Contract Name:
GenericSwapFacetV3
Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.17;
import { ILiFi } from "../Interfaces/ILiFi.sol";
import { LibUtil } from "../Libraries/LibUtil.sol";
import { LibSwap } from "../Libraries/LibSwap.sol";
import { LibAllowList } from "../Libraries/LibAllowList.sol";
import { LibAsset } from "../Libraries/LibAsset.sol";
import { ContractCallNotAllowed, CumulativeSlippageTooHigh, NativeAssetTransferFailed } from "../Errors/GenericErrors.sol";
import { ERC20, SafeTransferLib } from "solmate/utils/SafeTransferLib.sol";
/// @title GenericSwapFacetV3
/// @author LI.FI (https://li.fi)
/// @notice Provides gas-optimized functionality for fee collection and for swapping through any APPROVED DEX
/// @dev Can only execute calldata for APPROVED function selectors
/// @custom:version 1.0.1
contract GenericSwapFacetV3 is ILiFi {
using SafeTransferLib for ERC20;
/// Storage
address public immutable NATIVE_ADDRESS;
/// Constructor
/// @param _nativeAddress the address of the native token for this network
constructor(address _nativeAddress) {
NATIVE_ADDRESS = _nativeAddress;
}
/// External Methods ///
// SINGLE SWAPS
/// @notice Performs a single swap from an ERC20 token to another ERC20 token
/// @param _transactionId the transaction id associated with the operation
/// @param _integrator the name of the integrator
/// @param _referrer the address of the referrer
/// @param _receiver the address to receive the swapped tokens into (also excess tokens)
/// @param _minAmountOut the minimum amount of the final asset to receive
/// @param _swapData an object containing swap related data to perform swaps before bridging
function swapTokensSingleV3ERC20ToERC20(
bytes32 _transactionId,
string calldata _integrator,
string calldata _referrer,
address payable _receiver,
uint256 _minAmountOut,
LibSwap.SwapData calldata _swapData
) external {
_depositAndSwapERC20Single(_swapData, _receiver);
address receivingAssetId = _swapData.receivingAssetId;
address sendingAssetId = _swapData.sendingAssetId;
// get contract's balance (which will be sent in full to user)
uint256 amountReceived = ERC20(receivingAssetId).balanceOf(
address(this)
);
// ensure that minAmountOut was received
if (amountReceived < _minAmountOut)
revert CumulativeSlippageTooHigh(_minAmountOut, amountReceived);
// transfer funds to receiver
ERC20(receivingAssetId).safeTransfer(_receiver, amountReceived);
// emit events (both required for tracking)
uint256 fromAmount = _swapData.fromAmount;
emit LibSwap.AssetSwapped(
_transactionId,
_swapData.callTo,
sendingAssetId,
receivingAssetId,
fromAmount,
amountReceived,
block.timestamp
);
emit ILiFi.LiFiGenericSwapCompleted(
_transactionId,
_integrator,
_referrer,
_receiver,
sendingAssetId,
receivingAssetId,
fromAmount,
amountReceived
);
}
/// @notice Performs a single swap from an ERC20 token to the network's native token
/// @param _transactionId the transaction id associated with the operation
/// @param _integrator the name of the integrator
/// @param _referrer the address of the referrer
/// @param _receiver the address to receive the swapped tokens into (also excess tokens)
/// @param _minAmountOut the minimum amount of the final asset to receive
/// @param _swapData an object containing swap related data to perform swaps before bridging
function swapTokensSingleV3ERC20ToNative(
bytes32 _transactionId,
string calldata _integrator,
string calldata _referrer,
address payable _receiver,
uint256 _minAmountOut,
LibSwap.SwapData calldata _swapData
) external {
_depositAndSwapERC20Single(_swapData, _receiver);
// get contract's balance (which will be sent in full to user)
uint256 amountReceived = address(this).balance;
// ensure that minAmountOut was received
if (amountReceived < _minAmountOut)
revert CumulativeSlippageTooHigh(_minAmountOut, amountReceived);
// transfer funds to receiver
// solhint-disable-next-line avoid-low-level-calls
(bool success, ) = _receiver.call{ value: amountReceived }("");
if (!success) revert NativeAssetTransferFailed();
// emit events (both required for tracking)
address sendingAssetId = _swapData.sendingAssetId;
uint256 fromAmount = _swapData.fromAmount;
emit LibSwap.AssetSwapped(
_transactionId,
_swapData.callTo,
sendingAssetId,
NATIVE_ADDRESS,
fromAmount,
amountReceived,
block.timestamp
);
emit ILiFi.LiFiGenericSwapCompleted(
_transactionId,
_integrator,
_referrer,
_receiver,
sendingAssetId,
NATIVE_ADDRESS,
fromAmount,
amountReceived
);
}
/// @notice Performs a single swap from the network's native token to ERC20 token
/// @param _transactionId the transaction id associated with the operation
/// @param _integrator the name of the integrator
/// @param _referrer the address of the referrer
/// @param _receiver the address to receive the swapped tokens into (also excess tokens)
/// @param _minAmountOut the minimum amount of the final asset to receive
/// @param _swapData an object containing swap related data to perform swaps before bridging
function swapTokensSingleV3NativeToERC20(
bytes32 _transactionId,
string calldata _integrator,
string calldata _referrer,
address payable _receiver,
uint256 _minAmountOut,
LibSwap.SwapData calldata _swapData
) external payable {
address callTo = _swapData.callTo;
// ensure that contract (callTo) and function selector are whitelisted
if (
!(LibAllowList.contractIsAllowed(callTo) &&
LibAllowList.selectorIsAllowed(bytes4(_swapData.callData[:4])))
) revert ContractCallNotAllowed();
// execute swap
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory res) = callTo.call{ value: msg.value }(
_swapData.callData
);
if (!success) {
LibUtil.revertWith(res);
}
_returnPositiveSlippageNative(_receiver);
// get contract's balance (which will be sent in full to user)
address receivingAssetId = _swapData.receivingAssetId;
uint256 amountReceived = ERC20(receivingAssetId).balanceOf(
address(this)
);
// ensure that minAmountOut was received
if (amountReceived < _minAmountOut)
revert CumulativeSlippageTooHigh(_minAmountOut, amountReceived);
// transfer funds to receiver
ERC20(receivingAssetId).safeTransfer(_receiver, amountReceived);
// emit events (both required for tracking)
uint256 fromAmount = _swapData.fromAmount;
emit LibSwap.AssetSwapped(
_transactionId,
callTo,
NATIVE_ADDRESS,
receivingAssetId,
fromAmount,
amountReceived,
block.timestamp
);
emit ILiFi.LiFiGenericSwapCompleted(
_transactionId,
_integrator,
_referrer,
_receiver,
NATIVE_ADDRESS,
receivingAssetId,
fromAmount,
amountReceived
);
}
// MULTIPLE SWAPS
/// @notice Performs multiple swaps in one transaction, starting with ERC20 and ending with native
/// @param _transactionId the transaction id associated with the operation
/// @param _integrator the name of the integrator
/// @param _referrer the address of the referrer
/// @param _receiver the address to receive the swapped tokens into (also excess tokens)
/// @param _minAmountOut the minimum amount of the final asset to receive
/// @param _swapData an object containing swap related data to perform swaps before bridging
function swapTokensMultipleV3ERC20ToNative(
bytes32 _transactionId,
string calldata _integrator,
string calldata _referrer,
address payable _receiver,
uint256 _minAmountOut,
LibSwap.SwapData[] calldata _swapData
) external {
_depositMultipleERC20Tokens(_swapData);
_executeSwaps(_swapData, _transactionId, _receiver);
_transferNativeTokensAndEmitEvent(
_transactionId,
_integrator,
_referrer,
_receiver,
_minAmountOut,
_swapData
);
}
/// @notice Performs multiple swaps in one transaction, starting with ERC20 and ending with ERC20
/// @param _transactionId the transaction id associated with the operation
/// @param _integrator the name of the integrator
/// @param _referrer the address of the referrer
/// @param _receiver the address to receive the swapped tokens into (also excess tokens)
/// @param _minAmountOut the minimum amount of the final asset to receive
/// @param _swapData an object containing swap related data to perform swaps before bridging
function swapTokensMultipleV3ERC20ToERC20(
bytes32 _transactionId,
string calldata _integrator,
string calldata _referrer,
address payable _receiver,
uint256 _minAmountOut,
LibSwap.SwapData[] calldata _swapData
) external {
_depositMultipleERC20Tokens(_swapData);
_executeSwaps(_swapData, _transactionId, _receiver);
_transferERC20TokensAndEmitEvent(
_transactionId,
_integrator,
_referrer,
_receiver,
_minAmountOut,
_swapData
);
}
/// @notice Performs multiple swaps in one transaction, starting with native and ending with ERC20
/// @param _transactionId the transaction id associated with the operation
/// @param _integrator the name of the integrator
/// @param _referrer the address of the referrer
/// @param _receiver the address to receive the swapped tokens into (also excess tokens)
/// @param _minAmountOut the minimum amount of the final asset to receive
/// @param _swapData an object containing swap related data to perform swaps before bridging
function swapTokensMultipleV3NativeToERC20(
bytes32 _transactionId,
string calldata _integrator,
string calldata _referrer,
address payable _receiver,
uint256 _minAmountOut,
LibSwap.SwapData[] calldata _swapData
) external payable {
_executeSwaps(_swapData, _transactionId, _receiver);
_transferERC20TokensAndEmitEvent(
_transactionId,
_integrator,
_referrer,
_receiver,
_minAmountOut,
_swapData
);
}
/// Private helper methods ///
function _depositMultipleERC20Tokens(
LibSwap.SwapData[] calldata _swapData
) private {
// initialize variables before loop to save gas
uint256 numOfSwaps = _swapData.length;
LibSwap.SwapData calldata currentSwap;
// go through all swaps and deposit tokens, where required
for (uint256 i = 0; i < numOfSwaps; ) {
currentSwap = _swapData[i];
if (currentSwap.requiresDeposit) {
// we will not check msg.value as tx will fail anyway if not enough value available
// thus we only deposit ERC20 tokens here
ERC20(currentSwap.sendingAssetId).safeTransferFrom(
msg.sender,
address(this),
currentSwap.fromAmount
);
}
unchecked {
++i;
}
}
}
function _depositAndSwapERC20Single(
LibSwap.SwapData calldata _swapData,
address _receiver
) private {
ERC20 sendingAsset = ERC20(_swapData.sendingAssetId);
uint256 fromAmount = _swapData.fromAmount;
// deposit funds
sendingAsset.safeTransferFrom(msg.sender, address(this), fromAmount);
// ensure that contract (callTo) and function selector are whitelisted
address callTo = _swapData.callTo;
address approveTo = _swapData.approveTo;
bytes calldata callData = _swapData.callData;
if (
!(LibAllowList.contractIsAllowed(callTo) &&
LibAllowList.selectorIsAllowed(bytes4(callData[:4])))
) revert ContractCallNotAllowed();
// ensure that approveTo address is also whitelisted if it differs from callTo
if (approveTo != callTo && !LibAllowList.contractIsAllowed(approveTo))
revert ContractCallNotAllowed();
// check if the current allowance is sufficient
uint256 currentAllowance = sendingAsset.allowance(
address(this),
approveTo
);
// check if existing allowance is sufficient
if (currentAllowance < fromAmount) {
// check if is non-zero, set to 0 if not
if (currentAllowance != 0) sendingAsset.safeApprove(approveTo, 0);
// set allowance to uint max to avoid future approvals
sendingAsset.safeApprove(approveTo, type(uint256).max);
}
// execute swap
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory res) = callTo.call(callData);
if (!success) {
LibUtil.revertWith(res);
}
_returnPositiveSlippageERC20(sendingAsset, _receiver);
}
// @dev: this function will not work with swapData that has multiple swaps with the same sendingAssetId
// as the _returnPositiveSlippage... functionality will refund all remaining tokens after the first swap
// We accept this fact since the use case is not common yet. As an alternative you can always use the
// "swapTokensGeneric" function of the original GenericSwapFacet
function _executeSwaps(
LibSwap.SwapData[] calldata _swapData,
bytes32 _transactionId,
address _receiver
) private {
// initialize variables before loop to save gas
uint256 numOfSwaps = _swapData.length;
ERC20 sendingAsset;
address sendingAssetId;
address receivingAssetId;
LibSwap.SwapData calldata currentSwap;
bool success;
bytes memory returnData;
uint256 currentAllowance;
// go through all swaps
for (uint256 i = 0; i < numOfSwaps; ) {
currentSwap = _swapData[i];
sendingAssetId = currentSwap.sendingAssetId;
sendingAsset = ERC20(currentSwap.sendingAssetId);
receivingAssetId = currentSwap.receivingAssetId;
// check if callTo address is whitelisted
if (
!LibAllowList.contractIsAllowed(currentSwap.callTo) ||
!LibAllowList.selectorIsAllowed(
bytes4(currentSwap.callData[:4])
)
) {
revert ContractCallNotAllowed();
}
// if approveTo address is different to callTo, check if it's whitelisted, too
if (
currentSwap.approveTo != currentSwap.callTo &&
!LibAllowList.contractIsAllowed(currentSwap.approveTo)
) {
revert ContractCallNotAllowed();
}
if (LibAsset.isNativeAsset(sendingAssetId)) {
// Native
// execute the swap
(success, returnData) = currentSwap.callTo.call{
value: currentSwap.fromAmount
}(currentSwap.callData);
if (!success) {
LibUtil.revertWith(returnData);
}
// return any potential leftover sendingAsset tokens
// but only for swaps, not for fee collections (otherwise the whole amount would be returned before the actual swap)
if (sendingAssetId != receivingAssetId)
_returnPositiveSlippageNative(_receiver);
} else {
// ERC20
// check if the current allowance is sufficient
currentAllowance = sendingAsset.allowance(
address(this),
currentSwap.approveTo
);
if (currentAllowance < currentSwap.fromAmount) {
sendingAsset.safeApprove(currentSwap.approveTo, 0);
sendingAsset.safeApprove(
currentSwap.approveTo,
type(uint256).max
);
}
// execute the swap
(success, returnData) = currentSwap.callTo.call(
currentSwap.callData
);
if (!success) {
LibUtil.revertWith(returnData);
}
// return any potential leftover sendingAsset tokens
// but only for swaps, not for fee collections (otherwise the whole amount would be returned before the actual swap)
if (sendingAssetId != receivingAssetId)
_returnPositiveSlippageERC20(sendingAsset, _receiver);
}
// emit AssetSwapped event
// @dev: this event might in some cases emit inaccurate information. e.g. if a token is swapped and this contract already held a balance of the receivingAsset
// then the event will show swapOutputAmount + existingBalance as toAmount. We accept this potential inaccuracy in return for gas savings and may update this
// at a later stage when the described use case becomes more common
emit LibSwap.AssetSwapped(
_transactionId,
currentSwap.callTo,
sendingAssetId,
receivingAssetId,
currentSwap.fromAmount,
LibAsset.isNativeAsset(receivingAssetId)
? address(this).balance
: ERC20(receivingAssetId).balanceOf(address(this)),
block.timestamp
);
unchecked {
++i;
}
}
}
function _transferERC20TokensAndEmitEvent(
bytes32 _transactionId,
string calldata _integrator,
string calldata _referrer,
address payable _receiver,
uint256 _minAmountOut,
LibSwap.SwapData[] calldata _swapData
) private {
// determine the end result of the swap
address finalAssetId = _swapData[_swapData.length - 1]
.receivingAssetId;
uint256 amountReceived = ERC20(finalAssetId).balanceOf(address(this));
// make sure minAmountOut was received
if (amountReceived < _minAmountOut)
revert CumulativeSlippageTooHigh(_minAmountOut, amountReceived);
// transfer to receiver
ERC20(finalAssetId).safeTransfer(_receiver, amountReceived);
// emit event
emit ILiFi.LiFiGenericSwapCompleted(
_transactionId,
_integrator,
_referrer,
_receiver,
_swapData[0].sendingAssetId,
finalAssetId,
_swapData[0].fromAmount,
amountReceived
);
}
function _transferNativeTokensAndEmitEvent(
bytes32 _transactionId,
string calldata _integrator,
string calldata _referrer,
address payable _receiver,
uint256 _minAmountOut,
LibSwap.SwapData[] calldata _swapData
) private {
uint256 amountReceived = address(this).balance;
// make sure minAmountOut was received
if (amountReceived < _minAmountOut)
revert CumulativeSlippageTooHigh(_minAmountOut, amountReceived);
// transfer funds to receiver
// solhint-disable-next-line avoid-low-level-calls
(bool success, ) = _receiver.call{ value: amountReceived }("");
if (!success) {
revert NativeAssetTransferFailed();
}
// emit event
emit ILiFi.LiFiGenericSwapCompleted(
_transactionId,
_integrator,
_referrer,
_receiver,
_swapData[0].sendingAssetId,
NATIVE_ADDRESS,
_swapData[0].fromAmount,
amountReceived
);
}
// returns any unused 'sendingAsset' tokens (=> positive slippage) to the receiver address
function _returnPositiveSlippageERC20(
ERC20 sendingAsset,
address receiver
) private {
// if a balance exists in sendingAsset, it must be positive slippage
if (address(sendingAsset) != NATIVE_ADDRESS) {
uint256 sendingAssetBalance = sendingAsset.balanceOf(
address(this)
);
if (sendingAssetBalance > 0) {
sendingAsset.safeTransfer(receiver, sendingAssetBalance);
}
}
}
// returns any unused native tokens (=> positive slippage) to the receiver address
function _returnPositiveSlippageNative(address receiver) private {
// if a native balance exists in sendingAsset, it must be positive slippage
uint256 nativeBalance = address(this).balance;
if (nativeBalance > 0) {
// solhint-disable-next-line avoid-low-level-calls
(bool success, ) = receiver.call{ value: nativeBalance }("");
if (!success) revert NativeAssetTransferFailed();
}
}
}
// 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;
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
/// @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: MIT
/// @custom:version 1.0.0
pragma solidity ^0.8.17;
import { InvalidContract } from "../Errors/GenericErrors.sol";
/// @title Lib Allow List
/// @author LI.FI (https://li.fi)
/// @notice Library for managing and accessing the conract address allow list
library LibAllowList {
/// Storage ///
bytes32 internal constant NAMESPACE =
keccak256("com.lifi.library.allow.list");
struct AllowListStorage {
mapping(address => bool) allowlist;
mapping(bytes4 => bool) selectorAllowList;
address[] contracts;
}
/// @dev Adds a contract address to the allow list
/// @param _contract the contract address to add
function addAllowedContract(address _contract) internal {
_checkAddress(_contract);
AllowListStorage storage als = _getStorage();
if (als.allowlist[_contract]) return;
als.allowlist[_contract] = true;
als.contracts.push(_contract);
}
/// @dev Checks whether a contract address has been added to the allow list
/// @param _contract the contract address to check
function contractIsAllowed(
address _contract
) internal view returns (bool) {
return _getStorage().allowlist[_contract];
}
/// @dev Remove a contract address from the allow list
/// @param _contract the contract address to remove
function removeAllowedContract(address _contract) internal {
AllowListStorage storage als = _getStorage();
if (!als.allowlist[_contract]) {
return;
}
als.allowlist[_contract] = false;
uint256 length = als.contracts.length;
// Find the contract in the list
for (uint256 i = 0; i < length; i++) {
if (als.contracts[i] == _contract) {
// Move the last element into the place to delete
als.contracts[i] = als.contracts[length - 1];
// Remove the last element
als.contracts.pop();
break;
}
}
}
/// @dev Fetch contract addresses from the allow list
function getAllowedContracts() internal view returns (address[] memory) {
return _getStorage().contracts;
}
/// @dev Add a selector to the allow list
/// @param _selector the selector to add
function addAllowedSelector(bytes4 _selector) internal {
_getStorage().selectorAllowList[_selector] = true;
}
/// @dev Removes a selector from the allow list
/// @param _selector the selector to remove
function removeAllowedSelector(bytes4 _selector) internal {
_getStorage().selectorAllowList[_selector] = false;
}
/// @dev Returns if selector has been added to the allow list
/// @param _selector the selector to check
function selectorIsAllowed(bytes4 _selector) internal view returns (bool) {
return _getStorage().selectorAllowList[_selector];
}
/// @dev Fetch local storage struct
function _getStorage()
internal
pure
returns (AllowListStorage storage als)
{
bytes32 position = NAMESPACE;
// solhint-disable-next-line no-inline-assembly
assembly {
als.slot := position
}
}
/// @dev Contains business logic for validating a contract address.
/// @param _contract address of the dex to check
function _checkAddress(address _contract) private view {
if (_contract == address(0)) revert InvalidContract();
if (_contract.code.length == 0) revert InvalidContract();
}
}
// 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 1.0.2
/// @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.forceApprove(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: 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), from) // Append the "from" argument.
mstore(add(freeMemoryPointer, 36), to) // Append the "to" argument.
mstore(add(freeMemoryPointer, 68), amount) // Append the "amount" argument.
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), to) // Append the "to" argument.
mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument.
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), to) // Append the "to" argument.
mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument.
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");
}
}
// 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/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
// 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: 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);
}
}
// 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);
}
}
}