Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.17;
import { ReentrancyGuard } from "../Helpers/ReentrancyGuard.sol";
import { LibSwap } from "../Libraries/LibSwap.sol";
import { LibAsset } from "../Libraries/LibAsset.sol";
import { UnAuthorized } from "lifi/Errors/GenericErrors.sol";
import { ILiFi } from "../Interfaces/ILiFi.sol";
import { IERC20Proxy } from "../Interfaces/IERC20Proxy.sol";
import { ERC1155Holder } from "@openzeppelin/contracts/token/ERC1155/utils/ERC1155Holder.sol";
import { ERC721Holder } from "@openzeppelin/contracts/token/ERC721/utils/ERC721Holder.sol";
import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
/// @title Executor
/// @author LI.FI (https://li.fi)
/// @notice Arbitrary execution contract used for cross-chain swaps and message passing
/// @custom:version 2.0.0
contract Executor is ILiFi, ReentrancyGuard, ERC1155Holder, ERC721Holder {
/// Storage ///
/// @notice The address of the ERC20Proxy contract
IERC20Proxy public erc20Proxy;
/// Events ///
event ERC20ProxySet(address indexed proxy);
/// Modifiers ///
/// @dev Sends any leftover balances back to the user
modifier noLeftovers(
LibSwap.SwapData[] calldata _swaps,
address payable _leftoverReceiver
) {
uint256 numSwaps = _swaps.length;
if (numSwaps != 1) {
uint256[] memory initialBalances = _fetchBalances(_swaps);
address finalAsset = _swaps[numSwaps - 1].receivingAssetId;
uint256 curBalance = 0;
_;
for (uint256 i = 0; i < numSwaps - 1; ) {
address curAsset = _swaps[i].receivingAssetId;
// Handle multi-to-one swaps
if (curAsset != finalAsset) {
curBalance = LibAsset.getOwnBalance(curAsset);
if (curBalance > initialBalances[i]) {
LibAsset.transferAsset(
curAsset,
_leftoverReceiver,
curBalance - initialBalances[i]
);
}
}
unchecked {
++i;
}
}
} else {
_;
}
}
/// Constructor
/// @notice Initialize local variables for the Executor
/// @param _erc20Proxy The address of the ERC20Proxy contract
constructor(address _erc20Proxy) {
erc20Proxy = IERC20Proxy(_erc20Proxy);
emit ERC20ProxySet(_erc20Proxy);
}
/// External Methods ///
/// @notice Performs a swap before completing a cross-chain transaction
/// @param _transactionId the transaction id for the swap
/// @param _swapData array of data needed for swaps
/// @param _transferredAssetId token received from the other chain
/// @param _receiver address that will receive tokens in the end
function swapAndCompleteBridgeTokens(
bytes32 _transactionId,
LibSwap.SwapData[] calldata _swapData,
address _transferredAssetId,
address payable _receiver
) external payable nonReentrant {
_processSwaps(
_transactionId,
_swapData,
_transferredAssetId,
_receiver,
0,
true
);
}
/// @notice Performs a series of swaps or arbitrary executions
/// @param _transactionId the transaction id for the swap
/// @param _swapData array of data needed for swaps
/// @param _transferredAssetId token received from the other chain
/// @param _receiver address that will receive tokens in the end
/// @param _amount amount of token for swaps or arbitrary executions
function swapAndExecute(
bytes32 _transactionId,
LibSwap.SwapData[] calldata _swapData,
address _transferredAssetId,
address payable _receiver,
uint256 _amount
) external payable nonReentrant {
_processSwaps(
_transactionId,
_swapData,
_transferredAssetId,
_receiver,
_amount,
false
);
}
/// Private Methods ///
/// @notice Performs a series of swaps or arbitrary executions
/// @param _transactionId the transaction id for the swap
/// @param _swapData array of data needed for swaps
/// @param _transferredAssetId token received from the other chain
/// @param _receiver address that will receive tokens in the end
/// @param _amount amount of token for swaps or arbitrary executions
/// @param _depositAllowance If deposit approved amount of token
function _processSwaps(
bytes32 _transactionId,
LibSwap.SwapData[] calldata _swapData,
address _transferredAssetId,
address payable _receiver,
uint256 _amount,
bool _depositAllowance
) private {
uint256 startingBalance;
uint256 finalAssetStartingBalance;
address finalAssetId = _swapData[_swapData.length - 1]
.receivingAssetId;
if (!LibAsset.isNativeAsset(finalAssetId)) {
finalAssetStartingBalance = LibAsset.getOwnBalance(finalAssetId);
} else {
finalAssetStartingBalance =
LibAsset.getOwnBalance(finalAssetId) -
msg.value;
}
if (!LibAsset.isNativeAsset(_transferredAssetId)) {
startingBalance = LibAsset.getOwnBalance(_transferredAssetId);
if (_depositAllowance) {
uint256 allowance = IERC20(_transferredAssetId).allowance(
msg.sender,
address(this)
);
LibAsset.depositAsset(_transferredAssetId, allowance);
} else {
erc20Proxy.transferFrom(
_transferredAssetId,
msg.sender,
address(this),
_amount
);
}
} else {
startingBalance =
LibAsset.getOwnBalance(_transferredAssetId) -
msg.value;
}
_executeSwaps(_transactionId, _swapData, _receiver);
uint256 postSwapBalance = LibAsset.getOwnBalance(_transferredAssetId);
if (postSwapBalance > startingBalance) {
LibAsset.transferAsset(
_transferredAssetId,
_receiver,
postSwapBalance - startingBalance
);
}
uint256 finalAssetPostSwapBalance = LibAsset.getOwnBalance(
finalAssetId
);
if (finalAssetPostSwapBalance > finalAssetStartingBalance) {
LibAsset.transferAsset(
finalAssetId,
_receiver,
finalAssetPostSwapBalance - finalAssetStartingBalance
);
}
emit LiFiTransferCompleted(
_transactionId,
_transferredAssetId,
_receiver,
finalAssetPostSwapBalance,
block.timestamp
);
}
/// @dev Executes swaps one after the other
/// @param _transactionId the transaction id for the swap
/// @param _swapData Array of data used to execute swaps
/// @param _leftoverReceiver Address to receive lefover tokens
function _executeSwaps(
bytes32 _transactionId,
LibSwap.SwapData[] calldata _swapData,
address payable _leftoverReceiver
) private noLeftovers(_swapData, _leftoverReceiver) {
uint256 numSwaps = _swapData.length;
for (uint256 i = 0; i < numSwaps; ) {
if (_swapData[i].callTo == address(erc20Proxy)) {
revert UnAuthorized(); // Prevent calling ERC20 Proxy directly
}
LibSwap.SwapData calldata currentSwapData = _swapData[i];
LibSwap.swap(_transactionId, currentSwapData);
unchecked {
++i;
}
}
}
/// @dev Fetches balances of tokens to be swapped before swapping.
/// @param _swapData Array of data used to execute swaps
/// @return uint256[] Array of token balances.
function _fetchBalances(
LibSwap.SwapData[] calldata _swapData
) private view returns (uint256[] memory) {
uint256 numSwaps = _swapData.length;
uint256[] memory balances = new uint256[](numSwaps);
address asset;
for (uint256 i = 0; i < numSwaps; ) {
asset = _swapData[i].receivingAssetId;
balances[i] = LibAsset.getOwnBalance(asset);
if (LibAsset.isNativeAsset(asset)) {
balances[i] -= msg.value;
}
unchecked {
++i;
}
}
return balances;
}
/// @dev required for receiving native assets from destination swaps
// solhint-disable-next-line no-empty-blocks
receive() external payable {}
}
// SPDX-License-Identifier: UNLICENSED
/// @custom:version 1.0.0
pragma solidity ^0.8.17;
/// @title Reentrancy Guard
/// @author LI.FI (https://li.fi)
/// @notice Abstract contract to provide protection against reentrancy
abstract contract ReentrancyGuard {
/// Storage ///
bytes32 private constant NAMESPACE = keccak256("com.lifi.reentrancyguard");
/// Types ///
struct ReentrancyStorage {
uint256 status;
}
/// Errors ///
error ReentrancyError();
/// Constants ///
uint256 private constant _NOT_ENTERED = 0;
uint256 private constant _ENTERED = 1;
/// Modifiers ///
modifier nonReentrant() {
ReentrancyStorage storage s = reentrancyStorage();
if (s.status == _ENTERED) revert ReentrancyError();
s.status = _ENTERED;
_;
s.status = _NOT_ENTERED;
}
/// Private Methods ///
/// @dev fetch local storage
function reentrancyStorage()
private
pure
returns (ReentrancyStorage storage data)
{
bytes32 position = NAMESPACE;
// solhint-disable-next-line no-inline-assembly
assembly {
data.slot := position
}
}
}
// SPDX-License-Identifier: MIT
/// @custom:version 1.0.0
pragma solidity ^0.8.17;
import { LibAsset } from "./LibAsset.sol";
import { LibUtil } from "./LibUtil.sol";
import { InvalidContract, NoSwapFromZeroBalance, InsufficientBalance } from "../Errors/GenericErrors.sol";
import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
library LibSwap {
struct SwapData {
address callTo;
address approveTo;
address sendingAssetId;
address receivingAssetId;
uint256 fromAmount;
bytes callData;
bool requiresDeposit;
}
event AssetSwapped(
bytes32 transactionId,
address dex,
address fromAssetId,
address toAssetId,
uint256 fromAmount,
uint256 toAmount,
uint256 timestamp
);
function swap(bytes32 transactionId, SwapData calldata _swap) internal {
if (!LibAsset.isContract(_swap.callTo)) revert InvalidContract();
uint256 fromAmount = _swap.fromAmount;
if (fromAmount == 0) revert NoSwapFromZeroBalance();
uint256 nativeValue = LibAsset.isNativeAsset(_swap.sendingAssetId)
? _swap.fromAmount
: 0;
uint256 initialSendingAssetBalance = LibAsset.getOwnBalance(
_swap.sendingAssetId
);
uint256 initialReceivingAssetBalance = LibAsset.getOwnBalance(
_swap.receivingAssetId
);
if (nativeValue == 0) {
LibAsset.maxApproveERC20(
IERC20(_swap.sendingAssetId),
_swap.approveTo,
_swap.fromAmount
);
}
if (initialSendingAssetBalance < _swap.fromAmount) {
revert InsufficientBalance(
_swap.fromAmount,
initialSendingAssetBalance
);
}
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory res) = _swap.callTo.call{
value: nativeValue
}(_swap.callData);
if (!success) {
LibUtil.revertWith(res);
}
uint256 newBalance = LibAsset.getOwnBalance(_swap.receivingAssetId);
emit AssetSwapped(
transactionId,
_swap.callTo,
_swap.sendingAssetId,
_swap.receivingAssetId,
_swap.fromAmount,
newBalance > initialReceivingAssetBalance
? newBalance - initialReceivingAssetBalance
: newBalance,
block.timestamp
);
}
}
// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.17;
import { InsufficientBalance, NullAddrIsNotAnERC20Token, NullAddrIsNotAValidSpender, NoTransferToNullAddress, InvalidAmount, NativeAssetTransferFailed } from "../Errors/GenericErrors.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import { LibSwap } from "./LibSwap.sol";
/// @title LibAsset
/// @custom:version 1.0.1
/// @notice This library contains helpers for dealing with onchain transfers
/// of assets, including accounting for the native asset `assetId`
/// conventions and any noncompliant ERC20 transfers
library LibAsset {
uint256 private constant MAX_UINT = type(uint256).max;
address internal constant NULL_ADDRESS = address(0);
address internal constant NON_EVM_ADDRESS =
0x11f111f111f111F111f111f111F111f111f111F1;
/// @dev All native assets use the empty address for their asset id
/// by convention
address internal constant NATIVE_ASSETID = NULL_ADDRESS; //address(0)
/// @notice Gets the balance of the inheriting contract for the given asset
/// @param assetId The asset identifier to get the balance of
/// @return Balance held by contracts using this library
function getOwnBalance(address assetId) internal view returns (uint256) {
return
isNativeAsset(assetId)
? address(this).balance
: IERC20(assetId).balanceOf(address(this));
}
/// @notice Transfers ether from the inheriting contract to a given
/// recipient
/// @param recipient Address to send ether to
/// @param amount Amount to send to given recipient
function transferNativeAsset(
address payable recipient,
uint256 amount
) private {
if (recipient == NULL_ADDRESS) revert NoTransferToNullAddress();
if (amount > address(this).balance)
revert InsufficientBalance(amount, address(this).balance);
// solhint-disable-next-line avoid-low-level-calls
(bool success, ) = recipient.call{ value: amount }("");
if (!success) revert NativeAssetTransferFailed();
}
/// @notice If the current allowance is insufficient, the allowance for a given spender
/// is set to MAX_UINT.
/// @param assetId Token address to transfer
/// @param spender Address to give spend approval to
/// @param amount Amount to approve for spending
function maxApproveERC20(
IERC20 assetId,
address spender,
uint256 amount
) internal {
if (isNativeAsset(address(assetId))) {
return;
}
if (spender == NULL_ADDRESS) {
revert NullAddrIsNotAValidSpender();
}
if (assetId.allowance(address(this), spender) < amount) {
SafeERC20.safeApprove(IERC20(assetId), spender, 0);
SafeERC20.safeApprove(IERC20(assetId), spender, MAX_UINT);
}
}
/// @notice Transfers tokens from the inheriting contract to a given
/// recipient
/// @param assetId Token address to transfer
/// @param recipient Address to send token to
/// @param amount Amount to send to given recipient
function transferERC20(
address assetId,
address recipient,
uint256 amount
) private {
if (isNativeAsset(assetId)) {
revert NullAddrIsNotAnERC20Token();
}
if (recipient == NULL_ADDRESS) {
revert NoTransferToNullAddress();
}
uint256 assetBalance = IERC20(assetId).balanceOf(address(this));
if (amount > assetBalance) {
revert InsufficientBalance(amount, assetBalance);
}
SafeERC20.safeTransfer(IERC20(assetId), recipient, amount);
}
/// @notice Transfers tokens from a sender to a given recipient
/// @param assetId Token address to transfer
/// @param from Address of sender/owner
/// @param to Address of recipient/spender
/// @param amount Amount to transfer from owner to spender
function transferFromERC20(
address assetId,
address from,
address to,
uint256 amount
) internal {
if (isNativeAsset(assetId)) {
revert NullAddrIsNotAnERC20Token();
}
if (to == NULL_ADDRESS) {
revert NoTransferToNullAddress();
}
IERC20 asset = IERC20(assetId);
uint256 prevBalance = asset.balanceOf(to);
SafeERC20.safeTransferFrom(asset, from, to, amount);
if (asset.balanceOf(to) - prevBalance != amount) {
revert InvalidAmount();
}
}
function depositAsset(address assetId, uint256 amount) internal {
if (amount == 0) revert InvalidAmount();
if (isNativeAsset(assetId)) {
if (msg.value < amount) revert InvalidAmount();
} else {
uint256 balance = IERC20(assetId).balanceOf(msg.sender);
if (balance < amount) revert InsufficientBalance(amount, balance);
transferFromERC20(assetId, msg.sender, address(this), amount);
}
}
function depositAssets(LibSwap.SwapData[] calldata swaps) internal {
for (uint256 i = 0; i < swaps.length; ) {
LibSwap.SwapData calldata swap = swaps[i];
if (swap.requiresDeposit) {
depositAsset(swap.sendingAssetId, swap.fromAmount);
}
unchecked {
i++;
}
}
}
/// @notice Determines whether the given assetId is the native asset
/// @param assetId The asset identifier to evaluate
/// @return Boolean indicating if the asset is the native asset
function isNativeAsset(address assetId) internal pure returns (bool) {
return assetId == NATIVE_ASSETID;
}
/// @notice Wrapper function to transfer a given asset (native or erc20) to
/// some recipient. Should handle all non-compliant return value
/// tokens as well by using the SafeERC20 contract by open zeppelin.
/// @param assetId Asset id for transfer (address(0) for native asset,
/// token address for erc20s)
/// @param recipient Address to send asset to
/// @param amount Amount to send to given recipient
function transferAsset(
address assetId,
address payable recipient,
uint256 amount
) internal {
isNativeAsset(assetId)
? transferNativeAsset(recipient, amount)
: transferERC20(assetId, recipient, amount);
}
/// @dev Checks whether the given address is a contract and contains code
function isContract(address _contractAddr) internal view returns (bool) {
uint256 size;
// solhint-disable-next-line no-inline-assembly
assembly {
size := extcodesize(_contractAddr)
}
return size > 0;
}
}
// SPDX-License-Identifier: MIT
/// @custom:version 1.0.0
pragma solidity ^0.8.17;
error AlreadyInitialized();
error CannotAuthoriseSelf();
error CannotBridgeToSameNetwork();
error ContractCallNotAllowed();
error CumulativeSlippageTooHigh(uint256 minAmount, uint256 receivedAmount);
error DiamondIsPaused();
error ExternalCallFailed();
error FunctionDoesNotExist();
error InformationMismatch();
error InsufficientBalance(uint256 required, uint256 balance);
error InvalidAmount();
error InvalidCallData();
error InvalidConfig();
error InvalidContract();
error InvalidDestinationChain();
error InvalidFallbackAddress();
error InvalidReceiver();
error InvalidSendingToken();
error NativeAssetNotSupported();
error NativeAssetTransferFailed();
error NoSwapDataProvided();
error NoSwapFromZeroBalance();
error NotAContract();
error NotInitialized();
error NoTransferToNullAddress();
error NullAddrIsNotAnERC20Token();
error NullAddrIsNotAValidSpender();
error OnlyContractOwner();
error RecoveryAddressCannotBeZero();
error ReentrancyError();
error TokenNotSupported();
error UnAuthorized();
error UnsupportedChainId(uint256 chainId);
error WithdrawFailed();
error ZeroAmount();
// SPDX-License-Identifier: MIT
/// @custom:version 1.0.0
pragma solidity ^0.8.17;
interface ILiFi {
/// Structs ///
struct BridgeData {
bytes32 transactionId;
string bridge;
string integrator;
address referrer;
address sendingAssetId;
address receiver;
uint256 minAmount;
uint256 destinationChainId;
bool hasSourceSwaps;
bool hasDestinationCall;
}
/// Events ///
event LiFiTransferStarted(ILiFi.BridgeData bridgeData);
event LiFiTransferCompleted(
bytes32 indexed transactionId,
address receivingAssetId,
address receiver,
uint256 amount,
uint256 timestamp
);
event LiFiTransferRecovered(
bytes32 indexed transactionId,
address receivingAssetId,
address receiver,
uint256 amount,
uint256 timestamp
);
event LiFiGenericSwapCompleted(
bytes32 indexed transactionId,
string integrator,
string referrer,
address receiver,
address fromAssetId,
address toAssetId,
uint256 fromAmount,
uint256 toAmount
);
// Deprecated but kept here to include in ABI to parse historic events
event LiFiSwappedGeneric(
bytes32 indexed transactionId,
string integrator,
string referrer,
address fromAssetId,
address toAssetId,
uint256 fromAmount,
uint256 toAmount
);
}
// SPDX-License-Identifier: MIT
/// @custom:version 1.0.0
pragma solidity ^0.8.17;
interface IERC20Proxy {
function transferFrom(
address tokenAddress,
address from,
address to,
uint256 amount
) external;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC1155/utils/ERC1155Holder.sol)
pragma solidity ^0.8.0;
import "./ERC1155Receiver.sol";
/**
* Simple implementation of `ERC1155Receiver` that will allow a contract to hold ERC1155 tokens.
*
* IMPORTANT: When inheriting this contract, you must include a way to use the received tokens, otherwise they will be
* stuck.
*
* @dev _Available since v3.1._
*/
contract ERC1155Holder is ERC1155Receiver {
function onERC1155Received(
address,
address,
uint256,
uint256,
bytes memory
) public virtual override returns (bytes4) {
return this.onERC1155Received.selector;
}
function onERC1155BatchReceived(
address,
address,
uint256[] memory,
uint256[] memory,
bytes memory
) public virtual override returns (bytes4) {
return this.onERC1155BatchReceived.selector;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC721/utils/ERC721Holder.sol)
pragma solidity ^0.8.0;
import "../IERC721Receiver.sol";
/**
* @dev Implementation of the {IERC721Receiver} interface.
*
* Accepts all token transfers.
* Make sure the contract is able to use its token with {IERC721-safeTransferFrom}, {IERC721-approve} or {IERC721-setApprovalForAll}.
*/
contract ERC721Holder is IERC721Receiver {
/**
* @dev See {IERC721Receiver-onERC721Received}.
*
* Always returns `IERC721Receiver.onERC721Received.selector`.
*/
function onERC721Received(address, address, uint256, bytes memory) public virtual override returns (bytes4) {
return this.onERC721Received.selector;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `from` to `to` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(address from, address to, uint256 amount) external returns (bool);
}
// SPDX-License-Identifier: MIT
/// @custom:version 1.0.0
pragma solidity ^0.8.17;
import "./LibBytes.sol";
library LibUtil {
using LibBytes for bytes;
function getRevertMsg(
bytes memory _res
) internal pure returns (string memory) {
// If the _res length is less than 68, then the transaction failed silently (without a revert message)
if (_res.length < 68) return "Transaction reverted silently";
bytes memory revertData = _res.slice(4, _res.length - 4); // Remove the selector which is the first 4 bytes
return abi.decode(revertData, (string)); // All that remains is the revert string
}
/// @notice Determines whether the given address is the zero address
/// @param addr The address to verify
/// @return Boolean indicating if the address is the zero address
function isZeroAddress(address addr) internal pure returns (bool) {
return addr == address(0);
}
function revertWith(bytes memory data) internal pure {
assembly {
let dataSize := mload(data) // Load the size of the data
let dataPtr := add(data, 0x20) // Advance data pointer to the next word
revert(dataPtr, dataSize) // Revert with the given data
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
import "../extensions/IERC20Permit.sol";
import "../../../utils/Address.sol";
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20 {
using Address for address;
/**
* @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeTransfer(IERC20 token, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
/**
* @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
* calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
*/
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IERC20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
function safeApprove(IERC20 token, address spender, uint256 value) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
require(
(value == 0) || (token.allowance(address(this), spender) == 0),
"SafeERC20: approve from non-zero to non-zero allowance"
);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
/**
* @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 oldAllowance = token.allowance(address(this), spender);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
}
/**
* @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
unchecked {
uint256 oldAllowance = token.allowance(address(this), spender);
require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
}
}
/**
* @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful. Compatible with tokens that require the approval to be set to
* 0 before setting it to a non-zero value.
*/
function forceApprove(IERC20 token, address spender, uint256 value) internal {
bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);
if (!_callOptionalReturnBool(token, approvalCall)) {
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
_callOptionalReturn(token, approvalCall);
}
}
/**
* @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
* Revert on invalid signature.
*/
function safePermit(
IERC20Permit token,
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) internal {
uint256 nonceBefore = token.nonces(owner);
token.permit(owner, spender, value, deadline, v, r, s);
uint256 nonceAfter = token.nonces(owner);
require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function _callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We use {Address-functionCall} to perform this call, which verifies that
// the target address contains contract code and also asserts for success in the low-level call.
bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
require(returndata.length == 0 || abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*
* This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
*/
function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We cannot use {Address-functionCall} here since this should return false
// and not revert is the subcall reverts.
(bool success, bytes memory returndata) = address(token).call(data);
return
success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC1155/utils/ERC1155Receiver.sol)
pragma solidity ^0.8.0;
import "../IERC1155Receiver.sol";
import "../../../utils/introspection/ERC165.sol";
/**
* @dev _Available since v3.1._
*/
abstract contract ERC1155Receiver is ERC165, IERC1155Receiver {
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
return interfaceId == type(IERC1155Receiver).interfaceId || super.supportsInterface(interfaceId);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)
pragma solidity ^0.8.0;
/**
* @title ERC721 token receiver interface
* @dev Interface for any contract that wants to support safeTransfers
* from ERC721 asset contracts.
*/
interface IERC721Receiver {
/**
* @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
* by `operator` from `from`, this function is called.
*
* It must return its Solidity selector to confirm the token transfer.
* If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
*
* The selector can be obtained in Solidity with `IERC721Receiver.onERC721Received.selector`.
*/
function onERC721Received(
address operator,
address from,
uint256 tokenId,
bytes calldata data
) external returns (bytes4);
}
// SPDX-License-Identifier: MIT
/// @custom:version 1.0.0
pragma solidity ^0.8.17;
library LibBytes {
// solhint-disable no-inline-assembly
// LibBytes specific errors
error SliceOverflow();
error SliceOutOfBounds();
error AddressOutOfBounds();
bytes16 private constant _SYMBOLS = "0123456789abcdef";
// -------------------------
function slice(
bytes memory _bytes,
uint256 _start,
uint256 _length
) internal pure returns (bytes memory) {
if (_length + 31 < _length) revert SliceOverflow();
if (_bytes.length < _start + _length) revert SliceOutOfBounds();
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)
//zero out the 32 bytes slice we are about to return
//we need to do it because Solidity does not garbage collect
mstore(tempBytes, 0)
mstore(0x40, add(tempBytes, 0x20))
}
}
return tempBytes;
}
function toAddress(
bytes memory _bytes,
uint256 _start
) internal pure returns (address) {
if (_bytes.length < _start + 20) {
revert AddressOutOfBounds();
}
address tempAddress;
assembly {
tempAddress := div(
mload(add(add(_bytes, 0x20), _start)),
0x1000000000000000000000000
)
}
return tempAddress;
}
/// Copied from OpenZeppelin's `Strings.sol` utility library.
/// https://github.com/OpenZeppelin/openzeppelin-contracts/blob/8335676b0e99944eef6a742e16dcd9ff6e68e609/contracts/utils/Strings.sol
function toHexString(
uint256 value,
uint256 length
) internal pure returns (string memory) {
bytes memory buffer = new bytes(2 * length + 2);
buffer[0] = "0";
buffer[1] = "x";
for (uint256 i = 2 * length + 1; i > 1; --i) {
buffer[i] = _SYMBOLS[value & 0xf];
value >>= 4;
}
require(value == 0, "Strings: hex length insufficient");
return string(buffer);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/extensions/IERC20Permit.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
* https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
*
* Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
* presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
* need to send a transaction, and thus is not required to hold Ether at all.
*/
interface IERC20Permit {
/**
* @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
* given ``owner``'s signed approval.
*
* IMPORTANT: The same issues {IERC20-approve} has related to transaction
* ordering also apply here.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `deadline` must be a timestamp in the future.
* - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
* over the EIP712-formatted function arguments.
* - the signature must use ``owner``'s current nonce (see {nonces}).
*
* For more information on the signature format, see the
* https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
* section].
*/
function permit(
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) external;
/**
* @dev Returns the current nonce for `owner`. This value must be
* included whenever a signature is generated for {permit}.
*
* Every successful call to {permit} increases ``owner``'s nonce by one. This
* prevents a signature from being used multiple times.
*/
function nonces(address owner) external view returns (uint256);
/**
* @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
*/
// solhint-disable-next-line func-name-mixedcase
function DOMAIN_SEPARATOR() external view returns (bytes32);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)
pragma solidity ^0.8.1;
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
*
* Furthermore, `isContract` will also return true if the target contract within
* the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
* which only has an effect at the end of a transaction.
* ====
*
* [IMPORTANT]
* ====
* You shouldn't rely on `isContract` to protect against flash loan attacks!
*
* Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
* like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
* constructor.
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize/address.code.length, which returns 0
// for contracts in construction, since the code is only stored at the end
// of the constructor execution.
return account.code.length > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://consensys.net/diligence/blog/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/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
(bool success, bytes memory returndata) = target.call{value: value}(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(
address target,
bytes memory data,
string memory errorMessage
) internal view returns (bytes memory) {
(bool success, bytes memory returndata) = target.staticcall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
(bool success, bytes memory returndata) = target.delegatecall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
* the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
*
* _Available since v4.8._
*/
function verifyCallResultFromTarget(
address target,
bool success,
bytes memory returndata,
string memory errorMessage
) internal view returns (bytes memory) {
if (success) {
if (returndata.length == 0) {
// only check isContract if the call was successful and the return data is empty
// otherwise we already know that it was a contract
require(isContract(target), "Address: call to non-contract");
}
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
/**
* @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason or using the provided one.
*
* _Available since v4.3._
*/
function verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) internal pure returns (bytes memory) {
if (success) {
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
function _revert(bytes memory returndata, string memory errorMessage) private pure {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
/// @solidity memory-safe-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC1155/IERC1155Receiver.sol)
pragma solidity ^0.8.0;
import "../../utils/introspection/IERC165.sol";
/**
* @dev _Available since v3.1._
*/
interface IERC1155Receiver is IERC165 {
/**
* @dev Handles the receipt of a single ERC1155 token type. This function is
* called at the end of a `safeTransferFrom` after the balance has been updated.
*
* NOTE: To accept the transfer, this must return
* `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))`
* (i.e. 0xf23a6e61, or its own function selector).
*
* @param operator The address which initiated the transfer (i.e. msg.sender)
* @param from The address which previously owned the token
* @param id The ID of the token being transferred
* @param value The amount of tokens being transferred
* @param data Additional data with no specified format
* @return `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))` if transfer is allowed
*/
function onERC1155Received(
address operator,
address from,
uint256 id,
uint256 value,
bytes calldata data
) external returns (bytes4);
/**
* @dev Handles the receipt of a multiple ERC1155 token types. This function
* is called at the end of a `safeBatchTransferFrom` after the balances have
* been updated.
*
* NOTE: To accept the transfer(s), this must return
* `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))`
* (i.e. 0xbc197c81, or its own function selector).
*
* @param operator The address which initiated the batch transfer (i.e. msg.sender)
* @param from The address which previously owned the token
* @param ids An array containing ids of each token being transferred (order and length must match values array)
* @param values An array containing amounts of each token being transferred (order and length must match ids array)
* @param data Additional data with no specified format
* @return `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))` if transfer is allowed
*/
function onERC1155BatchReceived(
address operator,
address from,
uint256[] calldata ids,
uint256[] calldata values,
bytes calldata data
) external returns (bytes4);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
pragma solidity ^0.8.0;
import "./IERC165.sol";
/**
* @dev Implementation of the {IERC165} interface.
*
* Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
* for the additional interface id that will be supported. For example:
*
* ```solidity
* function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
* return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
* }
* ```
*
* Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
*/
abstract contract ERC165 is IERC165 {
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
return interfaceId == type(IERC165).interfaceId;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC165 standard, as defined in the
* https://eips.ethereum.org/EIPS/eip-165[EIP].
*
* Implementers can declare support of contract interfaces, which can then be
* queried by others ({ERC165Checker}).
*
* For an implementation, see {ERC165}.
*/
interface IERC165 {
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
* to learn more about how these ids are created.
*
* This function call must use less than 30 000 gas.
*/
function supportsInterface(bytes4 interfaceId) external view returns (bool);
}