Contract Source Code:
// SPDX-License-Identifier: MIT
// Creator: https://github.com/cowlony-org
pragma solidity ^0.8.4;
import "@openzeppelin/contracts/access/AccessControlEnumerable.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "erc721a/contracts/extensions/ERC721ABurnable.sol";
import "./AllowlistSale.sol";
import "./ProxyRegistry.sol";
/**
* @title Cowlony contract
* @dev Extends ERC721A
*/
contract Cowlony is ERC721ABurnable, AllowlistSale, Ownable, AccessControlEnumerable, ReentrancyGuard {
using ECDSA for bytes32;
/**
@notice Role of administrative users allowed to expel a Cows from grazing.
@dev See expelFromGrazing().
*/
bytes32 public constant EXPULSION_ROLE = keccak256("EXPULSION_ROLE");
/**
@notice collection and contract meta data
*/
uint256 public COLLECTION_SIZE = 4998;
string public PROVENANCE_HASH;
string public baseURI;
string private _contractURI;
uint256 private defaultPublicSaleId;
constructor(
string memory name,
string memory symbol,
string memory provenance,
string memory initBaseURI,
string memory initContractURI,
uint256 _defaultPublicSaleId,
address payable _beneficiary
) ERC721A(name, symbol) {
PROVENANCE_HASH = provenance;
baseURI = initBaseURI;
_contractURI = initContractURI;
defaultPublicSaleId = _defaultPublicSaleId;
beneficiary = _beneficiary;
_grantRole(DEFAULT_ADMIN_ROLE, msg.sender);
// allowlist sale
_addSale(1, SaleConfig(1655913600, 1655917200, 20000000000000000, 5, 0xe12e7B6DDA6bC392b8441240459f7960E016D7Cb, false, false, true));
// public sale
_addSale(2, SaleConfig(1655917200, 1656090000, 40000000000000000, 5, address(0), true, false, true));
// freelist
_addSale(3, SaleConfig(1656090000, 1656104400, 0, 1, 0x842404201Be7CC0bc01f2afe9aF49dFe1A70Bf64, false, true, true));
// test sale only for one test mint after contract deploy
_addSale(42, SaleConfig(1655895600, 1655906400, 20000000000000000, 5, 0x83C6A23e0bBB11C17cC25dA0F5e3B36D64470deb, false, false, true));
}
// setup sales
/**
@dev creates allowlist config with the given id
*/
function addSale(
uint256 id,
uint256 startDate,
uint256 endDate,
uint256 price,
uint256 quantityLimit,
address signer,
bool checkUsedKeys) external onlyOwner {
_addSale(id, SaleConfig({
startDate: startDate,
endDate: endDate,
price: price,
quantityLimit: quantityLimit,
signer: signer,
isPublicSale: false,
checkUsedKeys: checkUsedKeys,
exists: true
}));
}
/**
@dev creates publicSale config with the given id
*/
function addPublicSale(
uint256 id,
uint256 startDate,
uint256 endDate,
uint256 price,
uint256 quantityLimit) external onlyOwner {
_addSale(id, SaleConfig({
startDate: startDate,
endDate: endDate,
price: price,
quantityLimit: quantityLimit,
signer: address(0),
isPublicSale: true,
checkUsedKeys: false,
exists: true
}));
}
/**
@dev removes the given sale id
*/
function removeSale(uint256 id) external onlyOwner {
_removeSale(id);
}
// mint functions
/**
@notice mints with verifying the provided key and saleId
* you can get your saleKey and saleId on cowlony.io
* this function handles both the free and allowlist mints
*/
function allowlistMint(uint256 quantity, bytes calldata saleKey, uint256 saleId) external payable nonReentrant {
require(totalSupply() + quantity <= COLLECTION_SIZE, "purchase would exceed max supply of Cows");
verify(quantity, saleKey, saleId);
_safeMint(msg.sender, quantity);
}
/**
@notice mints on public sale without verifying any key
*/
function publicMint(uint256 quantity) external payable nonReentrant {
require(totalSupply() + quantity <= COLLECTION_SIZE, "purchase would exceed max supply of Cows");
verifyPublicSale(quantity, defaultPublicSaleId);
_safeMint(msg.sender, quantity);
}
/**
@dev owner mint to fill up our treasury
*/
function ownerMint(uint256 quantity, address recipient) external onlyOwner nonReentrant {
require(totalSupply() + quantity <= COLLECTION_SIZE, "purchase would exceed max supply of Cows");
_safeMint(recipient, quantity);
}
// metadata
function setProvenance(string calldata provenance) external onlyOwner {
PROVENANCE_HASH = provenance;
}
function setBaseURI(string calldata newBaseURI) external onlyOwner {
baseURI = newBaseURI;
}
function _baseURI() internal view override returns (string memory) {
return baseURI;
}
function setContractURI(string calldata uri) external onlyOwner {
_contractURI = uri;
}
function contractURI() public view returns (string memory) {
return _contractURI;
}
function setDefaultPublicSaleId(uint256 saleId) external onlyOwner {
defaultPublicSaleId = saleId;
}
function getDefaultPublicSaleId() public view returns (uint256) {
return defaultPublicSaleId;
}
// OpenSeaFreeListing
/**
@dev configurations, feature switch and address
*/
bool public openSeaProxyOn = true;
address public openSeaProxy = 0xa5409ec958C83C3f309868babACA7c86DCB077c1;
/**
@notice When openSeaProxyOn no need to manually whitelist the OpenSea proxy to be able to list an item,
* it is whitelisted by us.
*/
function isApprovedForAll(address _owner, address operator) public view override returns (bool) {
if (openSeaProxyOn) {
ProxyRegistry openSeaProxyRegistry = ProxyRegistry(openSeaProxy);
if (address(openSeaProxyRegistry.proxies(_owner)) == operator) return true;
}
return super.isApprovedForAll(_owner, operator);
}
/**
@dev set the status of openSeaProxyOn
*/
function setOpenSeaProxyStatus(bool status) external onlyOwner {
openSeaProxyOn = status;
}
/**
@dev set OpenSea's proxy address, probably will be never used
*/
function setOpenSeaProxyAddress(address _address) external onlyOwner {
openSeaProxy = _address;
}
// grazing based on the Moonbirds nesting
// https://etherscan.io/token/0x23581767a106ae21c074b2276D25e5C3e136a68b
/**
@dev tokenId to active grazing start time (0 = not grazing).
*/
mapping(uint256 => uint256) private grazingStarted;
/**
@dev Cumulative per-token all time grazing, excluding the current period.
*/
mapping(uint256 => uint256) private grazingTotal;
/**
@dev Longest continuous grazing streak, excluding the current period.
*/
mapping(uint256 => uint256) private grazingMax;
/**
@notice Returns the length of time, in seconds, that the Cow has been grazing.
@dev Grazing is tied to a specific Cow, not to the owner, so it doesn't reset after a sale.
@return grazing Whether the Cow is currently grazing. MAY be true with zero current nesting if
* in the same block as grazing began.
@return current Zero if not currently grazing, otherwise the length of time since the most recent
* grazing began.
@return total Total period of time for which the Cow has been grazing across its life, including
* the current period.
@return max Longest continuous period of time for which the Cow has been grazing across its life,
* including the current period.
*/
function grazingPeriod(uint256 tokenId)
external
view
returns (
bool grazing,
uint256 current,
uint256 total,
uint256 max
) {
uint256 start = grazingStarted[tokenId];
if (start != 0) {
grazing = true;
current = block.timestamp - start;
}
total = current + grazingTotal[tokenId];
max = grazingMax[tokenId];
max = max > current ? max : current;
}
/**
@dev MUST only be modified by safeTransferWhileGrazing() if set to 1 then
* the _beforeTokenTransfer() block while grazing is disabled.
*/
uint256 private grazingTransfer = 1;
/**
@notice Transfer a token between addresses while the Cow is grazing, thus not resetting the grazing period.
*/
function safeTransferWhileGrazing(
address from,
address to,
uint256 tokenId
) external {
require(ownerOf(tokenId) == _msgSender(), "cowlony: Only owner");
grazingTransfer = 2;
safeTransferFrom(from, to, tokenId);
grazingTransfer = 1;
}
/**
@dev Blocks normal transfers while grazing.
*/
function _beforeTokenTransfers(
address,
address,
uint256 startTokenId,
uint256 quantity
) internal view override {
uint256 tokenId = startTokenId;
for (uint256 end = tokenId + quantity; tokenId < end; ++tokenId) {
require(
grazingStarted[tokenId] == 0 || grazingTransfer == 2,
"cowlony: grazing"
);
}
}
/**
@dev Emitted when a Cow begins grazing.
*/
event GrazingStarted(uint256 indexed tokenId);
/**
@dev Emitted when a Cow stops grazing, either through standard means or by expulsion.
*/
event GrazingStopped(uint256 indexed tokenId);
/**
@dev Emitted when a Cow is expelled from grazing.
*/
event Expelled(uint256 indexed tokenId);
/**
@notice Whether grazing is currently allowed.
@dev If false then grazing is blocked, but stopGrazing is always allowed.
*/
bool public grazingOpen = false;
/**
@notice Toggles the `grazingOpen` flag.
*/
function setGrazingOpen(bool open) external onlyOwner {
grazingOpen = open;
}
/**
@dev checks the Cow's owner
*/
modifier onlyApprovedOrOwner(uint256 tokenId) {
require(
_ownershipOf(tokenId).addr == _msgSender() ||
getApproved(tokenId) == _msgSender(),
"Not approved nor owner"
);
_;
}
/**
@notice Changes the Cow's grazing status.
*/
function toggleGrazing(uint256 tokenId)
internal
onlyApprovedOrOwner(tokenId)
{
uint256 start = grazingStarted[tokenId];
if (start == 0) {
require(grazingOpen, "cowlony: grazing unavailable");
grazingStarted[tokenId] = block.timestamp;
emit GrazingStarted(tokenId);
} else {
uint256 grazingTime = block.timestamp - start;
grazingTotal[tokenId] += grazingTime;
grazingStarted[tokenId] = 0;
if (grazingMax[tokenId] < grazingTime) {
grazingMax[tokenId] = grazingTime;
}
emit GrazingStopped(tokenId);
}
}
/**
@dev Changes the listed Cows' grazing statuses.
*/
function toggleGrazing(uint256[] calldata tokenIds) external {
uint256 n = tokenIds.length;
for (uint256 i = 0; i < n; ++i) {
toggleGrazing(tokenIds[i]);
}
}
/**
@notice Admin-only ability to terminate the grazing of a cow.
@dev Listing a cow while it is grazing is prohabited, but checking this at a contract level is
* impossible, so we have to monitor with an off-chian service the large marketplaces and
* terminate manually the grazing if needed. We have to do this since grazing cows could not
* be transfered, so enabling a listing of them could result false market prices.
*/
function expelFromGrazing(uint256 tokenId) external onlyRole(EXPULSION_ROLE) {
require(grazingStarted[tokenId] != 0, "cowlony: not grazing");
uint256 grazingTime = block.timestamp - grazingStarted[tokenId];
grazingTotal[tokenId] += grazingTime;
grazingStarted[tokenId] = 0;
if (grazingMax[tokenId] < grazingTime) {
grazingMax[tokenId] = grazingTime;
}
emit GrazingStopped(tokenId);
emit Expelled(tokenId);
}
// transfer revenues
/**
@notice Recipient of revenues.
*/
address payable public beneficiary;
/**
@notice Sets the recipient of revenues
*/
function setBeneficiary(address payable _beneficiary) public onlyOwner {
beneficiary = _beneficiary;
}
/**
@notice Send revenues to beneficiary
*/
function transferRevenues() external onlyOwner {
require(beneficiary != address(0), "No beneficiary address defined");
(bool success, ) = beneficiary.call{value: address(this).balance}("Sending revenues from cowlony");
require(success, "Transfer failed.");
}
/**
@notice Limits the COLLECTION_SIZE to the current totalSupply
*/
function burnUnsoldCows() external onlyOwner {
COLLECTION_SIZE = totalSupply();
}
function supportsInterface(bytes4 interfaceId) public view override(ERC721A, AccessControlEnumerable) returns (bool) {
return super.supportsInterface(interfaceId);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (access/AccessControlEnumerable.sol)
pragma solidity ^0.8.0;
import "./IAccessControlEnumerable.sol";
import "./AccessControl.sol";
import "../utils/structs/EnumerableSet.sol";
/**
* @dev Extension of {AccessControl} that allows enumerating the members of each role.
*/
abstract contract AccessControlEnumerable is IAccessControlEnumerable, AccessControl {
using EnumerableSet for EnumerableSet.AddressSet;
mapping(bytes32 => EnumerableSet.AddressSet) private _roleMembers;
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
return interfaceId == type(IAccessControlEnumerable).interfaceId || super.supportsInterface(interfaceId);
}
/**
* @dev Returns one of the accounts that have `role`. `index` must be a
* value between 0 and {getRoleMemberCount}, non-inclusive.
*
* Role bearers are not sorted in any particular way, and their ordering may
* change at any point.
*
* WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
* you perform all queries on the same block. See the following
* https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]
* for more information.
*/
function getRoleMember(bytes32 role, uint256 index) public view virtual override returns (address) {
return _roleMembers[role].at(index);
}
/**
* @dev Returns the number of accounts that have `role`. Can be used
* together with {getRoleMember} to enumerate all bearers of a role.
*/
function getRoleMemberCount(bytes32 role) public view virtual override returns (uint256) {
return _roleMembers[role].length();
}
/**
* @dev Overload {_grantRole} to track enumerable memberships
*/
function _grantRole(bytes32 role, address account) internal virtual override {
super._grantRole(role, account);
_roleMembers[role].add(account);
}
/**
* @dev Overload {_revokeRole} to track enumerable memberships
*/
function _revokeRole(bytes32 role, address account) internal virtual override {
super._revokeRole(role, account);
_roleMembers[role].remove(account);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (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 Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
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 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
// ERC721A Contracts v3.3.0
// Creator: Chiru Labs
pragma solidity ^0.8.4;
import './IERC721ABurnable.sol';
import '../ERC721A.sol';
/**
* @title ERC721A Burnable Token
* @dev ERC721A Token that can be irreversibly burned (destroyed).
*/
abstract contract ERC721ABurnable is ERC721A, IERC721ABurnable {
/**
* @dev Burns `tokenId`. See {ERC721A-_burn}.
*
* Requirements:
*
* - The caller must own `tokenId` or be an approved operator.
*/
function burn(uint256 tokenId) public virtual override {
_burn(tokenId, true);
}
}
// SPDX-License-Identifier: MIT
// Creator: https://github.com/cowlony-org
pragma solidity ^0.8.4;
import "@openzeppelin/contracts/utils/cryptography/ECDSA.sol";
/**
@title AllowlistSale contract
@dev AllowlistSale can manage multiple pre-defined sales with:
* - fixed or open ended time intervals
* - fixed price
* - quantity limit per transaction
* - allowlists with signature verification (we choose this method since it's more cost
* efficient with lists larger than 127 members than merkle trees)
* - public sales without signature verification
* This contracts aims to handle the needed verifications and also to provide a flexible dynamic
* configuration option.
*/
contract AllowlistSale {
using ECDSA for bytes32;
struct SaleConfig {
/**
@dev dates are in unix timestamp format, example: 1650230067
* one of the usable converters: https://www.epochconverter.com/
*/
uint256 startDate; // start of the sale 0 means it hasn't been started yet
uint256 endDate; // end of the sale 0 means it is open ended
uint256 price; // price of one item
uint256 quantityLimit; // how many tokens can be minted part of one transaction
address signer; // address that is used to sign the saleKeys
bool isPublicSale; // if it's true the signer will not be checked
bool checkUsedKeys; // if it's false saleKeys not stored after mint, making it cheaper
bool exists; // @dev to be able to delete sales
}
/**
@dev contains the added saleConfigs by sale ids
*/
mapping(uint256 => SaleConfig) public saleConfig;
/**
@dev Record of already-used signatures, used when every saleKey can be used only once
*/
mapping(bytes => bool) public usedKeys;
/**
@dev adds a new sale with the id and config to the available sales
*/
function _addSale(uint256 id, SaleConfig memory config) internal virtual {
saleConfig[id] = config;
}
/**
@dev deletes the saleConfig for the given id
*/
function _removeSale(uint256 id) internal virtual {
saleConfig[id].exists = false;
}
/**
@dev returns true if the current date is between the sale start and end date
* - start date is 0 means the sale is inactive -> returns false
* - end date is 0 means it is an open ended sale no need to check end date
*/
function verifySaleDate(uint256 saleId) internal virtual view {
SaleConfig memory sale = saleConfig[saleId];
require(sale.exists, "invalid saleId");
require(sale.startDate != 0 && block.timestamp > sale.startDate, "sale has not been started yet");
require(sale.endDate == 0 || block.timestamp < sale.endDate, "sale has been ended");
}
/**
@dev returns true if the provided saleKey is valid
* - address in the key matches with the sender's address
* - it is signed with the stored signer address
* - returns true when the sale is a public sale
*/
function verifySaleKey(bytes memory saleKey, uint256 saleId) internal virtual {
SaleConfig memory sale = saleConfig[saleId];
require(sale.isPublicSale ||
(!usedKeys[saleKey] && checkSignature(sale.signer, msg.sender, saleKey)),
"address with this key is not eligible to mint or saleKey has been already used");
if (saleConfig[saleId].checkUsedKeys) {
usedKeys[saleKey] = true;
}
}
/**
@dev verifies if the requested quantity is available for the sender
* - quantity should be less than the limit in the saleConfig
* - price should be at least the salePrice * quantity
*/
function verifyQuantity(uint256 quantity, uint256 saleId) internal virtual view {
require(quantity <= saleConfig[saleId].quantityLimit, "sale limit is exceeded for this transaction");
require(quantity * saleConfig[saleId].price <= msg.value, "not enough value was sent to complete the purchase");
}
/**
@dev verify runs the previous checks in one place to simplify the usage:
* - verifySaleDate
* - verifySaleKey
* - verifyQuantity & price
*/
function verify(uint256 quantity, bytes memory saleKey, uint256 saleId) internal virtual {
verifySaleDate(saleId);
verifySaleKey(saleKey, saleId);
verifyQuantity(quantity, saleId);
}
/**
@dev verifyPublicSale runs the previous checks without the saleKey verification:
* - verifySaleDate
* - verifyQuantity & price
*/
function verifyPublicSale(uint256 quantity, uint256 saleId) internal virtual view {
verifySaleDate(saleId);
verifyQuantity(quantity, saleId);
}
/**
@dev verifies the sent signature against the signer and sender address
*/
function checkSignature(address signer, address sender, bytes memory signature) private pure returns (bool) {
return signer ==
keccak256(
abi.encodePacked(
"\x19Ethereum Signed Message:\n32",
bytes32(uint256(uint160(sender))) // creates the 0x000000000000000000000000<sender> expected format
)
).recover(signature);
}
/**
@notice returns the sale config for a given saleId
*/
function getSale(uint256 saleId) public view returns (SaleConfig memory) {
require(saleConfig[saleId].exists, "invalid saleId");
return saleConfig[saleId];
}
}
// SPDX-License-Identifier: MIT
// Creator: https://github.com/cowlony-org
pragma solidity ^0.8.4;
/**
@dev Helpers to implement free listings on OpenSea
* implementation is based on the official guideline:
* https://docs.opensea.io/docs/1-structuring-your-smart-contract
*/
contract OwnableDelegateProxy { }
contract ProxyRegistry {
mapping(address => OwnableDelegateProxy) public proxies;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/IAccessControlEnumerable.sol)
pragma solidity ^0.8.0;
import "./IAccessControl.sol";
/**
* @dev External interface of AccessControlEnumerable declared to support ERC165 detection.
*/
interface IAccessControlEnumerable is IAccessControl {
/**
* @dev Returns one of the accounts that have `role`. `index` must be a
* value between 0 and {getRoleMemberCount}, non-inclusive.
*
* Role bearers are not sorted in any particular way, and their ordering may
* change at any point.
*
* WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure
* you perform all queries on the same block. See the following
* https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post]
* for more information.
*/
function getRoleMember(bytes32 role, uint256 index) external view returns (address);
/**
* @dev Returns the number of accounts that have `role`. Can be used
* together with {getRoleMember} to enumerate all bearers of a role.
*/
function getRoleMemberCount(bytes32 role) external view returns (uint256);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (access/AccessControl.sol)
pragma solidity ^0.8.0;
import "./IAccessControl.sol";
import "../utils/Context.sol";
import "../utils/Strings.sol";
import "../utils/introspection/ERC165.sol";
/**
* @dev Contract module that allows children to implement role-based access
* control mechanisms. This is a lightweight version that doesn't allow enumerating role
* members except through off-chain means by accessing the contract event logs. Some
* applications may benefit from on-chain enumerability, for those cases see
* {AccessControlEnumerable}.
*
* Roles are referred to by their `bytes32` identifier. These should be exposed
* in the external API and be unique. The best way to achieve this is by
* using `public constant` hash digests:
*
* ```
* bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
* ```
*
* Roles can be used to represent a set of permissions. To restrict access to a
* function call, use {hasRole}:
*
* ```
* function foo() public {
* require(hasRole(MY_ROLE, msg.sender));
* ...
* }
* ```
*
* Roles can be granted and revoked dynamically via the {grantRole} and
* {revokeRole} functions. Each role has an associated admin role, and only
* accounts that have a role's admin role can call {grantRole} and {revokeRole}.
*
* By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
* that only accounts with this role will be able to grant or revoke other
* roles. More complex role relationships can be created by using
* {_setRoleAdmin}.
*
* WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
* grant and revoke this role. Extra precautions should be taken to secure
* accounts that have been granted it.
*/
abstract contract AccessControl is Context, IAccessControl, ERC165 {
struct RoleData {
mapping(address => bool) members;
bytes32 adminRole;
}
mapping(bytes32 => RoleData) private _roles;
bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
/**
* @dev Modifier that checks that an account has a specific role. Reverts
* with a standardized message including the required role.
*
* The format of the revert reason is given by the following regular expression:
*
* /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
*
* _Available since v4.1._
*/
modifier onlyRole(bytes32 role) {
_checkRole(role);
_;
}
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);
}
/**
* @dev Returns `true` if `account` has been granted `role`.
*/
function hasRole(bytes32 role, address account) public view virtual override returns (bool) {
return _roles[role].members[account];
}
/**
* @dev Revert with a standard message if `_msgSender()` is missing `role`.
* Overriding this function changes the behavior of the {onlyRole} modifier.
*
* Format of the revert message is described in {_checkRole}.
*
* _Available since v4.6._
*/
function _checkRole(bytes32 role) internal view virtual {
_checkRole(role, _msgSender());
}
/**
* @dev Revert with a standard message if `account` is missing `role`.
*
* The format of the revert reason is given by the following regular expression:
*
* /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
*/
function _checkRole(bytes32 role, address account) internal view virtual {
if (!hasRole(role, account)) {
revert(
string(
abi.encodePacked(
"AccessControl: account ",
Strings.toHexString(uint160(account), 20),
" is missing role ",
Strings.toHexString(uint256(role), 32)
)
)
);
}
}
/**
* @dev Returns the admin role that controls `role`. See {grantRole} and
* {revokeRole}.
*
* To change a role's admin, use {_setRoleAdmin}.
*/
function getRoleAdmin(bytes32 role) public view virtual override returns (bytes32) {
return _roles[role].adminRole;
}
/**
* @dev Grants `role` to `account`.
*
* If `account` had not been already granted `role`, emits a {RoleGranted}
* event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*/
function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
_grantRole(role, account);
}
/**
* @dev Revokes `role` from `account`.
*
* If `account` had been granted `role`, emits a {RoleRevoked} event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*/
function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
_revokeRole(role, account);
}
/**
* @dev Revokes `role` from the calling account.
*
* Roles are often managed via {grantRole} and {revokeRole}: this function's
* purpose is to provide a mechanism for accounts to lose their privileges
* if they are compromised (such as when a trusted device is misplaced).
*
* If the calling account had been revoked `role`, emits a {RoleRevoked}
* event.
*
* Requirements:
*
* - the caller must be `account`.
*/
function renounceRole(bytes32 role, address account) public virtual override {
require(account == _msgSender(), "AccessControl: can only renounce roles for self");
_revokeRole(role, account);
}
/**
* @dev Grants `role` to `account`.
*
* If `account` had not been already granted `role`, emits a {RoleGranted}
* event. Note that unlike {grantRole}, this function doesn't perform any
* checks on the calling account.
*
* [WARNING]
* ====
* This function should only be called from the constructor when setting
* up the initial roles for the system.
*
* Using this function in any other way is effectively circumventing the admin
* system imposed by {AccessControl}.
* ====
*
* NOTE: This function is deprecated in favor of {_grantRole}.
*/
function _setupRole(bytes32 role, address account) internal virtual {
_grantRole(role, account);
}
/**
* @dev Sets `adminRole` as ``role``'s admin role.
*
* Emits a {RoleAdminChanged} event.
*/
function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
bytes32 previousAdminRole = getRoleAdmin(role);
_roles[role].adminRole = adminRole;
emit RoleAdminChanged(role, previousAdminRole, adminRole);
}
/**
* @dev Grants `role` to `account`.
*
* Internal function without access restriction.
*/
function _grantRole(bytes32 role, address account) internal virtual {
if (!hasRole(role, account)) {
_roles[role].members[account] = true;
emit RoleGranted(role, account, _msgSender());
}
}
/**
* @dev Revokes `role` from `account`.
*
* Internal function without access restriction.
*/
function _revokeRole(bytes32 role, address account) internal virtual {
if (hasRole(role, account)) {
_roles[role].members[account] = false;
emit RoleRevoked(role, account, _msgSender());
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (utils/structs/EnumerableSet.sol)
pragma solidity ^0.8.0;
/**
* @dev Library for managing
* https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
* types.
*
* Sets have the following properties:
*
* - Elements are added, removed, and checked for existence in constant time
* (O(1)).
* - Elements are enumerated in O(n). No guarantees are made on the ordering.
*
* ```
* contract Example {
* // Add the library methods
* using EnumerableSet for EnumerableSet.AddressSet;
*
* // Declare a set state variable
* EnumerableSet.AddressSet private mySet;
* }
* ```
*
* As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
* and `uint256` (`UintSet`) are supported.
*/
library EnumerableSet {
// To implement this library for multiple types with as little code
// repetition as possible, we write it in terms of a generic Set type with
// bytes32 values.
// The Set implementation uses private functions, and user-facing
// implementations (such as AddressSet) are just wrappers around the
// underlying Set.
// This means that we can only create new EnumerableSets for types that fit
// in bytes32.
struct Set {
// Storage of set values
bytes32[] _values;
// Position of the value in the `values` array, plus 1 because index 0
// means a value is not in the set.
mapping(bytes32 => uint256) _indexes;
}
/**
* @dev Add a value to a set. O(1).
*
* Returns true if the value was added to the set, that is if it was not
* already present.
*/
function _add(Set storage set, bytes32 value) private returns (bool) {
if (!_contains(set, value)) {
set._values.push(value);
// The value is stored at length-1, but we add 1 to all indexes
// and use 0 as a sentinel value
set._indexes[value] = set._values.length;
return true;
} else {
return false;
}
}
/**
* @dev Removes a value from a set. O(1).
*
* Returns true if the value was removed from the set, that is if it was
* present.
*/
function _remove(Set storage set, bytes32 value) private returns (bool) {
// We read and store the value's index to prevent multiple reads from the same storage slot
uint256 valueIndex = set._indexes[value];
if (valueIndex != 0) {
// Equivalent to contains(set, value)
// To delete an element from the _values array in O(1), we swap the element to delete with the last one in
// the array, and then remove the last element (sometimes called as 'swap and pop').
// This modifies the order of the array, as noted in {at}.
uint256 toDeleteIndex = valueIndex - 1;
uint256 lastIndex = set._values.length - 1;
if (lastIndex != toDeleteIndex) {
bytes32 lastValue = set._values[lastIndex];
// Move the last value to the index where the value to delete is
set._values[toDeleteIndex] = lastValue;
// Update the index for the moved value
set._indexes[lastValue] = valueIndex; // Replace lastValue's index to valueIndex
}
// Delete the slot where the moved value was stored
set._values.pop();
// Delete the index for the deleted slot
delete set._indexes[value];
return true;
} else {
return false;
}
}
/**
* @dev Returns true if the value is in the set. O(1).
*/
function _contains(Set storage set, bytes32 value) private view returns (bool) {
return set._indexes[value] != 0;
}
/**
* @dev Returns the number of values on the set. O(1).
*/
function _length(Set storage set) private view returns (uint256) {
return set._values.length;
}
/**
* @dev Returns the value stored at position `index` in the set. O(1).
*
* Note that there are no guarantees on the ordering of values inside the
* array, and it may change when more values are added or removed.
*
* Requirements:
*
* - `index` must be strictly less than {length}.
*/
function _at(Set storage set, uint256 index) private view returns (bytes32) {
return set._values[index];
}
/**
* @dev Return the entire set in an array
*
* WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
* to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
* this function has an unbounded cost, and using it as part of a state-changing function may render the function
* uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
*/
function _values(Set storage set) private view returns (bytes32[] memory) {
return set._values;
}
// Bytes32Set
struct Bytes32Set {
Set _inner;
}
/**
* @dev Add a value to a set. O(1).
*
* Returns true if the value was added to the set, that is if it was not
* already present.
*/
function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
return _add(set._inner, value);
}
/**
* @dev Removes a value from a set. O(1).
*
* Returns true if the value was removed from the set, that is if it was
* present.
*/
function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
return _remove(set._inner, value);
}
/**
* @dev Returns true if the value is in the set. O(1).
*/
function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
return _contains(set._inner, value);
}
/**
* @dev Returns the number of values in the set. O(1).
*/
function length(Bytes32Set storage set) internal view returns (uint256) {
return _length(set._inner);
}
/**
* @dev Returns the value stored at position `index` in the set. O(1).
*
* Note that there are no guarantees on the ordering of values inside the
* array, and it may change when more values are added or removed.
*
* Requirements:
*
* - `index` must be strictly less than {length}.
*/
function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
return _at(set._inner, index);
}
/**
* @dev Return the entire set in an array
*
* WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
* to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
* this function has an unbounded cost, and using it as part of a state-changing function may render the function
* uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
*/
function values(Bytes32Set storage set) internal view returns (bytes32[] memory) {
return _values(set._inner);
}
// AddressSet
struct AddressSet {
Set _inner;
}
/**
* @dev Add a value to a set. O(1).
*
* Returns true if the value was added to the set, that is if it was not
* already present.
*/
function add(AddressSet storage set, address value) internal returns (bool) {
return _add(set._inner, bytes32(uint256(uint160(value))));
}
/**
* @dev Removes a value from a set. O(1).
*
* Returns true if the value was removed from the set, that is if it was
* present.
*/
function remove(AddressSet storage set, address value) internal returns (bool) {
return _remove(set._inner, bytes32(uint256(uint160(value))));
}
/**
* @dev Returns true if the value is in the set. O(1).
*/
function contains(AddressSet storage set, address value) internal view returns (bool) {
return _contains(set._inner, bytes32(uint256(uint160(value))));
}
/**
* @dev Returns the number of values in the set. O(1).
*/
function length(AddressSet storage set) internal view returns (uint256) {
return _length(set._inner);
}
/**
* @dev Returns the value stored at position `index` in the set. O(1).
*
* Note that there are no guarantees on the ordering of values inside the
* array, and it may change when more values are added or removed.
*
* Requirements:
*
* - `index` must be strictly less than {length}.
*/
function at(AddressSet storage set, uint256 index) internal view returns (address) {
return address(uint160(uint256(_at(set._inner, index))));
}
/**
* @dev Return the entire set in an array
*
* WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
* to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
* this function has an unbounded cost, and using it as part of a state-changing function may render the function
* uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
*/
function values(AddressSet storage set) internal view returns (address[] memory) {
bytes32[] memory store = _values(set._inner);
address[] memory result;
assembly {
result := store
}
return result;
}
// UintSet
struct UintSet {
Set _inner;
}
/**
* @dev Add a value to a set. O(1).
*
* Returns true if the value was added to the set, that is if it was not
* already present.
*/
function add(UintSet storage set, uint256 value) internal returns (bool) {
return _add(set._inner, bytes32(value));
}
/**
* @dev Removes a value from a set. O(1).
*
* Returns true if the value was removed from the set, that is if it was
* present.
*/
function remove(UintSet storage set, uint256 value) internal returns (bool) {
return _remove(set._inner, bytes32(value));
}
/**
* @dev Returns true if the value is in the set. O(1).
*/
function contains(UintSet storage set, uint256 value) internal view returns (bool) {
return _contains(set._inner, bytes32(value));
}
/**
* @dev Returns the number of values on the set. O(1).
*/
function length(UintSet storage set) internal view returns (uint256) {
return _length(set._inner);
}
/**
* @dev Returns the value stored at position `index` in the set. O(1).
*
* Note that there are no guarantees on the ordering of values inside the
* array, and it may change when more values are added or removed.
*
* Requirements:
*
* - `index` must be strictly less than {length}.
*/
function at(UintSet storage set, uint256 index) internal view returns (uint256) {
return uint256(_at(set._inner, index));
}
/**
* @dev Return the entire set in an array
*
* WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed
* to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that
* this function has an unbounded cost, and using it as part of a state-changing function may render the function
* uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block.
*/
function values(UintSet storage set) internal view returns (uint256[] memory) {
bytes32[] memory store = _values(set._inner);
uint256[] memory result;
assembly {
result := store
}
return result;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)
pragma solidity ^0.8.0;
/**
* @dev External interface of AccessControl declared to support ERC165 detection.
*/
interface IAccessControl {
/**
* @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
*
* `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
* {RoleAdminChanged} not being emitted signaling this.
*
* _Available since v3.1._
*/
event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
/**
* @dev Emitted when `account` is granted `role`.
*
* `sender` is the account that originated the contract call, an admin role
* bearer except when using {AccessControl-_setupRole}.
*/
event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
/**
* @dev Emitted when `account` is revoked `role`.
*
* `sender` is the account that originated the contract call:
* - if using `revokeRole`, it is the admin role bearer
* - if using `renounceRole`, it is the role bearer (i.e. `account`)
*/
event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
/**
* @dev Returns `true` if `account` has been granted `role`.
*/
function hasRole(bytes32 role, address account) external view returns (bool);
/**
* @dev Returns the admin role that controls `role`. See {grantRole} and
* {revokeRole}.
*
* To change a role's admin, use {AccessControl-_setRoleAdmin}.
*/
function getRoleAdmin(bytes32 role) external view returns (bytes32);
/**
* @dev Grants `role` to `account`.
*
* If `account` had not been already granted `role`, emits a {RoleGranted}
* event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*/
function grantRole(bytes32 role, address account) external;
/**
* @dev Revokes `role` from `account`.
*
* If `account` had been granted `role`, emits a {RoleRevoked} event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*/
function revokeRole(bytes32 role, address account) external;
/**
* @dev Revokes `role` from the calling account.
*
* Roles are often managed via {grantRole} and {revokeRole}: this function's
* purpose is to provide a mechanism for accounts to lose their privileges
* if they are compromised (such as when a trusted device is misplaced).
*
* If the calling account had been granted `role`, emits a {RoleRevoked}
* event.
*
* Requirements:
*
* - the caller must be `account`.
*/
function renounceRole(bytes32 role, address account) 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 v4.4.1 (utils/Strings.sol)
pragma solidity ^0.8.0;
/**
* @dev String operations.
*/
library Strings {
bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
/**
* @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);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
pragma solidity ^0.8.0;
import "./IERC165.sol";
/**
* @dev Implementation of the {IERC165} interface.
*
* Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
* for the additional interface id that will be supported. For example:
*
* ```solidity
* function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
* return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
* }
* ```
*
* Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
*/
abstract contract ERC165 is IERC165 {
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
return interfaceId == type(IERC165).interfaceId;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC165 standard, as defined in the
* https://eips.ethereum.org/EIPS/eip-165[EIP].
*
* Implementers can declare support of contract interfaces, which can then be
* queried by others ({ERC165Checker}).
*
* For an implementation, see {ERC165}.
*/
interface IERC165 {
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
* to learn more about how these ids are created.
*
* This function call must use less than 30 000 gas.
*/
function supportsInterface(bytes4 interfaceId) external view returns (bool);
}
// SPDX-License-Identifier: MIT
// ERC721A Contracts v3.3.0
// Creator: Chiru Labs
pragma solidity ^0.8.4;
import '../IERC721A.sol';
/**
* @dev Interface of an ERC721ABurnable compliant contract.
*/
interface IERC721ABurnable is IERC721A {
/**
* @dev Burns `tokenId`. See {ERC721A-_burn}.
*
* Requirements:
*
* - The caller must own `tokenId` or be an approved operator.
*/
function burn(uint256 tokenId) external;
}
// SPDX-License-Identifier: MIT
// ERC721A Contracts v3.3.0
// Creator: Chiru Labs
pragma solidity ^0.8.4;
import './IERC721A.sol';
import '@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol';
import '@openzeppelin/contracts/utils/Address.sol';
import '@openzeppelin/contracts/utils/Context.sol';
import '@openzeppelin/contracts/utils/Strings.sol';
import '@openzeppelin/contracts/utils/introspection/ERC165.sol';
/**
* @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
* the Metadata extension. Built to optimize for lower gas during batch mints.
*
* Assumes serials are sequentially minted starting at _startTokenId() (defaults to 0, e.g. 0, 1, 2, 3..).
*
* Assumes that an owner cannot have more than 2**64 - 1 (max value of uint64) of supply.
*
* Assumes that the maximum token id cannot exceed 2**256 - 1 (max value of uint256).
*/
contract ERC721A is Context, ERC165, IERC721A {
using Address for address;
using Strings for uint256;
// The tokenId of the next token to be minted.
uint256 internal _currentIndex;
// The number of tokens burned.
uint256 internal _burnCounter;
// Token name
string private _name;
// Token symbol
string private _symbol;
// Mapping from token ID to ownership details
// An empty struct value does not necessarily mean the token is unowned. See _ownershipOf implementation for details.
mapping(uint256 => TokenOwnership) internal _ownerships;
// Mapping owner address to address data
mapping(address => AddressData) private _addressData;
// 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;
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
_currentIndex = _startTokenId();
}
/**
* To change the starting tokenId, please override this function.
*/
function _startTokenId() internal view virtual returns (uint256) {
return 0;
}
/**
* @dev Burned tokens are calculated here, use _totalMinted() if you want to count just minted tokens.
*/
function totalSupply() public view override returns (uint256) {
// Counter underflow is impossible as _burnCounter cannot be incremented
// more than _currentIndex - _startTokenId() times
unchecked {
return _currentIndex - _burnCounter - _startTokenId();
}
}
/**
* Returns the total amount of tokens minted in the contract.
*/
function _totalMinted() internal view returns (uint256) {
// Counter underflow is impossible as _currentIndex does not decrement,
// and it is initialized to _startTokenId()
unchecked {
return _currentIndex - _startTokenId();
}
}
/**
* @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 override returns (uint256) {
if (owner == address(0)) revert BalanceQueryForZeroAddress();
return uint256(_addressData[owner].balance);
}
/**
* Returns the number of tokens minted by `owner`.
*/
function _numberMinted(address owner) internal view returns (uint256) {
return uint256(_addressData[owner].numberMinted);
}
/**
* Returns the number of tokens burned by or on behalf of `owner`.
*/
function _numberBurned(address owner) internal view returns (uint256) {
return uint256(_addressData[owner].numberBurned);
}
/**
* Returns the auxillary data for `owner`. (e.g. number of whitelist mint slots used).
*/
function _getAux(address owner) internal view returns (uint64) {
return _addressData[owner].aux;
}
/**
* Sets the auxillary data for `owner`. (e.g. number of whitelist mint slots used).
* If there are multiple variables, please pack them into a uint64.
*/
function _setAux(address owner, uint64 aux) internal {
_addressData[owner].aux = aux;
}
/**
* Gas spent here starts off proportional to the maximum mint batch size.
* It gradually moves to O(1) as tokens get transferred around in the collection over time.
*/
function _ownershipOf(uint256 tokenId) internal view returns (TokenOwnership memory) {
uint256 curr = tokenId;
unchecked {
if (_startTokenId() <= curr) if (curr < _currentIndex) {
TokenOwnership memory ownership = _ownerships[curr];
if (!ownership.burned) {
if (ownership.addr != address(0)) {
return ownership;
}
// Invariant:
// There will always be an ownership that has an address and is not burned
// before an ownership that does not have an address and is not burned.
// Hence, curr will not underflow.
while (true) {
curr--;
ownership = _ownerships[curr];
if (ownership.addr != address(0)) {
return ownership;
}
}
}
}
}
revert OwnerQueryForNonexistentToken();
}
/**
* @dev See {IERC721-ownerOf}.
*/
function ownerOf(uint256 tokenId) public view override returns (address) {
return _ownershipOf(tokenId).addr;
}
/**
* @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) {
if (!_exists(tokenId)) revert URIQueryForNonexistentToken();
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 overriden in child contracts.
*/
function _baseURI() internal view virtual returns (string memory) {
return '';
}
/**
* @dev See {IERC721-approve}.
*/
function approve(address to, uint256 tokenId) public override {
address owner = ERC721A.ownerOf(tokenId);
if (to == owner) revert ApprovalToCurrentOwner();
if (_msgSender() != owner) if(!isApprovedForAll(owner, _msgSender())) {
revert ApprovalCallerNotOwnerNorApproved();
}
_approve(to, tokenId, owner);
}
/**
* @dev See {IERC721-getApproved}.
*/
function getApproved(uint256 tokenId) public view override returns (address) {
if (!_exists(tokenId)) revert ApprovalQueryForNonexistentToken();
return _tokenApprovals[tokenId];
}
/**
* @dev See {IERC721-setApprovalForAll}.
*/
function setApprovalForAll(address operator, bool approved) public virtual override {
if (operator == _msgSender()) revert ApproveToCaller();
_operatorApprovals[_msgSender()][operator] = approved;
emit ApprovalForAll(_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 {
_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 {
_transfer(from, to, tokenId);
if (to.isContract()) if(!_checkContractOnERC721Received(from, to, tokenId, _data)) {
revert TransferToNonERC721ReceiverImplementer();
}
}
/**
* @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`),
*/
function _exists(uint256 tokenId) internal view returns (bool) {
return _startTokenId() <= tokenId && tokenId < _currentIndex && !_ownerships[tokenId].burned;
}
/**
* @dev Equivalent to `_safeMint(to, quantity, '')`.
*/
function _safeMint(address to, uint256 quantity) internal {
_safeMint(to, quantity, '');
}
/**
* @dev Safely mints `quantity` tokens and transfers them to `to`.
*
* Requirements:
*
* - If `to` refers to a smart contract, it must implement
* {IERC721Receiver-onERC721Received}, which is called for each safe transfer.
* - `quantity` must be greater than 0.
*
* Emits a {Transfer} event.
*/
function _safeMint(
address to,
uint256 quantity,
bytes memory _data
) internal {
uint256 startTokenId = _currentIndex;
if (to == address(0)) revert MintToZeroAddress();
if (quantity == 0) revert MintZeroQuantity();
_beforeTokenTransfers(address(0), to, startTokenId, quantity);
// Overflows are incredibly unrealistic.
// balance or numberMinted overflow if current value of either + quantity > 1.8e19 (2**64) - 1
// updatedIndex overflows if _currentIndex + quantity > 1.2e77 (2**256) - 1
unchecked {
_addressData[to].balance += uint64(quantity);
_addressData[to].numberMinted += uint64(quantity);
_ownerships[startTokenId].addr = to;
_ownerships[startTokenId].startTimestamp = uint64(block.timestamp);
uint256 updatedIndex = startTokenId;
uint256 end = updatedIndex + quantity;
if (to.isContract()) {
do {
emit Transfer(address(0), to, updatedIndex);
if (!_checkContractOnERC721Received(address(0), to, updatedIndex++, _data)) {
revert TransferToNonERC721ReceiverImplementer();
}
} while (updatedIndex < end);
// Reentrancy protection
if (_currentIndex != startTokenId) revert();
} else {
do {
emit Transfer(address(0), to, updatedIndex++);
} while (updatedIndex < end);
}
_currentIndex = updatedIndex;
}
_afterTokenTransfers(address(0), to, startTokenId, quantity);
}
/**
* @dev Mints `quantity` tokens and transfers them to `to`.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - `quantity` must be greater than 0.
*
* Emits a {Transfer} event.
*/
function _mint(address to, uint256 quantity) internal {
uint256 startTokenId = _currentIndex;
if (to == address(0)) revert MintToZeroAddress();
if (quantity == 0) revert MintZeroQuantity();
_beforeTokenTransfers(address(0), to, startTokenId, quantity);
// Overflows are incredibly unrealistic.
// balance or numberMinted overflow if current value of either + quantity > 1.8e19 (2**64) - 1
// updatedIndex overflows if _currentIndex + quantity > 1.2e77 (2**256) - 1
unchecked {
_addressData[to].balance += uint64(quantity);
_addressData[to].numberMinted += uint64(quantity);
_ownerships[startTokenId].addr = to;
_ownerships[startTokenId].startTimestamp = uint64(block.timestamp);
uint256 updatedIndex = startTokenId;
uint256 end = updatedIndex + quantity;
do {
emit Transfer(address(0), to, updatedIndex++);
} while (updatedIndex < end);
_currentIndex = updatedIndex;
}
_afterTokenTransfers(address(0), to, startTokenId, quantity);
}
/**
* @dev Transfers `tokenId` from `from` to `to`.
*
* 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
) private {
TokenOwnership memory prevOwnership = _ownershipOf(tokenId);
if (prevOwnership.addr != from) revert TransferFromIncorrectOwner();
bool isApprovedOrOwner = (_msgSender() == from ||
isApprovedForAll(from, _msgSender()) ||
getApproved(tokenId) == _msgSender());
if (!isApprovedOrOwner) revert TransferCallerNotOwnerNorApproved();
if (to == address(0)) revert TransferToZeroAddress();
_beforeTokenTransfers(from, to, tokenId, 1);
// Clear approvals from the previous owner
_approve(address(0), tokenId, from);
// Underflow of the sender's balance is impossible because we check for
// ownership above and the recipient's balance can't realistically overflow.
// Counter overflow is incredibly unrealistic as tokenId would have to be 2**256.
unchecked {
_addressData[from].balance -= 1;
_addressData[to].balance += 1;
TokenOwnership storage currSlot = _ownerships[tokenId];
currSlot.addr = to;
currSlot.startTimestamp = uint64(block.timestamp);
// If the ownership slot of tokenId+1 is not explicitly set, that means the transfer initiator owns it.
// Set the slot of tokenId+1 explicitly in storage to maintain correctness for ownerOf(tokenId+1) calls.
uint256 nextTokenId = tokenId + 1;
TokenOwnership storage nextSlot = _ownerships[nextTokenId];
if (nextSlot.addr == address(0)) {
// This will suffice for checking _exists(nextTokenId),
// as a burned slot cannot contain the zero address.
if (nextTokenId != _currentIndex) {
nextSlot.addr = from;
nextSlot.startTimestamp = prevOwnership.startTimestamp;
}
}
}
emit Transfer(from, to, tokenId);
_afterTokenTransfers(from, to, tokenId, 1);
}
/**
* @dev Equivalent to `_burn(tokenId, false)`.
*/
function _burn(uint256 tokenId) internal virtual {
_burn(tokenId, false);
}
/**
* @dev Destroys `tokenId`.
* The approval is cleared when the token is burned.
*
* Requirements:
*
* - `tokenId` must exist.
*
* Emits a {Transfer} event.
*/
function _burn(uint256 tokenId, bool approvalCheck) internal virtual {
TokenOwnership memory prevOwnership = _ownershipOf(tokenId);
address from = prevOwnership.addr;
if (approvalCheck) {
bool isApprovedOrOwner = (_msgSender() == from ||
isApprovedForAll(from, _msgSender()) ||
getApproved(tokenId) == _msgSender());
if (!isApprovedOrOwner) revert TransferCallerNotOwnerNorApproved();
}
_beforeTokenTransfers(from, address(0), tokenId, 1);
// Clear approvals from the previous owner
_approve(address(0), tokenId, from);
// Underflow of the sender's balance is impossible because we check for
// ownership above and the recipient's balance can't realistically overflow.
// Counter overflow is incredibly unrealistic as tokenId would have to be 2**256.
unchecked {
AddressData storage addressData = _addressData[from];
addressData.balance -= 1;
addressData.numberBurned += 1;
// Keep track of who burned the token, and the timestamp of burning.
TokenOwnership storage currSlot = _ownerships[tokenId];
currSlot.addr = from;
currSlot.startTimestamp = uint64(block.timestamp);
currSlot.burned = true;
// If the ownership slot of tokenId+1 is not explicitly set, that means the burn initiator owns it.
// Set the slot of tokenId+1 explicitly in storage to maintain correctness for ownerOf(tokenId+1) calls.
uint256 nextTokenId = tokenId + 1;
TokenOwnership storage nextSlot = _ownerships[nextTokenId];
if (nextSlot.addr == address(0)) {
// This will suffice for checking _exists(nextTokenId),
// as a burned slot cannot contain the zero address.
if (nextTokenId != _currentIndex) {
nextSlot.addr = from;
nextSlot.startTimestamp = prevOwnership.startTimestamp;
}
}
}
emit Transfer(from, address(0), tokenId);
_afterTokenTransfers(from, address(0), tokenId, 1);
// Overflow not possible, as _burnCounter cannot be exceed _currentIndex times.
unchecked {
_burnCounter++;
}
}
/**
* @dev Approve `to` to operate on `tokenId`
*
* Emits a {Approval} event.
*/
function _approve(
address to,
uint256 tokenId,
address owner
) private {
_tokenApprovals[tokenId] = to;
emit Approval(owner, to, tokenId);
}
/**
* @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target 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 _checkContractOnERC721Received(
address from,
address to,
uint256 tokenId,
bytes memory _data
) private returns (bool) {
try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, _data) returns (bytes4 retval) {
return retval == IERC721Receiver(to).onERC721Received.selector;
} catch (bytes memory reason) {
if (reason.length == 0) {
revert TransferToNonERC721ReceiverImplementer();
} else {
assembly {
revert(add(32, reason), mload(reason))
}
}
}
}
/**
* @dev Hook that is called before a set of serially-ordered token ids are about to be transferred. This includes minting.
* And also called before burning one token.
*
* startTokenId - the first token id to be transferred
* quantity - the amount to be transferred
*
* 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, `tokenId` will be burned by `from`.
* - `from` and `to` are never both zero.
*/
function _beforeTokenTransfers(
address from,
address to,
uint256 startTokenId,
uint256 quantity
) internal virtual {}
/**
* @dev Hook that is called after a set of serially-ordered token ids have been transferred. This includes
* minting.
* And also called after one token has been burned.
*
* startTokenId - the first token id to be transferred
* quantity - the amount to be transferred
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, `from`'s `tokenId` has been
* transferred to `to`.
* - When `from` is zero, `tokenId` has been minted for `to`.
* - When `to` is zero, `tokenId` has been burned by `from`.
* - `from` and `to` are never both zero.
*/
function _afterTokenTransfers(
address from,
address to,
uint256 startTokenId,
uint256 quantity
) internal virtual {}
}
// SPDX-License-Identifier: MIT
// ERC721A Contracts v3.3.0
// Creator: Chiru Labs
pragma solidity ^0.8.4;
import '@openzeppelin/contracts/token/ERC721/IERC721.sol';
import '@openzeppelin/contracts/token/ERC721/extensions/IERC721Metadata.sol';
/**
* @dev Interface of an ERC721A compliant contract.
*/
interface IERC721A is IERC721, IERC721Metadata {
/**
* The caller must own the token or be an approved operator.
*/
error ApprovalCallerNotOwnerNorApproved();
/**
* The token does not exist.
*/
error ApprovalQueryForNonexistentToken();
/**
* The caller cannot approve to their own address.
*/
error ApproveToCaller();
/**
* The caller cannot approve to the current owner.
*/
error ApprovalToCurrentOwner();
/**
* Cannot query the balance for the zero address.
*/
error BalanceQueryForZeroAddress();
/**
* Cannot mint to the zero address.
*/
error MintToZeroAddress();
/**
* The quantity of tokens minted must be more than zero.
*/
error MintZeroQuantity();
/**
* The token does not exist.
*/
error OwnerQueryForNonexistentToken();
/**
* The caller must own the token or be an approved operator.
*/
error TransferCallerNotOwnerNorApproved();
/**
* The token must be owned by `from`.
*/
error TransferFromIncorrectOwner();
/**
* Cannot safely transfer to a contract that does not implement the ERC721Receiver interface.
*/
error TransferToNonERC721ReceiverImplementer();
/**
* Cannot transfer to the zero address.
*/
error TransferToZeroAddress();
/**
* The token does not exist.
*/
error URIQueryForNonexistentToken();
// Compiler will pack this into a single 256bit word.
struct TokenOwnership {
// The address of the owner.
address addr;
// Keeps track of the start time of ownership with minimal overhead for tokenomics.
uint64 startTimestamp;
// Whether the token has been burned.
bool burned;
}
// Compiler will pack this into a single 256bit word.
struct AddressData {
// Realistically, 2**64-1 is more than enough.
uint64 balance;
// Keeps track of mint count with minimal overhead for tokenomics.
uint64 numberMinted;
// Keeps track of burn count with minimal overhead for tokenomics.
uint64 numberBurned;
// For miscellaneous variable(s) pertaining to the address
// (e.g. number of whitelist mint slots used).
// If there are multiple variables, please pack them into a uint64.
uint64 aux;
}
/**
* @dev Returns the total amount of tokens stored by the contract.
*
* Burned tokens are calculated here, use `_totalMinted()` if you want to count just minted tokens.
*/
function totalSupply() external view returns (uint256);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (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 be 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 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);
}
// 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 v4.5.0) (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
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/cryptography/ECDSA.sol)
pragma solidity ^0.8.0;
import "../Strings.sol";
/**
* @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
*
* These functions can be used to verify that a message was signed by the holder
* of the private keys of a given address.
*/
library ECDSA {
enum RecoverError {
NoError,
InvalidSignature,
InvalidSignatureLength,
InvalidSignatureS,
InvalidSignatureV
}
function _throwError(RecoverError error) private pure {
if (error == RecoverError.NoError) {
return; // no error: do nothing
} else if (error == RecoverError.InvalidSignature) {
revert("ECDSA: invalid signature");
} else if (error == RecoverError.InvalidSignatureLength) {
revert("ECDSA: invalid signature length");
} else if (error == RecoverError.InvalidSignatureS) {
revert("ECDSA: invalid signature 's' value");
} else if (error == RecoverError.InvalidSignatureV) {
revert("ECDSA: invalid signature 'v' value");
}
}
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature` or error string. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*
* Documentation for signature generation:
* - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
* - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
*
* _Available since v4.3._
*/
function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
// Check the signature length
// - case 65: r,s,v signature (standard)
// - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._
if (signature.length == 65) {
bytes32 r;
bytes32 s;
uint8 v;
// ecrecover takes the signature parameters, and the only way to get them
// currently is to use assembly.
assembly {
r := mload(add(signature, 0x20))
s := mload(add(signature, 0x40))
v := byte(0, mload(add(signature, 0x60)))
}
return tryRecover(hash, v, r, s);
} else if (signature.length == 64) {
bytes32 r;
bytes32 vs;
// ecrecover takes the signature parameters, and the only way to get them
// currently is to use assembly.
assembly {
r := mload(add(signature, 0x20))
vs := mload(add(signature, 0x40))
}
return tryRecover(hash, r, vs);
} else {
return (address(0), RecoverError.InvalidSignatureLength);
}
}
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature`. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*/
function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, signature);
_throwError(error);
return recovered;
}
/**
* @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
*
* See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
*
* _Available since v4.3._
*/
function tryRecover(
bytes32 hash,
bytes32 r,
bytes32 vs
) internal pure returns (address, RecoverError) {
bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
uint8 v = uint8((uint256(vs) >> 255) + 27);
return tryRecover(hash, v, r, s);
}
/**
* @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
*
* _Available since v4.2._
*/
function recover(
bytes32 hash,
bytes32 r,
bytes32 vs
) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, r, vs);
_throwError(error);
return recovered;
}
/**
* @dev Overload of {ECDSA-tryRecover} that receives the `v`,
* `r` and `s` signature fields separately.
*
* _Available since v4.3._
*/
function tryRecover(
bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internal pure returns (address, RecoverError) {
// EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
// unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
// the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
// signatures from current libraries generate a unique signature with an s-value in the lower half order.
//
// If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
// with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
// vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
// these malleable signatures as well.
if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
return (address(0), RecoverError.InvalidSignatureS);
}
if (v != 27 && v != 28) {
return (address(0), RecoverError.InvalidSignatureV);
}
// If the signature is valid (and not malleable), return the signer address
address signer = ecrecover(hash, v, r, s);
if (signer == address(0)) {
return (address(0), RecoverError.InvalidSignature);
}
return (signer, RecoverError.NoError);
}
/**
* @dev Overload of {ECDSA-recover} that receives the `v`,
* `r` and `s` signature fields separately.
*/
function recover(
bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, v, r, s);
_throwError(error);
return recovered;
}
/**
* @dev Returns an Ethereum Signed Message, created from a `hash`. This
* produces hash corresponding to the one signed with the
* https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
* JSON-RPC method as part of EIP-191.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
// 32 is the length in bytes of hash,
// enforced by the type signature above
return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
}
/**
* @dev Returns an Ethereum Signed Message, created from `s`. This
* produces hash corresponding to the one signed with the
* https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
* JSON-RPC method as part of EIP-191.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(s.length), s));
}
/**
* @dev Returns an Ethereum Signed Typed Data, created from a
* `domainSeparator` and a `structHash`. This produces hash corresponding
* to the one signed with the
* https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
* JSON-RPC method as part of EIP-712.
*
* See {recover}.
*/
function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
return keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
}
}
