Contract Source Code:
// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.4;
import './ERC721B.sol';
import '@openzeppelin/contracts/access/Ownable.sol';
import '@openzeppelin/contracts/utils/cryptography/MerkleProof.sol';
import '@openzeppelin/contracts/utils/Strings.sol';
error InvalidProof();
error OverMaxSupply();
error WrongEtherValue();
error OverMintLimit();
error DoubleClaim();
error SaleNotActive();
contract Unmasked is ERC721B, Ownable {
using Strings for uint256;
// OpenSea whitelisting
address constant proxyRegistryAddress = address(0xa5409ec958C83C3f309868babACA7c86DCB077c1);
mapping(address => bool) public addressToRegistryDisabled;
// Merkle whitelisting
mapping(address => bool) public claimed;
bytes32 public CLAIM_ROOT;
bytes32 public WHITELIST_ROOT;
// collection specific parameters
string private baseURI;
string public provenance;
bool public publicSaleActive;
uint256 public supply = 3333;
uint256 public price = 0.06 ether;
uint256 public price2 = 0.04 ether;
uint256 constant maxBatchSize = 20;
constructor() ERC721B('TheUnmasked', 'UNMASKED') {}
/*///////////////////////////////////////////////////////////////
OWNER FUNCTIONS
//////////////////////////////////////////////////////////////*/
function withdraw() external onlyOwner {
uint256 balance = address(this).balance;
payable(msg.sender).transfer(balance);
}
function setClaim(bytes32 _root) external onlyOwner {
CLAIM_ROOT = _root;
}
function setWhitelist(bytes32 _root) external onlyOwner {
WHITELIST_ROOT = _root;
}
function setProvenanceHash(string calldata provenanceHash) external onlyOwner {
provenance = provenanceHash;
}
function setBaseURI(string calldata _baseURI) external onlyOwner {
baseURI = _baseURI;
}
function togglePublicSale() external onlyOwner {
publicSaleActive = !publicSaleActive;
}
function setPrice(uint256 _price, uint256 _price2) external onlyOwner {
price = _price;
price2 = _price2;
}
function setSupply(uint256 _supply) external onlyOwner {
supply = _supply;
}
/**
* Reserve NFTs for giveaways
*/
function reserveUnmasked(uint256 qty) external onlyOwner {
if ((_owners.length + qty) > supply) revert OverMaxSupply();
_mint(msg.sender, qty);
}
/**
* Claim function for whitelisted addresses
*/
function claim(
address account,
uint256 qty,
bytes32[] calldata proof
) external {
if (!_verify(_leaf(account, qty), proof)) revert InvalidProof();
if ((_owners.length + qty) > supply) revert OverMaxSupply();
if (claimed[account]) revert DoubleClaim();
// set claimed to true to prevent double claiming
claimed[account] = true;
_mint(account, qty);
}
function whitelistMint(uint256 qty, bytes32[] calldata proof) external payable {
if (!_verify2(_leaf2(msg.sender), proof)) revert InvalidProof();
if (qty > maxBatchSize) revert OverMintLimit();
if ((_owners.length + qty) > supply) revert OverMaxSupply();
if (msg.value < price2 * qty) revert WrongEtherValue();
_mint(msg.sender, qty);
}
function publicMint(uint256 qty) external payable {
if (!publicSaleActive) revert SaleNotActive();
if (qty > maxBatchSize) revert OverMintLimit();
if ((_owners.length + qty) > supply) revert OverMaxSupply();
if (msg.value < price * qty) revert WrongEtherValue();
_safeMint(msg.sender, qty);
}
/**
An override to whitelist the OpenSea proxy contract to enable gas-free
listings. This function returns true if `_operator` is approved to transfer
items owned by `_owner`.
@param owner The owner of items to check for transfer ability.
@param operator The potential transferrer of `_owner`'s items.
*/
function isApprovedForAll(address owner, address operator) public view override returns (bool) {
// Whitelist OpenSea proxy contract for easy trading.
ProxyRegistry proxyRegistry = ProxyRegistry(proxyRegistryAddress);
if (address(proxyRegistry.proxies(owner)) == operator && !addressToRegistryDisabled[owner]) {
return true;
}
return super.isApprovedForAll(owner, operator);
}
/**
* @notice Allow a user to disable the OpenSea pre-approval if they believe OS to not be secure.
*/
function toggleRegistryAccess() public virtual {
addressToRegistryDisabled[msg.sender] = !addressToRegistryDisabled[msg.sender];
}
/**
* @dev See {IERC721Metadata-tokenURI}.
*/
function tokenURI(uint256 _tokenId) public view override returns (string memory) {
if (!_exists(_tokenId)) revert URIQueryForNonexistentToken();
return string(abi.encodePacked(baseURI, Strings.toString(_tokenId)));
}
/**
* @dev See OpenZeppelin MerkleProof.
*/
function _leaf(address account, uint256 qty) internal pure returns (bytes32) {
return keccak256(abi.encodePacked(account, qty));
}
function _leaf2(address account) internal pure returns (bytes32) {
return keccak256(abi.encodePacked(account));
}
function _verify(bytes32 leaf, bytes32[] memory proof) internal view returns (bool) {
return MerkleProof.verify(proof, CLAIM_ROOT, leaf);
}
function _verify2(bytes32 leaf, bytes32[] memory proof) internal view returns (bool) {
return MerkleProof.verify(proof, WHITELIST_ROOT, leaf);
}
}
/**
@title An OpenSea delegate proxy contract which we include for whitelisting.
@author OpenSea
*/
contract OwnableDelegateProxy {
}
/**
* Used to delegate ownership of a contract to another address,
* to save on unneeded transactions to approve contract use for users
*/
contract ProxyRegistry {
mapping(address => OwnableDelegateProxy) public proxies;
}
// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.4;
import '@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol';
error ApprovalCallerNotOwnerNorApproved();
error ApprovalQueryForNonexistentToken();
error ApproveToCaller();
error ApprovalToCurrentOwner();
error BalanceQueryForZeroAddress();
error MintedQueryForZeroAddress();
error MintToZeroAddress();
error MintZeroQuantity();
error OwnerIndexOutOfBounds();
error OwnerQueryForNonexistentToken();
error TokenIndexOutOfBounds();
error TransferCallerNotOwnerNorApproved();
error TransferFromIncorrectOwner();
error TransferToNonERC721ReceiverImplementer();
error TransferToZeroAddress();
error UnableDetermineTokenOwner();
error UnableGetTokenOwnerByIndex();
error URIQueryForNonexistentToken();
/**
* Updated, minimalist and gas efficient version of OpenZeppelins ERC721 contract.
* Includes the Metadata and Enumerable extension.
*
* Assumes serials are sequentially minted starting at 0 (e.g. 0, 1, 2, 3..).
* Does not support burning tokens
*
* @author beskay0x
* Credits: chiru-labs, solmate, transmissions11, nftchance, squeebo_nft and others
*/
abstract contract ERC721B {
/*///////////////////////////////////////////////////////////////
EVENTS
//////////////////////////////////////////////////////////////*/
event Transfer(address indexed from, address indexed to, uint256 indexed id);
event Approval(address indexed owner, address indexed spender, uint256 indexed id);
event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
/*///////////////////////////////////////////////////////////////
METADATA STORAGE/LOGIC
//////////////////////////////////////////////////////////////*/
string public name;
string public symbol;
function tokenURI(uint256 tokenId) public view virtual returns (string memory);
/*///////////////////////////////////////////////////////////////
ERC721 STORAGE
//////////////////////////////////////////////////////////////*/
// Array which maps token ID to address (index is tokenID)
address[] internal _owners;
// 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
//////////////////////////////////////////////////////////////*/
constructor(string memory _name, string memory _symbol) {
name = _name;
symbol = _symbol;
}
/*///////////////////////////////////////////////////////////////
ERC165 LOGIC
//////////////////////////////////////////////////////////////*/
function supportsInterface(bytes4 interfaceId) public view virtual returns (bool) {
return
interfaceId == 0x01ffc9a7 || // ERC165 Interface ID for ERC165
interfaceId == 0x80ac58cd || // ERC165 Interface ID for ERC721
interfaceId == 0x780e9d63 || // ERC165 Interface ID for ERC721Enumerable
interfaceId == 0x5b5e139f; // ERC165 Interface ID for ERC721Metadata
}
/*///////////////////////////////////////////////////////////////
ERC721ENUMERABLE LOGIC
//////////////////////////////////////////////////////////////*/
/**
* @dev See {IERC721Enumerable-totalSupply}.
*/
function totalSupply() public view returns (uint256) {
return _owners.length;
}
/**
* @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
* Dont call this function on chain from another smart contract, since it can become quite expensive
*/
function tokenOfOwnerByIndex(address owner, uint256 index) public view virtual returns (uint256 tokenId) {
if (index >= balanceOf(owner)) revert OwnerIndexOutOfBounds();
uint256 count;
uint256 qty = _owners.length;
// Cannot realistically overflow, since we are using uint256
unchecked {
for (tokenId; tokenId < qty; tokenId++) {
if (owner == ownerOf(tokenId)) {
if (count == index) return tokenId;
else count++;
}
}
}
revert UnableGetTokenOwnerByIndex();
}
/**
* @dev See {IERC721Enumerable-tokenByIndex}.
*/
function tokenByIndex(uint256 index) public view virtual returns (uint256) {
if (index >= totalSupply()) revert TokenIndexOutOfBounds();
return index;
}
/*///////////////////////////////////////////////////////////////
ERC721 LOGIC
//////////////////////////////////////////////////////////////*/
/**
* @dev Iterates through _owners array, returns balance of address
* It is not recommended to call this function from another smart contract
* as it can become quite expensive -- call this function off chain instead.
*/
function balanceOf(address owner) public view virtual returns (uint256) {
if (owner == address(0)) revert BalanceQueryForZeroAddress();
uint256 count;
uint256 qty = _owners.length;
// Cannot realistically overflow, since we are using uint256
unchecked {
for (uint256 i; i < qty; i++) {
if (owner == ownerOf(i)) {
count++;
}
}
}
return count;
}
/**
* @dev See {IERC721-ownerOf}.
* 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 ownerOf(uint256 tokenId) public view virtual returns (address) {
if (!_exists(tokenId)) revert OwnerQueryForNonexistentToken();
// Cannot realistically overflow, since we are using uint256
unchecked {
for (tokenId; ; tokenId++) {
if (_owners[tokenId] != address(0)) {
return _owners[tokenId];
}
}
}
revert UnableDetermineTokenOwner();
}
/**
* @dev See {IERC721-approve}.
*/
function approve(address to, uint256 tokenId) public virtual {
address owner = ownerOf(tokenId);
if (to == owner) revert ApprovalToCurrentOwner();
if (msg.sender != owner && !isApprovedForAll(owner, msg.sender)) revert ApprovalCallerNotOwnerNorApproved();
_tokenApprovals[tokenId] = to;
emit Approval(owner, to, tokenId);
}
/**
* @dev See {IERC721-getApproved}.
*/
function getApproved(uint256 tokenId) public view virtual returns (address) {
if (!_exists(tokenId)) revert ApprovalQueryForNonexistentToken();
return _tokenApprovals[tokenId];
}
/**
* @dev See {IERC721-setApprovalForAll}.
*/
function setApprovalForAll(address operator, bool approved) public virtual {
if (operator == msg.sender) revert ApproveToCaller();
_operatorApprovals[msg.sender][operator] = approved;
emit ApprovalForAll(msg.sender, operator, approved);
}
/**
* @dev See {IERC721-isApprovedForAll}.
*/
function isApprovedForAll(address owner, address operator) public view virtual returns (bool) {
return _operatorApprovals[owner][operator];
}
/**
* @dev See {IERC721-transferFrom}.
*/
function transferFrom(
address from,
address to,
uint256 tokenId
) public virtual {
if (!_exists(tokenId)) revert OwnerQueryForNonexistentToken();
if (ownerOf(tokenId) != from) revert TransferFromIncorrectOwner();
if (to == address(0)) revert TransferToZeroAddress();
bool isApprovedOrOwner = (msg.sender == from ||
msg.sender == getApproved(tokenId) ||
isApprovedForAll(from, msg.sender));
if (!isApprovedOrOwner) revert TransferCallerNotOwnerNorApproved();
// delete token approvals from previous owner
delete _tokenApprovals[tokenId];
_owners[tokenId] = to;
// if token ID below transferred one isnt set, set it to previous owner
// if tokenid is zero, skip this to prevent underflow
if (tokenId > 0 && _owners[tokenId - 1] == address(0)) {
_owners[tokenId - 1] = from;
}
emit Transfer(from, to, tokenId);
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/
function safeTransferFrom(
address from,
address to,
uint256 id
) public virtual {
safeTransferFrom(from, to, id, '');
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/
function safeTransferFrom(
address from,
address to,
uint256 id,
bytes memory data
) public virtual {
transferFrom(from, to, id);
if (!_checkOnERC721Received(from, to, id, data)) revert TransferToNonERC721ReceiverImplementer();
}
/**
* @dev Returns whether `tokenId` exists.
*/
function _exists(uint256 tokenId) internal view virtual returns (bool) {
return tokenId < _owners.length;
}
/**
* @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.code.length == 0) return true;
try IERC721Receiver(to).onERC721Received(msg.sender, from, tokenId, _data) returns (bytes4 retval) {
return retval == IERC721Receiver(to).onERC721Received.selector;
} catch (bytes memory reason) {
if (reason.length == 0) revert TransferToNonERC721ReceiverImplementer();
assembly {
revert(add(32, reason), mload(reason))
}
}
}
/*///////////////////////////////////////////////////////////////
INTERNAL MINT LOGIC
//////////////////////////////////////////////////////////////*/
/**
* @dev check if contract confirms token transfer, if not - reverts
* unlike the standard ERC721 implementation this is only called once per mint,
* no matter how many tokens get minted, since it is useless to check this
* requirement several times -- if the contract confirms one token,
* it will confirm all additional ones too.
* This saves us around 5k gas per additional mint
*/
function _safeMint(address to, uint256 qty) internal virtual {
_safeMint(to, qty, '');
}
function _safeMint(
address to,
uint256 qty,
bytes memory data
) internal virtual {
_mint(to, qty);
if (!_checkOnERC721Received(address(0), to, _owners.length - 1, data))
revert TransferToNonERC721ReceiverImplementer();
}
function _mint(address to, uint256 qty) internal virtual {
if (to == address(0)) revert MintToZeroAddress();
if (qty == 0) revert MintZeroQuantity();
uint256 _currentIndex = _owners.length;
// Cannot realistically overflow, since we are using uint256
unchecked {
for (uint256 i; i < qty - 1; i++) {
_owners.push();
emit Transfer(address(0), to, _currentIndex + i);
}
}
// set last index to receiver
_owners.push(to);
emit Transfer(address(0), to, _currentIndex + (qty - 1));
}
}
// 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 (last updated v4.5.0) (utils/cryptography/MerkleProof.sol)
pragma solidity ^0.8.0;
/**
* @dev These functions deal with verification of Merkle Trees proofs.
*
* The proofs can be generated using the JavaScript library
* https://github.com/miguelmota/merkletreejs[merkletreejs].
* Note: the hashing algorithm should be keccak256 and pair sorting should be enabled.
*
* See `test/utils/cryptography/MerkleProof.test.js` for some examples.
*/
library MerkleProof {
/**
* @dev Returns true if a `leaf` can be proved to be a part of a Merkle tree
* defined by `root`. For this, a `proof` must be provided, containing
* sibling hashes on the branch from the leaf to the root of the tree. Each
* pair of leaves and each pair of pre-images are assumed to be sorted.
*/
function verify(
bytes32[] memory proof,
bytes32 root,
bytes32 leaf
) internal pure returns (bool) {
return processProof(proof, leaf) == root;
}
/**
* @dev Returns the rebuilt hash obtained by traversing a Merklee tree up
* from `leaf` using `proof`. A `proof` is valid if and only if the rebuilt
* hash matches the root of the tree. When processing the proof, the pairs
* of leafs & pre-images are assumed to be sorted.
*
* _Available since v4.4._
*/
function processProof(bytes32[] memory proof, bytes32 leaf) internal pure returns (bytes32) {
bytes32 computedHash = leaf;
for (uint256 i = 0; i < proof.length; i++) {
bytes32 proofElement = proof[i];
if (computedHash <= proofElement) {
// Hash(current computed hash + current element of the proof)
computedHash = _efficientHash(computedHash, proofElement);
} else {
// Hash(current element of the proof + current computed hash)
computedHash = _efficientHash(proofElement, computedHash);
}
}
return computedHash;
}
function _efficientHash(bytes32 a, bytes32 b) private pure returns (bytes32 value) {
assembly {
mstore(0x00, a)
mstore(0x20, b)
value := keccak256(0x00, 0x40)
}
}
}
// 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 (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 `IERC721.onERC721Received.selector`.
*/
function onERC721Received(
address operator,
address from,
uint256 tokenId,
bytes calldata data
) external returns (bytes4);
}
// 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;
}
}