// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;/**
* @dev Collection of functions related to the address type
*/libraryAddress{
/**
* @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
* ====
*/functionisContract(address account) internalviewreturns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in// construction, since the code is only stored at the end of the// constructor execution.uint256 size;
assembly {
size :=extcodesize(account)
}
return size >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].
*/functionsendValue(addresspayable 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._
*/functionfunctionCall(address target, bytesmemory data) internalreturns (bytesmemory) {
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._
*/functionfunctionCall(address target,
bytesmemory data,
stringmemory errorMessage
) internalreturns (bytesmemory) {
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._
*/functionfunctionCallWithValue(address target,
bytesmemory data,
uint256 value
) internalreturns (bytesmemory) {
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._
*/functionfunctionCallWithValue(address target,
bytesmemory data,
uint256 value,
stringmemory errorMessage
) internalreturns (bytesmemory) {
require(address(this).balance>= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
(bool success, bytesmemory 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._
*/functionfunctionStaticCall(address target, bytesmemory data) internalviewreturns (bytesmemory) {
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._
*/functionfunctionStaticCall(address target,
bytesmemory data,
stringmemory errorMessage
) internalviewreturns (bytesmemory) {
require(isContract(target), "Address: static call to non-contract");
(bool success, bytesmemory 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._
*/functionfunctionDelegateCall(address target, bytesmemory data) internalreturns (bytesmemory) {
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._
*/functionfunctionDelegateCall(address target,
bytesmemory data,
stringmemory errorMessage
) internalreturns (bytesmemory) {
require(isContract(target), "Address: delegate call to non-contract");
(bool success, bytesmemory 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._
*/functionverifyCallResult(bool success,
bytesmemory returndata,
stringmemory errorMessage
) internalpurereturns (bytesmemory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if presentif (returndata.length>0) {
// The easiest way to bubble the revert reason is using memory via assemblyassembly {
let returndata_size :=mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
Contract Source Code
File 2 of 15: BlankArt.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.4;import"@openzeppelin/contracts/access/Ownable.sol";
import"@openzeppelin/contracts/token/ERC721/ERC721.sol";
import"@openzeppelin/contracts/token/ERC721/extensions/ERC721URIStorage.sol";
import"@openzeppelin/contracts/utils/cryptography/ECDSA.sol";
import"@openzeppelin/contracts/utils/cryptography/draft-EIP712.sol";
import"./IERC2981.sol";
contractBlankArtisERC721, EIP712, ERC721URIStorage, Ownable, IERC2981{
eventInitialized(address controller,
address signer,
string baseURI,
uint256 mintPrice,
uint256 maxTokenSupply,
bool active,
bool publicMint
);
// An event whenever the foundation address is updatedeventFoundationAddressUpdated(address foundationAddress);
// An event whenever the voucher signer address is updatedeventVoucherSignersUpdated(address foundationAddress, bool active);
eventBaseTokenUriUpdated(string baseTokenURI);
eventPermanentURI(string _value, uint256indexed _id); // https://docs.opensea.io/docs/metadata-standardseventMinted(uint256 tokenId, address member, string tokenURI);
eventBlankRoyaltySet(address recipient, uint16 bps);
// if a token's URI has been locked or notmapping(uint256=>uint256) public tokenURILocked;
// signing domainstringprivateconstant SIGNING_DOMAIN ="BlankNFT";
// signature versionstringprivateconstant SIGNATURE_VERSION ="1";
// address which signs the vouchermapping(address=>bool) _voucherSigners;
// Array of _baseURIsstring[] private _baseURIs;
// gets incremented to placehold for tokens not minted yetuint256public maxTokenSupply;
// cost to mint during the public saleuint256public mintPrice;
// Enables/Disables voucher redemptionboolpublic active;
// Enables/Disables public minting (without a whitelisted voucher)boolpublic publicMint;
// the address of the platform (for receiving commissions and royalties)addresspayablepublic foundationAddress;
// pending withdrawals by account addressmapping(address=>uint256) pendingWithdrawals;
// Max number of tokens a member can mintuint8public memberMaxMintCount;
// current token indexuint256public tokenIndex;
// pending withdrawals by account addressmapping(bytes32=>bool) private voucherClaimed;
// EIP2981structRoyaltyInfo {
address recipient;
uint24 bps;
}
RoyaltyInfo public blankRoyalty;
constructor(addresspayable _foundationAddress,
address _signer,
uint256 _maxTokenSupply,
stringmemory baseURI,
uint16 _royaltyBPS
) ERC721("BlankArt", "BLANK") EIP712(SIGNING_DOMAIN, SIGNATURE_VERSION) {
memberMaxMintCount =5;
foundationAddress = _foundationAddress;
_voucherSigners[_signer] =true;
maxTokenSupply = _maxTokenSupply;
require(maxTokenSupply >0);
tokenIndex =1;
mintPrice =0;
publicMint =false;
_baseURIs.push("");
// Default the initial index to 1. The lockTokenURI map will default to 0 for all unmapped tokens.
_baseURIs.push(baseURI);
active =true;
emit Initialized(
foundationAddress,
_signer,
baseURI,
mintPrice,
maxTokenSupply,
active,
publicMint
);
//Setup the initial royalty recipient and amount
blankRoyalty = RoyaltyInfo(_foundationAddress, _royaltyBPS);
}
/// @notice Represents a voucher to claim any un-minted NFT (up to memberMaxMintCount), which has not yet been recorded into the blockchain. A signed voucher can be redeemed for real NFTs using the redeemVoucher function.structBlankNFTVoucher {
/// @notice address of intended redeemeraddress redeemerAddress;
/// @notice Expiration of the voucher, expressed in seconds since the Unix epoch.uint256 expiration;
/// @notice The minimum price (in wei) that the NFT creator is willing to accept for the initial sale of this NFT.uint256 minPrice;
/// @notice amount of tokens the voucher can claim.uint16 tokenCount;
/// @notice the EIP-712 signature of all other fields in the NFTVoucher struct. For a voucher to be valid, it must be signed by an account with the MINTER_ROLE.bytes signature;
}
function_beforeTokenTransfer(addressfrom,
address to,
uint256 tokenId
) internaloverride(ERC721) {
super._beforeTokenTransfer(from, to, tokenId);
}
function_burn(uint256 tokenId) internaloverride(ERC721, ERC721URIStorage) {
super._burn(tokenId);
}
functionisMember(address account) externalviewreturns (bool) {
return (balanceOf(account) >0);
}
functionaddBaseURI(stringcalldata baseURI) externalonlyOwner{
_baseURIs.push(baseURI);
emit BaseTokenUriUpdated(baseURI);
}
// Overridden. Gets the TokenURI based on the locked version.functiontokenURI(uint256 tokenId)
publicviewoverride(ERC721, ERC721URIStorage)
returns (stringmemory)
{
stringmemory _base ="";
require(_exists(tokenId), "ERC721URIStorage: URI query for nonexistent token");
if (tokenURILocked[tokenId] >0) _base = _baseURIs[tokenURILocked[tokenId]];
else _base = _baseURIs[_baseURIs.length-1];
returnstring(abi.encodePacked(_base, Strings.toString(tokenId), ".json"));
}
function_checkMemberMintCount(address account) internalview{
if (balanceOf(account) >= memberMaxMintCount) {
revert(
string(
abi.encodePacked(
"Account ",
Strings.toHexString(uint160(account), 20),
" has reached its minting limit of ",
memberMaxMintCount,
", so cannot mint"
)
)
);
}
}
// Allows the current foundation address to update to something differentfunctionupdateFoundationAddress(addresspayable newFoundationAddress) externalonlyOwner{
foundationAddress = newFoundationAddress;
emit FoundationAddressUpdated(newFoundationAddress);
}
// Allows the voucher signing addressfunctionaddVoucherSigner(address newVoucherSigner) externalonlyOwner{
_voucherSigners[newVoucherSigner] =true;
emit VoucherSignersUpdated(newVoucherSigner, true);
}
// Disallows a voucher signing addressfunctionremoveVoucherSigner(address oldVoucherSigner) externalonlyOwner{
_voucherSigners[oldVoucherSigner] =false;
emit VoucherSignersUpdated(oldVoucherSigner, false);
}
// Locks a token's URI from being updated. Only callable by the token owner.functionlockTokenURI(uint256 tokenId) external{
// ensure that this token existsrequire(_exists(tokenId), "ERC721URIStorage: URI query for nonexistent token");
// ensure that the token is owned by the callerrequire(ownerOf(tokenId) ==msg.sender, "Invalid: Only the owner can lock their token");
// lock this token's URI from being changed
tokenURILocked[tokenId] = _baseURIs.length-1;
emit PermanentURI(tokenURI(tokenId), tokenId);
}
// Updates the mintPricefunctionupdateMintPrice(uint256 price) externalonlyOwner{
// Update the mintPrice
mintPrice = price;
}
// Updates the memberMaxMintCountfunctionupdateMaxMintCount(uint8 _maxMint) externalonlyOwner{
require(_maxMint >0, "Max mint cannot be zero");
memberMaxMintCount = _maxMint;
}
// Toggle the value of publicMintfunctiontogglePublicMint() externalonlyOwner{
publicMint =!publicMint;
}
// Pause mintingfunctiontoggleActivation() externalonlyOwner{
active =!active;
}
function_mintBlank(address owner) privatereturns (uint256) {
uint256 tokenId = tokenIndex;
_checkMemberMintCount(owner);
super._safeMint(owner, tokenId);
tokenIndex++;
stringmemory tokenUri = tokenURI(tokenId);
emit Minted(tokenId, owner, tokenUri);
return tokenId;
}
functionredeemVoucher(uint256 amount, BlankNFTVoucher calldata voucher)
publicpayablereturns (uint256[] memory)
{
// make sure voucher redemption period is activerequire(active, "Voucher redemption is not currently active");
// make sure signature is valid and get the address of the signeraddress signer = _verify(voucher);
// make sure caller is the redeemerrequire(msg.sender== voucher.redeemerAddress, "Voucher is for a different wallet address");
// make sure voucher has not expired.require(block.timestamp<= voucher.expiration, "Voucher has expired");
// make sure that the signer is the designated signerrequire(_voucherSigners[signer], "Signature invalid or unauthorized");
require(
balanceOf(voucher.redeemerAddress) + amount <= memberMaxMintCount,
"Amount is more than the minting limit"
);
require(tokenIndex + amount <= maxTokenSupply +1, "All tokens have already been minted");
// make sure that the redeemer is paying enough to cover the buyer's costrequire(msg.value>= (voucher.minPrice * amount), "Insufficient funds to redeem");
require(amount <= voucher.tokenCount, "Amount is more than the voucher allows");
// make sure voucher has not already been claimed. If true, it HAS been claimedrequire(!voucherClaimed[_hash(voucher)], "Voucher has already been claimed");
// assign the token directly to the redeemeruint256[] memory tokenIds =newuint256[](amount);
for (uint256 num =0; num < amount; num++) {
uint256 tokenId = _mintBlank(voucher.redeemerAddress);
tokenIds[num] = tokenId;
}
// record payment to signer's withdrawal balance
pendingWithdrawals[foundationAddress] +=msg.value;
voucherClaimed[_hash(voucher)] =true;
return tokenIds;
}
// Public mint function. Whitelisted members will utilize redeemVoucher()functionmint(uint256 amount) publicpayablereturns (uint256[] memory) {
require(publicMint && active, "Public minting is not active.");
require(
balanceOf(msg.sender) + amount <= memberMaxMintCount,
"Amount is more than the minting limit"
);
require(tokenIndex + amount <= maxTokenSupply +1, "All tokens have already been minted");
// make sure that the caller is paying enough to cover the mintPricerequire(msg.value>= (mintPrice * amount), "Insufficient funds to mint");
// assign the token directly to the redeemeruint256[] memory tokenIds =newuint256[](amount);
for (uint256 num =0; num < amount; num++) {
uint256 tokenId = _mintBlank(msg.sender);
tokenIds[num] = tokenId;
}
// record payment to foundationAddress withdrawal balance
pendingWithdrawals[foundationAddress] +=msg.value;
return tokenIds;
}
/// @notice Transfers all pending withdrawal balance to the caller. Reverts if the caller is not an authorized minter.functionwithdraw() public{
// IMPORTANT: casting msg.sender to a payable address is only safe if ALL members of the minter role are payable addresses.addresspayable receiver =payable(msg.sender);
uint256 amount = pendingWithdrawals[receiver];
// zero account before transfer to prevent re-entrancy attack
pendingWithdrawals[receiver] =0;
receiver.transfer(amount);
}
/// @notice Returns the amount of Ether available to the caller to withdraw.functionavailableToWithdraw() publicviewreturns (uint256) {
return pendingWithdrawals[msg.sender];
}
/// @notice Returns a hash of the given BlankNFTVoucher, prepared using EIP712 typed data hashing rules./// @param voucher An NFTVoucher to hash.function_hash(BlankNFTVoucher calldata voucher) internalviewreturns (bytes32) {
return
_hashTypedDataV4(
keccak256(
abi.encode(
keccak256(
"BlankNFTVoucher(address redeemerAddress,uint256 expiration,uint256 minPrice,uint16 tokenCount)"
),
voucher.redeemerAddress,
voucher.expiration,
voucher.minPrice,
voucher.tokenCount
)
)
);
}
/// @notice Returns the chain id of the current blockchain./// @dev This is used to workaround an issue with ganache returning different values from the on-chain chainid() function and/// the eth_chainId RPC method. See https://github.com/protocol/nft-website/issues/121 for context.functiongetChainID() externalviewreturns (uint256) {
uint256 id;
assembly {
id :=chainid()
}
return id;
}
/// @notice Verifies the signature for a given BlankNFTVoucher, returning the address of the signer./// @dev Will revert if the signature is invalid. Does not verify that the signer is authorized to mint NFTs./// @param voucher An BlankNFTVoucher describing an unminted NFT.function_verify(BlankNFTVoucher calldata voucher) internalviewreturns (address) {
bytes32 digest = _hash(voucher);
return ECDSA.recover(digest, voucher.signature);
}
/// @notice Called with the sale price to determine how much royalty// is owed and to whom./// @param - the tokenId queried for royalty information --Not Utilized, All tokens have the same royalty/// @param salePrice - the sale price of the NFT asset specified by _tokenId/// @return receiver - address of who should be sent the royalty payment/// @return royaltyAmount - the royalty payment amount for _salePricefunctionroyaltyInfo(uint256, uint256 salePrice)
externalviewoverride(IERC2981)
returns (address receiver, uint256 royaltyAmount)
{
return (
blankRoyalty.recipient,
(salePrice * blankRoyalty.bps) /10000
);
}
/// @dev Update the address which receives royalties, and the fee charged/// @param recipient address of who should be sent the royalty payment/// @param bps uint256 amount of fee (1% == 100)functionsetDefaultRoyalty(address recipient, uint16 bps)
publiconlyOwner{
blankRoyalty = RoyaltyInfo(recipient, bps);
emit BlankRoyaltySet(recipient, bps);
}
functionsupportsInterface(bytes4 interfaceId)
publicviewvirtualoverride(ERC721, IERC165)
returns (bool)
{
return ERC721.supportsInterface(interfaceId) || interfaceId ==type(IERC2981).interfaceId;
}
}
Contract Source Code
File 3 of 15: Context.sol
// SPDX-License-Identifier: MITpragmasolidity ^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.
*/abstractcontractContext{
function_msgSender() internalviewvirtualreturns (address) {
returnmsg.sender;
}
function_msgData() internalviewvirtualreturns (bytescalldata) {
returnmsg.data;
}
}
Contract Source Code
File 4 of 15: ECDSA.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;/**
* @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.
*/libraryECDSA{
enumRecoverError {
NoError,
InvalidSignature,
InvalidSignatureLength,
InvalidSignatureS,
InvalidSignatureV
}
function_throwError(RecoverError error) privatepure{
if (error == RecoverError.NoError) {
return; // no error: do nothing
} elseif (error == RecoverError.InvalidSignature) {
revert("ECDSA: invalid signature");
} elseif (error == RecoverError.InvalidSignatureLength) {
revert("ECDSA: invalid signature length");
} elseif (error == RecoverError.InvalidSignatureS) {
revert("ECDSA: invalid signature 's' value");
} elseif (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._
*/functiontryRecover(bytes32 hash, bytesmemory signature) internalpurereturns (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);
} elseif (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.
*/functionrecover(bytes32 hash, bytesmemory signature) internalpurereturns (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._
*/functiontryRecover(bytes32 hash,
bytes32 r,
bytes32 vs
) internalpurereturns (address, RecoverError) {
bytes32 s;
uint8 v;
assembly {
s :=and(vs, 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
v :=add(shr(255, vs), 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._
*/functionrecover(bytes32 hash,
bytes32 r,
bytes32 vs
) internalpurereturns (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._
*/functiontryRecover(bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internalpurereturns (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 addressaddress 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.
*/functionrecover(bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internalpurereturns (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}.
*/functiontoEthSignedMessageHash(bytes32 hash) internalpurereturns (bytes32) {
// 32 is the length in bytes of hash,// enforced by the type signature abovereturnkeccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
}
/**
* @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}.
*/functiontoTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internalpurereturns (bytes32) {
returnkeccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
}
}
Contract Source Code
File 5 of 15: ERC165.sol
// SPDX-License-Identifier: MITpragmasolidity ^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.
*/abstractcontractERC165isIERC165{
/**
* @dev See {IERC165-supportsInterface}.
*/functionsupportsInterface(bytes4 interfaceId) publicviewvirtualoverridereturns (bool) {
return interfaceId ==type(IERC165).interfaceId;
}
}
Contract Source Code
File 6 of 15: ERC721.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;import"./IERC721.sol";
import"./IERC721Receiver.sol";
import"./extensions/IERC721Metadata.sol";
import"../../utils/Address.sol";
import"../../utils/Context.sol";
import"../../utils/Strings.sol";
import"../../utils/introspection/ERC165.sol";
/**
* @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
* the Metadata extension, but not including the Enumerable extension, which is available separately as
* {ERC721Enumerable}.
*/contractERC721isContext, ERC165, IERC721, IERC721Metadata{
usingAddressforaddress;
usingStringsforuint256;
// Token namestringprivate _name;
// Token symbolstringprivate _symbol;
// Mapping from token ID to owner addressmapping(uint256=>address) private _owners;
// Mapping owner address to token countmapping(address=>uint256) private _balances;
// Mapping from token ID to approved addressmapping(uint256=>address) private _tokenApprovals;
// Mapping from owner to operator approvalsmapping(address=>mapping(address=>bool)) private _operatorApprovals;
/**
* @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
*/constructor(stringmemory name_, stringmemory symbol_) {
_name = name_;
_symbol = symbol_;
}
/**
* @dev See {IERC165-supportsInterface}.
*/functionsupportsInterface(bytes4 interfaceId) publicviewvirtualoverride(ERC165, IERC165) returns (bool) {
return
interfaceId ==type(IERC721).interfaceId||
interfaceId ==type(IERC721Metadata).interfaceId||super.supportsInterface(interfaceId);
}
/**
* @dev See {IERC721-balanceOf}.
*/functionbalanceOf(address owner) publicviewvirtualoverridereturns (uint256) {
require(owner !=address(0), "ERC721: balance query for the zero address");
return _balances[owner];
}
/**
* @dev See {IERC721-ownerOf}.
*/functionownerOf(uint256 tokenId) publicviewvirtualoverridereturns (address) {
address owner = _owners[tokenId];
require(owner !=address(0), "ERC721: owner query for nonexistent token");
return owner;
}
/**
* @dev See {IERC721Metadata-name}.
*/functionname() publicviewvirtualoverridereturns (stringmemory) {
return _name;
}
/**
* @dev See {IERC721Metadata-symbol}.
*/functionsymbol() publicviewvirtualoverridereturns (stringmemory) {
return _symbol;
}
/**
* @dev See {IERC721Metadata-tokenURI}.
*/functiontokenURI(uint256 tokenId) publicviewvirtualoverridereturns (stringmemory) {
require(_exists(tokenId), "ERC721Metadata: URI query for nonexistent token");
stringmemory baseURI = _baseURI();
returnbytes(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() internalviewvirtualreturns (stringmemory) {
return"";
}
/**
* @dev See {IERC721-approve}.
*/functionapprove(address to, uint256 tokenId) publicvirtualoverride{
address owner = ERC721.ownerOf(tokenId);
require(to != owner, "ERC721: approval to current owner");
require(
_msgSender() == owner || isApprovedForAll(owner, _msgSender()),
"ERC721: approve caller is not owner nor approved for all"
);
_approve(to, tokenId);
}
/**
* @dev See {IERC721-getApproved}.
*/functiongetApproved(uint256 tokenId) publicviewvirtualoverridereturns (address) {
require(_exists(tokenId), "ERC721: approved query for nonexistent token");
return _tokenApprovals[tokenId];
}
/**
* @dev See {IERC721-setApprovalForAll}.
*/functionsetApprovalForAll(address operator, bool approved) publicvirtualoverride{
require(operator != _msgSender(), "ERC721: approve to caller");
_operatorApprovals[_msgSender()][operator] = approved;
emit ApprovalForAll(_msgSender(), operator, approved);
}
/**
* @dev See {IERC721-isApprovedForAll}.
*/functionisApprovedForAll(address owner, address operator) publicviewvirtualoverridereturns (bool) {
return _operatorApprovals[owner][operator];
}
/**
* @dev See {IERC721-transferFrom}.
*/functiontransferFrom(addressfrom,
address to,
uint256 tokenId
) publicvirtualoverride{
//solhint-disable-next-line max-line-lengthrequire(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
_transfer(from, to, tokenId);
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/functionsafeTransferFrom(addressfrom,
address to,
uint256 tokenId
) publicvirtualoverride{
safeTransferFrom(from, to, tokenId, "");
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/functionsafeTransferFrom(addressfrom,
address to,
uint256 tokenId,
bytesmemory _data
) publicvirtualoverride{
require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: transfer caller is not owner nor approved");
_safeTransfer(from, to, tokenId, _data);
}
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
* are aware of the ERC721 protocol to prevent tokens from being forever locked.
*
* `_data` is additional data, it has no specified format and it is sent in call to `to`.
*
* This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
* implement alternative mechanisms to perform token transfer, such as signature-based.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/function_safeTransfer(addressfrom,
address to,
uint256 tokenId,
bytesmemory _data
) internalvirtual{
_transfer(from, to, tokenId);
require(_checkOnERC721Received(from, to, tokenId, _data), "ERC721: transfer to non ERC721Receiver implementer");
}
/**
* @dev Returns whether `tokenId` exists.
*
* Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
*
* Tokens start existing when they are minted (`_mint`),
* and stop existing when they are burned (`_burn`).
*/function_exists(uint256 tokenId) internalviewvirtualreturns (bool) {
return _owners[tokenId] !=address(0);
}
/**
* @dev Returns whether `spender` is allowed to manage `tokenId`.
*
* Requirements:
*
* - `tokenId` must exist.
*/function_isApprovedOrOwner(address spender, uint256 tokenId) internalviewvirtualreturns (bool) {
require(_exists(tokenId), "ERC721: operator query for nonexistent token");
address owner = ERC721.ownerOf(tokenId);
return (spender == owner || getApproved(tokenId) == spender || isApprovedForAll(owner, spender));
}
/**
* @dev Safely mints `tokenId` and transfers it to `to`.
*
* Requirements:
*
* - `tokenId` must not exist.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/function_safeMint(address to, uint256 tokenId) internalvirtual{
_safeMint(to, tokenId, "");
}
/**
* @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
* forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
*/function_safeMint(address to,
uint256 tokenId,
bytesmemory _data
) internalvirtual{
_mint(to, tokenId);
require(
_checkOnERC721Received(address(0), to, tokenId, _data),
"ERC721: transfer to non ERC721Receiver implementer"
);
}
/**
* @dev Mints `tokenId` and transfers it to `to`.
*
* WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
*
* Requirements:
*
* - `tokenId` must not exist.
* - `to` cannot be the zero address.
*
* Emits a {Transfer} event.
*/function_mint(address to, uint256 tokenId) internalvirtual{
require(to !=address(0), "ERC721: mint to the zero address");
require(!_exists(tokenId), "ERC721: token already minted");
_beforeTokenTransfer(address(0), to, tokenId);
_balances[to] +=1;
_owners[tokenId] = to;
emit Transfer(address(0), to, tokenId);
}
/**
* @dev Destroys `tokenId`.
* The approval is cleared when the token is burned.
*
* Requirements:
*
* - `tokenId` must exist.
*
* Emits a {Transfer} event.
*/function_burn(uint256 tokenId) internalvirtual{
address owner = ERC721.ownerOf(tokenId);
_beforeTokenTransfer(owner, address(0), tokenId);
// Clear approvals
_approve(address(0), tokenId);
_balances[owner] -=1;
delete _owners[tokenId];
emit Transfer(owner, address(0), tokenId);
}
/**
* @dev Transfers `tokenId` from `from` to `to`.
* As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
*
* Emits a {Transfer} event.
*/function_transfer(addressfrom,
address to,
uint256 tokenId
) internalvirtual{
require(ERC721.ownerOf(tokenId) ==from, "ERC721: transfer of token that is not own");
require(to !=address(0), "ERC721: transfer to the zero address");
_beforeTokenTransfer(from, to, tokenId);
// Clear approvals from the previous owner
_approve(address(0), tokenId);
_balances[from] -=1;
_balances[to] +=1;
_owners[tokenId] = to;
emit Transfer(from, to, tokenId);
}
/**
* @dev Approve `to` to operate on `tokenId`
*
* Emits a {Approval} event.
*/function_approve(address to, uint256 tokenId) internalvirtual{
_tokenApprovals[tokenId] = to;
emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
}
/**
* @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(addressfrom,
address to,
uint256 tokenId,
bytesmemory _data
) privatereturns (bool) {
if (to.isContract()) {
try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, _data) returns (bytes4 retval) {
return retval == IERC721Receiver.onERC721Received.selector;
} catch (bytesmemory reason) {
if (reason.length==0) {
revert("ERC721: transfer to non ERC721Receiver implementer");
} else {
assembly {
revert(add(32, reason), mload(reason))
}
}
}
} else {
returntrue;
}
}
/**
* @dev Hook that is called before any token transfer. This includes minting
* and burning.
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, ``from``'s `tokenId` will be
* transferred to `to`.
* - When `from` is zero, `tokenId` will be minted for `to`.
* - When `to` is zero, ``from``'s `tokenId` will be burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/function_beforeTokenTransfer(addressfrom,
address to,
uint256 tokenId
) internalvirtual{}
}
Contract Source Code
File 7 of 15: ERC721URIStorage.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;import"../ERC721.sol";
/**
* @dev ERC721 token with storage based token URI management.
*/abstractcontractERC721URIStorageisERC721{
usingStringsforuint256;
// Optional mapping for token URIsmapping(uint256=>string) private _tokenURIs;
/**
* @dev See {IERC721Metadata-tokenURI}.
*/functiontokenURI(uint256 tokenId) publicviewvirtualoverridereturns (stringmemory) {
require(_exists(tokenId), "ERC721URIStorage: URI query for nonexistent token");
stringmemory _tokenURI = _tokenURIs[tokenId];
stringmemory base = _baseURI();
// If there is no base URI, return the token URI.if (bytes(base).length==0) {
return _tokenURI;
}
// If both are set, concatenate the baseURI and tokenURI (via abi.encodePacked).if (bytes(_tokenURI).length>0) {
returnstring(abi.encodePacked(base, _tokenURI));
}
returnsuper.tokenURI(tokenId);
}
/**
* @dev Sets `_tokenURI` as the tokenURI of `tokenId`.
*
* Requirements:
*
* - `tokenId` must exist.
*/function_setTokenURI(uint256 tokenId, stringmemory _tokenURI) internalvirtual{
require(_exists(tokenId), "ERC721URIStorage: URI set of nonexistent token");
_tokenURIs[tokenId] = _tokenURI;
}
/**
* @dev Destroys `tokenId`.
* The approval is cleared when the token is burned.
*
* Requirements:
*
* - `tokenId` must exist.
*
* Emits a {Transfer} event.
*/function_burn(uint256 tokenId) internalvirtualoverride{
super._burn(tokenId);
if (bytes(_tokenURIs[tokenId]).length!=0) {
delete _tokenURIs[tokenId];
}
}
}
Contract Source Code
File 8 of 15: IERC165.sol
// SPDX-License-Identifier: MITpragmasolidity ^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}.
*/interfaceIERC165{
/**
* @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.
*/functionsupportsInterface(bytes4 interfaceId) externalviewreturns (bool);
}
Contract Source Code
File 9 of 15: IERC2981.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.4;import"@openzeppelin/contracts/utils/introspection/IERC165.sol";
////// @dev Interface for the NFT Royalty Standard///interfaceIERC2981isIERC165{
/// ERC165 bytes to add to interface array - set in parent contract/// implementing this standard////// bytes4(keccak256("royaltyInfo(uint256,uint256)")) == 0x2a55205a/// bytes4 private constant _INTERFACE_ID_ERC2981 = 0x2a55205a;/// _registerInterface(_INTERFACE_ID_ERC2981);/// @notice Called with the sale price to determine how much royalty// is owed and to whom./// @param _tokenId - the NFT asset queried for royalty information/// @param _salePrice - the sale price of the NFT asset specified by _tokenId/// @return receiver - address of who should be sent the royalty payment/// @return royaltyAmount - the royalty payment amount for _salePricefunctionroyaltyInfo(uint256 _tokenId,
uint256 _salePrice
) externalviewreturns (address receiver,
uint256 royaltyAmount
);
}
Contract Source Code
File 10 of 15: IERC721.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;import"../../utils/introspection/IERC165.sol";
/**
* @dev Required interface of an ERC721 compliant contract.
*/interfaceIERC721isIERC165{
/**
* @dev Emitted when `tokenId` token is transferred from `from` to `to`.
*/eventTransfer(addressindexedfrom, addressindexed to, uint256indexed tokenId);
/**
* @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
*/eventApproval(addressindexed owner, addressindexed approved, uint256indexed tokenId);
/**
* @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
*/eventApprovalForAll(addressindexed owner, addressindexed operator, bool approved);
/**
* @dev Returns the number of tokens in ``owner``'s account.
*/functionbalanceOf(address owner) externalviewreturns (uint256 balance);
/**
* @dev Returns the owner of the `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/functionownerOf(uint256 tokenId) externalviewreturns (address owner);
/**
* @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.
*/functionsafeTransferFrom(addressfrom,
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.
*/functiontransferFrom(addressfrom,
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.
*/functionapprove(address to, uint256 tokenId) external;
/**
* @dev Returns the account approved for `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/functiongetApproved(uint256 tokenId) externalviewreturns (address operator);
/**
* @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.
*/functionsetApprovalForAll(address operator, bool _approved) external;
/**
* @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
*
* See {setApprovalForAll}
*/functionisApprovedForAll(address owner, address operator) externalviewreturns (bool);
/**
* @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.
*/functionsafeTransferFrom(addressfrom,
address to,
uint256 tokenId,
bytescalldata data
) external;
}
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;/**
* @title ERC721 token receiver interface
* @dev Interface for any contract that wants to support safeTransfers
* from ERC721 asset contracts.
*/interfaceIERC721Receiver{
/**
* @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`.
*/functiononERC721Received(address operator,
addressfrom,
uint256 tokenId,
bytescalldata data
) externalreturns (bytes4);
}
Contract Source Code
File 13 of 15: Ownable.sol
// SPDX-License-Identifier: MITpragmasolidity ^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.
*/abstractcontractOwnableisContext{
addressprivate _owner;
eventOwnershipTransferred(addressindexed previousOwner, addressindexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/constructor() {
_setOwner(_msgSender());
}
/**
* @dev Returns the address of the current owner.
*/functionowner() publicviewvirtualreturns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/modifieronlyOwner() {
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.
*/functionrenounceOwnership() publicvirtualonlyOwner{
_setOwner(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/functiontransferOwnership(address newOwner) publicvirtualonlyOwner{
require(newOwner !=address(0), "Ownable: new owner is the zero address");
_setOwner(newOwner);
}
function_setOwner(address newOwner) private{
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
Contract Source Code
File 14 of 15: Strings.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;/**
* @dev String operations.
*/libraryStrings{
bytes16privateconstant _HEX_SYMBOLS ="0123456789abcdef";
/**
* @dev Converts a `uint256` to its ASCII `string` decimal representation.
*/functiontoString(uint256 value) internalpurereturns (stringmemory) {
// Inspired by OraclizeAPI's implementation - MIT licence// https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.solif (value ==0) {
return"0";
}
uint256 temp = value;
uint256 digits;
while (temp !=0) {
digits++;
temp /=10;
}
bytesmemory buffer =newbytes(digits);
while (value !=0) {
digits -=1;
buffer[digits] =bytes1(uint8(48+uint256(value %10)));
value /=10;
}
returnstring(buffer);
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
*/functiontoHexString(uint256 value) internalpurereturns (stringmemory) {
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.
*/functiontoHexString(uint256 value, uint256 length) internalpurereturns (stringmemory) {
bytesmemory buffer =newbytes(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");
returnstring(buffer);
}
}
Contract Source Code
File 15 of 15: draft-EIP712.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;import"./ECDSA.sol";
/**
* @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
*
* The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
* thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
* they need in their contracts using a combination of `abi.encode` and `keccak256`.
*
* This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
* scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
* ({_hashTypedDataV4}).
*
* The implementation of the domain separator was designed to be as efficient as possible while still properly updating
* the chain id to protect against replay attacks on an eventual fork of the chain.
*
* NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
* https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
*
* _Available since v3.4._
*/abstractcontractEIP712{
/* solhint-disable var-name-mixedcase */// Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to// invalidate the cached domain separator if the chain id changes.bytes32privateimmutable _CACHED_DOMAIN_SEPARATOR;
uint256privateimmutable _CACHED_CHAIN_ID;
bytes32privateimmutable _HASHED_NAME;
bytes32privateimmutable _HASHED_VERSION;
bytes32privateimmutable _TYPE_HASH;
/* solhint-enable var-name-mixedcase *//**
* @dev Initializes the domain separator and parameter caches.
*
* The meaning of `name` and `version` is specified in
* https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
*
* - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
* - `version`: the current major version of the signing domain.
*
* NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
* contract upgrade].
*/constructor(stringmemory name, stringmemory version) {
bytes32 hashedName =keccak256(bytes(name));
bytes32 hashedVersion =keccak256(bytes(version));
bytes32 typeHash =keccak256(
"EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
);
_HASHED_NAME = hashedName;
_HASHED_VERSION = hashedVersion;
_CACHED_CHAIN_ID =block.chainid;
_CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator(typeHash, hashedName, hashedVersion);
_TYPE_HASH = typeHash;
}
/**
* @dev Returns the domain separator for the current chain.
*/function_domainSeparatorV4() internalviewreturns (bytes32) {
if (block.chainid== _CACHED_CHAIN_ID) {
return _CACHED_DOMAIN_SEPARATOR;
} else {
return _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION);
}
}
function_buildDomainSeparator(bytes32 typeHash,
bytes32 nameHash,
bytes32 versionHash
) privateviewreturns (bytes32) {
returnkeccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this)));
}
/**
* @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
* function returns the hash of the fully encoded EIP712 message for this domain.
*
* This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
*
* ```solidity
* bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
* keccak256("Mail(address to,string contents)"),
* mailTo,
* keccak256(bytes(mailContents))
* )));
* address signer = ECDSA.recover(digest, signature);
* ```
*/function_hashTypedDataV4(bytes32 structHash) internalviewvirtualreturns (bytes32) {
return ECDSA.toTypedDataHash(_domainSeparatorV4(), structHash);
}
}