memory _data) internal pure returns(bool) {
                    return _data.prevStakeBlockNumber == 0;
                }
                /**
                * @notice check if staking limit is set (otherwise staking is unlimited)
                */
                function isStakingLimitSet(StakeLimitState.Data memory _data) internal pure returns(bool) {
                    return _data.maxStakeLimit != 0;
                }
                /**
                * @notice update stake limit repr with the desired limits
                * @dev input `_data` param is mutated and the func returns effectively the same pointer
                * @param _data stake limit state struct
                * @param _maxStakeLimit stake limit max value
                * @param _stakeLimitIncreasePerBlock stake limit increase (restoration) per block
                */
                function setStakingLimit(
                    StakeLimitState.Data memory _data,
                    uint256 _maxStakeLimit,
                    uint256 _stakeLimitIncreasePerBlock
                ) internal view returns (StakeLimitState.Data memory) {
                    require(_maxStakeLimit != 0, "ZERO_MAX_STAKE_LIMIT");
                    require(_maxStakeLimit <= uint96(-1), "TOO_LARGE_MAX_STAKE_LIMIT");
                    require(_maxStakeLimit >= _stakeLimitIncreasePerBlock, "TOO_LARGE_LIMIT_INCREASE");
                    require(
                        (_stakeLimitIncreasePerBlock == 0)
                        || (_maxStakeLimit / _stakeLimitIncreasePerBlock <= uint32(-1)),
                        "TOO_SMALL_LIMIT_INCREASE"
                    );
                    // if staking was paused or unlimited previously,
                    // or new limit is lower than previous, then
                    // reset prev stake limit to the new max stake limit
                    if ((_data.maxStakeLimit == 0) || (_maxStakeLimit < _data.prevStakeLimit)) {
                        _data.prevStakeLimit = uint96(_maxStakeLimit);
                    }
                    _data.maxStakeLimitGrowthBlocks = _stakeLimitIncreasePerBlock != 0 ? uint32(_maxStakeLimit / _stakeLimitIncreasePerBlock) : 0;
                    _data.maxStakeLimit = uint96(_maxStakeLimit);
                    if (_data.prevStakeBlockNumber != 0) {
                        _data.prevStakeBlockNumber = uint32(block.number);
                    }
                    return _data;
                }
                /**
                * @notice update stake limit repr to remove the limit
                * @dev input `_data` param is mutated and the func returns effectively the same pointer
                * @param _data stake limit state struct
                */
                function removeStakingLimit(
                    StakeLimitState.Data memory _data
                ) internal view returns (StakeLimitState.Data memory) {
                    _data.maxStakeLimit = 0;
                    return _data;
                }
                /**
                * @notice update stake limit repr after submitting user's eth
                * @dev input `_data` param is mutated and the func returns effectively the same pointer
                * @param _data stake limit state struct
                * @param _newPrevStakeLimit new value for the `prevStakeLimit` field
                */
                function updatePrevStakeLimit(
                    StakeLimitState.Data memory _data,
                    uint256 _newPrevStakeLimit
                ) internal view returns (StakeLimitState.Data memory) {
                    assert(_newPrevStakeLimit <= uint96(-1));
                    assert(_data.prevStakeBlockNumber != 0);
                    _data.prevStakeLimit = uint96(_newPrevStakeLimit);
                    _data.prevStakeBlockNumber = uint32(block.number);
                    return _data;
                }
                /**
                * @notice set stake limit pause state (on or off)
                * @dev input `_data` param is mutated and the func returns effectively the same pointer
                * @param _data stake limit state struct
                * @param _isPaused pause state flag
                */
                function setStakeLimitPauseState(
                    StakeLimitState.Data memory _data,
                    bool _isPaused
                ) internal view returns (StakeLimitState.Data memory) {
                    _data.prevStakeBlockNumber = uint32(_isPaused ? 0 : block.number);
                    return _data;
                }
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            import "../common/UnstructuredStorage.sol";
            import "../kernel/IKernel.sol";
            contract AppStorage {
                using UnstructuredStorage for bytes32;
                /* Hardcoded constants to save gas
                bytes32 internal constant KERNEL_POSITION = keccak256("aragonOS.appStorage.kernel");
                bytes32 internal constant APP_ID_POSITION = keccak256("aragonOS.appStorage.appId");
                */
                bytes32 internal constant KERNEL_POSITION = 0x4172f0f7d2289153072b0a6ca36959e0cbe2efc3afe50fc81636caa96338137b;
                bytes32 internal constant APP_ID_POSITION = 0xd625496217aa6a3453eecb9c3489dc5a53e6c67b444329ea2b2cbc9ff547639b;
                function kernel() public view returns (IKernel) {
                    return IKernel(KERNEL_POSITION.getStorageAddress());
                }
                function appId() public view returns (bytes32) {
                    return APP_ID_POSITION.getStorageBytes32();
                }
                function setKernel(IKernel _kernel) internal {
                    KERNEL_POSITION.setStorageAddress(address(_kernel));
                }
                function setAppId(bytes32 _appId) internal {
                    APP_ID_POSITION.setStorageBytes32(_appId);
                }
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            contract ACLSyntaxSugar {
                function arr() internal pure returns (uint256[]) {
                    return new uint256[](0);
                }
                function arr(bytes32 _a) internal pure returns (uint256[] r) {
                    return arr(uint256(_a));
                }
                function arr(bytes32 _a, bytes32 _b) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b));
                }
                function arr(address _a) internal pure returns (uint256[] r) {
                    return arr(uint256(_a));
                }
                function arr(address _a, address _b) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b));
                }
                function arr(address _a, uint256 _b, uint256 _c) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), _b, _c);
                }
                function arr(address _a, uint256 _b, uint256 _c, uint256 _d) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), _b, _c, _d);
                }
                function arr(address _a, uint256 _b) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b));
                }
                function arr(address _a, address _b, uint256 _c, uint256 _d, uint256 _e) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b), _c, _d, _e);
                }
                function arr(address _a, address _b, address _c) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b), uint256(_c));
                }
                function arr(address _a, address _b, uint256 _c) internal pure returns (uint256[] r) {
                    return arr(uint256(_a), uint256(_b), uint256(_c));
                }
                function arr(uint256 _a) internal pure returns (uint256[] r) {
                    r = new uint256[](1);
                    r[0] = _a;
                }
                function arr(uint256 _a, uint256 _b) internal pure returns (uint256[] r) {
                    r = new uint256[](2);
                    r[0] = _a;
                    r[1] = _b;
                }
                function arr(uint256 _a, uint256 _b, uint256 _c) internal pure returns (uint256[] r) {
                    r = new uint256[](3);
                    r[0] = _a;
                    r[1] = _b;
                    r[2] = _c;
                }
                function arr(uint256 _a, uint256 _b, uint256 _c, uint256 _d) internal pure returns (uint256[] r) {
                    r = new uint256[](4);
                    r[0] = _a;
                    r[1] = _b;
                    r[2] = _c;
                    r[3] = _d;
                }
                function arr(uint256 _a, uint256 _b, uint256 _c, uint256 _d, uint256 _e) internal pure returns (uint256[] r) {
                    r = new uint256[](5);
                    r[0] = _a;
                    r[1] = _b;
                    r[2] = _c;
                    r[3] = _d;
                    r[4] = _e;
                }
            }
            contract ACLHelpers {
                function decodeParamOp(uint256 _x) internal pure returns (uint8 b) {
                    return uint8(_x >> (8 * 30));
                }
                function decodeParamId(uint256 _x) internal pure returns (uint8 b) {
                    return uint8(_x >> (8 * 31));
                }
                function decodeParamsList(uint256 _x) internal pure returns (uint32 a, uint32 b, uint32 c) {
                    a = uint32(_x);
                    b = uint32(_x >> (8 * 4));
                    c = uint32(_x >> (8 * 8));
                }
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            import "./Petrifiable.sol";
            contract Autopetrified is Petrifiable {
                constructor() public {
                    // Immediately petrify base (non-proxy) instances of inherited contracts on deploy.
                    // This renders them uninitializable (and unusable without a proxy).
                    petrify();
                }
            }
            pragma solidity ^0.4.24;
            library ConversionHelpers {
                string private constant ERROR_IMPROPER_LENGTH = "CONVERSION_IMPROPER_LENGTH";
                function dangerouslyCastUintArrayToBytes(uint256[] memory _input) internal pure returns (bytes memory output) {
                    // Force cast the uint256[] into a bytes array, by overwriting its length
                    // Note that the bytes array doesn't need to be initialized as we immediately overwrite it
                    // with the input and a new length. The input becomes invalid from this point forward.
                    uint256 byteLength = _input.length * 32;
                    assembly {
                        output := _input
                        mstore(output, byteLength)
                    }
                }
                function dangerouslyCastBytesToUintArray(bytes memory _input) internal pure returns (uint256[] memory output) {
                    // Force cast the bytes array into a uint256[], by overwriting its length
                    // Note that the uint256[] doesn't need to be initialized as we immediately overwrite it
                    // with the input and a new length. The input becomes invalid from this point forward.
                    uint256 intsLength = _input.length / 32;
                    require(_input.length == intsLength * 32, ERROR_IMPROPER_LENGTH);
                    assembly {
                        output := _input
                        mstore(output, intsLength)
                    }
                }
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            import "../common/UnstructuredStorage.sol";
            contract ReentrancyGuard {
                using UnstructuredStorage for bytes32;
                /* Hardcoded constants to save gas
                bytes32 internal constant REENTRANCY_MUTEX_POSITION = keccak256("aragonOS.reentrancyGuard.mutex");
                */
                bytes32 private constant REENTRANCY_MUTEX_POSITION = 0xe855346402235fdd185c890e68d2c4ecad599b88587635ee285bce2fda58dacb;
                string private constant ERROR_REENTRANT = "REENTRANCY_REENTRANT_CALL";
                modifier nonReentrant() {
                    // Ensure mutex is unlocked
                    require(!REENTRANCY_MUTEX_POSITION.getStorageBool(), ERROR_REENTRANT);
                    // Lock mutex before function call
                    REENTRANCY_MUTEX_POSITION.setStorageBool(true);
                    // Perform function call
                    _;
                    // Unlock mutex after function call
                    REENTRANCY_MUTEX_POSITION.setStorageBool(false);
                }
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            import "../lib/token/ERC20.sol";
            import "./EtherTokenConstant.sol";
            import "./IsContract.sol";
            import "./IVaultRecoverable.sol";
            import "./SafeERC20.sol";
            contract VaultRecoverable is IVaultRecoverable, EtherTokenConstant, IsContract {
                using SafeERC20 for ERC20;
                string private constant ERROR_DISALLOWED = "RECOVER_DISALLOWED";
                string private constant ERROR_VAULT_NOT_CONTRACT = "RECOVER_VAULT_NOT_CONTRACT";
                string private constant ERROR_TOKEN_TRANSFER_FAILED = "RECOVER_TOKEN_TRANSFER_FAILED";
                /**
                 * @notice Send funds to recovery Vault. This contract should never receive funds,
                 *         but in case it does, this function allows one to recover them.
                 * @param _token Token balance to be sent to recovery vault.
                 */
                function transferToVault(address _token) external {
                    require(allowRecoverability(_token), ERROR_DISALLOWED);
                    address vault = getRecoveryVault();
                    require(isContract(vault), ERROR_VAULT_NOT_CONTRACT);
                    uint256 balance;
                    if (_token == ETH) {
                        balance = address(this).balance;
                        vault.transfer(balance);
                    } else {
                        ERC20 token = ERC20(_token);
                        balance = token.staticBalanceOf(this);
                        require(token.safeTransfer(vault, balance), ERROR_TOKEN_TRANSFER_FAILED);
                    }
                    emit RecoverToVault(vault, _token, balance);
                }
                /**
                * @dev By default deriving from AragonApp makes it recoverable
                * @param token Token address that would be recovered
                * @return bool whether the app allows the recovery
                */
                function allowRecoverability(address token) public view returns (bool) {
                    return true;
                }
                // Cast non-implemented interface to be public so we can use it internally
                function getRecoveryVault() public view returns (address);
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            import "./IEVMScriptExecutor.sol";
            import "./IEVMScriptRegistry.sol";
            import "../apps/AppStorage.sol";
            import "../kernel/KernelConstants.sol";
            import "../common/Initializable.sol";
            contract EVMScriptRunner is AppStorage, Initializable, EVMScriptRegistryConstants, KernelNamespaceConstants {
                string private constant ERROR_EXECUTOR_UNAVAILABLE = "EVMRUN_EXECUTOR_UNAVAILABLE";
                string private constant ERROR_PROTECTED_STATE_MODIFIED = "EVMRUN_PROTECTED_STATE_MODIFIED";
                /* This is manually crafted in assembly
                string private constant ERROR_EXECUTOR_INVALID_RETURN = "EVMRUN_EXECUTOR_INVALID_RETURN";
                */
                event ScriptResult(address indexed executor, bytes script, bytes input, bytes returnData);
                function getEVMScriptExecutor(bytes _script) public view returns (IEVMScriptExecutor) {
                    return IEVMScriptExecutor(getEVMScriptRegistry().getScriptExecutor(_script));
                }
                function getEVMScriptRegistry() public view returns (IEVMScriptRegistry) {
                    address registryAddr = kernel().getApp(KERNEL_APP_ADDR_NAMESPACE, EVMSCRIPT_REGISTRY_APP_ID);
                    return IEVMScriptRegistry(registryAddr);
                }
                function runScript(bytes _script, bytes _input, address[] _blacklist)
                    internal
                    isInitialized
                    protectState
                    returns (bytes)
                {
                    IEVMScriptExecutor executor = getEVMScriptExecutor(_script);
                    require(address(executor) != address(0), ERROR_EXECUTOR_UNAVAILABLE);
                    bytes4 sig = executor.execScript.selector;
                    bytes memory data = abi.encodeWithSelector(sig, _script, _input, _blacklist);
                    bytes memory output;
                    assembly {
                        let success := delegatecall(
                            gas,                // forward all gas
                            executor,           // address
                            add(data, 0x20),    // calldata start
                            mload(data),        // calldata length
                            0,                  // don't write output (we'll handle this ourselves)
                            0                   // don't write output
                        )
                        output := mload(0x40) // free mem ptr get
                        switch success
                        case 0 {
                            // If the call errored, forward its full error data
                            returndatacopy(output, 0, returndatasize)
                            revert(output, returndatasize)
                        }
                        default {
                            switch gt(returndatasize, 0x3f)
                            case 0 {
                                // Need at least 0x40 bytes returned for properly ABI-encoded bytes values,
                                // revert with "EVMRUN_EXECUTOR_INVALID_RETURN"
                                // See remix: doing a `revert("EVMRUN_EXECUTOR_INVALID_RETURN")` always results in
                                // this memory layout
                                mstore(output, 0x08c379a000000000000000000000000000000000000000000000000000000000)         // error identifier
                                mstore(add(output, 0x04), 0x0000000000000000000000000000000000000000000000000000000000000020) // starting offset
                                mstore(add(output, 0x24), 0x000000000000000000000000000000000000000000000000000000000000001e) // reason length
                                mstore(add(output, 0x44), 0x45564d52554e5f4558454355544f525f494e56414c49445f52455455524e0000) // reason
                                revert(output, 100) // 100 = 4 + 3 * 32 (error identifier + 3 words for the ABI encoded error)
                            }
                            default {
                                // Copy result
                                //
                                // Needs to perform an ABI decode for the expected `bytes` return type of
                                // `executor.execScript()` as solidity will automatically ABI encode the returned bytes as:
                                //    [ position of the first dynamic length return value = 0x20 (32 bytes) ]
                                //    [ output length (32 bytes) ]
                                //    [ output content (N bytes) ]
                                //
                                // Perform the ABI decode by ignoring the first 32 bytes of the return data
                                let copysize := sub(returndatasize, 0x20)
                                returndatacopy(output, 0x20, copysize)
                                mstore(0x40, add(output, copysize)) // free mem ptr set
                            }
                        }
                    }
                    emit ScriptResult(address(executor), _script, _input, output);
                    return output;
                }
                modifier protectState {
                    address preKernel = address(kernel());
                    bytes32 preAppId = appId();
                    _; // exec
                    require(address(kernel()) == preKernel, ERROR_PROTECTED_STATE_MODIFIED);
                    require(appId() == preAppId, ERROR_PROTECTED_STATE_MODIFIED);
                }
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            library UnstructuredStorage {
                function getStorageBool(bytes32 position) internal view returns (bool data) {
                    assembly { data := sload(position) }
                }
                function getStorageAddress(bytes32 position) internal view returns (address data) {
                    assembly { data := sload(position) }
                }
                function getStorageBytes32(bytes32 position) internal view returns (bytes32 data) {
                    assembly { data := sload(position) }
                }
                function getStorageUint256(bytes32 position) internal view returns (uint256 data) {
                    assembly { data := sload(position) }
                }
                function setStorageBool(bytes32 position, bool data) internal {
                    assembly { sstore(position, data) }
                }
                function setStorageAddress(bytes32 position, address data) internal {
                    assembly { sstore(position, data) }
                }
                function setStorageBytes32(bytes32 position, bytes32 data) internal {
                    assembly { sstore(position, data) }
                }
                function setStorageUint256(bytes32 position, uint256 data) internal {
                    assembly { sstore(position, data) }
                }
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            import "../acl/IACL.sol";
            import "../common/IVaultRecoverable.sol";
            interface IKernelEvents {
                event SetApp(bytes32 indexed namespace, bytes32 indexed appId, address app);
            }
            // This should be an interface, but interfaces can't inherit yet :(
            contract IKernel is IKernelEvents, IVaultRecoverable {
                function acl() public view returns (IACL);
                function hasPermission(address who, address where, bytes32 what, bytes how) public view returns (bool);
                function setApp(bytes32 namespace, bytes32 appId, address app) public;
                function getApp(bytes32 namespace, bytes32 appId) public view returns (address);
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            interface IACL {
                function initialize(address permissionsCreator) external;
                // TODO: this should be external
                // See https://github.com/ethereum/solidity/issues/4832
                function hasPermission(address who, address where, bytes32 what, bytes how) public view returns (bool);
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            interface IVaultRecoverable {
                event RecoverToVault(address indexed vault, address indexed token, uint256 amount);
                function transferToVault(address token) external;
                function allowRecoverability(address token) external view returns (bool);
                function getRecoveryVault() external view returns (address);
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            import "./Initializable.sol";
            contract Petrifiable is Initializable {
                // Use block UINT256_MAX (which should be never) as the initializable date
                uint256 internal constant PETRIFIED_BLOCK = uint256(-1);
                function isPetrified() public view returns (bool) {
                    return getInitializationBlock() == PETRIFIED_BLOCK;
                }
                /**
                * @dev Function to be called by top level contract to prevent being initialized.
                *      Useful for freezing base contracts when they're used behind proxies.
                */
                function petrify() internal onlyInit {
                    initializedAt(PETRIFIED_BLOCK);
                }
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            import "./TimeHelpers.sol";
            import "./UnstructuredStorage.sol";
            contract Initializable is TimeHelpers {
                using UnstructuredStorage for bytes32;
                // keccak256("aragonOS.initializable.initializationBlock")
                bytes32 internal constant INITIALIZATION_BLOCK_POSITION = 0xebb05b386a8d34882b8711d156f463690983dc47815980fb82aeeff1aa43579e;
                string private constant ERROR_ALREADY_INITIALIZED = "INIT_ALREADY_INITIALIZED";
                string private constant ERROR_NOT_INITIALIZED = "INIT_NOT_INITIALIZED";
                modifier onlyInit {
                    require(getInitializationBlock() == 0, ERROR_ALREADY_INITIALIZED);
                    _;
                }
                modifier isInitialized {
                    require(hasInitialized(), ERROR_NOT_INITIALIZED);
                    _;
                }
                /**
                * @return Block number in which the contract was initialized
                */
                function getInitializationBlock() public view returns (uint256) {
                    return INITIALIZATION_BLOCK_POSITION.getStorageUint256();
                }
                /**
                * @return Whether the contract has been initialized by the time of the current block
                */
                function hasInitialized() public view returns (bool) {
                    uint256 initializationBlock = getInitializationBlock();
                    return initializationBlock != 0 && getBlockNumber() >= initializationBlock;
                }
                /**
                * @dev Function to be called by top level contract after initialization has finished.
                */
                function initialized() internal onlyInit {
                    INITIALIZATION_BLOCK_POSITION.setStorageUint256(getBlockNumber());
                }
                /**
                * @dev Function to be called by top level contract after initialization to enable the contract
                *      at a future block number rather than immediately.
                */
                function initializedAt(uint256 _blockNumber) internal onlyInit {
                    INITIALIZATION_BLOCK_POSITION.setStorageUint256(_blockNumber);
                }
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            import "./Uint256Helpers.sol";
            contract TimeHelpers {
                using Uint256Helpers for uint256;
                /**
                * @dev Returns the current block number.
                *      Using a function rather than `block.number` allows us to easily mock the block number in
                *      tests.
                */
                function getBlockNumber() internal view returns (uint256) {
                    return block.number;
                }
                /**
                * @dev Returns the current block number, converted to uint64.
                *      Using a function rather than `block.number` allows us to easily mock the block number in
                *      tests.
                */
                function getBlockNumber64() internal view returns (uint64) {
                    return getBlockNumber().toUint64();
                }
                /**
                * @dev Returns the current timestamp.
                *      Using a function rather than `block.timestamp` allows us to easily mock it in
                *      tests.
                */
                function getTimestamp() internal view returns (uint256) {
                    return block.timestamp; // solium-disable-line security/no-block-members
                }
                /**
                * @dev Returns the current timestamp, converted to uint64.
                *      Using a function rather than `block.timestamp` allows us to easily mock it in
                *      tests.
                */
                function getTimestamp64() internal view returns (uint64) {
                    return getTimestamp().toUint64();
                }
            }
            pragma solidity ^0.4.24;
            library Uint256Helpers {
                uint256 private constant MAX_UINT64 = uint64(-1);
                string private constant ERROR_NUMBER_TOO_BIG = "UINT64_NUMBER_TOO_BIG";
                function toUint64(uint256 a) internal pure returns (uint64) {
                    require(a <= MAX_UINT64, ERROR_NUMBER_TOO_BIG);
                    return uint64(a);
                }
            }
            // See https://github.com/OpenZeppelin/openzeppelin-solidity/blob/a9f910d34f0ab33a1ae5e714f69f9596a02b4d91/contracts/token/ERC20/ERC20.sol
            pragma solidity ^0.4.24;
            /**
             * @title ERC20 interface
             * @dev see https://github.com/ethereum/EIPs/issues/20
             */
            contract ERC20 {
                function totalSupply() public view returns (uint256);
                function balanceOf(address _who) public view returns (uint256);
                function allowance(address _owner, address _spender)
                    public view returns (uint256);
                function transfer(address _to, uint256 _value) public returns (bool);
                function approve(address _spender, uint256 _value)
                    public returns (bool);
                function transferFrom(address _from, address _to, uint256 _value)
                    public returns (bool);
                event Transfer(
                    address indexed from,
                    address indexed to,
                    uint256 value
                );
                event Approval(
                    address indexed owner,
                    address indexed spender,
                    uint256 value
                );
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            // aragonOS and aragon-apps rely on address(0) to denote native ETH, in
            // contracts where both tokens and ETH are accepted
            contract EtherTokenConstant {
                address internal constant ETH = address(0);
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            contract IsContract {
                /*
                * NOTE: this should NEVER be used for authentication
                * (see pitfalls: https://github.com/fergarrui/ethereum-security/tree/master/contracts/extcodesize).
                *
                * This is only intended to be used as a sanity check that an address is actually a contract,
                * RATHER THAN an address not being a contract.
                */
                function isContract(address _target) internal view returns (bool) {
                    if (_target == address(0)) {
                        return false;
                    }
                    uint256 size;
                    assembly { size := extcodesize(_target) }
                    return size > 0;
                }
            }
            // Inspired by AdEx (https://github.com/AdExNetwork/adex-protocol-eth/blob/b9df617829661a7518ee10f4cb6c4108659dd6d5/contracts/libs/SafeERC20.sol)
            // and 0x (https://github.com/0xProject/0x-monorepo/blob/737d1dc54d72872e24abce5a1dbe1b66d35fa21a/contracts/protocol/contracts/protocol/AssetProxy/ERC20Proxy.sol#L143)
            pragma solidity ^0.4.24;
            import "../lib/token/ERC20.sol";
            library SafeERC20 {
                // Before 0.5, solidity has a mismatch between `address.transfer()` and `token.transfer()`:
                // https://github.com/ethereum/solidity/issues/3544
                bytes4 private constant TRANSFER_SELECTOR = 0xa9059cbb;
                string private constant ERROR_TOKEN_BALANCE_REVERTED = "SAFE_ERC_20_BALANCE_REVERTED";
                string private constant ERROR_TOKEN_ALLOWANCE_REVERTED = "SAFE_ERC_20_ALLOWANCE_REVERTED";
                function invokeAndCheckSuccess(address _addr, bytes memory _calldata)
                    private
                    returns (bool)
                {
                    bool ret;
                    assembly {
                        let ptr := mload(0x40)    // free memory pointer
                        let success := call(
                            gas,                  // forward all gas
                            _addr,                // address
                            0,                    // no value
                            add(_calldata, 0x20), // calldata start
                            mload(_calldata),     // calldata length
                            ptr,                  // write output over free memory
                            0x20                  // uint256 return
                        )
                        if gt(success, 0) {
                            // Check number of bytes returned from last function call
                            switch returndatasize
                            // No bytes returned: assume success
                            case 0 {
                                ret := 1
                            }
                            // 32 bytes returned: check if non-zero
                            case 0x20 {
                                // Only return success if returned data was true
                                // Already have output in ptr
                                ret := eq(mload(ptr), 1)
                            }
                            // Not sure what was returned: don't mark as success
                            default { }
                        }
                    }
                    return ret;
                }
                function staticInvoke(address _addr, bytes memory _calldata)
                    private
                    view
                    returns (bool, uint256)
                {
                    bool success;
                    uint256 ret;
                    assembly {
                        let ptr := mload(0x40)    // free memory pointer
                        success := staticcall(
                            gas,                  // forward all gas
                            _addr,                // address
                            add(_calldata, 0x20), // calldata start
                            mload(_calldata),     // calldata length
                            ptr,                  // write output over free memory
                            0x20                  // uint256 return
                        )
                        if gt(success, 0) {
                            ret := mload(ptr)
                        }
                    }
                    return (success, ret);
                }
                /**
                * @dev Same as a standards-compliant ERC20.transfer() that never reverts (returns false).
                *      Note that this makes an external call to the token.
                */
                function safeTransfer(ERC20 _token, address _to, uint256 _amount) internal returns (bool) {
                    bytes memory transferCallData = abi.encodeWithSelector(
                        TRANSFER_SELECTOR,
                        _to,
                        _amount
                    );
                    return invokeAndCheckSuccess(_token, transferCallData);
                }
                /**
                * @dev Same as a standards-compliant ERC20.transferFrom() that never reverts (returns false).
                *      Note that this makes an external call to the token.
                */
                function safeTransferFrom(ERC20 _token, address _from, address _to, uint256 _amount) internal returns (bool) {
                    bytes memory transferFromCallData = abi.encodeWithSelector(
                        _token.transferFrom.selector,
                        _from,
                        _to,
                        _amount
                    );
                    return invokeAndCheckSuccess(_token, transferFromCallData);
                }
                /**
                * @dev Same as a standards-compliant ERC20.approve() that never reverts (returns false).
                *      Note that this makes an external call to the token.
                */
                function safeApprove(ERC20 _token, address _spender, uint256 _amount) internal returns (bool) {
                    bytes memory approveCallData = abi.encodeWithSelector(
                        _token.approve.selector,
                        _spender,
                        _amount
                    );
                    return invokeAndCheckSuccess(_token, approveCallData);
                }
                /**
                * @dev Static call into ERC20.balanceOf().
                * Reverts if the call fails for some reason (should never fail).
                */
                function staticBalanceOf(ERC20 _token, address _owner) internal view returns (uint256) {
                    bytes memory balanceOfCallData = abi.encodeWithSelector(
                        _token.balanceOf.selector,
                        _owner
                    );
                    (bool success, uint256 tokenBalance) = staticInvoke(_token, balanceOfCallData);
                    require(success, ERROR_TOKEN_BALANCE_REVERTED);
                    return tokenBalance;
                }
                /**
                * @dev Static call into ERC20.allowance().
                * Reverts if the call fails for some reason (should never fail).
                */
                function staticAllowance(ERC20 _token, address _owner, address _spender) internal view returns (uint256) {
                    bytes memory allowanceCallData = abi.encodeWithSelector(
                        _token.allowance.selector,
                        _owner,
                        _spender
                    );
                    (bool success, uint256 allowance) = staticInvoke(_token, allowanceCallData);
                    require(success, ERROR_TOKEN_ALLOWANCE_REVERTED);
                    return allowance;
                }
                /**
                * @dev Static call into ERC20.totalSupply().
                * Reverts if the call fails for some reason (should never fail).
                */
                function staticTotalSupply(ERC20 _token) internal view returns (uint256) {
                    bytes memory totalSupplyCallData = abi.encodeWithSelector(_token.totalSupply.selector);
                    (bool success, uint256 totalSupply) = staticInvoke(_token, totalSupplyCallData);
                    require(success, ERROR_TOKEN_ALLOWANCE_REVERTED);
                    return totalSupply;
                }
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            interface IEVMScriptExecutor {
                function execScript(bytes script, bytes input, address[] blacklist) external returns (bytes);
                function executorType() external pure returns (bytes32);
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            import "./IEVMScriptExecutor.sol";
            contract EVMScriptRegistryConstants {
                /* Hardcoded constants to save gas
                bytes32 internal constant EVMSCRIPT_REGISTRY_APP_ID = apmNamehash("evmreg");
                */
                bytes32 internal constant EVMSCRIPT_REGISTRY_APP_ID = 0xddbcfd564f642ab5627cf68b9b7d374fb4f8a36e941a75d89c87998cef03bd61;
            }
            interface IEVMScriptRegistry {
                function addScriptExecutor(IEVMScriptExecutor executor) external returns (uint id);
                function disableScriptExecutor(uint256 executorId) external;
                // TODO: this should be external
                // See https://github.com/ethereum/solidity/issues/4832
                function getScriptExecutor(bytes script) public view returns (IEVMScriptExecutor);
            }
            /*
             * SPDX-License-Identifier:    MIT
             */
            pragma solidity ^0.4.24;
            contract KernelAppIds {
                /* Hardcoded constants to save gas
                bytes32 internal constant KERNEL_CORE_APP_ID = apmNamehash("kernel");
                bytes32 internal constant KERNEL_DEFAULT_ACL_APP_ID = apmNamehash("acl");
                bytes32 internal constant KERNEL_DEFAULT_VAULT_APP_ID = apmNamehash("vault");
                */
                bytes32 internal constant KERNEL_CORE_APP_ID = 0x3b4bf6bf3ad5000ecf0f989d5befde585c6860fea3e574a4fab4c49d1c177d9c;
                bytes32 internal constant KERNEL_DEFAULT_ACL_APP_ID = 0xe3262375f45a6e2026b7e7b18c2b807434f2508fe1a2a3dfb493c7df8f4aad6a;
                bytes32 internal constant KERNEL_DEFAULT_VAULT_APP_ID = 0x7e852e0fcfce6551c13800f1e7476f982525c2b5277ba14b24339c68416336d1;
            }
            contract KernelNamespaceConstants {
                /* Hardcoded constants to save gas
                bytes32 internal constant KERNEL_CORE_NAMESPACE = keccak256("core");
                bytes32 internal constant KERNEL_APP_BASES_NAMESPACE = keccak256("base");
                bytes32 internal constant KERNEL_APP_ADDR_NAMESPACE = keccak256("app");
                */
                bytes32 internal constant KERNEL_CORE_NAMESPACE = 0xc681a85306374a5ab27f0bbc385296a54bcd314a1948b6cf61c4ea1bc44bb9f8;
                bytes32 internal constant KERNEL_APP_BASES_NAMESPACE = 0xf1f3eb40f5bc1ad1344716ced8b8a0431d840b5783aea1fd01786bc26f35ac0f;
                bytes32 internal constant KERNEL_APP_ADDR_NAMESPACE = 0xd6f028ca0e8edb4a8c9757ca4fdccab25fa1e0317da1188108f7d2dee14902fb;
            }
            pragma solidity ^0.4.24;
            /**
             * @title ERC20 interface
             * @dev see https://github.com/ethereum/EIPs/issues/20
             */
            interface IERC20 {
              function totalSupply() external view returns (uint256);
              function balanceOf(address who) external view returns (uint256);
              function allowance(address owner, address spender)
                external view returns (uint256);
              function transfer(address to, uint256 value) external returns (bool);
              function approve(address spender, uint256 value)
                external returns (bool);
              function transferFrom(address from, address to, uint256 value)
                external returns (bool);
              event Transfer(
                address indexed from,
                address indexed to,
                uint256 value
              );
              event Approval(
                address indexed owner,
                address indexed spender,
                uint256 value
              );
            }
            // SPDX-FileCopyrightText: 2020 Lido <[email protected]>
            // SPDX-License-Identifier: GPL-3.0
            pragma solidity 0.4.24;
            import "@aragon/os/contracts/common/UnstructuredStorage.sol";
            contract Pausable {
                using UnstructuredStorage for bytes32;
                event Stopped();
                event Resumed();
                bytes32 internal constant ACTIVE_FLAG_POSITION = keccak256("lido.Pausable.activeFlag");
                modifier whenNotStopped() {
                    require(ACTIVE_FLAG_POSITION.getStorageBool(), "CONTRACT_IS_STOPPED");
                    _;
                }
                modifier whenStopped() {
                    require(!ACTIVE_FLAG_POSITION.getStorageBool(), "CONTRACT_IS_ACTIVE");
                    _;
                }
                function isStopped() external view returns (bool) {
                    return !ACTIVE_FLAG_POSITION.getStorageBool();
                }
                function _stop() internal whenNotStopped {
                    ACTIVE_FLAG_POSITION.setStorageBool(false);
                    emit Stopped();
                }
                function _resume() internal whenStopped {
                    ACTIVE_FLAG_POSITION.setStorageBool(true);
                    emit Resumed();
                }
            }