Contract Name:
CryptoAvatarsExchange
Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
// OpenZeppelin contracts
import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import {IERC20, SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
// CryptoAvatars interfaces
import {ICurrencyManager} from "./interfaces/ICurrencyManager.sol";
import {IExecutionManager} from "./interfaces/IExecutionManager.sol";
import {IExecutionStrategy} from "./interfaces/IExecutionStrategy.sol";
import {IRoyaltyFeeManager} from "./interfaces/IRoyaltyFeeManager.sol";
import {ICryptoAvatarsExchange} from "./interfaces/ICryptoAvatarsExchange.sol";
import {ITransferManagerNFT} from "./interfaces/ITransferManagerNFT.sol";
import {ITransferSelectorNFT} from "./interfaces/ITransferSelectorNFT.sol";
import {ICollectionManager} from "./interfaces/ICollectionManager.sol";
import {IWETH} from "./interfaces/IWETH.sol";
// CryptoAvatars libraries
import {OrderTypes} from "./libraries/OrderTypes.sol";
import {SignatureChecker} from "./libraries/SignatureChecker.sol";
/**
* @title CryptoAvatars
* @notice It is the core contract of the CryptoAvatars exchange.
*/
contract CryptoAvatarsExchange is ICryptoAvatarsExchange, ReentrancyGuard, Ownable {
using SafeERC20 for IERC20;
using OrderTypes for OrderTypes.MakerOrder;
using OrderTypes for OrderTypes.TakerOrder;
address public immutable WETH;
bytes32 public immutable DOMAIN_SEPARATOR;
address public protocolFeeRecipient;
address public signer;
ICurrencyManager public currencyManager;
IExecutionManager public executionManager;
IRoyaltyFeeManager public royaltyFeeManager;
ITransferSelectorNFT public transferSelectorNFT;
ICollectionManager public collectionManager;
mapping(address => uint256) public userMinOrderNonce;
mapping(address => mapping(uint256 => bool)) private _isUserOrderNonceExecutedOrCancelled;
event CancelAllOrders(address indexed user, uint256 newMinNonce);
event CancelMultipleOrders(address indexed user, uint256[] orderNonces);
event NewCurrencyManager(address indexed currencyManager);
event NewExecutionManager(address indexed executionManager);
event NewProtocolFeeRecipient(address indexed protocolFeeRecipient);
event NewRoyaltyFeeManager(address indexed royaltyFeeManager);
event NewCollectionManager(address indexed collectionManager);
event NewTransferSelectorNFT(address indexed transferSelectorNFT);
event RoyaltyPayment(
address indexed collection,
uint256 indexed tokenId,
address indexed royaltyRecipient,
address currency,
uint256 amount
);
event MarketSell(
bytes makerOrder, // maker order data
bytes takerOrder // taker order data
);
/**
* @notice Constructor
* @param _currencyManager currency manager address
* @param _executionManager execution manager address
* @param _royaltyFeeManager royalty fee manager address
* @param _WETH wrapped ether address (for other chains, use wrapped native asset)
* @param _protocolFeeRecipient protocol fee recipient
*/
constructor(
address _currencyManager,
address _executionManager,
address _royaltyFeeManager,
address _collectionManager,
address _WETH,
address _protocolFeeRecipient,
address _signer
) {
// Calculate the domain separator
DOMAIN_SEPARATOR = keccak256(
abi.encode(
0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f, // keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)")
0x479e4b32420d5d35c74f62189f17325d7fd3b51ff82b6be4bcab394dc45ea1d9, // keccak256("CryptoAvatars")
0xc89efdaa54c0f20c7adf612882df0950f5a951637e0307cdcb4c672f298b8bc6, // keccak256(bytes("1")) for versionId = 1
block.chainid,
address(this)
)
);
currencyManager = ICurrencyManager(_currencyManager);
executionManager = IExecutionManager(_executionManager);
royaltyFeeManager = IRoyaltyFeeManager(_royaltyFeeManager);
collectionManager = ICollectionManager(_collectionManager);
WETH = _WETH;
protocolFeeRecipient = _protocolFeeRecipient;
signer = _signer;
}
/**
* @notice Cancel all pending orders for a sender
* @param minNonce minimum user nonce
*/
function cancelAllOrdersForSender(uint256 minNonce) external {
require(minNonce > userMinOrderNonce[msg.sender], "Cancel: Order nonce lower than current");
require(minNonce < userMinOrderNonce[msg.sender] + 500000, "Cancel: Cannot cancel more orders");
userMinOrderNonce[msg.sender] = minNonce;
emit CancelAllOrders(msg.sender, minNonce);
}
/**
* @notice Cancel maker orders
* @param orderNonces array of order nonces
*/
function cancelMultipleMakerOrders(uint256[] calldata orderNonces) external {
require(orderNonces.length > 0, "Cancel: Cannot be empty");
for (uint256 i = 0; i < orderNonces.length; i++) {
require(orderNonces[i] >= userMinOrderNonce[msg.sender], "Cancel: Order nonce lower than current");
_isUserOrderNonceExecutedOrCancelled[msg.sender][orderNonces[i]] = true;
}
emit CancelMultipleOrders(msg.sender, orderNonces);
}
/**
* @notice Match ask with a taker bid order using ETH
* @param takerBid taker bid order
* @param makerAsk maker ask order
*/
function matchAskWithTakerBidUsingETHAndWETH(
OrderTypes.TakerOrder calldata takerBid,
OrderTypes.MakerOrder calldata makerAsk
) external payable override nonReentrant {
require((makerAsk.isOrderAsk) && (!takerBid.isOrderAsk), "Order: Wrong sides");
require(makerAsk.currency == WETH, "Order: Currency must be WETH");
require(msg.sender == takerBid.taker, "Order: Taker must be the sender");
// If not enough ETH to cover the price, use WETH
if (takerBid.price > msg.value) {
IERC20(WETH).safeTransferFrom(msg.sender, address(this), (takerBid.price - msg.value));
} else {
require(takerBid.price == msg.value, "Order: Msg.value too high");
}
// Wrap ETH sent to this contract
IWETH(WETH).deposit{value: msg.value}();
// Check maker ask and taker bid orders
_validateOrder(makerAsk, takerBid);
// Retrieve execution parameters
(bool isExecutionValid, uint256 tokenId, uint256 amount) = IExecutionStrategy(makerAsk.strategy)
.canExecuteTakerBid(takerBid, makerAsk);
require(isExecutionValid, "Strategy: Execution invalid");
// Update maker ask order status to true (prevents replay)
_isUserOrderNonceExecutedOrCancelled[makerAsk.signer][makerAsk.nonce] = true;
// Execution part 1/2
_transferFeesAndFundsWithWETH(
makerAsk,
takerBid,
makerAsk.signer
);
// Execution part 2/2
_transferNonFungibleToken(makerAsk.collection, makerAsk.signer, takerBid.taker, tokenId, amount);
// Emit event
emit MarketSell(abi.encode(makerAsk), abi.encode(takerBid));
}
/**
* @notice Match a takerBid with a matchAsk
* @param takerBid taker bid order
* @param makerAsk maker ask order
*/
function matchAskWithTakerBid(OrderTypes.TakerOrder calldata takerBid, OrderTypes.MakerOrder calldata makerAsk)
external
override
nonReentrant
{
require((makerAsk.isOrderAsk) && (!takerBid.isOrderAsk), "Order: Wrong sides");
require(msg.sender == takerBid.taker, "Order: Taker must be the sender");
// Check the maker ask order
_validateOrder(makerAsk, takerBid);
(bool isExecutionValid, uint256 tokenId, uint256 amount) = IExecutionStrategy(makerAsk.strategy)
.canExecuteTakerBid(takerBid, makerAsk);
require(isExecutionValid, "Strategy: Execution invalid");
// Update maker ask order status to true (prevents replay)
_isUserOrderNonceExecutedOrCancelled[makerAsk.signer][makerAsk.nonce] = true;
// Execution part 1/2
_transferFeesAndFunds(makerAsk, takerBid, takerBid.taker, makerAsk.signer);
// Execution part 2/2
_transferNonFungibleToken(makerAsk.collection, makerAsk.signer, takerBid.taker, tokenId, amount);
// Emit event
emit MarketSell(abi.encode(makerAsk), abi.encode(takerBid));
}
/**
* @notice Match a takerAsk with a makerBid
* @param takerAsk taker ask order
* @param makerBid maker bid order
*/
function matchBidWithTakerAsk(OrderTypes.TakerOrder calldata takerAsk, OrderTypes.MakerOrder calldata makerBid)
external
override
nonReentrant
{
require((!makerBid.isOrderAsk) && (takerAsk.isOrderAsk), "Order: Wrong sides");
require(msg.sender == takerAsk.taker, "Order: Taker must be the sender");
// Check the maker bid order
_validateOrder(makerBid, takerAsk);
(bool isExecutionValid, uint256 tokenId, uint256 amount) = IExecutionStrategy(makerBid.strategy)
.canExecuteTakerAsk(takerAsk, makerBid);
require(isExecutionValid, "Strategy: Execution invalid");
// Update maker bid order status to true (prevents replay)
_isUserOrderNonceExecutedOrCancelled[makerBid.signer][makerBid.nonce] = true;
// Execution part 1/2
_transferNonFungibleToken(makerBid.collection, takerAsk.taker, makerBid.signer, tokenId, amount);
// Execution part 2/2
_transferFeesAndFunds(makerBid, takerAsk, makerBid.signer, takerAsk.taker);
// Emit event
emit MarketSell(abi.encode(makerBid), abi.encode(takerAsk));
}
/**
* @notice Update signer
* @param _signer new marketplace signer
*/
function updateSigner(address _signer) external onlyOwner {
require(_signer != address(0), "Owner: Cannot be null address");
signer = _signer;
}
/**
* @notice Update currency manager
* @param _currencyManager new currency manager address
*/
function updateCurrencyManager(address _currencyManager) external onlyOwner {
require(_currencyManager != address(0), "Owner: Cannot be null address");
currencyManager = ICurrencyManager(_currencyManager);
emit NewCurrencyManager(_currencyManager);
}
/**
* @notice Update execution manager
* @param _executionManager new execution manager address
*/
function updateExecutionManager(address _executionManager) external onlyOwner {
require(_executionManager != address(0), "Owner: Cannot be null address");
executionManager = IExecutionManager(_executionManager);
emit NewExecutionManager(_executionManager);
}
/**
* @notice Update collection manager
* @param _collectionManager new collection manager address
*/
function updateCollectionManager(address _collectionManager) external onlyOwner {
require(_collectionManager != address(0), "Owner: Cannot be null address");
collectionManager = ICollectionManager(_collectionManager);
emit NewCollectionManager(_collectionManager);
}
/**
* @notice Update protocol fee and recipient
* @param _protocolFeeRecipient new recipient for protocol fees
*/
function updateProtocolFeeRecipient(address _protocolFeeRecipient) external onlyOwner {
protocolFeeRecipient = _protocolFeeRecipient;
emit NewProtocolFeeRecipient(_protocolFeeRecipient);
}
/**
* @notice Update royalty fee manager
* @param _royaltyFeeManager new fee manager address
*/
function updateRoyaltyFeeManager(address _royaltyFeeManager) external onlyOwner {
require(_royaltyFeeManager != address(0), "Owner: Cannot be null address");
royaltyFeeManager = IRoyaltyFeeManager(_royaltyFeeManager);
emit NewRoyaltyFeeManager(_royaltyFeeManager);
}
/**
* @notice Update transfer selector NFT
* @param _transferSelectorNFT new transfer selector address
*/
function updateTransferSelectorNFT(address _transferSelectorNFT) external onlyOwner {
require(_transferSelectorNFT != address(0), "Owner: Cannot be null address");
transferSelectorNFT = ITransferSelectorNFT(_transferSelectorNFT);
emit NewTransferSelectorNFT(_transferSelectorNFT);
}
/**
* @notice Check whether user order nonce is executed or cancelled
* @param user address of user
* @param orderNonce nonce of the order
*/
function isUserOrderNonceExecutedOrCancelled(address user, uint256 orderNonce) external view returns (bool) {
return _isUserOrderNonceExecutedOrCancelled[user][orderNonce];
}
/**
* @notice Transfer fees and funds to royalty recipient, protocol, and seller
* @param takerOrder taker order
* @param makerOrder maker order
* @param from _msgSender()
*/
function _transferFeesAndFunds(
OrderTypes.MakerOrder calldata makerOrder,
OrderTypes.TakerOrder calldata takerOrder,
address from,
address to
) internal {
// Initialize the final amount that is transferred to seller
uint256 finalSellerAmount = makerOrder.price;
// 1. Protocol fee
{
uint256 protocolFeeAmount = _calculateProtocolFee(makerOrder.strategy, makerOrder.price);
// Check if the protocol fee is different than 0 for this strategy
if ((protocolFeeRecipient != address(0)) && (protocolFeeAmount != 0)) {
IERC20(makerOrder.currency).safeTransferFrom(from, protocolFeeRecipient, protocolFeeAmount);
finalSellerAmount -= protocolFeeAmount;
}
}
// 2. Royalty fee
{
if(!isZeroBytes(takerOrder.dataCryptoAvatars)) { // Is CryptoAvatars, pay a fee to the avatar creator
(address creator , uint256 royaltyFee) = abi.decode(takerOrder.dataCryptoAvatars, (address, uint256));
uint256 royaltyCreatorFeeAmount = (makerOrder.price * royaltyFee) / 10000 ;
if ((creator != address(0)) && (royaltyCreatorFeeAmount != 0)) {
IERC20(makerOrder.currency).safeTransferFrom(from, creator, royaltyCreatorFeeAmount);
finalSellerAmount -= royaltyCreatorFeeAmount;
}
}
else if(!isZeroBytes(takerOrder.dataRemix)) { // Is Remix, pay a fee to the remix creator and to the collection owner
(address creatorRemix, address ownerRemix) = abi.decode(takerOrder.dataRemix, (address, address));
uint256 royaltyCreatorFee = royaltyFeeManager.getRemixCreatorRoyaltyFee();
uint256 royaltyOwnerFee = royaltyFeeManager.getRemixOwnerRoyaltyFee();
uint256 royaltyCreatorFeeAmount = (makerOrder.price * royaltyCreatorFee) / 10000 ;
uint256 royaltyOwnerFeeAmount = (makerOrder.price * royaltyOwnerFee) / 10000 ;
IERC20(makerOrder.currency).safeTransferFrom(from, creatorRemix, royaltyCreatorFeeAmount);
IERC20(makerOrder.currency).safeTransferFrom(from, ownerRemix, royaltyOwnerFeeAmount);
finalSellerAmount -= royaltyCreatorFeeAmount + royaltyOwnerFeeAmount;
}
else { // It is a non CA collection, pay a fee to the collection owner
(address royaltyFeeRecipient, uint256 royaltyFeeAmount) = royaltyFeeManager
.calculateRoyaltyFeeAndGetRecipient(makerOrder.collection, makerOrder.tokenId, makerOrder.price);
// Check if there is a royalty fee and that it is different to 0
if ((royaltyFeeRecipient != address(0)) && (royaltyFeeAmount != 0)) {
IERC20(makerOrder.currency).safeTransferFrom(from, royaltyFeeRecipient, royaltyFeeAmount);
finalSellerAmount -= royaltyFeeAmount;
emit RoyaltyPayment(makerOrder.collection, makerOrder.tokenId, royaltyFeeRecipient, makerOrder.currency, royaltyFeeAmount);
}
}
}
require((finalSellerAmount * 10000) >= (makerOrder.minPercentageToAsk * makerOrder.price), "Fees: Higher than expected");
// 3. Transfer final amount (post-fees) to seller
{
IERC20(makerOrder.currency).safeTransferFrom(from, to, finalSellerAmount);
}
}
/**
* @notice Transfer fees and funds to royalty recipient, protocol, and seller
* @param makerOrder maker order
* @param takerOrder taker order
*/
function _transferFeesAndFundsWithWETH(
OrderTypes.MakerOrder calldata makerOrder,
OrderTypes.TakerOrder calldata takerOrder,
address to
) internal {
// Initialize the final amount that is transferred to seller
uint256 finalSellerAmount = makerOrder.price;
// 1. Protocol fee
{
uint256 protocolFeeAmount = _calculateProtocolFee(makerOrder.strategy, makerOrder.price);
// Check if the protocol fee is different than 0 for this strategy
if ((protocolFeeRecipient != address(0)) && (protocolFeeAmount != 0)) {
IERC20(WETH).safeTransfer(protocolFeeRecipient, protocolFeeAmount);
finalSellerAmount -= protocolFeeAmount;
}
}
// 2. Royalty fee
{
if(!isZeroBytes(takerOrder.dataCryptoAvatars)) { // Is CryptoAvatars, pay a fee to the avatar creator
(address creator , uint256 royaltyFee) = abi.decode(takerOrder.dataCryptoAvatars, (address, uint256));
uint256 royaltyCreatorFeeAmount = (makerOrder.price * royaltyFee) / 10000 ;
if ((creator != address(0)) && (royaltyCreatorFeeAmount != 0)) {
IERC20(WETH).safeTransfer(creator, royaltyCreatorFeeAmount);
finalSellerAmount -= royaltyCreatorFeeAmount;
}
}
else if(!isZeroBytes(takerOrder.dataRemix)) { // Is Remix, pay a fee to the remix creator and to the collection owner
(address creatorRemix, address ownerRemix) = abi.decode(takerOrder.dataRemix, (address, address));
uint256 royaltyCreatorFee = royaltyFeeManager.getRemixCreatorRoyaltyFee();
uint256 royaltyOwnerFee = royaltyFeeManager.getRemixOwnerRoyaltyFee();
uint256 royaltyCreatorFeeAmount = (makerOrder.price * royaltyCreatorFee) / 10000 ;
uint256 royaltyOwnerFeeAmount = (makerOrder.price * royaltyOwnerFee) / 10000 ;
IERC20(WETH).safeTransfer(creatorRemix, royaltyCreatorFeeAmount);
IERC20(WETH).safeTransfer(ownerRemix, royaltyOwnerFeeAmount);
finalSellerAmount -= royaltyCreatorFeeAmount + royaltyOwnerFeeAmount;
}
else { // It is a non CA collection, pay a fee to the collection owner
(address royaltyFeeRecipient, uint256 royaltyFeeAmount) = royaltyFeeManager
.calculateRoyaltyFeeAndGetRecipient(makerOrder.collection, makerOrder.tokenId, makerOrder.price);
// Check if there is a royalty fee and that it is different to 0
if ((royaltyFeeRecipient != address(0)) && (royaltyFeeAmount != 0)) {
IERC20(WETH).safeTransfer(royaltyFeeRecipient, royaltyFeeAmount);
finalSellerAmount -= royaltyFeeAmount;
emit RoyaltyPayment(makerOrder.collection, makerOrder.tokenId, royaltyFeeRecipient, WETH, royaltyFeeAmount);
}
}
}
require((finalSellerAmount * 10000) >= (makerOrder.minPercentageToAsk * makerOrder.price), "Fees: Higher than expected");
// 3. Transfer final amount (post-fees) to seller
{
IERC20(WETH).safeTransfer(to, finalSellerAmount);
}
}
/**
* @notice Transfer NFT
* @param collection address of the token collection
* @param from address of the sender
* @param to address of the recipient
* @param tokenId tokenId
* @param amount amount of tokens (1 for ERC721, 1+ for ERC1155)
* @dev For ERC721, amount is not used
*/
function _transferNonFungibleToken(
address collection,
address from,
address to,
uint256 tokenId,
uint256 amount
) internal {
// Retrieve the transfer manager address
address transferManager = transferSelectorNFT.checkTransferManagerForToken(collection);
// If no transfer manager found, it returns address(0)
require(transferManager != address(0), "Transfer: No NFT transfer manager available");
// If one is found, transfer the token
ITransferManagerNFT(transferManager).transferNonFungibleToken(collection, from, to, tokenId, amount);
}
/**
* @notice Calculate protocol fee for an execution strategy
* @param executionStrategy strategy
* @param amount amount to transfer
*/
function _calculateProtocolFee(address executionStrategy, uint256 amount) internal view returns (uint256) {
uint256 protocolFee = IExecutionStrategy(executionStrategy).viewProtocolFee();
return (protocolFee * amount) / 10000;
}
/**
* @notice Verify the validity of the maker order and the taker order
* @param makerOrder maker order
* @param takerOrder taker order
*/
function _validateOrder(OrderTypes.MakerOrder calldata makerOrder,
OrderTypes.TakerOrder calldata takerOrder) internal view {
// Verify whether order nonce has expired
require(
(!_isUserOrderNonceExecutedOrCancelled[makerOrder.signer][makerOrder.nonce]) &&
(makerOrder.nonce >= userMinOrderNonce[makerOrder.signer]),
"Order: Matching order expired"
);
// Verify the signer is not address(0)
require(makerOrder.signer != address(0), "Order: Invalid signer");
// Verify the amount is not 0
require(makerOrder.amount > 0, "Order: Amount cannot be 0");
// Verify signature max valid time
require(block.timestamp<=takerOrder.maxValidTime, "Order: Invalid signature");
bytes32 makerOrderHash = makerOrder.hashMakerOrder();
// Verify the validity of the signatures
// Verify makerOrder signature
require(
SignatureChecker.verifySignature712(
makerOrderHash,
makerOrder.signer,
makerOrder.v,
makerOrder.r,
makerOrder.s,
DOMAIN_SEPARATOR
),
"MakerOrder Signature: Invalid"
);
bytes32 takerOrderHash = takerOrder.hashTakerOrder();
// Verify takerOrder signature
require(
SignatureChecker.verifySignature191(
takerOrderHash,
signer,
takerOrder.v,
takerOrder.r,
takerOrder.s
),
"TakerOrder Signature: Invalid"
);
// Verify whether the currency is whitelisted
require(currencyManager.isCurrencyWhitelisted(makerOrder.currency), "Currency: Not whitelisted");
// Verify whether strategy can be executed
require(executionManager.isStrategyWhitelisted(makerOrder.strategy), "Strategy: Not whitelisted");
// Verify whether the collection is whitelisted
require(collectionManager.isCollectionWhitelisted(makerOrder.collection),"Collection: Not whitelisted");
}
function isZeroBytes(bytes calldata data) public pure returns (bool) {
for (uint256 i = 0; i < data.length; i++) {
if (data[i] != 0) {
return false;
}
}
return true;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface ICurrencyManager {
function addCurrency(address currency) external;
function removeCurrency(address currency) external;
function isCurrencyWhitelisted(address currency) external view returns (bool);
function viewWhitelistedCurrencies(uint256 cursor, uint256 size) external view returns (address[] memory, uint256);
function viewCountWhitelistedCurrencies() external view returns (uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IRoyaltyFeeManager {
function calculateRoyaltyFeeAndGetRecipient(
address collection,
uint256 tokenId,
uint256 amount
) external view returns (address, uint256);
function getRemixCreatorRoyaltyFee()external view returns(uint256);
function getRemixOwnerRoyaltyFee()external view returns(uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IExecutionManager {
function addStrategy(address strategy) external;
function removeStrategy(address strategy) external;
function isStrategyWhitelisted(address strategy) external view returns (bool);
function viewWhitelistedStrategies(uint256 cursor, uint256 size) external view returns (address[] memory, uint256);
function viewCountWhitelistedStrategies() external view returns (uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {OrderTypes} from "../libraries/OrderTypes.sol";
interface ICryptoAvatarsExchange {
function matchAskWithTakerBidUsingETHAndWETH(
OrderTypes.TakerOrder calldata takerBid,
OrderTypes.MakerOrder calldata makerAsk
) external payable;
function matchAskWithTakerBid(OrderTypes.TakerOrder calldata takerBid, OrderTypes.MakerOrder calldata makerAsk)
external;
function matchBidWithTakerAsk(OrderTypes.TakerOrder calldata takerAsk, OrderTypes.MakerOrder calldata makerBid)
external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {OrderTypes} from "../libraries/OrderTypes.sol";
interface IExecutionStrategy {
function canExecuteTakerAsk(OrderTypes.TakerOrder calldata takerAsk, OrderTypes.MakerOrder calldata makerBid)
external
view
returns (
bool,
uint256,
uint256
);
function canExecuteTakerBid(OrderTypes.TakerOrder calldata takerBid, OrderTypes.MakerOrder calldata makerAsk)
external
view
returns (
bool,
uint256,
uint256
);
function viewProtocolFee() external view returns (uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface ITransferSelectorNFT {
function checkTransferManagerForToken(address collection) external view returns (address);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface ITransferManagerNFT {
function transferNonFungibleToken(
address collection,
address from,
address to,
uint256 tokenId,
uint256 amount
) external;
}
// SPDX-License-Identifier: GNU
pragma solidity >=0.5.0;
interface IWETH {
function deposit() external payable;
function transfer(address to, uint256 value) external returns (bool);
function withdraw(uint256) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface ICollectionManager {
function addCollection(address collection) external;
function removeCollection(address collection) external;
function isCollectionWhitelisted(address collection) external view returns (bool);
function viewWhitelistedCollections(uint256 cursor, uint256 size) external view returns (address[] memory, uint256);
function viewCountWhitelistedCollections() external view returns (uint256);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import {Address} from "@openzeppelin/contracts/utils/Address.sol";
import {IERC1271} from "@openzeppelin/contracts/interfaces/IERC1271.sol";
/**
* @title SignatureChecker
* @notice This library allows verification of signatures for both EOAs and contracts.
*/
library SignatureChecker {
/**
* @notice Recovers the signer of a signature (for EOA)
* @param hash the hash containing the signed mesage
* @param v parameter (27 or 28). This prevents maleability since the public key recovery equation has two possible solutions.
* @param r parameter
* @param s parameter
*/
function recover(
bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internal pure returns (address) {
// https://ethereum.stackexchange.com/questions/83174/is-it-best-practice-to-check-signature-malleability-in-ecrecover
// https://crypto.iacr.org/2019/affevents/wac/medias/Heninger-BiasedNonceSense.pdf
require(
uint256(s) <=
0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,
"Signature: Invalid s parameter"
);
require(v == 27 || v == 28, "Signature: Invalid v parameter");
// If the signature is valid (and not malleable), return the signer address
address signer = ecrecover(hash, v, r, s);
require(signer != address(0), "Signature: Invalid signer");
return signer;
}
/**
* @notice Returns whether the signer matches the signed message
* @param hash the hash containing the signed mesage
* @param signer the signer address to confirm message validity
* @param v parameter (27 or 28)
* @param r parameter
* @param s parameter
* @param domainSeparator paramer to prevent signature being executed in other chains and environments
* @return true --> if valid // false --> if invalid
* https://eips.ethereum.org/EIPS/eip-712#specification
*/
function verifySignature712(
bytes32 hash,
address signer,
uint8 v,
bytes32 r,
bytes32 s,
bytes32 domainSeparator
) internal view returns (bool) {
bytes32 digest = keccak256(
abi.encodePacked("\x19\x01", domainSeparator, hash)
);
if (Address.isContract(signer)) {
// 0x1626ba7e is the interfaceId for signature contracts (see IERC1271)
return
IERC1271(signer).isValidSignature(
digest,
abi.encodePacked(r, s, v)
) == 0x1626ba7e;
} else {
return recover(digest, v, r, s) == signer;
}
}
/**
* @notice Returns whether the signer matches the signed message
* @param hash the hash containing the signed mesage
* @param signer the signer address to confirm message validity
* @param v parameter (27 or 28)
* @param r parameter
* @param s parameter
* @return true --> if valid // false --> if invalid
* https://eips.ethereum.org/EIPS/eip-191#specification
*/
function verifySignature191(
bytes32 hash,
address signer,
uint8 v,
bytes32 r,
bytes32 s
) internal pure returns (bool) {
bytes32 messageHash = keccak256(
abi.encodePacked("\x19Ethereum Signed Message:\n32", hash)
);
address recovered = recover(messageHash, v, r, s);
return recovered == signer;
}
function splitSignature(
bytes memory sig
) internal pure returns (bytes32 r, bytes32 s, uint8 v) {
require(sig.length == 65, "invalid signature length");
assembly {
r := mload(add(sig, 32))
s := mload(add(sig, 64))
v := byte(0, mload(add(sig, 96)))
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
* @title OrderTypes
* @notice This library contains order types for the CryptoAvatars exchange.
*/
library OrderTypes {
// keccak256("MakerOrder(bool isOrderAsk,address signer,address collection,uint256 price,uint256 tokenId,uint256 amount,address strategy,address currency,uint256 nonce,uint256 startTime,uint256 endTime,uint256 minPercentageToAsk,bytes params)")
bytes32 internal constant MAKER_ORDER_HASH = 0x40261ade532fa1d2c7293df30aaadb9b3c616fae525a0b56d3d411c841a85028;
//keccak256("TakerOrder(bool isOrderAsk,address taker,address signer,uint256 price,uint256 tokenId,uint256 maxValidTime,uint256 minPercentageToAsk,bytes params,bytes dataCryptoAvatars,bytes dataRemix)")
bytes32 internal constant TAKER_ORDER_HASH = 0x52899feb3ddfece805ec742fd953f7c2d538f6a548044216a6b8db2598b449d9;
struct MakerOrder {
bool isOrderAsk; // true --> ask / false --> bid
address signer; // signer of the maker order
address collection; // collection address
uint256 price; // price (used as )
uint256 tokenId; // id of the token
uint256 amount; // amount of tokens to sell/purchase (must be 1 for ERC721, 1+ for ERC1155)
address strategy; // strategy for trade execution (e.g., DutchAuction, StandardSaleForFixedPrice)
address currency; // currency (e.g., WETH)
uint256 nonce; // order nonce (must be unique unless new maker order is meant to override existing one e.g., lower ask price)
uint256 startTime; // startTime in timestamp
uint256 endTime; // endTime in timestamp
uint256 minPercentageToAsk; // slippage protection (9000 --> 90% of the final price must return to ask)
bytes params; // additional parameters
uint8 v; // v: parameter (27 or 28)
bytes32 r; // r: parameter
bytes32 s; // s: parameter
}
struct TakerOrder {
bool isOrderAsk; // true --> ask / false --> bid
address taker; // msg.sender
address signer;
uint256 price; // final price for the purchase
uint256 tokenId;
uint256 maxValidTime; // validTime in timestamp
uint256 minPercentageToAsk; // // slippage protection (9000 --> 90% of the final price must return to ask)
bytes params; // other params (e.g., tokenId)
bytes dataCryptoAvatars; // data for CryptoAvatars NFT
bytes dataRemix; // check if the NFT is a remix and if so, the creator and the owner of the parent remix avatar for royalties
uint8 v; // v: parameter (27 or 28)
bytes32 r; // r: parameter
bytes32 s; // s: parameter
}
function hashMakerOrder(MakerOrder memory makerOrder) internal pure returns (bytes32) {
return
keccak256(
abi.encode(
MAKER_ORDER_HASH,
makerOrder.isOrderAsk,
makerOrder.signer,
makerOrder.collection,
makerOrder.price,
makerOrder.tokenId,
makerOrder.amount,
makerOrder.strategy,
makerOrder.currency,
makerOrder.nonce,
makerOrder.startTime,
makerOrder.endTime,
makerOrder.minPercentageToAsk,
keccak256(makerOrder.params)
)
);
}
// keccak256("TakerOrder(bool isOrderAsk,address taker,uint256 price,uint256 tokenId,uint256 minPercentageToAsk,bytes params,uint256 validTime))
function hashTakerOrder(TakerOrder memory takerOrder) internal view returns (bytes32) {
return
keccak256(
abi.encode(
TAKER_ORDER_HASH,
block.chainid,
takerOrder.isOrderAsk,
takerOrder.taker,
takerOrder.signer,
takerOrder.price,
takerOrder.tokenId,
takerOrder.maxValidTime,
takerOrder.minPercentageToAsk,
keccak256(takerOrder.params),
keccak256(takerOrder.dataCryptoAvatars),
keccak256(takerOrder.dataRemix)
)
);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
pragma solidity ^0.8.0;
/**
* @dev Contract module that helps prevent reentrant calls to a function.
*
* Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
* available, which can be applied to functions to make sure there are no nested
* (reentrant) calls to them.
*
* Note that because there is a single `nonReentrant` guard, functions marked as
* `nonReentrant` may not call one another. This can be worked around by making
* those functions `private`, and then adding `external` `nonReentrant` entry
* points to them.
*
* TIP: If you would like to learn more about reentrancy and alternative ways
* to protect against it, check out our blog post
* https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
*/
abstract contract ReentrancyGuard {
// Booleans are more expensive than uint256 or any type that takes up a full
// word because each write operation emits an extra SLOAD to first read the
// slot's contents, replace the bits taken up by the boolean, and then write
// back. This is the compiler's defense against contract upgrades and
// pointer aliasing, and it cannot be disabled.
// The values being non-zero value makes deployment a bit more expensive,
// but in exchange the refund on every call to nonReentrant will be lower in
// amount. Since refunds are capped to a percentage of the total
// transaction's gas, it is best to keep them low in cases like this one, to
// increase the likelihood of the full refund coming into effect.
uint256 private constant _NOT_ENTERED = 1;
uint256 private constant _ENTERED = 2;
uint256 private _status;
constructor() {
_status = _NOT_ENTERED;
}
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* Calling a `nonReentrant` function from another `nonReentrant`
* function is not supported. It is possible to prevent this from happening
* by making the `nonReentrant` function external, and making it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
// On the first call to nonReentrant, _notEntered will be true
require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
// Any calls to nonReentrant after this point will fail
_status = _ENTERED;
_;
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = _NOT_ENTERED;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor() {
_transferOwnership(_msgSender());
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
_checkOwner();
_;
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if the sender is not the owner.
*/
function _checkOwner() internal view virtual {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
import "../extensions/draft-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;
function safeTransfer(
IERC20 token,
address to,
uint256 value
) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
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));
}
function safeIncreaseAllowance(
IERC20 token,
address spender,
uint256 value
) internal {
uint256 newAllowance = token.allowance(address(this), spender) + value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
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");
uint256 newAllowance = oldAllowance - value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
}
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");
if (returndata.length > 0) {
// Return data is optional
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (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
* ====
*
* [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://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value
) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
(bool success, bytes memory returndata) = target.call{value: value}(data);
return verifyCallResult(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) {
require(isContract(target), "Address: static call to non-contract");
(bool success, bytes memory returndata) = target.staticcall(data);
return verifyCallResult(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) {
require(isContract(target), "Address: delegate call to non-contract");
(bool success, bytes memory returndata) = target.delegatecall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason 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 {
// 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 v4.4.1 (interfaces/IERC1271.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC1271 standard signature validation method for
* contracts as defined in https://eips.ethereum.org/EIPS/eip-1271[ERC-1271].
*
* _Available since v4.1._
*/
interface IERC1271 {
/**
* @dev Should return whether the signature provided is valid for the provided data
* @param hash Hash of the data to be signed
* @param signature Signature byte array associated with _data
*/
function isValidSignature(bytes32 hash, bytes memory signature) external view returns (bytes4 magicValue);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (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 v4.4.1 (token/ERC20/extensions/draft-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);
}