// SPDX-License-Identifier: Apache-2.0
// Copyright 2017 Loopring Technology Limited.
pragma solidity ^0.7.0;


/// @title Ownable
/// @author Brecht Devos - <brecht@loopring.org>
/// @dev The Ownable contract has an owner address, and provides basic
///      authorization control functions, this simplifies the implementation of
///      "user permissions".
contract Ownable
{
    address public owner;

    event OwnershipTransferred(
        address indexed previousOwner,
        address indexed newOwner
    );

    /// @dev The Ownable constructor sets the original `owner` of the contract
    ///      to the sender.
    constructor()
    {
        owner = msg.sender;
    }

    /// @dev Throws if called by any account other than the owner.
    modifier onlyOwner()
    {
        require(msg.sender == owner, "UNAUTHORIZED");
        _;
    }

    /// @dev Allows the current owner to transfer control of the contract to a
    ///      new owner.
    /// @param newOwner The address to transfer ownership to.
    function transferOwnership(
        address newOwner
        )
        public
        virtual
        onlyOwner
    {
        require(newOwner != address(0), "ZERO_ADDRESS");
        emit OwnershipTransferred(owner, newOwner);
        owner = newOwner;
    }

    function renounceOwnership()
        public
        onlyOwner
    {
        emit OwnershipTransferred(owner, address(0));
        owner = address(0);
    }
}

// Copyright 2017 Loopring Technology Limited.



/// @title AddressSet
/// @author Daniel Wang - <daniel@loopring.org>
contract AddressSet
{
    struct Set
    {
        address[] addresses;
        mapping (address => uint) positions;
        uint count;
    }
    mapping (bytes32 => Set) private sets;

    function addAddressToSet(
        bytes32 key,
        address addr,
        bool    maintainList
        ) internal
    {
        Set storage set = sets[key];
        require(set.positions[addr] == 0, "ALREADY_IN_SET");

        if (maintainList) {
            require(set.addresses.length == set.count, "PREVIOUSLY_NOT_MAINTAILED");
            set.addresses.push(addr);
        } else {
            require(set.addresses.length == 0, "MUST_MAINTAIN");
        }

        set.count += 1;
        set.positions[addr] = set.count;
    }

    function removeAddressFromSet(
        bytes32 key,
        address addr
        )
        internal
    {
        Set storage set = sets[key];
        uint pos = set.positions[addr];
        require(pos != 0, "NOT_IN_SET");

        delete set.positions[addr];
        set.count -= 1;

        if (set.addresses.length > 0) {
            address lastAddr = set.addresses[set.count];
            if (lastAddr != addr) {
                set.addresses[pos - 1] = lastAddr;
                set.positions[lastAddr] = pos;
            }
            set.addresses.pop();
        }
    }

    function removeSet(bytes32 key)
        internal
    {
        delete sets[key];
    }

    function isAddressInSet(
        bytes32 key,
        address addr
        )
        internal
        view
        returns (bool)
    {
        return sets[key].positions[addr] != 0;
    }

    function numAddressesInSet(bytes32 key)
        internal
        view
        returns (uint)
    {
        Set storage set = sets[key];
        return set.count;
    }

    function addressesInSet(bytes32 key)
        internal
        view
        returns (address[] memory)
    {
        Set storage set = sets[key];
        require(set.count == set.addresses.length, "NOT_MAINTAINED");
        return sets[key].addresses;
    }
}
// Copyright 2017 Loopring Technology Limited.



/// @title Utility Functions for uint
/// @author Daniel Wang - <daniel@loopring.org>
library MathUint
{
    function mul(
        uint a,
        uint b
        )
        internal
        pure
        returns (uint c)
    {
        c = a * b;
        require(a == 0 || c / a == b, "MUL_OVERFLOW");
    }

    function sub(
        uint a,
        uint b
        )
        internal
        pure
        returns (uint)
    {
        require(b <= a, "SUB_UNDERFLOW");
        return a - b;
    }

    function add(
        uint a,
        uint b
        )
        internal
        pure
        returns (uint c)
    {
        c = a + b;
        require(c >= a, "ADD_OVERFLOW");
    }
}

//Mainly taken from https://github.com/GNSPS/solidity-bytes-utils/blob/master/contracts/BytesLib.sol


library BytesUtil {
    function slice(
        bytes memory _bytes,
        uint _start,
        uint _length
    )
        internal
        pure
        returns (bytes memory)
    {
        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 memory _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 memory _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 memory _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 toUint24(bytes memory _bytes, uint _start) internal  pure returns (uint24) {
        require(_bytes.length >= (_start + 3));
        uint24 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x3), _start))
        }

        return tempUint;
    }

    function toUint32(bytes memory _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 toUint64(bytes memory _bytes, uint _start) internal  pure returns (uint64) {
        require(_bytes.length >= (_start + 8));
        uint64 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x8), _start))
        }

        return tempUint;
    }

    function toUint96(bytes memory _bytes, uint _start) internal  pure returns (uint96) {
        require(_bytes.length >= (_start + 12));
        uint96 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0xc), _start))
        }

        return tempUint;
    }

    function toUint128(bytes memory _bytes, uint _start) internal  pure returns (uint128) {
        require(_bytes.length >= (_start + 16));
        uint128 tempUint;

        assembly {
            tempUint := mload(add(add(_bytes, 0x10), _start))
        }

        return tempUint;
    }

    function toUint(bytes memory _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 toBytes4(bytes memory _bytes, uint _start) internal  pure returns (bytes4) {
        require(_bytes.length >= (_start + 4));
        bytes4 tempBytes4;

        assembly {
            tempBytes4 := mload(add(add(_bytes, 0x20), _start))
        }

        return tempBytes4;
    }

    function toBytes32(bytes memory _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 fastSHA256(
        bytes memory data
        )
        internal
        view
        returns (bytes32)
    {
        bytes32[] memory result = new bytes32[](1);
        bool success;
        assembly {
             let ptr := add(data, 32)
             success := staticcall(sub(gas(), 2000), 2, ptr, mload(data), add(result, 32), 32)
        }
        require(success, "SHA256_FAILED");
        return result[0];
    }
}

// Copyright 2017 Loopring Technology Limited.

pragma experimental ABIEncoderV2;



// Copyright 2017 Loopring Technology Limited.



/// @title Utility Functions for addresses
/// @author Daniel Wang - <daniel@loopring.org>
/// @author Brecht Devos - <brecht@loopring.org>
library AddressUtil
{
    using AddressUtil for *;

    function isContract(
        address addr
        )
        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;
        // solhint-disable-next-line no-inline-assembly
        assembly { codehash := extcodehash(addr) }
        return (codehash != 0x0 &&
                codehash != 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470);
    }

    function toPayable(
        address addr
        )
        internal
        pure
        returns (address payable)
    {
        return address(uint160(addr));
    }

    // Works like address.send but with a customizable gas limit
    // Make sure your code is safe for reentrancy when using this function!
    function sendETH(
        address to,
        uint    amount,
        uint    gasLimit
        )
        internal
        returns (bool success)
    {
        if (amount == 0) {
            return true;
        }
        address payable recipient = to.toPayable();
        /* solium-disable-next-line */
        (success,) = recipient.call{value: amount, gas: gasLimit}("");
    }

    // Works like address.transfer but with a customizable gas limit
    // Make sure your code is safe for reentrancy when using this function!
    function sendETHAndVerify(
        address to,
        uint    amount,
        uint    gasLimit
        )
        internal
        returns (bool success)
    {
        success = to.sendETH(amount, gasLimit);
        require(success, "TRANSFER_FAILURE");
    }
}




/// @title SignatureUtil
/// @author Daniel Wang - <daniel@loopring.org>
/// @dev This method supports multihash standard. Each signature's first byte indicates
///      the signature's type, the second byte indicates the signature's length, therefore,
///      each signature will have 2 extra bytes prefix. Mulitple signatures are concatenated
///      together.
library SignatureUtil
{
    using BytesUtil     for bytes;
    using MathUint      for uint;
    using AddressUtil   for address;

    enum SignatureType {
        ILLEGAL,
        INVALID,
        EIP_712,
        ETH_SIGN,
        WALLET   // deprecated
    }

    bytes4 constant internal ERC1271_MAGICVALUE = 0x20c13b0b;

    bytes4 constant internal ERC1271_FUNCTION_WITH_BYTES_SELECTOR = bytes4(
        keccak256(bytes("isValidSignature(bytes,bytes)"))
    );

    bytes4 constant internal ERC1271_FUNCTION_WITH_BYTES32_SELECTOR = bytes4(
        keccak256(bytes("isValidSignature(bytes32,bytes)"))
    );

    function verifySignatures(
        bytes32          signHash,
        address[] memory signers,
        bytes[]   memory signatures
        )
        internal
        view
        returns (bool)
    {
        return verifySignatures(abi.encodePacked(signHash), signers, signatures);
    }

    function verifySignatures(
        bytes     memory data,
        address[] memory signers,
        bytes[]   memory signatures
        )
        internal
        view
        returns (bool)
    {
        require(signers.length == signatures.length, "BAD_SIGNATURE_DATA");
        address lastSigner;
        for (uint i = 0; i < signers.length; i++) {
            require(signers[i] > lastSigner, "INVALID_SIGNERS_ORDER");
            lastSigner = signers[i];
            if (!verifySignature(data, signers[i], signatures[i])) {
                return false;
            }
        }
        return true;
    }

    function verifySignature(
        bytes   memory data,
        address        signer,
        bytes   memory signature
        )
        internal
        view
        returns (bool)
    {
        return signer.isContract() ?
            verifyERC1271Signature(data, signer, signature) :
            verifyEOASignature(data, signer, signature);
    }

    function verifySignature(
        bytes32        signHash,
        address        signer,
        bytes   memory signature
        )
        internal
        view
        returns (bool)
    {
        return verifySignature(abi.encodePacked(signHash), signer, signature);
    }

    function recoverECDSASigner(
        bytes32      signHash,
        bytes memory signature
        )
        internal
        pure
        returns (address)
    {
        if (signature.length != 65) {
            return address(0);
        }

        bytes32 r;
        bytes32 s;
        uint8   v;
        // we jump 32 (0x20) as the first slot of bytes contains the length
        // we jump 65 (0x41) per signature
        // for v we load 32 bytes ending with v (the first 31 come from s) then apply a mask
        assembly {
            r := mload(add(signature, 0x20))
            s := mload(add(signature, 0x40))
            v := and(mload(add(signature, 0x41)), 0xff)
        }
        // See https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/cryptography/ECDSA.sol
        if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
            return address(0);
        }
        if (v == 27 || v == 28) {
            return ecrecover(signHash, v, r, s);
        } else {
            return address(0);
        }
    }

    function recoverECDSASigner(
        bytes memory data,
        bytes memory signature
        )
        internal
        pure
        returns (address addr1, address addr2)
    {
        if (data.length == 32) {
            addr1 = recoverECDSASigner(data.toBytes32(0), signature);
        }
        addr2 = recoverECDSASigner(keccak256(data), signature);
    }

    function verifyEOASignature(
        bytes   memory data,
        address        signer,
        bytes   memory signature
        )
        private
        pure
        returns (bool)
    {
        if (signer == address(0)) {
            return false;
        }

        uint signatureTypeOffset = signature.length.sub(1);
        SignatureType signatureType = SignatureType(signature.toUint8(signatureTypeOffset));

        bytes memory stripped = signature.slice(0, signatureTypeOffset);

        if (signatureType == SignatureType.EIP_712) {
            (address addr1, address addr2) = recoverECDSASigner(data, stripped);
            return addr1 == signer || addr2 == signer;
        } else if (signatureType == SignatureType.ETH_SIGN) {
            if (data.length == 32) {
                bytes32 hash = keccak256(
                    abi.encodePacked("\x19Ethereum Signed Message:\n32", data.toBytes32(0))
                );
                if (recoverECDSASigner(hash, stripped) == signer) {
                    return true;
                }
            }
            bytes32 hash = keccak256(
                abi.encodePacked("\x19Ethereum Signed Message:\n32", keccak256(data))
            );
            return recoverECDSASigner(hash, stripped) == signer;
        } else {
            return false;
        }
    }

    function verifyERC1271Signature(
        bytes   memory data,
        address signer,
        bytes   memory signature
        )
        private
        view
        returns (bool)
    {
        return data.length == 32 &&
            verifyERC1271WithBytes32(data.toBytes32(0), signer, signature) ||
            verifyERC1271WithBytes(data, signer, signature);
    }

    function verifyERC1271WithBytes(
        bytes   memory data,
        address signer,
        bytes   memory signature
        )
        private
        view
        returns (bool)
    {
        bytes memory callData = abi.encodeWithSelector(
            ERC1271_FUNCTION_WITH_BYTES_SELECTOR,
            data,
            signature
        );
        (bool success, bytes memory result) = signer.staticcall(callData);
        return (
            success &&
            result.length == 32 &&
            result.toBytes4(0) == ERC1271_MAGICVALUE
        );
    }

    function verifyERC1271WithBytes32(
        bytes32 hash,
        address signer,
        bytes   memory signature
        )
        private
        view
        returns (bool)
    {
        bytes memory callData = abi.encodeWithSelector(
            ERC1271_FUNCTION_WITH_BYTES32_SELECTOR,
            hash,
            signature
        );
        (bool success, bytes memory result) = signer.staticcall(callData);
        return (
            success &&
            result.length == 32 &&
            result.toBytes4(0) == ERC1271_MAGICVALUE
        );
    }
}

// Copyright 2017 Loopring Technology Limited.



// Copyright 2017 Loopring Technology Limited.


abstract contract ERC1271 {
    // bytes4(keccak256("isValidSignature(bytes,bytes)")
    bytes4 constant internal ERC1271_MAGICVALUE = 0x20c13b0b;

    bytes4 constant internal ERC1271_FUNCTION_WITH_BYTES_SELECTOR = bytes4(
        keccak256(bytes("isValidSignature(bytes,bytes)"))
    );

    bytes4 constant internal ERC1271_FUNCTION_WITH_BYTES32_SELECTOR = bytes4(
        keccak256(bytes("isValidSignature(bytes32,bytes)"))
    );

    /**
     * @dev Should return whether the signature provided is valid for the provided data
     * @param _data Arbitrary length data signed on the behalf of address(this)
     * @param _signature Signature byte array associated with _data
     *
     * MUST return the bytes4 magic value 0x20c13b0b when function passes.
     * MUST NOT modify state (using STATICCALL for solc < 0.5, view modifier for solc > 0.5)
     * MUST allow external calls
     */
    function isValidSignature(
        bytes memory _data,
        bytes memory _signature)
        public
        view
        virtual
        returns (bytes4 magicValue);

    function isValidSignature(
        bytes32      _hash,
        bytes memory _signature)
        public
        view
        virtual
        returns (bytes4 magicValue)
    {
        return isValidSignature(abi.encodePacked(_hash), _signature);
    }
}

// Copyright 2017 Loopring Technology Limited.




// Copyright 2017 Loopring Technology Limited.





/// @title Claimable
/// @author Brecht Devos - <brecht@loopring.org>
/// @dev Extension for the Ownable contract, where the ownership needs
///      to be claimed. This allows the new owner to accept the transfer.
contract Claimable is Ownable
{
    address public pendingOwner;

    /// @dev Modifier throws if called by any account other than the pendingOwner.
    modifier onlyPendingOwner() {
        require(msg.sender == pendingOwner, "UNAUTHORIZED");
        _;
    }

    /// @dev Allows the current owner to set the pendingOwner address.
    /// @param newOwner The address to transfer ownership to.
    function transferOwnership(
        address newOwner
        )
        public
        override
        onlyOwner
    {
        require(newOwner != address(0) && newOwner != owner, "INVALID_ADDRESS");
        pendingOwner = newOwner;
    }

    /// @dev Allows the pendingOwner address to finalize the transfer.
    function claimOwnership()
        public
        onlyPendingOwner
    {
        emit OwnershipTransferred(owner, pendingOwner);
        owner = pendingOwner;
        pendingOwner = address(0);
    }
}



contract OwnerManagable is Claimable, AddressSet
{
    bytes32 internal constant MANAGER = keccak256("__MANAGED__");

    event ManagerAdded  (address manager);
    event ManagerRemoved(address manager);

    modifier onlyManager
    {
        require(isManager(msg.sender), "NOT_MANAGER");
        _;
    }

    modifier onlyOwnerOrManager
    {
        require(msg.sender == owner || isManager(msg.sender), "NOT_OWNER_OR_MANAGER");
        _;
    }

    constructor() Claimable() {}

    /// @dev Gets the managers.
    /// @return The list of managers.
    function managers()
        public
        view
        returns (address[] memory)
    {
        return addressesInSet(MANAGER);
    }

    /// @dev Gets the number of managers.
    /// @return The numer of managers.
    function numManagers()
        public
        view
        returns (uint)
    {
        return numAddressesInSet(MANAGER);
    }

    /// @dev Checks if an address is a manger.
    /// @param addr The address to check.
    /// @return True if the address is a manager, False otherwise.
    function isManager(address addr)
        public
        view
        returns (bool)
    {
        return isAddressInSet(MANAGER, addr);
    }

    /// @dev Adds a new manager.
    /// @param manager The new address to add.
    function addManager(address manager)
        public
        onlyOwner
    {
        addManagerInternal(manager);
    }

    /// @dev Removes a manager.
    /// @param manager The manager to remove.
    function removeManager(address manager)
        public
        onlyOwner
    {
        removeAddressFromSet(MANAGER, manager);
        emit ManagerRemoved(manager);
    }

    function addManagerInternal(address manager)
        internal
    {
        addAddressToSet(MANAGER, manager, true);
        emit ManagerAdded(manager);
    }
}




/// @title OfficialGuardian
/// @author Freeman Zhong - <kongliang@loopring.org>
contract OfficialGuardian is OwnerManagable, ERC1271
{
    using SignatureUtil for bytes;
    mapping (address => bool) public whitelist;

    function isValidSignature(
        bytes memory _data,
        bytes memory _signature
        )
        public
        view
        override
        returns (bytes4)
    {
        (address addr1, address addr2) = _data.recoverECDSASigner(_signature);
        return isManager(addr1) || isManager(addr2) ?  ERC1271_MAGICVALUE : bytes4(0);
    }

    function addWhitelist(address target, bool toAdd)
        external
        onlyOwner
    {
        require(target != address(0), "ZERO_ADDRESS");
        require(whitelist[target] != toAdd, "SAME_VALUE");
        whitelist[target] = toAdd;
    }

    function transact(
        address  target,
        uint     value,
        bytes    calldata data
        )
        external
        onlyManager
        returns (
            bool success,
            bytes memory returnData
        )
    {
        require(whitelist[target], "INVALID_TARGET");
        // solium-disable-next-line security/no-call-value
        (success, returnData) = target.call{value: value}(data);
    }
}