Contract 0x7ffb3d637014488b63fb9858e279385685afc1e2 3

 
 
Txn Hash
Method
Block
From
To
Value [Txn Fee]
0x1ee280897938991348073408cdff3f9749a77a87772d0ee12b120d9d98f5b3a0Approve435346812023-06-04 22:17:421 hr 27 mins ago0x6b6b0e6302ff4fb3dc1b3380f519b5613738d307 IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.00465025264175.719945619
0x3015e9c3cc6677f85afe382302e8524c5fab143f7c1d3625b5392e5373735733Approve435345992023-06-04 22:14:481 hr 30 mins ago0x6b6b0e6302ff4fb3dc1b3380f519b5613738d307 IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.004031707235152.346857459
0x2d5b876ae1f635ea601bf12ae8031a9bb0ae560d8b61dc2a9ad0bfb2e9026fe5Approve435344982023-06-04 22:10:181 hr 34 mins ago0x6b6b0e6302ff4fb3dc1b3380f519b5613738d307 IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.007143043424154.064434143
0x8ca87ae7e81598a1750e52b530e60951ccd6d66df48e91a7c8da7edadadbb4a5Approve435171772023-06-04 11:21:2112 hrs 23 mins ago0xcc3deee07a922f9b64da3729df72f5e945cad38d IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.004745008743 162.14491333
0x111f83c5b499e1336549fe0290198336a0debcf81eb0bb151d78201816a3bedfApprove435171102023-06-04 11:18:5912 hrs 26 mins ago0xcc3deee07a922f9b64da3729df72f5e945cad38d IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.005162599635 176.34238406
0xd03b335f2e2d5818ec7d86e8582badc78145b586195e50462bfb72706d87a745Approve435171082023-06-04 11:18:5512 hrs 26 mins ago0xcc3deee07a922f9b64da3729df72f5e945cad38d IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.00534305421 182.581130746
0x451a4c769f42fad3f3b9dd6acf3c6b3cd71b52cfde19461a10f920e6e46b9927Approve435170692023-06-04 11:17:3112 hrs 27 mins ago0xcc3deee07a922f9b64da3729df72f5e945cad38d IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.007639886191 164.737928923
0x253c436d7e21fde74f3315ebbfe6ead0d738ddd61c0b4c4a5a0360da975e3d9fIncrease Allowan...433668012023-05-31 11:58:544 days 11 hrs ago0xf5444a4bedbeb1fc30574d4c0565788ec00aa1f0 IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.00772790312 165.369949719
0x8b590956cd8fc08321c66f4d1787ee7896e5eeb924982491b45f3d545f1b3454Transfer From432419532023-05-28 8:17:407 days 15 hrs ago0xb05ecb70f691c5eca01287f6f7664ec7075a17e2 IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.003729167648 147.689807867
0xc33dedc22bce3e06b3623adb14682c68109ecfb5b088a68e634e63824a5a37d4Transfer From432418342023-05-28 8:13:267 days 15 hrs ago0xb05ecb70f691c5eca01287f6f7664ec7075a17e2 IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.003769052745 149.269415679
0xa79e9bb7586b9dd57775b319cd23411fa5cad329c8fa48d16ac0d36f74d6dc22Approve430087292023-05-22 9:28:2613 days 14 hrs ago0x227c1456dc417f632385592f4e5591042eee98fc IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.0052822144 199.6
0x2f2fe8f6c593ff47f20ed154fdb42c862ddf90563f387884967cb2eb64bc2b49Approve430083912023-05-22 9:14:3613 days 14 hrs ago0x227c1456dc417f632385592f4e5591042eee98fc IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.004776752 180.5
0x796c9c1ea1189a0e25a362d1e1186c64959286a6365eae32ebc50505c1868d58Approve430070292023-05-22 8:22:0613 days 15 hrs ago0x227c1456dc417f632385592f4e5591042eee98fc IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.0045676864 172.6
0xa5794f3863f79bd504a541c493424ab7e842ba3596c1bb7bcb438c8ef4dde46cApprove430065992023-05-22 8:05:4813 days 15 hrs ago0x227c1456dc417f632385592f4e5591042eee98fc IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.0055098048 208.2
0xbeec8155b1fb1683c444c9a52d01ec48a8209e7f006c63bc03dc79ab8b16aa60Approve430065272023-05-22 8:03:1413 days 15 hrs ago0x227c1456dc417f632385592f4e5591042eee98fc IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.0073208756 157.9
0x23366e8c1d507aef3dc51042fa5de0e27005d937b67e0b2ac8d5d05b4d95eef8Approve425155232023-05-10 1:45:0025 days 22 hrs ago0xbc5883c73141bf78a70aac505e9e98e4b57ad4d8 IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.007679598233 165.465789751
0x85acbe128dc0e8cc52e49b8c55c47d9b34426760ab63d6ff476fffc094d647d9Approve421788612023-05-01 14:08:4634 days 9 hrs ago0xd4a951fb0a0e8066a3cecf77835a86cec7c97778 IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.013840139242 298.587746871
0x49d34fe7163f4535e79ceddc13df67de2a0033325c624f7e0653f726e5fcbd88Approve421713392023-05-01 9:37:5834 days 14 hrs ago0x9691a7e086a6f8dc54faf8d9056f1e18bb1e4beb IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.012666717119 272.919010594
0xc84d557d5e8f9a1da9d2719cb7e74dec7df739ff8ca6a6581e99ebd784484c03Approve420112772023-04-27 7:17:1138 days 16 hrs ago0xebd209df078575c999155258f0ac754e42421633 IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.032427858068699.599975586
0xb5059133dfee4de1be37362aae5037ef422aa63f8a42139d0b0a2c11901397e9Transfer From418415022023-04-22 22:26:2243 days 1 hr ago0xa24fcdf2e3880a2159f8b00b07f34191a57b7a58 IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.005991999791236.969065543
0x7c7946887636f95783dc916f2262a0f8d86a3b71d13768319d52134ebe6b8f7cApprove416764602023-04-18 15:33:1847 days 8 hrs ago0x1487ec91b167542acfbd11a577a04f265cbce3cf IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.00974148 210
0xd8627fa3e50827df91045573a93d657c2da08412dc09b97e362766c41c29eb53Approve415249432023-04-14 14:24:2251 days 9 hrs ago0x84cc1ac7c1f8d4cbe471a6c229cbf4dc459457a7 IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.014632 500
0x73419190e4925062e4bd98ecba95751320ebebcf2410249a6489792f635e35e5Approve415211342023-04-14 12:05:3551 days 11 hrs ago0x65c0efa8c834999b18c6f0e335d452176954efec IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.006126054981 250.780046727
0x29501346e60b14a1da23ffa1b39e871ee4018ab47bcd54501766ddeb6d9c7a12Approve415163392023-04-14 9:09:3251 days 14 hrs ago0x74375e12e9a9111993866b2377ecce827f16e0f4 IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.018596776 401
0xdc1bea7bbc1f97fe33bd4b9dd5d6208a333802636fa4dc810765fa65d88a2f3cApprove415149662023-04-14 8:18:2351 days 15 hrs ago0x65c0efa8c834999b18c6f0e335d452176954efec IN  0x7ffb3d637014488b63fb9858e279385685afc1e20 MATIC0.023602279165 508.933050835
[ Download CSV Export 
Parent Txn Hash Block From To Value
Loading

Contract Source Code Verified (Exact Match)

Contract Name:
UChildERC20

Compiler Version
v0.6.6+commit.6c089d02

Optimization Enabled:
No with 200 runs

Other Settings:
default evmVersion, None license

Contract Source Code (Solidity)

/**
 *Submitted for verification at polygonscan.com on 2021-06-29
*/

// File: @openzeppelin/contracts/GSN/Context.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.6.0;

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.6.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

// File: @openzeppelin/contracts/math/SafeMath.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.6.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return mod(a, b, "SafeMath: modulo by zero");
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

// File: @openzeppelin/contracts/utils/Address.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.6.2;

/**
 * @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
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // According to EIP-1052, 0x0 is the value returned for not-yet created accounts
        // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
        // for accounts without code, i.e. `keccak256('')`
        bytes32 codehash;
        bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
        // solhint-disable-next-line no-inline-assembly
        assembly { codehash := extcodehash(account) }
        return (codehash != accountHash && codehash != 0x0);
    }

    /**
     * @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");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (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 functionCall(target, data, "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");
        return _functionCallWithValue(target, data, value, errorMessage);
    }

    function _functionCallWithValue(address target, bytes memory data, uint256 weiValue, string memory errorMessage) private returns (bytes memory) {
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: weiValue }(data);
        if (success) {
            return returndata;
        } else {
            // 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

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// File: contracts/child/ChildToken/UpgradeableChildERC20/ERC20.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.6.0;





/**
 * Modified openzeppelin implemtation to add setters for name, symbol and decimals.
 * This was needed because the variables cannot be set in constructor as the contract is upgradeable.
 */

/**
 * @dev openzeppelin Implementation of the {IERC20} interface.
 *
 * Modified to add setters for name, symbol and decimals. This was needed
 * because
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20 {
    using SafeMath for uint256;
    using Address for address;

    mapping (address => uint256) private _balances;

    mapping (address => mapping (address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;
    uint8 private _decimals;

    /**
     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
     * a default value of 18.
     *
     * To select a different value for {decimals}, use {_setupDecimals}.
     *
     * All three of these values are immutable: they can only be set once during
     * construction.
     */
    constructor (string memory name, string memory symbol) public {
        _name = name;
        _symbol = symbol;
        _decimals = 18;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view returns (string memory) {
        return _name;
    }

    function setName(string memory newName) internal {
      _name = newName;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view returns (string memory) {
        return _symbol;
    }

    function setSymbol(string memory newSymbol) internal {
      _symbol = newSymbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5,05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
     * called.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view returns (uint8) {
        return _decimals;
    }

    function setDecimals(uint8 newDecimals) internal {
      _decimals = newDecimals;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view override returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20};
     *
     * Requirements:
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for ``sender``'s tokens of at least
     * `amount`.
     */
    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }

    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(address sender, address recipient, uint256 amount) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(sender, recipient, amount);

        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements
     *
     * - `to` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
     *
     * This is internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Sets {decimals} to a value other than the default one of 18.
     *
     * WARNING: This function should only be called from the constructor. Most
     * applications that interact with token contracts will not expect
     * {decimals} to ever change, and may work incorrectly if it does.
     */
    function _setupDecimals(uint8 decimals_) internal {
        _decimals = decimals_;
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be to transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
}

// File: @openzeppelin/contracts/utils/EnumerableSet.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.6.0;

/**
 * @dev Library for managing
 * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
 * types.
 *
 * Sets have the following properties:
 *
 * - Elements are added, removed, and checked for existence in constant time
 * (O(1)).
 * - Elements are enumerated in O(n). No guarantees are made on the ordering.
 *
 * ```
 * contract Example {
 *     // Add the library methods
 *     using EnumerableSet for EnumerableSet.AddressSet;
 *
 *     // Declare a set state variable
 *     EnumerableSet.AddressSet private mySet;
 * }
 * ```
 *
 * As of v3.0.0, only sets of type `address` (`AddressSet`) and `uint256`
 * (`UintSet`) are supported.
 */
library EnumerableSet {
    // To implement this library for multiple types with as little code
    // repetition as possible, we write it in terms of a generic Set type with
    // bytes32 values.
    // The Set implementation uses private functions, and user-facing
    // implementations (such as AddressSet) are just wrappers around the
    // underlying Set.
    // This means that we can only create new EnumerableSets for types that fit
    // in bytes32.

    struct Set {
        // Storage of set values
        bytes32[] _values;

        // Position of the value in the `values` array, plus 1 because index 0
        // means a value is not in the set.
        mapping (bytes32 => uint256) _indexes;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function _add(Set storage set, bytes32 value) private returns (bool) {
        if (!_contains(set, value)) {
            set._values.push(value);
            // The value is stored at length-1, but we add 1 to all indexes
            // and use 0 as a sentinel value
            set._indexes[value] = set._values.length;
            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function _remove(Set storage set, bytes32 value) private returns (bool) {
        // We read and store the value's index to prevent multiple reads from the same storage slot
        uint256 valueIndex = set._indexes[value];

        if (valueIndex != 0) { // Equivalent to contains(set, value)
            // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
            // the array, and then remove the last element (sometimes called as 'swap and pop').
            // This modifies the order of the array, as noted in {at}.

            uint256 toDeleteIndex = valueIndex - 1;
            uint256 lastIndex = set._values.length - 1;

            // When the value to delete is the last one, the swap operation is unnecessary. However, since this occurs
            // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.

            bytes32 lastvalue = set._values[lastIndex];

            // Move the last value to the index where the value to delete is
            set._values[toDeleteIndex] = lastvalue;
            // Update the index for the moved value
            set._indexes[lastvalue] = toDeleteIndex + 1; // All indexes are 1-based

            // Delete the slot where the moved value was stored
            set._values.pop();

            // Delete the index for the deleted slot
            delete set._indexes[value];

            return true;
        } else {
            return false;
        }
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function _contains(Set storage set, bytes32 value) private view returns (bool) {
        return set._indexes[value] != 0;
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function _length(Set storage set) private view returns (uint256) {
        return set._values.length;
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function _at(Set storage set, uint256 index) private view returns (bytes32) {
        require(set._values.length > index, "EnumerableSet: index out of bounds");
        return set._values[index];
    }

    // AddressSet

    struct AddressSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(AddressSet storage set, address value) internal returns (bool) {
        return _add(set._inner, bytes32(uint256(value)));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(AddressSet storage set, address value) internal returns (bool) {
        return _remove(set._inner, bytes32(uint256(value)));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(AddressSet storage set, address value) internal view returns (bool) {
        return _contains(set._inner, bytes32(uint256(value)));
    }

    /**
     * @dev Returns the number of values in the set. O(1).
     */
    function length(AddressSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(AddressSet storage set, uint256 index) internal view returns (address) {
        return address(uint256(_at(set._inner, index)));
    }


    // UintSet

    struct UintSet {
        Set _inner;
    }

    /**
     * @dev Add a value to a set. O(1).
     *
     * Returns true if the value was added to the set, that is if it was not
     * already present.
     */
    function add(UintSet storage set, uint256 value) internal returns (bool) {
        return _add(set._inner, bytes32(value));
    }

    /**
     * @dev Removes a value from a set. O(1).
     *
     * Returns true if the value was removed from the set, that is if it was
     * present.
     */
    function remove(UintSet storage set, uint256 value) internal returns (bool) {
        return _remove(set._inner, bytes32(value));
    }

    /**
     * @dev Returns true if the value is in the set. O(1).
     */
    function contains(UintSet storage set, uint256 value) internal view returns (bool) {
        return _contains(set._inner, bytes32(value));
    }

    /**
     * @dev Returns the number of values on the set. O(1).
     */
    function length(UintSet storage set) internal view returns (uint256) {
        return _length(set._inner);
    }

   /**
    * @dev Returns the value stored at position `index` in the set. O(1).
    *
    * Note that there are no guarantees on the ordering of values inside the
    * array, and it may change when more values are added or removed.
    *
    * Requirements:
    *
    * - `index` must be strictly less than {length}.
    */
    function at(UintSet storage set, uint256 index) internal view returns (uint256) {
        return uint256(_at(set._inner, index));
    }
}

// File: @openzeppelin/contracts/access/AccessControl.sol

// SPDX-License-Identifier: MIT

pragma solidity ^0.6.0;




/**
 * @dev Contract module that allows children to implement role-based access
 * control mechanisms.
 *
 * Roles are referred to by their `bytes32` identifier. These should be exposed
 * in the external API and be unique. The best way to achieve this is by
 * using `public constant` hash digests:
 *
 * ```
 * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
 * ```
 *
 * Roles can be used to represent a set of permissions. To restrict access to a
 * function call, use {hasRole}:
 *
 * ```
 * function foo() public {
 *     require(hasRole(MY_ROLE, msg.sender));
 *     ...
 * }
 * ```
 *
 * Roles can be granted and revoked dynamically via the {grantRole} and
 * {revokeRole} functions. Each role has an associated admin role, and only
 * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
 *
 * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
 * that only accounts with this role will be able to grant or revoke other
 * roles. More complex role relationships can be created by using
 * {_setRoleAdmin}.
 *
 * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
 * grant and revoke this role. Extra precautions should be taken to secure
 * accounts that have been granted it.
 */
abstract contract AccessControl is Context {
    using EnumerableSet for EnumerableSet.AddressSet;
    using Address for address;

    struct RoleData {
        EnumerableSet.AddressSet members;
        bytes32 adminRole;
    }

    mapping (bytes32 => RoleData) private _roles;

    bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;

    /**
     * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
     *
     * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
     * {RoleAdminChanged} not being emitted signaling this.
     *
     * _Available since v3.1._
     */
    event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);

    /**
     * @dev Emitted when `account` is granted `role`.
     *
     * `sender` is the account that originated the contract call, an admin role
     * bearer except when using {_setupRole}.
     */
    event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Emitted when `account` is revoked `role`.
     *
     * `sender` is the account that originated the contract call:
     *   - if using `revokeRole`, it is the admin role bearer
     *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
     */
    event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);

    /**
     * @dev Returns `true` if `account` has been granted `role`.
     */
    function hasRole(bytes32 role, address account) public view returns (bool) {
        return _roles[role].members.contains(account);
    }

    /**
     * @dev Returns the number of accounts that have `role`. Can be used
     * together with {getRoleMember} to enumerate all bearers of a role.
     */
    function getRoleMemberCount(bytes32 role) public view returns (uint256) {
        return _roles[role].members.length();
    }

    /**
     * @dev Returns one of the accounts that have `role`. `index` must be a
     * value between 0 and {getRoleMemberCount}, non-inclusive.
     *
     * Role bearers are not sorted in any particular way, and their ordering may
     * change at any point.
     *
     * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
     * you perform all queries on the same block. See the following
     * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]
     * for more information.
     */
    function getRoleMember(bytes32 role, uint256 index) public view returns (address) {
        return _roles[role].members.at(index);
    }

    /**
     * @dev Returns the admin role that controls `role`. See {grantRole} and
     * {revokeRole}.
     *
     * To change a role's admin, use {_setRoleAdmin}.
     */
    function getRoleAdmin(bytes32 role) public view returns (bytes32) {
        return _roles[role].adminRole;
    }

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function grantRole(bytes32 role, address account) public virtual {
        require(hasRole(_roles[role].adminRole, _msgSender()), "AccessControl: sender must be an admin to grant");

        _grantRole(role, account);
    }

    /**
     * @dev Revokes `role` from `account`.
     *
     * If `account` had been granted `role`, emits a {RoleRevoked} event.
     *
     * Requirements:
     *
     * - the caller must have ``role``'s admin role.
     */
    function revokeRole(bytes32 role, address account) public virtual {
        require(hasRole(_roles[role].adminRole, _msgSender()), "AccessControl: sender must be an admin to revoke");

        _revokeRole(role, account);
    }

    /**
     * @dev Revokes `role` from the calling account.
     *
     * Roles are often managed via {grantRole} and {revokeRole}: this function's
     * purpose is to provide a mechanism for accounts to lose their privileges
     * if they are compromised (such as when a trusted device is misplaced).
     *
     * If the calling account had been granted `role`, emits a {RoleRevoked}
     * event.
     *
     * Requirements:
     *
     * - the caller must be `account`.
     */
    function renounceRole(bytes32 role, address account) public virtual {
        require(account == _msgSender(), "AccessControl: can only renounce roles for self");

        _revokeRole(role, account);
    }

    /**
     * @dev Grants `role` to `account`.
     *
     * If `account` had not been already granted `role`, emits a {RoleGranted}
     * event. Note that unlike {grantRole}, this function doesn't perform any
     * checks on the calling account.
     *
     * [WARNING]
     * ====
     * This function should only be called from the constructor when setting
     * up the initial roles for the system.
     *
     * Using this function in any other way is effectively circumventing the admin
     * system imposed by {AccessControl}.
     * ====
     */
    function _setupRole(bytes32 role, address account) internal virtual {
        _grantRole(role, account);
    }

    /**
     * @dev Sets `adminRole` as ``role``'s admin role.
     *
     * Emits a {RoleAdminChanged} event.
     */
    function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
        emit RoleAdminChanged(role, _roles[role].adminRole, adminRole);
        _roles[role].adminRole = adminRole;
    }

    function _grantRole(bytes32 role, address account) private {
        if (_roles[role].members.add(account)) {
            emit RoleGranted(role, account, _msgSender());
        }
    }

    function _revokeRole(bytes32 role, address account) private {
        if (_roles[role].members.remove(account)) {
            emit RoleRevoked(role, account, _msgSender());
        }
    }
}

// File: contracts/common/AccessControlMixin.sol

pragma solidity 0.6.6;


contract AccessControlMixin is AccessControl {
    string private _revertMsg;
    function _setupContractId(string memory contractId) internal {
        _revertMsg = string(abi.encodePacked(contractId, ": INSUFFICIENT_PERMISSIONS"));
    }

    modifier only(bytes32 role) {
        require(
            hasRole(role, _msgSender()),
            _revertMsg
        );
        _;
    }
}

// File: contracts/child/ChildToken/IChildToken.sol

pragma solidity 0.6.6;

interface IChildToken {
    function deposit(address user, bytes calldata depositData) external;
}

// File: contracts/common/Initializable.sol

pragma solidity 0.6.6;

contract Initializable {
    bool inited = false;

    modifier initializer() {
        require(!inited, "already inited");
        _;
        inited = true;
    }
}

// File: contracts/common/EIP712Base.sol

pragma solidity 0.6.6;


contract EIP712Base is Initializable {
    struct EIP712Domain {
        string name;
        string version;
        address verifyingContract;
        bytes32 salt;
    }

    bytes32 internal constant EIP712_DOMAIN_TYPEHASH = keccak256(
        bytes(
            "EIP712Domain(string name,string version,address verifyingContract,bytes32 salt)"
        )
    );
    bytes32 internal domainSeperator;

    // supposed to be called once while initializing.
    // one of the contractsa that inherits this contract follows proxy pattern
    // so it is not possible to do this in a constructor
    function _initializeEIP712(
        string memory name,
        string memory version
    )
        internal
        initializer
    {
        _setDomainSeperator(name, version);
    }

    function _setDomainSeperator(string memory name, string memory version) internal {
        domainSeperator = keccak256(
            abi.encode(
                EIP712_DOMAIN_TYPEHASH,
                keccak256(bytes(name)),
                keccak256(bytes(version)),
                address(this),
                bytes32(getChainId())
            )
        );
    }

    function getDomainSeperator() public view returns (bytes32) {
        return domainSeperator;
    }

    function getChainId() public pure returns (uint256) {
        uint256 id;
        assembly {
            id := chainid()
        }
        return id;
    }

    /**
     * Accept message hash and returns hash message in EIP712 compatible form
     * So that it can be used to recover signer from signature signed using EIP712 formatted data
     * https://eips.ethereum.org/EIPS/eip-712
     * "\\x19" makes the encoding deterministic
     * "\\x01" is the version byte to make it compatible to EIP-191
     */
    function toTypedMessageHash(bytes32 messageHash)
        internal
        view
        returns (bytes32)
    {
        return
            keccak256(
                abi.encodePacked("\x19\x01", getDomainSeperator(), messageHash)
            );
    }
}

// File: contracts/common/NativeMetaTransaction.sol

pragma solidity 0.6.6;



contract NativeMetaTransaction is EIP712Base {
    using SafeMath for uint256;
    bytes32 private constant META_TRANSACTION_TYPEHASH = keccak256(
        bytes(
            "MetaTransaction(uint256 nonce,address from,bytes functionSignature)"
        )
    );
    event MetaTransactionExecuted(
        address userAddress,
        address payable relayerAddress,
        bytes functionSignature
    );
    mapping(address => uint256) nonces;

    /*
     * Meta transaction structure.
     * No point of including value field here as if user is doing value transfer then he has the funds to pay for gas
     * He should call the desired function directly in that case.
     */
    struct MetaTransaction {
        uint256 nonce;
        address from;
        bytes functionSignature;
    }

    function executeMetaTransaction(
        address userAddress,
        bytes memory functionSignature,
        bytes32 sigR,
        bytes32 sigS,
        uint8 sigV
    ) public payable returns (bytes memory) {
        MetaTransaction memory metaTx = MetaTransaction({
            nonce: nonces[userAddress],
            from: userAddress,
            functionSignature: functionSignature
        });

        require(
            verify(userAddress, metaTx, sigR, sigS, sigV),
            "Signer and signature do not match"
        );

        // increase nonce for user (to avoid re-use)
        nonces[userAddress] = nonces[userAddress].add(1);

        emit MetaTransactionExecuted(
            userAddress,
            msg.sender,
            functionSignature
        );

        // Append userAddress and relayer address at the end to extract it from calling context
        (bool success, bytes memory returnData) = address(this).call(
            abi.encodePacked(functionSignature, userAddress)
        );
        require(success, "Function call not successful");

        return returnData;
    }

    function hashMetaTransaction(MetaTransaction memory metaTx)
        internal
        pure
        returns (bytes32)
    {
        return
            keccak256(
                abi.encode(
                    META_TRANSACTION_TYPEHASH,
                    metaTx.nonce,
                    metaTx.from,
                    keccak256(metaTx.functionSignature)
                )
            );
    }

    function getNonce(address user) public view returns (uint256 nonce) {
        nonce = nonces[user];
    }

    function verify(
        address signer,
        MetaTransaction memory metaTx,
        bytes32 sigR,
        bytes32 sigS,
        uint8 sigV
    ) internal view returns (bool) {
        require(signer != address(0), "NativeMetaTransaction: INVALID_SIGNER");
        return
            signer ==
            ecrecover(
                toTypedMessageHash(hashMetaTransaction(metaTx)),
                sigV,
                sigR,
                sigS
            );
    }
}

// File: contracts/ChainConstants.sol

pragma solidity 0.6.6;

contract ChainConstants {
    string constant public ERC712_VERSION = "1";

    uint256 constant public ROOT_CHAIN_ID = 1;
    bytes constant public ROOT_CHAIN_ID_BYTES = hex"01";

    uint256 constant public CHILD_CHAIN_ID = 137;
    bytes constant public CHILD_CHAIN_ID_BYTES = hex"89";
}

// File: contracts/common/ContextMixin.sol

pragma solidity 0.6.6;

abstract contract ContextMixin {
    function msgSender()
        internal
        view
        returns (address payable sender)
    {
        if (msg.sender == address(this)) {
            bytes memory array = msg.data;
            uint256 index = msg.data.length;
            assembly {
                // Load the 32 bytes word from memory with the address on the lower 20 bytes, and mask those.
                sender := and(
                    mload(add(array, index)),
                    0xffffffffffffffffffffffffffffffffffffffff
                )
            }
        } else {
            sender = msg.sender;
        }
        return sender;
    }
}

// File: contracts/child/ChildToken/UpgradeableChildERC20/UChildERC20.sol

pragma solidity 0.6.6;








contract UChildERC20 is
    ERC20,
    IChildToken,
    AccessControlMixin,
    NativeMetaTransaction,
    ChainConstants,
    ContextMixin
{
    bytes32 public constant DEPOSITOR_ROLE = keccak256("DEPOSITOR_ROLE");

    constructor() public ERC20("", "") {}

    /**
     * @notice Initialize the contract after it has been proxified
     * @dev meant to be called once immediately after deployment
     */
    function initialize(
        string calldata name_,
        string calldata symbol_,
        uint8 decimals_,
        address childChainManager
    )
        external
        initializer
    {
      setName(name_);
      setSymbol(symbol_);
      setDecimals(decimals_);
      _setupContractId(string(abi.encodePacked("Child", symbol_)));
      _setupRole(DEFAULT_ADMIN_ROLE, _msgSender());
      _setupRole(DEPOSITOR_ROLE, childChainManager);
      _initializeEIP712(name_, ERC712_VERSION);
    }

    // This is to support Native meta transactions
    // never use msg.sender directly, use _msgSender() instead
    function _msgSender()
        internal
        override
        view
        returns (address payable sender)
    {
        return ContextMixin.msgSender();
    }

    function changeName(string calldata name_) external only(DEFAULT_ADMIN_ROLE) {
        setName(name_);
        _setDomainSeperator(name_, ERC712_VERSION);
    }

    /**
     * @notice called when token is deposited on root chain
     * @dev Should be callable only by ChildChainManager
     * Should handle deposit by minting the required amount for user
     * Make sure minting is done only by this function
     * @param user user address for whom deposit is being done
     * @param depositData abi encoded amount
     */
    function deposit(address user, bytes calldata depositData)
        external
        override
        only(DEPOSITOR_ROLE)
    {
        uint256 amount = abi.decode(depositData, (uint256));
        _mint(user, amount);
    }

    /**
     * @notice called when user wants to withdraw tokens back to root chain
     * @dev Should burn user's tokens. This transaction will be verified when exiting on root chain
     * @param amount amount of tokens to withdraw
     */
    function withdraw(uint256 amount) external {
        _burn(_msgSender(), amount);
    }
}

Contract Security Audit

Contract ABI

[{"inputs":[],"stateMutability":"nonpayable","type":"constructor"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"owner","type":"address"},{"indexed":true,"internalType":"address","name":"spender","type":"address"},{"indexed":false,"internalType":"uint256","name":"value","type":"uint256"}],"name":"Approval","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"address","name":"userAddress","type":"address"},{"indexed":false,"internalType":"address payable","name":"relayerAddress","type":"address"},{"indexed":false,"internalType":"bytes","name":"functionSignature","type":"bytes"}],"name":"MetaTransactionExecuted","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"bytes32","name":"role","type":"bytes32"},{"indexed":true,"internalType":"bytes32","name":"previousAdminRole","type":"bytes32"},{"indexed":true,"internalType":"bytes32","name":"newAdminRole","type":"bytes32"}],"name":"RoleAdminChanged","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"bytes32","name":"role","type":"bytes32"},{"indexed":true,"internalType":"address","name":"account","type":"address"},{"indexed":true,"internalType":"address","name":"sender","type":"address"}],"name":"RoleGranted","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"bytes32","name":"role","type":"bytes32"},{"indexed":true,"internalType":"address","name":"account","type":"address"},{"indexed":true,"internalType":"address","name":"sender","type":"address"}],"name":"RoleRevoked","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"from","type":"address"},{"indexed":true,"internalType":"address","name":"to","type":"address"},{"indexed":false,"internalType":"uint256","name":"value","type":"uint256"}],"name":"Transfer","type":"event"},{"inputs":[],"name":"CHILD_CHAIN_ID","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"CHILD_CHAIN_ID_BYTES","outputs":[{"internalType":"bytes","name":"","type":"bytes"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"DEFAULT_ADMIN_ROLE","outputs":[{"internalType":"bytes32","name":"","type":"bytes32"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"DEPOSITOR_ROLE","outputs":[{"internalType":"bytes32","name":"","type":"bytes32"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"ERC712_VERSION","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"ROOT_CHAIN_ID","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"ROOT_CHAIN_ID_BYTES","outputs":[{"internalType":"bytes","name":"","type":"bytes"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"owner","type":"address"},{"internalType":"address","name":"spender","type":"address"}],"name":"allowance","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"spender","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"}],"name":"approve","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"account","type":"address"}],"name":"balanceOf","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"string","name":"name_","type":"string"}],"name":"changeName","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"decimals","outputs":[{"internalType":"uint8","name":"","type":"uint8"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"spender","type":"address"},{"internalType":"uint256","name":"subtractedValue","type":"uint256"}],"name":"decreaseAllowance","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"user","type":"address"},{"internalType":"bytes","name":"depositData","type":"bytes"}],"name":"deposit","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"userAddress","type":"address"},{"internalType":"bytes","name":"functionSignature","type":"bytes"},{"internalType":"bytes32","name":"sigR","type":"bytes32"},{"internalType":"bytes32","name":"sigS","type":"bytes32"},{"internalType":"uint8","name":"sigV","type":"uint8"}],"name":"executeMetaTransaction","outputs":[{"internalType":"bytes","name":"","type":"bytes"}],"stateMutability":"payable","type":"function"},{"inputs":[],"name":"getChainId","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"pure","type":"function"},{"inputs":[],"name":"getDomainSeperator","outputs":[{"internalType":"bytes32","name":"","type":"bytes32"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"user","type":"address"}],"name":"getNonce","outputs":[{"internalType":"uint256","name":"nonce","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"bytes32","name":"role","type":"bytes32"}],"name":"getRoleAdmin","outputs":[{"internalType":"bytes32","name":"","type":"bytes32"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"bytes32","name":"role","type":"bytes32"},{"internalType":"uint256","name":"index","type":"uint256"}],"name":"getRoleMember","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"bytes32","name":"role","type":"bytes32"}],"name":"getRoleMemberCount","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"bytes32","name":"role","type":"bytes32"},{"internalType":"address","name":"account","type":"address"}],"name":"grantRole","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"bytes32","name":"role","type":"bytes32"},{"internalType":"address","name":"account","type":"address"}],"name":"hasRole","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"spender","type":"address"},{"internalType":"uint256","name":"addedValue","type":"uint256"}],"name":"increaseAllowance","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"string","name":"name_","type":"string"},{"internalType":"string","name":"symbol_","type":"string"},{"internalType":"uint8","name":"decimals_","type":"uint8"},{"internalType":"address","name":"childChainManager","type":"address"}],"name":"initialize","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"name","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"bytes32","name":"role","type":"bytes32"},{"internalType":"address","name":"account","type":"address"}],"name":"renounceRole","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"bytes32","name":"role","type":"bytes32"},{"internalType":"address","name":"account","type":"address"}],"name":"revokeRole","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"symbol","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"totalSupply","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"recipient","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"}],"name":"transfer","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"sender","type":"address"},{"internalType":"address","name":"recipient","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"}],"name":"transferFrom","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"amount","type":"uint256"}],"name":"withdraw","outputs":[],"stateMutability":"nonpayable","type":"function"}]

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

Block Transaction Gas Used Reward
Age Block Fee Address BC Fee Address Voting Power Jailed Incoming
Block Uncle Number Difficulty Gas Used Reward
Loading
Loading
Make sure to use the "Vote Down" button for any spammy posts, and the "Vote Up" for interesting conversations.