Contract

Contract Source Code (Solidity)

IDE

• Blockscan IDE
• 🤖 Code ReaderBeta
• Remix IDE

Outline

• interface IOwned
•    - function owner()
•    - function transferOwnership(address _n ...
•    - function acceptOwnership()
•  contract Owned is IOwned
•    - function _ownerOnly()
•    - function transferOwnership(address _n ...
•    - function acceptOwnership()
•  contract Utils
•    - function _greaterThanZero(uint256 _va ...
•    - function _validAddress(address _addre ...
•    - function _notThis(address _address)
•    - function _validExternalAddress(addres ...
• interface IERC20Token
•    - function name()
•    - function symbol()
•    - function decimals()
•    - function totalSupply()
•    - function balanceOf(address _owner)
•    - function allowance(address _owner, ad ...
•    - function transfer(address _to, uint25 ...
•    - function transferFrom(
•    - function approve(address _spender, ui ...
•  contract TokenHandler
•    - function safeApprove(
•    - function safeTransfer(
•    - function safeTransferFrom(
• interface ITokenHolder is IOwned
•    - function withdrawTokens(
•  contract TokenHolder is ITokenHold ... *
•    - function withdrawTokens(

More Options

• Similar
• Sol2Uml
• Submit Audit
• Compare

/**
 *Submitted for verification at Etherscan.io on 2021-02-02
*/

// File: solidity/contracts/utility/interfaces/IOwned.sol

// SPDX-License-Identifier: SEE LICENSE IN LICENSE
pragma solidity 0.6.12;

/*
    Owned contract interface
*/
interface IOwned {
    // this function isn't since the compiler emits automatically generated getter functions as external
    function owner() external view returns (address);

    function transferOwnership(address _newOwner) external;

    function acceptOwnership() external;
}

// File: solidity/contracts/utility/Owned.sol


pragma solidity 0.6.12;


/**
 * @dev This contract provides support and utilities for contract ownership.
 */
contract Owned is IOwned {
    address public override owner;
    address public newOwner;

    /**
     * @dev triggered when the owner is updated
     *
     * @param _prevOwner previous owner
     * @param _newOwner  new owner
     */
    event OwnerUpdate(address indexed _prevOwner, address indexed _newOwner);

    /**
     * @dev initializes a new Owned instance
     */
    constructor() public {
        owner = msg.sender;
    }

    // allows execution by the owner only
    modifier ownerOnly {
        _ownerOnly();
        _;
    }

    // error message binary size optimization
    function _ownerOnly() internal view {
        require(msg.sender == owner, "ERR_ACCESS_DENIED");
    }

    /**
     * @dev allows transferring the contract ownership
     * the new owner still needs to accept the transfer
     * can only be called by the contract owner
     *
     * @param _newOwner    new contract owner
     */
    function transferOwnership(address _newOwner) public override ownerOnly {
        require(_newOwner != owner, "ERR_SAME_OWNER");
        newOwner = _newOwner;
    }

    /**
     * @dev used by a new owner to accept an ownership transfer
     */
    function acceptOwnership() public override {
        require(msg.sender == newOwner, "ERR_ACCESS_DENIED");
        emit OwnerUpdate(owner, newOwner);
        owner = newOwner;
        newOwner = address(0);
    }
}

// File: solidity/contracts/utility/Utils.sol


pragma solidity 0.6.12;

/**
 * @dev Utilities & Common Modifiers
 */
contract Utils {
    // verifies that a value is greater than zero
    modifier greaterThanZero(uint256 _value) {
        _greaterThanZero(_value);
        _;
    }

    // error message binary size optimization
    function _greaterThanZero(uint256 _value) internal pure {
        require(_value > 0, "ERR_ZERO_VALUE");
    }

    // validates an address - currently only checks that it isn't null
    modifier validAddress(address _address) {
        _validAddress(_address);
        _;
    }

    // error message binary size optimization
    function _validAddress(address _address) internal pure {
        require(_address != address(0), "ERR_INVALID_ADDRESS");
    }

    // verifies that the address is different than this contract address
    modifier notThis(address _address) {
        _notThis(_address);
        _;
    }

    // error message binary size optimization
    function _notThis(address _address) internal view {
        require(_address != address(this), "ERR_ADDRESS_IS_SELF");
    }

    // validates an external address - currently only checks that it isn't null or this
    modifier validExternalAddress(address _address) {
        _validExternalAddress(_address);
        _;
    }

    // error message binary size optimization
    function _validExternalAddress(address _address) internal view {
        require(_address != address(0) && _address != address(this), "ERR_INVALID_EXTERNAL_ADDRESS");
    }
}

// File: solidity/contracts/token/interfaces/IERC20Token.sol


pragma solidity 0.6.12;

/*
    ERC20 Standard Token interface
*/
interface IERC20Token {
    function name() external view returns (string memory);

    function symbol() external view returns (string memory);

    function decimals() external view returns (uint8);

    function totalSupply() external view returns (uint256);

    function balanceOf(address _owner) external view returns (uint256);

    function allowance(address _owner, address _spender) external view returns (uint256);

    function transfer(address _to, uint256 _value) external returns (bool);

    function transferFrom(
        address _from,
        address _to,
        uint256 _value
    ) external returns (bool);

    function approve(address _spender, uint256 _value) external returns (bool);
}

// File: solidity/contracts/utility/TokenHandler.sol


pragma solidity 0.6.12;


contract TokenHandler {
    bytes4 private constant APPROVE_FUNC_SELECTOR = bytes4(keccak256("approve(address,uint256)"));
    bytes4 private constant TRANSFER_FUNC_SELECTOR = bytes4(keccak256("transfer(address,uint256)"));
    bytes4 private constant TRANSFER_FROM_FUNC_SELECTOR = bytes4(keccak256("transferFrom(address,address,uint256)"));

    /**
     * @dev executes the ERC20 token's `approve` function and reverts upon failure
     * the main purpose of this function is to prevent a non standard ERC20 token
     * from failing silently
     *
     * @param _token   ERC20 token address
     * @param _spender approved address
     * @param _value   allowance amount
     */
    function safeApprove(
        IERC20Token _token,
        address _spender,
        uint256 _value
    ) internal {
        (bool success, bytes memory data) = address(_token).call(
            abi.encodeWithSelector(APPROVE_FUNC_SELECTOR, _spender, _value)
        );
        require(success && (data.length == 0 || abi.decode(data, (bool))), "ERR_APPROVE_FAILED");
    }

    /**
     * @dev executes the ERC20 token's `transfer` function and reverts upon failure
     * the main purpose of this function is to prevent a non standard ERC20 token
     * from failing silently
     *
     * @param _token   ERC20 token address
     * @param _to      target address
     * @param _value   transfer amount
     */
    function safeTransfer(
        IERC20Token _token,
        address _to,
        uint256 _value
    ) internal {
        (bool success, bytes memory data) = address(_token).call(
            abi.encodeWithSelector(TRANSFER_FUNC_SELECTOR, _to, _value)
        );
        require(success && (data.length == 0 || abi.decode(data, (bool))), "ERR_TRANSFER_FAILED");
    }

    /**
     * @dev executes the ERC20 token's `transferFrom` function and reverts upon failure
     * the main purpose of this function is to prevent a non standard ERC20 token
     * from failing silently
     *
     * @param _token   ERC20 token address
     * @param _from    source address
     * @param _to      target address
     * @param _value   transfer amount
     */
    function safeTransferFrom(
        IERC20Token _token,
        address _from,
        address _to,
        uint256 _value
    ) internal {
        (bool success, bytes memory data) = address(_token).call(
            abi.encodeWithSelector(TRANSFER_FROM_FUNC_SELECTOR, _from, _to, _value)
        );
        require(success && (data.length == 0 || abi.decode(data, (bool))), "ERR_TRANSFER_FROM_FAILED");
    }
}

// File: solidity/contracts/utility/interfaces/ITokenHolder.sol


pragma solidity 0.6.12;



/*
    Token Holder interface
*/
interface ITokenHolder is IOwned {
    function withdrawTokens(
        IERC20Token _token,
        address _to,
        uint256 _amount
    ) external;
}

// File: solidity/contracts/utility/TokenHolder.sol


pragma solidity 0.6.12;






/**
 * @dev This contract provides a safety mechanism for allowing the owner to
 * send tokens that were sent to the contract by mistake back to the sender.
 *
 * We consider every contract to be a 'token holder' since it's currently not possible
 * for a contract to deny receiving tokens.
 *
 * Note that we use the non standard ERC-20 interface which has no return value for transfer
 * in order to support both non standard as well as standard token contracts.
 * see https://github.com/ethereum/solidity/issues/4116
 */
contract TokenHolder is ITokenHolder, TokenHandler, Owned, Utils {
    /**
     * @dev withdraws tokens held by the contract and sends them to an account
     * can only be called by the owner
     *
     * @param _token   ERC20 token contract address
     * @param _to      account to receive the new amount
     * @param _amount  amount to withdraw
     */
    function withdrawTokens(
        IERC20Token _token,
        address _to,
        uint256 _amount
    ) public virtual override ownerOnly validAddress(address(_token)) validAddress(_to) notThis(_to) {
        safeTransfer(_token, _to, _amount);
    }
}

• No Contract Security Audit Submitted- Submit Audit Here

[{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"_prevOwner","type":"address"},{"indexed":true,"internalType":"address","name":"_newOwner","type":"address"}],"name":"OwnerUpdate","type":"event"},{"inputs":[],"name":"acceptOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"newOwner","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"owner","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"_newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"contract IERC20Token","name":"_token","type":"address"},{"internalType":"address","name":"_to","type":"address"},{"internalType":"uint256","name":"_amount","type":"uint256"}],"name":"withdrawTokens","outputs":[],"stateMutability":"nonpayable","type":"function"}]

608060405234801561001057600080fd5b50600080546001600160a01b0319163317905561050d806100326000396000f3fe608060405234801561001057600080fd5b50600436106100575760003560e01c80635e35359e1461005c57806379ba5097146100945780638da5cb5b1461009c578063d4ee1d90146100c0578063f2fde38b146100c8575b600080fd5b6100926004803603606081101561007257600080fd5b506001600160a01b038135811691602081013590911690604001356100ee565b005b610092610127565b6100a46101de565b604080516001600160a01b039092168252519081900360200190f35b6100a46101ed565b610092600480360360208110156100de57600080fd5b50356001600160a01b03166101fc565b6100f661027a565b82610100816102cf565b8261010a816102cf565b8361011481610323565b61011f868686610377565b505050505050565b6001546001600160a01b0316331461017a576040805162461bcd60e51b815260206004820152601160248201527011549497d050d0d154d4d7d11153925151607a1b604482015290519081900360640190fd5b600154600080546040516001600160a01b0393841693909116917f343765429aea5a34b3ff6a3785a98a5abb2597aca87bfbb58632c173d585373a91a360018054600080546001600160a01b03199081166001600160a01b03841617909155169055565b6000546001600160a01b031681565b6001546001600160a01b031681565b61020461027a565b6000546001600160a01b0382811691161415610258576040805162461bcd60e51b815260206004820152600e60248201526d22a9292fa9a0a6a2afa7aba722a960911b604482015290519081900360640190fd5b600180546001600160a01b0319166001600160a01b0392909216919091179055565b6000546001600160a01b031633146102cd576040805162461bcd60e51b815260206004820152601160248201527011549497d050d0d154d4d7d11153925151607a1b604482015290519081900360640190fd5b565b6001600160a01b038116610320576040805162461bcd60e51b81526020600482015260136024820152724552525f494e56414c49445f4144445245535360681b604482015290519081900360640190fd5b50565b6001600160a01b038116301415610320576040805162461bcd60e51b815260206004820152601360248201527222a9292fa0a2222922a9a9afa4a9afa9a2a62360691b604482015290519081900360640190fd5b604080516001600160a01b038481166024830152604480830185905283518084039091018152606490920183526020820180516001600160e01b031663a9059cbb60e01b178152925182516000946060949389169392918291908083835b602083106103f45780518252601f1990920191602091820191016103d5565b6001836020036101000a0380198251168184511680821785525050505050509050019150506000604051808303816000865af19150503d8060008114610456576040519150601f19603f3d011682016040523d82523d6000602084013e61045b565b606091505b5091509150818015610489575080511580610489575080806020019051602081101561048657600080fd5b50515b6104d0576040805162461bcd60e51b815260206004820152601360248201527211549497d514905394d1915497d19052531151606a1b604482015290519081900360640190fd5b505050505056fea26469706673582212205713b0ccdef41d2831710b19f0c66ce97117db944330659f41c13764564658bf64736f6c634300060c0033

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