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0x56AcF08C6C6d64f2CDB01b9Ab7D35FA9a023662A

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Contract Source Code Verified (Exact Match)

Contract Name:
SwapExecutor

Compiler Version
v0.8.19+commit.7dd6d404

Optimization Enabled:
Yes with 200 runs

Other Settings:
default evmVersion
File 1 of 4 : SwapExecutor.sol
// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.17;
import {ERC20} from "solmate/src/tokens/ERC20.sol";
import {SafeTransferLib} from "solmate/src/utils/SafeTransferLib.sol";

import {IFeeCollector} from "../interfaces/IFeeCollector.sol";

contract SwapExecutor {
    using SafeTransferLib for ERC20;

    error TransferFailed();

    address public constant NATIVE_TOKEN_ADDRESS = 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;

    function executeSwap(address token, uint256 amount, address swapRouter, bytes memory swapPayload) external {
        ERC20(token).safeApprove(swapRouter, amount);

        (bool success, ) = swapRouter.call(swapPayload);
        if (!success) revert();
    }

    function executeSwapWithValue(address swapRouter, bytes memory swapPayload, uint256 msgValue) external {
        (bool success, ) = swapRouter.call{value: msgValue}(swapPayload);

        if (!success) revert();
    }

    function collectFeeAndExecuteSwap(
        address token,
        uint256 amount,
        address swapRouter,
        /// @notice swapPayload should consider (amount - feeAmount) as the swap input
        bytes memory swapPayload,
        IFeeCollector feeCollector,
        address feeTaker,
        uint256 feeAmount
    ) external {
        _collectFee(token, feeAmount, feeTaker, feeCollector);

        ERC20(token).safeApprove(swapRouter, amount - feeAmount);

        (bool success, ) = swapRouter.call(swapPayload);
        if (!success) revert();
    }

    // @todo should there be a function that takes requestHash and registers locked fee as well?

    /**
     * @dev collects unlocked fee in input token and registers it with the FeeCollector
     */
    function _collectFee(address token, uint256 amount, address feeTaker, IFeeCollector feeCollector) internal {
        _sendFundsFromContract(token, amount, address(feeCollector));
        feeCollector.registerFee(feeTaker, amount, token);
    }

    /**
     * @dev send funds to the provided address.
     * @param token address of the token
     * @param amount hash of the command.
     * @param to address, funds will be transferred to this address.
     */
    function _sendFundsFromContract(address token, uint256 amount, address to) internal {
        /// native token case
        if (token == NATIVE_TOKEN_ADDRESS) {
            (bool success, ) = to.call{value: amount, gas: 5000}("");
            if (!success) revert TransferFailed();
            return;
        }

        /// ERC20 case
        ERC20(token).safeTransfer(to, amount);
    }
}

File 2 of 4 : ERC20.sol
// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

/// @notice Modern and gas efficient ERC20 + EIP-2612 implementation.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC20.sol)
/// @author Modified from Uniswap (https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/UniswapV2ERC20.sol)
/// @dev Do not manually set balances without updating totalSupply, as the sum of all user balances must not exceed it.
abstract contract ERC20 {
    /*//////////////////////////////////////////////////////////////
                                 EVENTS
    //////////////////////////////////////////////////////////////*/

    event Transfer(address indexed from, address indexed to, uint256 amount);

    event Approval(address indexed owner, address indexed spender, uint256 amount);

    /*//////////////////////////////////////////////////////////////
                            METADATA STORAGE
    //////////////////////////////////////////////////////////////*/

    string public name;

    string public symbol;

    uint8 public immutable decimals;

    /*//////////////////////////////////////////////////////////////
                              ERC20 STORAGE
    //////////////////////////////////////////////////////////////*/

    uint256 public totalSupply;

    mapping(address => uint256) public balanceOf;

    mapping(address => mapping(address => uint256)) public allowance;

    /*//////////////////////////////////////////////////////////////
                            EIP-2612 STORAGE
    //////////////////////////////////////////////////////////////*/

    uint256 internal immutable INITIAL_CHAIN_ID;

    bytes32 internal immutable INITIAL_DOMAIN_SEPARATOR;

    mapping(address => uint256) public nonces;

    /*//////////////////////////////////////////////////////////////
                               CONSTRUCTOR
    //////////////////////////////////////////////////////////////*/

    constructor(string memory _name, string memory _symbol, uint8 _decimals) {
        name = _name;
        symbol = _symbol;
        decimals = _decimals;

        INITIAL_CHAIN_ID = block.chainid;
        INITIAL_DOMAIN_SEPARATOR = computeDomainSeparator();
    }

    /*//////////////////////////////////////////////////////////////
                               ERC20 LOGIC
    //////////////////////////////////////////////////////////////*/

    function approve(address spender, uint256 amount) public virtual returns (bool) {
        allowance[msg.sender][spender] = amount;

        emit Approval(msg.sender, spender, amount);

        return true;
    }

    function transfer(address to, uint256 amount) public virtual returns (bool) {
        balanceOf[msg.sender] -= amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(msg.sender, to, amount);

        return true;
    }

    function transferFrom(address from, address to, uint256 amount) public virtual returns (bool) {
        uint256 allowed = allowance[from][msg.sender]; // Saves gas for limited approvals.

        if (allowed != type(uint256).max) allowance[from][msg.sender] = allowed - amount;

        balanceOf[from] -= amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(from, to, amount);

        return true;
    }

    /*//////////////////////////////////////////////////////////////
                             EIP-2612 LOGIC
    //////////////////////////////////////////////////////////////*/

    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual {
        require(deadline >= block.timestamp, "PERMIT_DEADLINE_EXPIRED");

        // Unchecked because the only math done is incrementing
        // the owner's nonce which cannot realistically overflow.
        unchecked {
            address recoveredAddress = ecrecover(
                keccak256(
                    abi.encodePacked(
                        "\x19\x01",
                        DOMAIN_SEPARATOR(),
                        keccak256(
                            abi.encode(
                                keccak256(
                                    "Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
                                ),
                                owner,
                                spender,
                                value,
                                nonces[owner]++,
                                deadline
                            )
                        )
                    )
                ),
                v,
                r,
                s
            );

            require(recoveredAddress != address(0) && recoveredAddress == owner, "INVALID_SIGNER");

            allowance[recoveredAddress][spender] = value;
        }

        emit Approval(owner, spender, value);
    }

    function DOMAIN_SEPARATOR() public view virtual returns (bytes32) {
        return block.chainid == INITIAL_CHAIN_ID ? INITIAL_DOMAIN_SEPARATOR : computeDomainSeparator();
    }

    function computeDomainSeparator() internal view virtual returns (bytes32) {
        return
            keccak256(
                abi.encode(
                    keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
                    keccak256(bytes(name)),
                    keccak256("1"),
                    block.chainid,
                    address(this)
                )
            );
    }

    /*//////////////////////////////////////////////////////////////
                        INTERNAL MINT/BURN LOGIC
    //////////////////////////////////////////////////////////////*/

    function _mint(address to, uint256 amount) internal virtual {
        totalSupply += amount;

        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }

        emit Transfer(address(0), to, amount);
    }

    function _burn(address from, uint256 amount) internal virtual {
        balanceOf[from] -= amount;

        // Cannot underflow because a user's balance
        // will never be larger than the total supply.
        unchecked {
            totalSupply -= amount;
        }

        emit Transfer(from, address(0), amount);
    }
}

File 3 of 4 : SafeTransferLib.sol
// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

import {ERC20} from "../tokens/ERC20.sol";

/// @notice Safe ETH and ERC20 transfer library that gracefully handles missing return values.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SafeTransferLib.sol)
/// @dev Use with caution! Some functions in this library knowingly create dirty bits at the destination of the free memory pointer.
/// @dev Note that none of the functions in this library check that a token has code at all! That responsibility is delegated to the caller.
library SafeTransferLib {
    /*//////////////////////////////////////////////////////////////
                             ETH OPERATIONS
    //////////////////////////////////////////////////////////////*/

    function safeTransferETH(address to, uint256 amount) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Transfer the ETH and store if it succeeded or not.
            success := call(gas(), to, amount, 0, 0, 0, 0)
        }

        require(success, "ETH_TRANSFER_FAILED");
    }

    /*//////////////////////////////////////////////////////////////
                            ERC20 OPERATIONS
    //////////////////////////////////////////////////////////////*/

    function safeTransferFrom(ERC20 token, address from, address to, uint256 amount) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0x23b872dd00000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), and(from, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "from" argument.
            mstore(add(freeMemoryPointer, 36), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
            mstore(add(freeMemoryPointer, 68), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 100 because the length of our calldata totals up like so: 4 + 32 * 3.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 100, 0, 32)
            )
        }

        require(success, "TRANSFER_FROM_FAILED");
    }

    function safeTransfer(ERC20 token, address to, uint256 amount) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0xa9059cbb00000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
            )
        }

        require(success, "TRANSFER_FAILED");
    }

    function safeApprove(ERC20 token, address to, uint256 amount) internal {
        bool success;

        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)

            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0x095ea7b300000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.

            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
            )
        }

        require(success, "APPROVE_FAILED");
    }
}

File 4 of 4 : IFeeCollector.sol
// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.17;

interface IFeeCollector {
    function registerFee(address feeTaker, uint256 feeAmount, address feeToken) external;
    function registerFee(address feeTaker, uint256 feeAmount, address feeToken, bytes32 requestHash) external;
    function settleFee(bytes32 requestHash) external;
    function refundFee(bytes32 requestHash, address to) external;
}

Settings
{
  "optimizer": {
    "enabled": true,
    "runs": 200
  },
  "outputSelection": {
    "*": {
      "*": [
        "evm.bytecode",
        "evm.deployedBytecode",
        "devdoc",
        "userdoc",
        "metadata",
        "abi"
      ]
    }
  },
  "libraries": {}
}

Contract Security Audit

Contract ABI

API
[{"inputs":[],"name":"TransferFailed","type":"error"},{"inputs":[],"name":"NATIVE_TOKEN_ADDRESS","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"token","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"},{"internalType":"address","name":"swapRouter","type":"address"},{"internalType":"bytes","name":"swapPayload","type":"bytes"},{"internalType":"contract IFeeCollector","name":"feeCollector","type":"address"},{"internalType":"address","name":"feeTaker","type":"address"},{"internalType":"uint256","name":"feeAmount","type":"uint256"}],"name":"collectFeeAndExecuteSwap","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"token","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"},{"internalType":"address","name":"swapRouter","type":"address"},{"internalType":"bytes","name":"swapPayload","type":"bytes"}],"name":"executeSwap","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"swapRouter","type":"address"},{"internalType":"bytes","name":"swapPayload","type":"bytes"},{"internalType":"uint256","name":"msgValue","type":"uint256"}],"name":"executeSwapWithValue","outputs":[],"stateMutability":"nonpayable","type":"function"}]

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Deployed Bytecode

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Block Transaction Gas Used Reward
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Transaction Hash Block Value Eth2 PubKey Valid
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A contract address hosts a smart contract, which is a set of code stored on the blockchain that runs when predetermined conditions are met. Learn more about addresses in our Knowledge Base.