Contract Source Code:
// SPDX-License-Identifier: MIT
import "./ONFT721.sol";
pragma solidity ^0.8.18;
/// @title Interface of Whale, which follows the UniversalONFT standard
contract Whale is ONFT721 {
uint256 public fee = 0.0001 ether;
uint256 public nextMintId;
uint256 public maxMintId;
mapping(address => uint256[]) public userNFTIds;
/// @notice Constructor for the UniversalONFT
/// @param _layerZeroEndpoint handles message transmission across chains
/// @param _startMintId the starting mint number on this chain
/// @param _endMintId the max number of mints on this chain
constructor(
uint256 _minGasToTransfer,
address _layerZeroEndpoint,
uint256 _startMintId,
uint256 _endMintId
) ONFT721("Whale ONFT", "WHL", _minGasToTransfer, _layerZeroEndpoint) {
nextMintId = _startMintId;
maxMintId = _endMintId;
}
function mint() external payable {
require(msg.value >= fee, "Not enough ether sent");
require(nextMintId <= maxMintId, "Too many, bruv");
uint256 newId = nextMintId;
nextMintId++;
userNFTIds[msg.sender].push(newId);
_safeMint(msg.sender, newId);
}
function getUserNFTIds(address user) external view returns (uint256[] memory) {
return userNFTIds[user];
}
function estimateGasBridgeFee(
uint16 _dstChainId,
bool _useZro,
bytes memory _adapterParams
) public view virtual returns (uint256 nativeFee, uint256 zroFee) {
bytes memory payload = abi.encode(msg.sender, 0);
return lzEndpoint.estimateFees(_dstChainId, payable(address(this)), payload, _useZro, _adapterParams);
}
function bridgeGas(
uint16 _dstChainId,
address _zroPaymentAddress,
bytes memory _adapterParams
) public payable {
_checkGasLimit(_dstChainId, FUNCTION_TYPE_SEND, _adapterParams, dstChainIdToTransferGas[_dstChainId]);
_lzSend(
_dstChainId,
abi.encode(msg.sender, 0),
payable(address(this)),
_zroPaymentAddress,
_adapterParams,
msg.value
);
}
function tokenURI(uint256 id) public view virtual override returns (string memory) {
return string(abi.encodePacked(_baseURI(), Strings.toString(id), ".json"));
}
function _baseURI() internal pure override returns (string memory) {
return "ipfs://bafybeidbm7djh7bzumrt76xlj5hfqkzh5sqtu44gmgkxcd4mkxmc24igva/";
}
function withdraw() public payable onlyOwner {
(bool success, ) = payable(msg.sender).call{value: address(this).balance}("");
require(success);
}
function setFee(uint256 _fee) external onlyOwner {
fee = _fee;
}
}
// SPDX-License-Identifier: MIT
import "./ONFT721Core.sol";
import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "../contracts/interfaces/IONFT721.sol";
pragma solidity ^0.8.18;
// NOTE: this ONFT contract has no public minting logic.
// must implement your own minting logic in child classes
contract ONFT721 is ONFT721Core, ERC721, IONFT721 {
constructor(
string memory _name,
string memory _symbol,
uint256 _minGasToTransfer,
address _lzEndpoint
) ERC721(_name, _symbol) ONFT721Core(_minGasToTransfer, _lzEndpoint) {}
function supportsInterface(bytes4 interfaceId)
public
view
virtual
override(ONFT721Core, ERC721, IERC165)
returns (bool)
{
return interfaceId == type(IONFT721).interfaceId || super.supportsInterface(interfaceId);
}
function _debitFrom(
address _from,
uint16,
bytes memory,
uint256 _tokenId
) internal virtual override {
require(_isApprovedOrOwner(_msgSender(), _tokenId), "ONFT721: send caller is not owner nor approved");
require(ERC721.ownerOf(_tokenId) == _from, "ONFT721: send from incorrect owner");
_transfer(_from, address(this), _tokenId);
}
function _creditTo(
uint16,
address _toAddress,
uint256 _tokenId
) internal virtual override {
require(!_exists(_tokenId) || (_exists(_tokenId) && ERC721.ownerOf(_tokenId) == address(this)));
if (!_exists(_tokenId)) {
_safeMint(_toAddress, _tokenId);
} else {
_transfer(address(this), _toAddress, _tokenId);
}
}
}
// SPDX-License-Identifier: MIT
import "@layerzerolabs/solidity-examples/contracts/lzApp/NonblockingLzApp.sol";
import "@openzeppelin/contracts/utils/introspection/ERC165.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "../contracts/interfaces/IONFT721Core.sol";
pragma solidity ^0.8.18;
abstract contract ONFT721Core is NonblockingLzApp, ERC165, ReentrancyGuard, IONFT721Core {
uint16 public constant FUNCTION_TYPE_SEND = 1;
struct StoredCredit {
uint16 srcChainId;
address toAddress;
uint256 index; // which index of the tokenIds remain
bool creditsRemain;
}
uint256 public minGasToTransferAndStore; // min amount of gas required to transfer, and also store the payload
mapping(uint16 => uint256) public dstChainIdToBatchLimit;
mapping(uint16 => uint256) public dstChainIdToTransferGas; // per transfer amount of gas required to mint/transfer on the dst
mapping(bytes32 => StoredCredit) public storedCredits;
constructor(uint256 _minGasToTransferAndStore, address _lzEndpoint) NonblockingLzApp(_lzEndpoint) {
require(_minGasToTransferAndStore > 0, "minGasToTransferAndStore must be > 0");
minGasToTransferAndStore = _minGasToTransferAndStore;
}
function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
return interfaceId == type(IONFT721Core).interfaceId || super.supportsInterface(interfaceId);
}
function estimateSendFee(
uint16 _dstChainId,
bytes memory _toAddress,
uint256 _tokenId,
bool _useZro,
bytes memory _adapterParams
) public view virtual override returns (uint256 nativeFee, uint256 zroFee) {
return estimateSendBatchFee(_dstChainId, _toAddress, _toSingletonArray(_tokenId), _useZro, _adapterParams);
}
function estimateSendBatchFee(
uint16 _dstChainId,
bytes memory _toAddress,
uint256[] memory _tokenIds,
bool _useZro,
bytes memory _adapterParams
) public view virtual override returns (uint256 nativeFee, uint256 zroFee) {
bytes memory payload = abi.encode(_toAddress, _tokenIds);
return lzEndpoint.estimateFees(_dstChainId, address(this), payload, _useZro, _adapterParams);
}
function sendFrom(
address _from,
uint16 _dstChainId,
bytes memory _toAddress,
uint256 _tokenId,
address payable _refundAddress,
address _zroPaymentAddress,
bytes memory _adapterParams
) public payable virtual override {
_send(
_from,
_dstChainId,
_toAddress,
_toSingletonArray(_tokenId),
_refundAddress,
_zroPaymentAddress,
_adapterParams
);
}
function sendBatchFrom(
address _from,
uint16 _dstChainId,
bytes memory _toAddress,
uint256[] memory _tokenIds,
address payable _refundAddress,
address _zroPaymentAddress,
bytes memory _adapterParams
) public payable virtual override {
_send(_from, _dstChainId, _toAddress, _tokenIds, _refundAddress, _zroPaymentAddress, _adapterParams);
}
function _send(
address _from,
uint16 _dstChainId,
bytes memory _toAddress,
uint256[] memory _tokenIds,
address payable _refundAddress,
address _zroPaymentAddress,
bytes memory _adapterParams
) internal virtual {
// allow 1 by default
require(_tokenIds.length > 0, "tokenIds[] is empty");
require(
_tokenIds.length == 1 || _tokenIds.length <= dstChainIdToBatchLimit[_dstChainId],
"batch size exceeds dst batch limit"
);
for (uint256 i = 0; i < _tokenIds.length; i++) {
_debitFrom(_from, _dstChainId, _toAddress, _tokenIds[i]);
}
bytes memory payload = abi.encode(_toAddress, _tokenIds);
_checkGasLimit(
_dstChainId,
FUNCTION_TYPE_SEND,
_adapterParams,
dstChainIdToTransferGas[_dstChainId] * _tokenIds.length
);
_lzSend(_dstChainId, payload, _refundAddress, _zroPaymentAddress, _adapterParams, msg.value);
emit SendToChain(_dstChainId, _from, _toAddress, _tokenIds);
}
function _nonblockingLzReceive(
uint16 _srcChainId,
bytes memory _srcAddress,
uint64, /*_nonce*/
bytes memory _payload
) internal virtual override {
// decode and load the toAddress
(bytes memory toAddressBytes, uint256[] memory tokenIds) = abi.decode(_payload, (bytes, uint256[]));
if (tokenIds[0] == 0) {
return;
}
address toAddress;
assembly {
toAddress := mload(add(toAddressBytes, 20))
}
uint256 nextIndex = _creditTill(_srcChainId, toAddress, 0, tokenIds);
if (nextIndex < tokenIds.length) {
// not enough gas to complete transfers, store to be cleared in another tx
bytes32 hashedPayload = keccak256(_payload);
storedCredits[hashedPayload] = StoredCredit(_srcChainId, toAddress, nextIndex, true);
emit CreditStored(hashedPayload, _payload);
}
emit ReceiveFromChain(_srcChainId, _srcAddress, toAddress, tokenIds);
}
// Public function for anyone to clear and deliver the remaining batch sent tokenIds
function clearCredits(bytes memory _payload) external virtual nonReentrant {
bytes32 hashedPayload = keccak256(_payload);
require(storedCredits[hashedPayload].creditsRemain, "no credits stored");
(, uint256[] memory tokenIds) = abi.decode(_payload, (bytes, uint256[]));
uint256 nextIndex = _creditTill(
storedCredits[hashedPayload].srcChainId,
storedCredits[hashedPayload].toAddress,
storedCredits[hashedPayload].index,
tokenIds
);
require(nextIndex > storedCredits[hashedPayload].index, "not enough gas to process credit transfer");
if (nextIndex == tokenIds.length) {
// cleared the credits, delete the element
delete storedCredits[hashedPayload];
emit CreditCleared(hashedPayload);
} else {
// store the next index to mint
storedCredits[hashedPayload] = StoredCredit(
storedCredits[hashedPayload].srcChainId,
storedCredits[hashedPayload].toAddress,
nextIndex,
true
);
}
}
// When a srcChain has the ability to transfer more chainIds in a single tx than the dst can do.
// Needs the ability to iterate and stop if the minGasToTransferAndStore is not met
function _creditTill(
uint16 _srcChainId,
address _toAddress,
uint256 _startIndex,
uint256[] memory _tokenIds
) internal returns (uint256) {
uint256 i = _startIndex;
while (i < _tokenIds.length) {
// if not enough gas to process, store this index for next loop
if (gasleft() < minGasToTransferAndStore) break;
_creditTo(_srcChainId, _toAddress, _tokenIds[i]);
i++;
}
// indicates the next index to send of tokenIds,
// if i == tokenIds.length, we are finished
return i;
}
function setMinGasToTransferAndStore(uint256 _minGasToTransferAndStore) external onlyOwner {
require(_minGasToTransferAndStore > 0, "minGasToTransferAndStore must be > 0");
minGasToTransferAndStore = _minGasToTransferAndStore;
emit SetMinGasToTransferAndStore(_minGasToTransferAndStore);
}
// ensures enough gas in adapter params to handle batch transfer gas amounts on the dst
function setDstChainIdToTransferGas(uint16 _dstChainId, uint256 _dstChainIdToTransferGas) external onlyOwner {
require(_dstChainIdToTransferGas > 0, "dstChainIdToTransferGas must be > 0");
dstChainIdToTransferGas[_dstChainId] = _dstChainIdToTransferGas;
emit SetDstChainIdToTransferGas(_dstChainId, _dstChainIdToTransferGas);
}
// limit on src the amount of tokens to batch send
function setDstChainIdToBatchLimit(uint16 _dstChainId, uint256 _dstChainIdToBatchLimit) external onlyOwner {
require(_dstChainIdToBatchLimit > 0, "dstChainIdToBatchLimit must be > 0");
dstChainIdToBatchLimit[_dstChainId] = _dstChainIdToBatchLimit;
emit SetDstChainIdToBatchLimit(_dstChainId, _dstChainIdToBatchLimit);
}
function _debitFrom(
address _from,
uint16 _dstChainId,
bytes memory _toAddress,
uint256 _tokenId
) internal virtual;
function _creditTo(
uint16 _srcChainId,
address _toAddress,
uint256 _tokenId
) internal virtual;
function _toSingletonArray(uint256 element) internal pure returns (uint256[] memory) {
uint256[] memory array = new uint256[](1);
array[0] = element;
return array;
}
}
// SPDX-License-Identifier: MIT
import "@openzeppelin/contracts/token/ERC721/IERC721.sol";
import "../interfaces/IONFT721Core.sol";
pragma solidity ^0.8.18;
interface IONFT721 is IONFT721Core, IERC721 {}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC721/ERC721.sol)
pragma solidity ^0.8.0;
import "./IERC721.sol";
import "./IERC721Receiver.sol";
import "./extensions/IERC721Metadata.sol";
import "../../utils/Address.sol";
import "../../utils/Context.sol";
import "../../utils/Strings.sol";
import "../../utils/introspection/ERC165.sol";
/**
* @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
* the Metadata extension, but not including the Enumerable extension, which is available separately as
* {ERC721Enumerable}.
*/
contract ERC721 is Context, ERC165, IERC721, IERC721Metadata {
using Address for address;
using Strings for uint256;
// Token name
string private _name;
// Token symbol
string private _symbol;
// Mapping from token ID to owner address
mapping(uint256 => address) private _owners;
// Mapping owner address to token count
mapping(address => uint256) private _balances;
// Mapping from token ID to approved address
mapping(uint256 => address) private _tokenApprovals;
// Mapping from owner to operator approvals
mapping(address => mapping(address => bool)) private _operatorApprovals;
/**
* @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
*/
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
}
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
return
interfaceId == type(IERC721).interfaceId ||
interfaceId == type(IERC721Metadata).interfaceId ||
super.supportsInterface(interfaceId);
}
/**
* @dev See {IERC721-balanceOf}.
*/
function balanceOf(address owner) public view virtual override returns (uint256) {
require(owner != address(0), "ERC721: address zero is not a valid owner");
return _balances[owner];
}
/**
* @dev See {IERC721-ownerOf}.
*/
function ownerOf(uint256 tokenId) public view virtual override returns (address) {
address owner = _owners[tokenId];
require(owner != address(0), "ERC721: invalid token ID");
return owner;
}
/**
* @dev See {IERC721Metadata-name}.
*/
function name() public view virtual override returns (string memory) {
return _name;
}
/**
* @dev See {IERC721Metadata-symbol}.
*/
function symbol() public view virtual override returns (string memory) {
return _symbol;
}
/**
* @dev See {IERC721Metadata-tokenURI}.
*/
function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
_requireMinted(tokenId);
string memory baseURI = _baseURI();
return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : "";
}
/**
* @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
* token will be the concatenation of the `baseURI` and the `tokenId`. Empty
* by default, can be overridden in child contracts.
*/
function _baseURI() internal view virtual returns (string memory) {
return "";
}
/**
* @dev See {IERC721-approve}.
*/
function approve(address to, uint256 tokenId) public virtual override {
address owner = ERC721.ownerOf(tokenId);
require(to != owner, "ERC721: approval to current owner");
require(
_msgSender() == owner || isApprovedForAll(owner, _msgSender()),
"ERC721: approve caller is not token owner nor approved for all"
);
_approve(to, tokenId);
}
/**
* @dev See {IERC721-getApproved}.
*/
function getApproved(uint256 tokenId) public view virtual override returns (address) {
_requireMinted(tokenId);
return _tokenApprovals[tokenId];
}
/**
* @dev See {IERC721-setApprovalForAll}.
*/
function setApprovalForAll(address operator, bool approved) public virtual override {
_setApprovalForAll(_msgSender(), operator, approved);
}
/**
* @dev See {IERC721-isApprovedForAll}.
*/
function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
return _operatorApprovals[owner][operator];
}
/**
* @dev See {IERC721-transferFrom}.
*/
function transferFrom(
address from,
address to,
uint256 tokenId
) public virtual override {
//solhint-disable-next-line max-line-length
require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner nor approved");
_transfer(from, to, tokenId);
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId
) public virtual override {
safeTransferFrom(from, to, tokenId, "");
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId,
bytes memory data
) public virtual override {
require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner nor approved");
_safeTransfer(from, to, tokenId, data);
}
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
* are aware of the ERC721 protocol to prevent tokens from being forever locked.
*
* `data` is additional data, it has no specified format and it is sent in call to `to`.
*
* This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
* implement alternative mechanisms to perform token transfer, such as signature-based.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function _safeTransfer(
address from,
address to,
uint256 tokenId,
bytes memory data
) internal virtual {
_transfer(from, to, tokenId);
require(_checkOnERC721Received(from, to, tokenId, data), "ERC721: transfer to non ERC721Receiver implementer");
}
/**
* @dev Returns whether `tokenId` exists.
*
* Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
*
* Tokens start existing when they are minted (`_mint`),
* and stop existing when they are burned (`_burn`).
*/
function _exists(uint256 tokenId) internal view virtual returns (bool) {
return _owners[tokenId] != address(0);
}
/**
* @dev Returns whether `spender` is allowed to manage `tokenId`.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {
address owner = ERC721.ownerOf(tokenId);
return (spender == owner || isApprovedForAll(owner, spender) || getApproved(tokenId) == spender);
}
/**
* @dev Safely mints `tokenId` and transfers it to `to`.
*
* Requirements:
*
* - `tokenId` must not exist.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function _safeMint(address to, uint256 tokenId) internal virtual {
_safeMint(to, tokenId, "");
}
/**
* @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
* forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
*/
function _safeMint(
address to,
uint256 tokenId,
bytes memory data
) internal virtual {
_mint(to, tokenId);
require(
_checkOnERC721Received(address(0), to, tokenId, data),
"ERC721: transfer to non ERC721Receiver implementer"
);
}
/**
* @dev Mints `tokenId` and transfers it to `to`.
*
* WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
*
* Requirements:
*
* - `tokenId` must not exist.
* - `to` cannot be the zero address.
*
* Emits a {Transfer} event.
*/
function _mint(address to, uint256 tokenId) internal virtual {
require(to != address(0), "ERC721: mint to the zero address");
require(!_exists(tokenId), "ERC721: token already minted");
_beforeTokenTransfer(address(0), to, tokenId);
_balances[to] += 1;
_owners[tokenId] = to;
emit Transfer(address(0), to, tokenId);
_afterTokenTransfer(address(0), to, tokenId);
}
/**
* @dev Destroys `tokenId`.
* The approval is cleared when the token is burned.
*
* Requirements:
*
* - `tokenId` must exist.
*
* Emits a {Transfer} event.
*/
function _burn(uint256 tokenId) internal virtual {
address owner = ERC721.ownerOf(tokenId);
_beforeTokenTransfer(owner, address(0), tokenId);
// Clear approvals
_approve(address(0), tokenId);
_balances[owner] -= 1;
delete _owners[tokenId];
emit Transfer(owner, address(0), tokenId);
_afterTokenTransfer(owner, address(0), tokenId);
}
/**
* @dev Transfers `tokenId` from `from` to `to`.
* As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
*
* Emits a {Transfer} event.
*/
function _transfer(
address from,
address to,
uint256 tokenId
) internal virtual {
require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer from incorrect owner");
require(to != address(0), "ERC721: transfer to the zero address");
_beforeTokenTransfer(from, to, tokenId);
// Clear approvals from the previous owner
_approve(address(0), tokenId);
_balances[from] -= 1;
_balances[to] += 1;
_owners[tokenId] = to;
emit Transfer(from, to, tokenId);
_afterTokenTransfer(from, to, tokenId);
}
/**
* @dev Approve `to` to operate on `tokenId`
*
* Emits an {Approval} event.
*/
function _approve(address to, uint256 tokenId) internal virtual {
_tokenApprovals[tokenId] = to;
emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
}
/**
* @dev Approve `operator` to operate on all of `owner` tokens
*
* Emits an {ApprovalForAll} event.
*/
function _setApprovalForAll(
address owner,
address operator,
bool approved
) internal virtual {
require(owner != operator, "ERC721: approve to caller");
_operatorApprovals[owner][operator] = approved;
emit ApprovalForAll(owner, operator, approved);
}
/**
* @dev Reverts if the `tokenId` has not been minted yet.
*/
function _requireMinted(uint256 tokenId) internal view virtual {
require(_exists(tokenId), "ERC721: invalid token ID");
}
/**
* @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
* The call is not executed if the target address is not a contract.
*
* @param from address representing the previous owner of the given token ID
* @param to target address that will receive the tokens
* @param tokenId uint256 ID of the token to be transferred
* @param data bytes optional data to send along with the call
* @return bool whether the call correctly returned the expected magic value
*/
function _checkOnERC721Received(
address from,
address to,
uint256 tokenId,
bytes memory data
) private returns (bool) {
if (to.isContract()) {
try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, data) returns (bytes4 retval) {
return retval == IERC721Receiver.onERC721Received.selector;
} catch (bytes memory reason) {
if (reason.length == 0) {
revert("ERC721: transfer to non ERC721Receiver implementer");
} else {
/// @solidity memory-safe-assembly
assembly {
revert(add(32, reason), mload(reason))
}
}
}
} else {
return true;
}
}
/**
* @dev Hook that is called before any token transfer. This includes minting
* and burning.
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
* transferred to `to`.
* - When `from` is zero, `tokenId` will be minted for `to`.
* - When `to` is zero, ``from``'s `tokenId` will be burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _beforeTokenTransfer(
address from,
address to,
uint256 tokenId
) internal virtual {}
/**
* @dev Hook that is called after any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _afterTokenTransfer(
address from,
address to,
uint256 tokenId
) internal virtual {}
}
// SPDX-License-Identifier: MIT
import "@openzeppelin/contracts/utils/introspection/ERC165.sol";
pragma solidity ^0.8.18;
interface IONFT721Core is IERC165 {
/**
* @dev Emitted when `_tokenIds[]` are moved from the `_sender` to (`_dstChainId`, `_toAddress`)
* `_nonce` is the outbound nonce from
*/
event SendToChain(uint16 indexed _dstChainId, address indexed _from, bytes indexed _toAddress, uint256[] _tokenIds);
event ReceiveFromChain(
uint16 indexed _srcChainId,
bytes indexed _srcAddress,
address indexed _toAddress,
uint256[] _tokenIds
);
event SetMinGasToTransferAndStore(uint256 _minGasToTransferAndStore);
event SetDstChainIdToTransferGas(uint16 _dstChainId, uint256 _dstChainIdToTransferGas);
event SetDstChainIdToBatchLimit(uint16 _dstChainId, uint256 _dstChainIdToBatchLimit);
/**
* @dev Emitted when `_payload` was received from lz, but not enough gas to deliver all tokenIds
*/
event CreditStored(bytes32 _hashedPayload, bytes _payload);
/**
* @dev Emitted when `_hashedPayload` has been completely delivered
*/
event CreditCleared(bytes32 _hashedPayload);
/**
* @dev send token `_tokenId` to (`_dstChainId`, `_toAddress`) from `_from`
* `_toAddress` can be any size depending on the `dstChainId`.
* `_zroPaymentAddress` set to address(0x0) if not paying in ZRO (LayerZero Token)
* `_adapterParams` is a flexible bytes array to indicate messaging adapter services
*/
function sendFrom(
address _from,
uint16 _dstChainId,
bytes calldata _toAddress,
uint256 _tokenId,
address payable _refundAddress,
address _zroPaymentAddress,
bytes calldata _adapterParams
) external payable;
/**
* @dev send tokens `_tokenIds[]` to (`_dstChainId`, `_toAddress`) from `_from`
* `_toAddress` can be any size depending on the `dstChainId`.
* `_zroPaymentAddress` set to address(0x0) if not paying in ZRO (LayerZero Token)
* `_adapterParams` is a flexible bytes array to indicate messaging adapter services
*/
function sendBatchFrom(
address _from,
uint16 _dstChainId,
bytes calldata _toAddress,
uint256[] calldata _tokenIds,
address payable _refundAddress,
address _zroPaymentAddress,
bytes calldata _adapterParams
) external payable;
/**
* @dev estimate send token `_tokenId` to (`_dstChainId`, `_toAddress`)
* _dstChainId - L0 defined chain id to send tokens too
* _toAddress - dynamic bytes array which contains the address to whom you are sending tokens to on the dstChain
* _tokenId - token Id to transfer
* _useZro - indicates to use zro to pay L0 fees
* _adapterParams - flexible bytes array to indicate messaging adapter services in L0
*/
function estimateSendFee(
uint16 _dstChainId,
bytes calldata _toAddress,
uint256 _tokenId,
bool _useZro,
bytes calldata _adapterParams
) external view returns (uint256 nativeFee, uint256 zroFee);
/**
* @dev estimate send token `_tokenId` to (`_dstChainId`, `_toAddress`)
* _dstChainId - L0 defined chain id to send tokens too
* _toAddress - dynamic bytes array which contains the address to whom you are sending tokens to on the dstChain
* _tokenIds[] - token Ids to transfer
* _useZro - indicates to use zro to pay L0 fees
* _adapterParams - flexible bytes array to indicate messaging adapter services in L0
*/
function estimateSendBatchFee(
uint16 _dstChainId,
bytes calldata _toAddress,
uint256[] calldata _tokenIds,
bool _useZro,
bytes calldata _adapterParams
) external view returns (uint256 nativeFee, uint256 zroFee);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
pragma solidity ^0.8.0;
import "./IERC165.sol";
/**
* @dev Implementation of the {IERC165} interface.
*
* Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
* for the additional interface id that will be supported. For example:
*
* ```solidity
* function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
* return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
* }
* ```
*
* Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
*/
abstract contract ERC165 is IERC165 {
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
return interfaceId == type(IERC165).interfaceId;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (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
pragma solidity ^0.8.0;
import "./LzApp.sol";
import "../libraries/ExcessivelySafeCall.sol";
/*
* the default LayerZero messaging behaviour is blocking, i.e. any failed message will block the channel
* this abstract class try-catch all fail messages and store locally for future retry. hence, non-blocking
* NOTE: if the srcAddress is not configured properly, it will still block the message pathway from (srcChainId, srcAddress)
*/
abstract contract NonblockingLzApp is LzApp {
using ExcessivelySafeCall for address;
constructor(address _endpoint) LzApp(_endpoint) {}
mapping(uint16 => mapping(bytes => mapping(uint64 => bytes32))) public failedMessages;
event MessageFailed(uint16 _srcChainId, bytes _srcAddress, uint64 _nonce, bytes _payload, bytes _reason);
event RetryMessageSuccess(uint16 _srcChainId, bytes _srcAddress, uint64 _nonce, bytes32 _payloadHash);
// overriding the virtual function in LzReceiver
function _blockingLzReceive(
uint16 _srcChainId,
bytes memory _srcAddress,
uint64 _nonce,
bytes memory _payload
) internal virtual override {
(bool success, bytes memory reason) = address(this).excessivelySafeCall(
gasleft(),
150,
abi.encodeWithSelector(this.nonblockingLzReceive.selector, _srcChainId, _srcAddress, _nonce, _payload)
);
if (!success) {
_storeFailedMessage(_srcChainId, _srcAddress, _nonce, _payload, reason);
}
}
function _storeFailedMessage(
uint16 _srcChainId,
bytes memory _srcAddress,
uint64 _nonce,
bytes memory _payload,
bytes memory _reason
) internal virtual {
failedMessages[_srcChainId][_srcAddress][_nonce] = keccak256(_payload);
emit MessageFailed(_srcChainId, _srcAddress, _nonce, _payload, _reason);
}
function nonblockingLzReceive(
uint16 _srcChainId,
bytes calldata _srcAddress,
uint64 _nonce,
bytes calldata _payload
) public virtual {
// only internal transaction
require(_msgSender() == address(this), "NonblockingLzApp: caller must be LzApp");
_nonblockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
}
//@notice override this function
function _nonblockingLzReceive(
uint16 _srcChainId,
bytes memory _srcAddress,
uint64 _nonce,
bytes memory _payload
) internal virtual;
function retryMessage(
uint16 _srcChainId,
bytes calldata _srcAddress,
uint64 _nonce,
bytes calldata _payload
) public payable virtual {
// assert there is message to retry
bytes32 payloadHash = failedMessages[_srcChainId][_srcAddress][_nonce];
require(payloadHash != bytes32(0), "NonblockingLzApp: no stored message");
require(keccak256(_payload) == payloadHash, "NonblockingLzApp: invalid payload");
// clear the stored message
failedMessages[_srcChainId][_srcAddress][_nonce] = bytes32(0);
// execute the message. revert if it fails again
_nonblockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
emit RetryMessageSuccess(_srcChainId, _srcAddress, _nonce, payloadHash);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC165 standard, as defined in the
* https://eips.ethereum.org/EIPS/eip-165[EIP].
*
* Implementers can declare support of contract interfaces, which can then be
* queried by others ({ERC165Checker}).
*
* For an implementation, see {ERC165}.
*/
interface IERC165 {
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
* to learn more about how these ids are created.
*
* This function call must use less than 30 000 gas.
*/
function supportsInterface(bytes4 interfaceId) external view returns (bool);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/access/Ownable.sol";
import "./interfaces/ILayerZeroReceiver.sol";
import "./interfaces/ILayerZeroUserApplicationConfig.sol";
import "./interfaces/ILayerZeroEndpoint.sol";
import "../libraries/BytesLib.sol";
/*
* a generic LzReceiver implementation
*/
abstract contract LzApp is Ownable, ILayerZeroReceiver, ILayerZeroUserApplicationConfig {
using BytesLib for bytes;
// ua can not send payload larger than this by default, but it can be changed by the ua owner
uint public constant DEFAULT_PAYLOAD_SIZE_LIMIT = 10000;
ILayerZeroEndpoint public immutable lzEndpoint;
mapping(uint16 => bytes) public trustedRemoteLookup;
mapping(uint16 => mapping(uint16 => uint)) public minDstGasLookup;
mapping(uint16 => uint) public payloadSizeLimitLookup;
address public precrime;
event SetPrecrime(address precrime);
event SetTrustedRemote(uint16 _remoteChainId, bytes _path);
event SetTrustedRemoteAddress(uint16 _remoteChainId, bytes _remoteAddress);
event SetMinDstGas(uint16 _dstChainId, uint16 _type, uint _minDstGas);
constructor(address _endpoint) {
lzEndpoint = ILayerZeroEndpoint(_endpoint);
}
function lzReceive(
uint16 _srcChainId,
bytes calldata _srcAddress,
uint64 _nonce,
bytes calldata _payload
) public virtual override {
// lzReceive must be called by the endpoint for security
require(_msgSender() == address(lzEndpoint), "LzApp: invalid endpoint caller");
bytes memory trustedRemote = trustedRemoteLookup[_srcChainId];
// if will still block the message pathway from (srcChainId, srcAddress). should not receive message from untrusted remote.
require(
_srcAddress.length == trustedRemote.length && trustedRemote.length > 0 && keccak256(_srcAddress) == keccak256(trustedRemote),
"LzApp: invalid source sending contract"
);
_blockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
}
// abstract function - the default behaviour of LayerZero is blocking. See: NonblockingLzApp if you dont need to enforce ordered messaging
function _blockingLzReceive(
uint16 _srcChainId,
bytes memory _srcAddress,
uint64 _nonce,
bytes memory _payload
) internal virtual;
function _lzSend(
uint16 _dstChainId,
bytes memory _payload,
address payable _refundAddress,
address _zroPaymentAddress,
bytes memory _adapterParams,
uint _nativeFee
) internal virtual {
bytes memory trustedRemote = trustedRemoteLookup[_dstChainId];
require(trustedRemote.length != 0, "LzApp: destination chain is not a trusted source");
_checkPayloadSize(_dstChainId, _payload.length);
lzEndpoint.send{value: _nativeFee}(_dstChainId, trustedRemote, _payload, _refundAddress, _zroPaymentAddress, _adapterParams);
}
function _checkGasLimit(
uint16 _dstChainId,
uint16 _type,
bytes memory _adapterParams,
uint _extraGas
) internal view virtual {
uint providedGasLimit = _getGasLimit(_adapterParams);
uint minGasLimit = minDstGasLookup[_dstChainId][_type];
require(minGasLimit > 0, "LzApp: minGasLimit not set");
require(providedGasLimit >= minGasLimit + _extraGas, "LzApp: gas limit is too low");
}
function _getGasLimit(bytes memory _adapterParams) internal pure virtual returns (uint gasLimit) {
require(_adapterParams.length >= 34, "LzApp: invalid adapterParams");
assembly {
gasLimit := mload(add(_adapterParams, 34))
}
}
function _checkPayloadSize(uint16 _dstChainId, uint _payloadSize) internal view virtual {
uint payloadSizeLimit = payloadSizeLimitLookup[_dstChainId];
if (payloadSizeLimit == 0) {
// use default if not set
payloadSizeLimit = DEFAULT_PAYLOAD_SIZE_LIMIT;
}
require(_payloadSize <= payloadSizeLimit, "LzApp: payload size is too large");
}
//---------------------------UserApplication config----------------------------------------
function getConfig(
uint16 _version,
uint16 _chainId,
address,
uint _configType
) external view returns (bytes memory) {
return lzEndpoint.getConfig(_version, _chainId, address(this), _configType);
}
// generic config for LayerZero user Application
function setConfig(
uint16 _version,
uint16 _chainId,
uint _configType,
bytes calldata _config
) external override onlyOwner {
lzEndpoint.setConfig(_version, _chainId, _configType, _config);
}
function setSendVersion(uint16 _version) external override onlyOwner {
lzEndpoint.setSendVersion(_version);
}
function setReceiveVersion(uint16 _version) external override onlyOwner {
lzEndpoint.setReceiveVersion(_version);
}
function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external override onlyOwner {
lzEndpoint.forceResumeReceive(_srcChainId, _srcAddress);
}
// _path = abi.encodePacked(remoteAddress, localAddress)
// this function set the trusted path for the cross-chain communication
function setTrustedRemote(uint16 _remoteChainId, bytes calldata _path) external onlyOwner {
trustedRemoteLookup[_remoteChainId] = _path;
emit SetTrustedRemote(_remoteChainId, _path);
}
function setTrustedRemoteAddress(uint16 _remoteChainId, bytes calldata _remoteAddress) external onlyOwner {
trustedRemoteLookup[_remoteChainId] = abi.encodePacked(_remoteAddress, address(this));
emit SetTrustedRemoteAddress(_remoteChainId, _remoteAddress);
}
function getTrustedRemoteAddress(uint16 _remoteChainId) external view returns (bytes memory) {
bytes memory path = trustedRemoteLookup[_remoteChainId];
require(path.length != 0, "LzApp: no trusted path record");
return path.slice(0, path.length - 20); // the last 20 bytes should be address(this)
}
function setPrecrime(address _precrime) external onlyOwner {
precrime = _precrime;
emit SetPrecrime(_precrime);
}
function setMinDstGas(
uint16 _dstChainId,
uint16 _packetType,
uint _minGas
) external onlyOwner {
minDstGasLookup[_dstChainId][_packetType] = _minGas;
emit SetMinDstGas(_dstChainId, _packetType, _minGas);
}
// if the size is 0, it means default size limit
function setPayloadSizeLimit(uint16 _dstChainId, uint _size) external onlyOwner {
payloadSizeLimitLookup[_dstChainId] = _size;
}
//--------------------------- VIEW FUNCTION ----------------------------------------
function isTrustedRemote(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool) {
bytes memory trustedSource = trustedRemoteLookup[_srcChainId];
return keccak256(trustedSource) == keccak256(_srcAddress);
}
}
// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity >=0.7.6;
library ExcessivelySafeCall {
uint constant LOW_28_MASK = 0x00000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffff;
/// @notice Use when you _really_ really _really_ don't trust the called
/// contract. This prevents the called contract from causing reversion of
/// the caller in as many ways as we can.
/// @dev The main difference between this and a solidity low-level call is
/// that we limit the number of bytes that the callee can cause to be
/// copied to caller memory. This prevents stupid things like malicious
/// contracts returning 10,000,000 bytes causing a local OOG when copying
/// to memory.
/// @param _target The address to call
/// @param _gas The amount of gas to forward to the remote contract
/// @param _maxCopy The maximum number of bytes of returndata to copy
/// to memory.
/// @param _calldata The data to send to the remote contract
/// @return success and returndata, as `.call()`. Returndata is capped to
/// `_maxCopy` bytes.
function excessivelySafeCall(
address _target,
uint _gas,
uint16 _maxCopy,
bytes memory _calldata
) internal returns (bool, bytes memory) {
// set up for assembly call
uint _toCopy;
bool _success;
bytes memory _returnData = new bytes(_maxCopy);
// dispatch message to recipient
// by assembly calling "handle" function
// we call via assembly to avoid memcopying a very large returndata
// returned by a malicious contract
assembly {
_success := call(
_gas, // gas
_target, // recipient
0, // ether value
add(_calldata, 0x20), // inloc
mload(_calldata), // inlen
0, // outloc
0 // outlen
)
// limit our copy to 256 bytes
_toCopy := returndatasize()
if gt(_toCopy, _maxCopy) {
_toCopy := _maxCopy
}
// Store the length of the copied bytes
mstore(_returnData, _toCopy)
// copy the bytes from returndata[0:_toCopy]
returndatacopy(add(_returnData, 0x20), 0, _toCopy)
}
return (_success, _returnData);
}
/// @notice Use when you _really_ really _really_ don't trust the called
/// contract. This prevents the called contract from causing reversion of
/// the caller in as many ways as we can.
/// @dev The main difference between this and a solidity low-level call is
/// that we limit the number of bytes that the callee can cause to be
/// copied to caller memory. This prevents stupid things like malicious
/// contracts returning 10,000,000 bytes causing a local OOG when copying
/// to memory.
/// @param _target The address to call
/// @param _gas The amount of gas to forward to the remote contract
/// @param _maxCopy The maximum number of bytes of returndata to copy
/// to memory.
/// @param _calldata The data to send to the remote contract
/// @return success and returndata, as `.call()`. Returndata is capped to
/// `_maxCopy` bytes.
function excessivelySafeStaticCall(
address _target,
uint _gas,
uint16 _maxCopy,
bytes memory _calldata
) internal view returns (bool, bytes memory) {
// set up for assembly call
uint _toCopy;
bool _success;
bytes memory _returnData = new bytes(_maxCopy);
// dispatch message to recipient
// by assembly calling "handle" function
// we call via assembly to avoid memcopying a very large returndata
// returned by a malicious contract
assembly {
_success := staticcall(
_gas, // gas
_target, // recipient
add(_calldata, 0x20), // inloc
mload(_calldata), // inlen
0, // outloc
0 // outlen
)
// limit our copy to 256 bytes
_toCopy := returndatasize()
if gt(_toCopy, _maxCopy) {
_toCopy := _maxCopy
}
// Store the length of the copied bytes
mstore(_returnData, _toCopy)
// copy the bytes from returndata[0:_toCopy]
returndatacopy(add(_returnData, 0x20), 0, _toCopy)
}
return (_success, _returnData);
}
/**
* @notice Swaps function selectors in encoded contract calls
* @dev Allows reuse of encoded calldata for functions with identical
* argument types but different names. It simply swaps out the first 4 bytes
* for the new selector. This function modifies memory in place, and should
* only be used with caution.
* @param _newSelector The new 4-byte selector
* @param _buf The encoded contract args
*/
function swapSelector(bytes4 _newSelector, bytes memory _buf) internal pure {
require(_buf.length >= 4);
uint _mask = LOW_28_MASK;
assembly {
// load the first word of
let _word := mload(add(_buf, 0x20))
// mask out the top 4 bytes
// /x
_word := and(_word, _mask)
_word := or(_newSelector, _word)
mstore(add(_buf, 0x20), _word)
}
}
}
// 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: Unlicense
/*
* @title Solidity Bytes Arrays Utils
* @author Gonçalo Sá <[email protected]>
*
* @dev Bytes tightly packed arrays utility library for ethereum contracts written in Solidity.
* The library lets you concatenate, slice and type cast bytes arrays both in memory and storage.
*/
pragma solidity >=0.8.0 <0.9.0;
library BytesLib {
function concat(bytes memory _preBytes, bytes memory _postBytes) internal pure returns (bytes memory) {
bytes memory tempBytes;
assembly {
// Get a location of some free memory and store it in tempBytes as
// Solidity does for memory variables.
tempBytes := mload(0x40)
// Store the length of the first bytes array at the beginning of
// the memory for tempBytes.
let length := mload(_preBytes)
mstore(tempBytes, length)
// Maintain a memory counter for the current write location in the
// temp bytes array by adding the 32 bytes for the array length to
// the starting location.
let mc := add(tempBytes, 0x20)
// Stop copying when the memory counter reaches the length of the
// first bytes array.
let end := add(mc, length)
for {
// Initialize a copy counter to the start of the _preBytes data,
// 32 bytes into its memory.
let cc := add(_preBytes, 0x20)
} lt(mc, end) {
// Increase both counters by 32 bytes each iteration.
mc := add(mc, 0x20)
cc := add(cc, 0x20)
} {
// Write the _preBytes data into the tempBytes memory 32 bytes
// at a time.
mstore(mc, mload(cc))
}
// Add the length of _postBytes to the current length of tempBytes
// and store it as the new length in the first 32 bytes of the
// tempBytes memory.
length := mload(_postBytes)
mstore(tempBytes, add(length, mload(tempBytes)))
// Move the memory counter back from a multiple of 0x20 to the
// actual end of the _preBytes data.
mc := end
// Stop copying when the memory counter reaches the new combined
// length of the arrays.
end := add(mc, length)
for {
let cc := add(_postBytes, 0x20)
} lt(mc, end) {
mc := add(mc, 0x20)
cc := add(cc, 0x20)
} {
mstore(mc, mload(cc))
}
// Update the free-memory pointer by padding our last write location
// to 32 bytes: add 31 bytes to the end of tempBytes to move to the
// next 32 byte block, then round down to the nearest multiple of
// 32. If the sum of the length of the two arrays is zero then add
// one before rounding down to leave a blank 32 bytes (the length block with 0).
mstore(
0x40,
and(
add(add(end, iszero(add(length, mload(_preBytes)))), 31),
not(31) // Round down to the nearest 32 bytes.
)
)
}
return tempBytes;
}
function concatStorage(bytes storage _preBytes, bytes memory _postBytes) internal {
assembly {
// Read the first 32 bytes of _preBytes storage, which is the length
// of the array. (We don't need to use the offset into the slot
// because arrays use the entire slot.)
let fslot := sload(_preBytes.slot)
// Arrays of 31 bytes or less have an even value in their slot,
// while longer arrays have an odd value. The actual length is
// the slot divided by two for odd values, and the lowest order
// byte divided by two for even values.
// If the slot is even, bitwise and the slot with 255 and divide by
// two to get the length. If the slot is odd, bitwise and the slot
// with -1 and divide by two.
let slength := div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
let mlength := mload(_postBytes)
let newlength := add(slength, mlength)
// slength can contain both the length and contents of the array
// if length < 32 bytes so let's prepare for that
// v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storage
switch add(lt(slength, 32), lt(newlength, 32))
case 2 {
// Since the new array still fits in the slot, we just need to
// update the contents of the slot.
// uint256(bytes_storage) = uint256(bytes_storage) + uint256(bytes_memory) + new_length
sstore(
_preBytes.slot,
// all the modifications to the slot are inside this
// next block
add(
// we can just add to the slot contents because the
// bytes we want to change are the LSBs
fslot,
add(
mul(
div(
// load the bytes from memory
mload(add(_postBytes, 0x20)),
// zero all bytes to the right
exp(0x100, sub(32, mlength))
),
// and now shift left the number of bytes to
// leave space for the length in the slot
exp(0x100, sub(32, newlength))
),
// increase length by the double of the memory
// bytes length
mul(mlength, 2)
)
)
)
}
case 1 {
// The stored value fits in the slot, but the combined value
// will exceed it.
// get the keccak hash to get the contents of the array
mstore(0x0, _preBytes.slot)
let sc := add(keccak256(0x0, 0x20), div(slength, 32))
// save new length
sstore(_preBytes.slot, add(mul(newlength, 2), 1))
// The contents of the _postBytes array start 32 bytes into
// the structure. Our first read should obtain the `submod`
// bytes that can fit into the unused space in the last word
// of the stored array. To get this, we read 32 bytes starting
// from `submod`, so the data we read overlaps with the array
// contents by `submod` bytes. Masking the lowest-order
// `submod` bytes allows us to add that value directly to the
// stored value.
let submod := sub(32, slength)
let mc := add(_postBytes, submod)
let end := add(_postBytes, mlength)
let mask := sub(exp(0x100, submod), 1)
sstore(sc, add(and(fslot, 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff00), and(mload(mc), mask)))
for {
mc := add(mc, 0x20)
sc := add(sc, 1)
} lt(mc, end) {
sc := add(sc, 1)
mc := add(mc, 0x20)
} {
sstore(sc, mload(mc))
}
mask := exp(0x100, sub(mc, end))
sstore(sc, mul(div(mload(mc), mask), mask))
}
default {
// get the keccak hash to get the contents of the array
mstore(0x0, _preBytes.slot)
// Start copying to the last used word of the stored array.
let sc := add(keccak256(0x0, 0x20), div(slength, 32))
// save new length
sstore(_preBytes.slot, add(mul(newlength, 2), 1))
// Copy over the first `submod` bytes of the new data as in
// case 1 above.
let slengthmod := mod(slength, 32)
let mlengthmod := mod(mlength, 32)
let submod := sub(32, slengthmod)
let mc := add(_postBytes, submod)
let end := add(_postBytes, mlength)
let mask := sub(exp(0x100, submod), 1)
sstore(sc, add(sload(sc), and(mload(mc), mask)))
for {
sc := add(sc, 1)
mc := add(mc, 0x20)
} lt(mc, end) {
sc := add(sc, 1)
mc := add(mc, 0x20)
} {
sstore(sc, mload(mc))
}
mask := exp(0x100, sub(mc, end))
sstore(sc, mul(div(mload(mc), mask), mask))
}
}
}
function slice(
bytes memory _bytes,
uint _start,
uint _length
) internal pure returns (bytes memory) {
require(_length + 31 >= _length, "slice_overflow");
require(_bytes.length >= _start + _length, "slice_outOfBounds");
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, uint _start) internal pure returns (address) {
require(_bytes.length >= _start + 20, "toAddress_outOfBounds");
address tempAddress;
assembly {
tempAddress := div(mload(add(add(_bytes, 0x20), _start)), 0x1000000000000000000000000)
}
return tempAddress;
}
function toUint8(bytes memory _bytes, uint _start) internal pure returns (uint8) {
require(_bytes.length >= _start + 1, "toUint8_outOfBounds");
uint8 tempUint;
assembly {
tempUint := mload(add(add(_bytes, 0x1), _start))
}
return tempUint;
}
function toUint16(bytes memory _bytes, uint _start) internal pure returns (uint16) {
require(_bytes.length >= _start + 2, "toUint16_outOfBounds");
uint16 tempUint;
assembly {
tempUint := mload(add(add(_bytes, 0x2), _start))
}
return tempUint;
}
function toUint32(bytes memory _bytes, uint _start) internal pure returns (uint32) {
require(_bytes.length >= _start + 4, "toUint32_outOfBounds");
uint32 tempUint;
assembly {
tempUint := mload(add(add(_bytes, 0x4), _start))
}
return tempUint;
}
function toUint64(bytes memory _bytes, uint _start) internal pure returns (uint64) {
require(_bytes.length >= _start + 8, "toUint64_outOfBounds");
uint64 tempUint;
assembly {
tempUint := mload(add(add(_bytes, 0x8), _start))
}
return tempUint;
}
function toUint96(bytes memory _bytes, uint _start) internal pure returns (uint96) {
require(_bytes.length >= _start + 12, "toUint96_outOfBounds");
uint96 tempUint;
assembly {
tempUint := mload(add(add(_bytes, 0xc), _start))
}
return tempUint;
}
function toUint128(bytes memory _bytes, uint _start) internal pure returns (uint128) {
require(_bytes.length >= _start + 16, "toUint128_outOfBounds");
uint128 tempUint;
assembly {
tempUint := mload(add(add(_bytes, 0x10), _start))
}
return tempUint;
}
function toUint256(bytes memory _bytes, uint _start) internal pure returns (uint) {
require(_bytes.length >= _start + 32, "toUint256_outOfBounds");
uint tempUint;
assembly {
tempUint := mload(add(add(_bytes, 0x20), _start))
}
return tempUint;
}
function toBytes32(bytes memory _bytes, uint _start) internal pure returns (bytes32) {
require(_bytes.length >= _start + 32, "toBytes32_outOfBounds");
bytes32 tempBytes32;
assembly {
tempBytes32 := mload(add(add(_bytes, 0x20), _start))
}
return tempBytes32;
}
function equal(bytes memory _preBytes, bytes memory _postBytes) internal pure returns (bool) {
bool success = true;
assembly {
let length := mload(_preBytes)
// if lengths don't match the arrays are not equal
switch eq(length, mload(_postBytes))
case 1 {
// cb is a circuit breaker in the for loop since there's
// no said feature for inline assembly loops
// cb = 1 - don't breaker
// cb = 0 - break
let cb := 1
let mc := add(_preBytes, 0x20)
let end := add(mc, length)
for {
let cc := add(_postBytes, 0x20)
// the next line is the loop condition:
// while(uint256(mc < end) + cb == 2)
} eq(add(lt(mc, end), cb), 2) {
mc := add(mc, 0x20)
cc := add(cc, 0x20)
} {
// if any of these checks fails then arrays are not equal
if iszero(eq(mload(mc), mload(cc))) {
// unsuccess:
success := 0
cb := 0
}
}
}
default {
// unsuccess:
success := 0
}
}
return success;
}
function equalStorage(bytes storage _preBytes, bytes memory _postBytes) internal view returns (bool) {
bool success = true;
assembly {
// we know _preBytes_offset is 0
let fslot := sload(_preBytes.slot)
// Decode the length of the stored array like in concatStorage().
let slength := div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
let mlength := mload(_postBytes)
// if lengths don't match the arrays are not equal
switch eq(slength, mlength)
case 1 {
// slength can contain both the length and contents of the array
// if length < 32 bytes so let's prepare for that
// v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storage
if iszero(iszero(slength)) {
switch lt(slength, 32)
case 1 {
// blank the last byte which is the length
fslot := mul(div(fslot, 0x100), 0x100)
if iszero(eq(fslot, mload(add(_postBytes, 0x20)))) {
// unsuccess:
success := 0
}
}
default {
// cb is a circuit breaker in the for loop since there's
// no said feature for inline assembly loops
// cb = 1 - don't breaker
// cb = 0 - break
let cb := 1
// get the keccak hash to get the contents of the array
mstore(0x0, _preBytes.slot)
let sc := keccak256(0x0, 0x20)
let mc := add(_postBytes, 0x20)
let end := add(mc, mlength)
// the next line is the loop condition:
// while(uint256(mc < end) + cb == 2)
for {
} eq(add(lt(mc, end), cb), 2) {
sc := add(sc, 1)
mc := add(mc, 0x20)
} {
if iszero(eq(sload(sc), mload(mc))) {
// unsuccess:
success := 0
cb := 0
}
}
}
}
}
default {
// unsuccess:
success := 0
}
}
return success;
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.5.0;
import "./ILayerZeroUserApplicationConfig.sol";
interface ILayerZeroEndpoint is ILayerZeroUserApplicationConfig {
// @notice send a LayerZero message to the specified address at a LayerZero endpoint.
// @param _dstChainId - the destination chain identifier
// @param _destination - the address on destination chain (in bytes). address length/format may vary by chains
// @param _payload - a custom bytes payload to send to the destination contract
// @param _refundAddress - if the source transaction is cheaper than the amount of value passed, refund the additional amount to this address
// @param _zroPaymentAddress - the address of the ZRO token holder who would pay for the transaction
// @param _adapterParams - parameters for custom functionality. e.g. receive airdropped native gas from the relayer on destination
function send(
uint16 _dstChainId,
bytes calldata _destination,
bytes calldata _payload,
address payable _refundAddress,
address _zroPaymentAddress,
bytes calldata _adapterParams
) external payable;
// @notice used by the messaging library to publish verified payload
// @param _srcChainId - the source chain identifier
// @param _srcAddress - the source contract (as bytes) at the source chain
// @param _dstAddress - the address on destination chain
// @param _nonce - the unbound message ordering nonce
// @param _gasLimit - the gas limit for external contract execution
// @param _payload - verified payload to send to the destination contract
function receivePayload(
uint16 _srcChainId,
bytes calldata _srcAddress,
address _dstAddress,
uint64 _nonce,
uint _gasLimit,
bytes calldata _payload
) external;
// @notice get the inboundNonce of a lzApp from a source chain which could be EVM or non-EVM chain
// @param _srcChainId - the source chain identifier
// @param _srcAddress - the source chain contract address
function getInboundNonce(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (uint64);
// @notice get the outboundNonce from this source chain which, consequently, is always an EVM
// @param _srcAddress - the source chain contract address
function getOutboundNonce(uint16 _dstChainId, address _srcAddress) external view returns (uint64);
// @notice gets a quote in source native gas, for the amount that send() requires to pay for message delivery
// @param _dstChainId - the destination chain identifier
// @param _userApplication - the user app address on this EVM chain
// @param _payload - the custom message to send over LayerZero
// @param _payInZRO - if false, user app pays the protocol fee in native token
// @param _adapterParam - parameters for the adapter service, e.g. send some dust native token to dstChain
function estimateFees(
uint16 _dstChainId,
address _userApplication,
bytes calldata _payload,
bool _payInZRO,
bytes calldata _adapterParam
) external view returns (uint nativeFee, uint zroFee);
// @notice get this Endpoint's immutable source identifier
function getChainId() external view returns (uint16);
// @notice the interface to retry failed message on this Endpoint destination
// @param _srcChainId - the source chain identifier
// @param _srcAddress - the source chain contract address
// @param _payload - the payload to be retried
function retryPayload(
uint16 _srcChainId,
bytes calldata _srcAddress,
bytes calldata _payload
) external;
// @notice query if any STORED payload (message blocking) at the endpoint.
// @param _srcChainId - the source chain identifier
// @param _srcAddress - the source chain contract address
function hasStoredPayload(uint16 _srcChainId, bytes calldata _srcAddress) external view returns (bool);
// @notice query if the _libraryAddress is valid for sending msgs.
// @param _userApplication - the user app address on this EVM chain
function getSendLibraryAddress(address _userApplication) external view returns (address);
// @notice query if the _libraryAddress is valid for receiving msgs.
// @param _userApplication - the user app address on this EVM chain
function getReceiveLibraryAddress(address _userApplication) external view returns (address);
// @notice query if the non-reentrancy guard for send() is on
// @return true if the guard is on. false otherwise
function isSendingPayload() external view returns (bool);
// @notice query if the non-reentrancy guard for receive() is on
// @return true if the guard is on. false otherwise
function isReceivingPayload() external view returns (bool);
// @notice get the configuration of the LayerZero messaging library of the specified version
// @param _version - messaging library version
// @param _chainId - the chainId for the pending config change
// @param _userApplication - the contract address of the user application
// @param _configType - type of configuration. every messaging library has its own convention.
function getConfig(
uint16 _version,
uint16 _chainId,
address _userApplication,
uint _configType
) external view returns (bytes memory);
// @notice get the send() LayerZero messaging library version
// @param _userApplication - the contract address of the user application
function getSendVersion(address _userApplication) external view returns (uint16);
// @notice get the lzReceive() LayerZero messaging library version
// @param _userApplication - the contract address of the user application
function getReceiveVersion(address _userApplication) external view returns (uint16);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.5.0;
interface ILayerZeroReceiver {
// @notice LayerZero endpoint will invoke this function to deliver the message on the destination
// @param _srcChainId - the source endpoint identifier
// @param _srcAddress - the source sending contract address from the source chain
// @param _nonce - the ordered message nonce
// @param _payload - the signed payload is the UA bytes has encoded to be sent
function lzReceive(
uint16 _srcChainId,
bytes calldata _srcAddress,
uint64 _nonce,
bytes calldata _payload
) external;
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.5.0;
interface ILayerZeroUserApplicationConfig {
// @notice set the configuration of the LayerZero messaging library of the specified version
// @param _version - messaging library version
// @param _chainId - the chainId for the pending config change
// @param _configType - type of configuration. every messaging library has its own convention.
// @param _config - configuration in the bytes. can encode arbitrary content.
function setConfig(
uint16 _version,
uint16 _chainId,
uint _configType,
bytes calldata _config
) external;
// @notice set the send() LayerZero messaging library version to _version
// @param _version - new messaging library version
function setSendVersion(uint16 _version) external;
// @notice set the lzReceive() LayerZero messaging library version to _version
// @param _version - new messaging library version
function setReceiveVersion(uint16 _version) external;
// @notice Only when the UA needs to resume the message flow in blocking mode and clear the stored payload
// @param _srcChainId - the chainId of the source chain
// @param _srcAddress - the contract address of the source contract at the source chain
function forceResumeReceive(uint16 _srcChainId, bytes calldata _srcAddress) external;
}
// 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 v4.7.0) (token/ERC721/IERC721.sol)
pragma solidity ^0.8.0;
import "../../utils/introspection/IERC165.sol";
/**
* @dev Required interface of an ERC721 compliant contract.
*/
interface IERC721 is IERC165 {
/**
* @dev Emitted when `tokenId` token is transferred from `from` to `to`.
*/
event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
*/
event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
*/
event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
/**
* @dev Returns the number of tokens in ``owner``'s account.
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @dev Returns the owner of the `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function ownerOf(uint256 tokenId) external view returns (address owner);
/**
* @dev Safely transfers `tokenId` token from `from` to `to`.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId,
bytes calldata data
) external;
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
* are aware of the ERC721 protocol to prevent tokens from being forever locked.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must have been allowed to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId
) external;
/**
* @dev Transfers `tokenId` token from `from` to `to`.
*
* WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
*
* Emits a {Transfer} event.
*/
function transferFrom(
address from,
address to,
uint256 tokenId
) external;
/**
* @dev Gives permission to `to` to transfer `tokenId` token to another account.
* The approval is cleared when the token is transferred.
*
* Only a single account can be approved at a time, so approving the zero address clears previous approvals.
*
* Requirements:
*
* - The caller must own the token or be an approved operator.
* - `tokenId` must exist.
*
* Emits an {Approval} event.
*/
function approve(address to, uint256 tokenId) external;
/**
* @dev Approve or remove `operator` as an operator for the caller.
* Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
*
* Requirements:
*
* - The `operator` cannot be the caller.
*
* Emits an {ApprovalForAll} event.
*/
function setApprovalForAll(address operator, bool _approved) external;
/**
* @dev Returns the account approved for `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function getApproved(uint256 tokenId) external view returns (address operator);
/**
* @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
*
* See {setApprovalForAll}
*/
function isApprovedForAll(address owner, address operator) external view returns (bool);
}
// 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 (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)
pragma solidity ^0.8.0;
/**
* @title ERC721 token receiver interface
* @dev Interface for any contract that wants to support safeTransfers
* from ERC721 asset contracts.
*/
interface IERC721Receiver {
/**
* @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
* by `operator` from `from`, this function is called.
*
* It must return its Solidity selector to confirm the token transfer.
* If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
*
* The selector can be obtained in Solidity with `IERC721Receiver.onERC721Received.selector`.
*/
function onERC721Received(
address operator,
address from,
uint256 tokenId,
bytes calldata data
) external returns (bytes4);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Strings.sol)
pragma solidity ^0.8.0;
/**
* @dev String operations.
*/
library Strings {
bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
uint8 private constant _ADDRESS_LENGTH = 20;
/**
* @dev Converts a `uint256` to its ASCII `string` decimal representation.
*/
function toString(uint256 value) internal pure returns (string memory) {
// Inspired by OraclizeAPI's implementation - MIT licence
// https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
if (value == 0) {
return "0";
}
uint256 temp = value;
uint256 digits;
while (temp != 0) {
digits++;
temp /= 10;
}
bytes memory buffer = new bytes(digits);
while (value != 0) {
digits -= 1;
buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
value /= 10;
}
return string(buffer);
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
*/
function toHexString(uint256 value) internal pure returns (string memory) {
if (value == 0) {
return "0x00";
}
uint256 temp = value;
uint256 length = 0;
while (temp != 0) {
length++;
temp >>= 8;
}
return toHexString(value, length);
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
*/
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] = _HEX_SYMBOLS[value & 0xf];
value >>= 4;
}
require(value == 0, "Strings: hex length insufficient");
return string(buffer);
}
/**
* @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
*/
function toHexString(address addr) internal pure returns (string memory) {
return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)
pragma solidity ^0.8.0;
import "../IERC721.sol";
/**
* @title ERC-721 Non-Fungible Token Standard, optional metadata extension
* @dev See https://eips.ethereum.org/EIPS/eip-721
*/
interface IERC721Metadata is IERC721 {
/**
* @dev Returns the token collection name.
*/
function name() external view returns (string memory);
/**
* @dev Returns the token collection symbol.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
*/
function tokenURI(uint256 tokenId) external view returns (string memory);
}