Transaction Hash:
Block:
23676179 at Oct-28-2025 01:20:35 PM +UTC
Transaction Fee:
0.00000980437332834 ETH
$0.04
Gas Used:
26,030 Gas / 0.376656678 Gwei
Emitted Events:
| 492 |
0x35b4f07732fa5efb955962e62e7e0c283152f9cc.0x6e89d517057028190560dd200cf6bf792842861353d1173761dfa362e1c133f0( 0x6e89d517057028190560dd200cf6bf792842861353d1173761dfa362e1c133f0, 000000000000000000000000396343362be2a4da1ce0c1c210945346fb82aa49, 000000000000000000000000000000000000000000000000002179de545f2951, 0000000000000000000000000000000000000000000000000000000000000060, 0000000000000000000000000000000000000000000000000000000000000000 )
|
Account State Difference:
| Address | Before | After | State Difference | ||
|---|---|---|---|---|---|
| 0x35B4F077...83152f9cC | 252.526312664486130117 Eth | 252.535735334522805014 Eth | 0.009422670036674897 | ||
|
0x39634336...6fb82Aa49
Miner
| (quasarbuilder) |
10.928422553149479512 Eth
Nonce: 198357
|
10.918990078739476275 Eth
Nonce: 198358
| 0.009432474410003237 |
Execution Trace
ETH 0.009422670036674897
0x35b4f07732fa5efb955962e62e7e0c283152f9cc.CALL( )
- ETH 0.009422670036674897
WalletSimple.DELEGATECALL( )
// SPDX-License-Identifier: Apache-2.0
pragma solidity 0.8.10;
import './TransferHelper.sol';
import './ERC20Interface.sol';
import './IForwarder.sol';
/** ERC721, ERC1155 imports */
import '@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol';
import '@openzeppelin/contracts/token/ERC1155/utils/ERC1155Receiver.sol';
/**
*
* WalletSimple
* ============
*
* Basic multi-signer wallet designed for use in a co-signing environment where 2 signatures are required to move funds.
* Typically used in a 2-of-3 signing configuration. Uses ecrecover to allow for 2 signatures in a single transaction.
*
* The first signature is created on the operation hash (see Data Formats) and passed to sendMultiSig/sendMultiSigToken
* The signer is determined by verifyMultiSig().
*
* The second signature is created by the submitter of the transaction and determined by msg.signer.
*
* Data Formats
* ============
*
* The signature is created with ethereumjs-util.ecsign(operationHash).
* Like the eth_sign RPC call, it packs the values as a 65-byte array of [r, s, v].
* Unlike eth_sign, the message is not prefixed.
*
* The operationHash the result of keccak256(prefix, toAddress, value, data, expireTime).
* For ether transactions, `prefix` is "ETHER".
* For token transaction, `prefix` is "ERC20" and `data` is the tokenContractAddress.
*
*
*/
contract WalletSimple is IERC721Receiver, ERC1155Receiver {
// Events
event Deposited(address from, uint256 value, bytes data);
event SafeModeActivated(address msgSender);
event Transacted(
address msgSender, // Address of the sender of the message initiating the transaction
address otherSigner, // Address of the signer (second signature) used to initiate the transaction
bytes32 operation, // Operation hash (see Data Formats)
address toAddress, // The address the transaction was sent to
uint256 value, // Amount of Wei sent to the address
bytes data // Data sent when invoking the transaction
);
event BatchTransfer(address sender, address recipient, uint256 value);
// this event shows the other signer and the operation hash that they signed
// specific batch transfer events are emitted in Batcher
event BatchTransacted(
address msgSender, // Address of the sender of the message initiating the transaction
address otherSigner, // Address of the signer (second signature) used to initiate the transaction
bytes32 operation // Operation hash (see Data Formats)
);
// Public fields
mapping(address => bool) public signers; // The addresses that can co-sign transactions on the wallet
bool public safeMode = false; // When active, wallet may only send to signer addresses
bool public initialized = false; // True if the contract has been initialized
// Internal fields
uint256 private constant MAX_SEQUENCE_ID_INCREASE = 10000;
uint256 constant SEQUENCE_ID_WINDOW_SIZE = 10;
uint256[SEQUENCE_ID_WINDOW_SIZE] recentSequenceIds;
/**
* Set up a simple multi-sig wallet by specifying the signers allowed to be used on this wallet.
* 2 signers will be required to send a transaction from this wallet.
* Note: The sender is NOT automatically added to the list of signers.
* Signers CANNOT be changed once they are set
*
* @param allowedSigners An array of signers on the wallet
*/
function init(address[] calldata allowedSigners) external onlyUninitialized {
require(allowedSigners.length == 3, 'Invalid number of signers');
for (uint8 i = 0; i < allowedSigners.length; i++) {
require(allowedSigners[i] != address(0), 'Invalid signer');
signers[allowedSigners[i]] = true;
}
initialized = true;
}
/**
* Get the network identifier that signers must sign over
* This provides protection signatures being replayed on other chains
* This must be a virtual function because chain-specific contracts will need
* to override with their own network ids. It also can't be a field
* to allow this contract to be used by proxy with delegatecall, which will
* not pick up on state variables
*/
function getNetworkId() internal virtual pure returns (string memory) {
return 'ETHER';
}
/**
* Get the network identifier that signers must sign over for token transfers
* This provides protection signatures being replayed on other chains
* This must be a virtual function because chain-specific contracts will need
* to override with their own network ids. It also can't be a field
* to allow this contract to be used by proxy with delegatecall, which will
* not pick up on state variables
*/
function getTokenNetworkId() internal virtual pure returns (string memory) {
return 'ERC20';
}
/**
* Get the network identifier that signers must sign over for batch transfers
* This provides protection signatures being replayed on other chains
* This must be a virtual function because chain-specific contracts will need
* to override with their own network ids. It also can't be a field
* to allow this contract to be used by proxy with delegatecall, which will
* not pick up on state variables
*/
function getBatchNetworkId() internal virtual pure returns (string memory) {
return 'ETHER-Batch';
}
/**
* Determine if an address is a signer on this wallet
* @param signer address to check
* returns boolean indicating whether address is signer or not
*/
function isSigner(address signer) public view returns (bool) {
return signers[signer];
}
/**
* Modifier that will execute internal code block only if the sender is an authorized signer on this wallet
*/
modifier onlySigner {
require(isSigner(msg.sender), 'Non-signer in onlySigner method');
_;
}
/**
* Modifier that will execute internal code block only if the contract has not been initialized yet
*/
modifier onlyUninitialized {
require(!initialized, 'Contract already initialized');
_;
}
/**
* Gets called when a transaction is received with data that does not match any other method
*/
fallback() external payable {
if (msg.value > 0) {
// Fire deposited event if we are receiving funds
emit Deposited(msg.sender, msg.value, msg.data);
}
}
/**
* Gets called when a transaction is received with ether and no data
*/
receive() external payable {
if (msg.value > 0) {
// Fire deposited event if we are receiving funds
// message data is always empty for receive. If there is data it is sent to fallback function.
emit Deposited(msg.sender, msg.value, '');
}
}
/**
* Execute a multi-signature transaction from this wallet using 2 signers: one from msg.sender and the other from ecrecover.
* Sequence IDs are numbers starting from 1. They are used to prevent replay attacks and may not be repeated.
*
* @param toAddress the destination address to send an outgoing transaction
* @param value the amount in Wei to be sent
* @param data the data to send to the toAddress when invoking the transaction
* @param expireTime the number of seconds since 1970 for which this transaction is valid
* @param sequenceId the unique sequence id obtainable from getNextSequenceId
* @param signature see Data Formats
*/
function sendMultiSig(
address toAddress,
uint256 value,
bytes calldata data,
uint256 expireTime,
uint256 sequenceId,
bytes calldata signature
) external onlySigner {
// Verify the other signer
bytes32 operationHash = keccak256(
abi.encodePacked(
getNetworkId(),
toAddress,
value,
data,
expireTime,
sequenceId
)
);
address otherSigner = verifyMultiSig(
toAddress,
operationHash,
signature,
expireTime,
sequenceId
);
// Success, send the transaction
(bool success, ) = toAddress.call{ value: value }(data);
require(success, 'Call execution failed');
emit Transacted(
msg.sender,
otherSigner,
operationHash,
toAddress,
value,
data
);
}
/**
* Execute a batched multi-signature transaction from this wallet using 2 signers: one from msg.sender and the other from ecrecover.
* Sequence IDs are numbers starting from 1. They are used to prevent replay attacks and may not be repeated.
* The recipients and values to send are encoded in two arrays, where for index i, recipients[i] will be sent values[i].
*
* @param recipients The list of recipients to send to
* @param values The list of values to send to
* @param expireTime the number of seconds since 1970 for which this transaction is valid
* @param sequenceId the unique sequence id obtainable from getNextSequenceId
* @param signature see Data Formats
*/
function sendMultiSigBatch(
address[] calldata recipients,
uint256[] calldata values,
uint256 expireTime,
uint256 sequenceId,
bytes calldata signature
) external onlySigner {
require(recipients.length != 0, 'Not enough recipients');
require(
recipients.length == values.length,
'Unequal recipients and values'
);
require(recipients.length < 256, 'Too many recipients, max 255');
// Verify the other signer
bytes32 operationHash = keccak256(
abi.encodePacked(
getBatchNetworkId(),
recipients,
values,
expireTime,
sequenceId
)
);
// the first parameter (toAddress) is used to ensure transactions in safe mode only go to a signer
// if in safe mode, we should use normal sendMultiSig to recover, so this check will always fail if in safe mode
require(!safeMode, 'Batch in safe mode');
address otherSigner = verifyMultiSig(
address(0x0),
operationHash,
signature,
expireTime,
sequenceId
);
batchTransfer(recipients, values);
emit BatchTransacted(msg.sender, otherSigner, operationHash);
}
/**
* Transfer funds in a batch to each of recipients
* @param recipients The list of recipients to send to
* @param values The list of values to send to recipients.
* The recipient with index i in recipients array will be sent values[i].
* Thus, recipients and values must be the same length
*/
function batchTransfer(
address[] calldata recipients,
uint256[] calldata values
) internal {
for (uint256 i = 0; i < recipients.length; i++) {
require(address(this).balance >= values[i], 'Insufficient funds');
(bool success, ) = recipients[i].call{ value: values[i] }('');
require(success, 'Call failed');
emit BatchTransfer(msg.sender, recipients[i], values[i]);
}
}
/**
* Execute a multi-signature token transfer from this wallet using 2 signers: one from msg.sender and the other from ecrecover.
* Sequence IDs are numbers starting from 1. They are used to prevent replay attacks and may not be repeated.
*
* @param toAddress the destination address to send an outgoing transaction
* @param value the amount in tokens to be sent
* @param tokenContractAddress the address of the erc20 token contract
* @param expireTime the number of seconds since 1970 for which this transaction is valid
* @param sequenceId the unique sequence id obtainable from getNextSequenceId
* @param signature see Data Formats
*/
function sendMultiSigToken(
address toAddress,
uint256 value,
address tokenContractAddress,
uint256 expireTime,
uint256 sequenceId,
bytes calldata signature
) external onlySigner {
// Verify the other signer
bytes32 operationHash = keccak256(
abi.encodePacked(
getTokenNetworkId(),
toAddress,
value,
tokenContractAddress,
expireTime,
sequenceId
)
);
verifyMultiSig(toAddress, operationHash, signature, expireTime, sequenceId);
TransferHelper.safeTransfer(tokenContractAddress, toAddress, value);
}
/**
* Execute a token flush from one of the forwarder addresses. This transfer needs only a single signature and can be done by any signer
*
* @param forwarderAddress the address of the forwarder address to flush the tokens from
* @param tokenContractAddress the address of the erc20 token contract
*/
function flushForwarderTokens(
address payable forwarderAddress,
address tokenContractAddress
) external onlySigner {
IForwarder forwarder = IForwarder(forwarderAddress);
forwarder.flushTokens(tokenContractAddress);
}
/**
* Execute a ERC721 token flush from one of the forwarder addresses. This transfer needs only a single signature and can be done by any signer
*
* @param forwarderAddress the address of the forwarder address to flush the tokens from
* @param tokenContractAddress the address of the erc20 token contract
*/
function flushERC721ForwarderTokens(
address payable forwarderAddress,
address tokenContractAddress,
uint256 tokenId
) external onlySigner {
IForwarder forwarder = IForwarder(forwarderAddress);
forwarder.flushERC721Token(tokenContractAddress, tokenId);
}
/**
* Execute a ERC1155 batch token flush from one of the forwarder addresses.
* This transfer needs only a single signature and can be done by any signer.
*
* @param forwarderAddress the address of the forwarder address to flush the tokens from
* @param tokenContractAddress the address of the erc1155 token contract
*/
function batchFlushERC1155ForwarderTokens(
address payable forwarderAddress,
address tokenContractAddress,
uint256[] calldata tokenIds
) external onlySigner {
IForwarder forwarder = IForwarder(forwarderAddress);
forwarder.batchFlushERC1155Tokens(tokenContractAddress, tokenIds);
}
/**
* Execute a ERC1155 token flush from one of the forwarder addresses.
* This transfer needs only a single signature and can be done by any signer.
*
* @param forwarderAddress the address of the forwarder address to flush the tokens from
* @param tokenContractAddress the address of the erc1155 token contract
* @param tokenId the token id associated with the ERC1155
*/
function flushERC1155ForwarderTokens(
address payable forwarderAddress,
address tokenContractAddress,
uint256 tokenId
) external onlySigner {
IForwarder forwarder = IForwarder(forwarderAddress);
forwarder.flushERC1155Tokens(tokenContractAddress, tokenId);
}
/**
* Sets the autoflush 721 parameter on the forwarder.
*
* @param forwarderAddress the address of the forwarder to toggle.
* @param autoFlush whether to autoflush erc721 tokens
*/
function setAutoFlush721(address forwarderAddress, bool autoFlush)
external
onlySigner
{
IForwarder forwarder = IForwarder(forwarderAddress);
forwarder.setAutoFlush721(autoFlush);
}
/**
* Sets the autoflush 721 parameter on the forwarder.
*
* @param forwarderAddress the address of the forwarder to toggle.
* @param autoFlush whether to autoflush erc1155 tokens
*/
function setAutoFlush1155(address forwarderAddress, bool autoFlush)
external
onlySigner
{
IForwarder forwarder = IForwarder(forwarderAddress);
forwarder.setAutoFlush1155(autoFlush);
}
/**
* Do common multisig verification for both eth sends and erc20token transfers
*
* @param toAddress the destination address to send an outgoing transaction
* @param operationHash see Data Formats
* @param signature see Data Formats
* @param expireTime the number of seconds since 1970 for which this transaction is valid
* @param sequenceId the unique sequence id obtainable from getNextSequenceId
* returns address that has created the signature
*/
function verifyMultiSig(
address toAddress,
bytes32 operationHash,
bytes calldata signature,
uint256 expireTime,
uint256 sequenceId
) private returns (address) {
address otherSigner = recoverAddressFromSignature(operationHash, signature);
// Verify if we are in safe mode. In safe mode, the wallet can only send to signers
require(!safeMode || isSigner(toAddress), 'External transfer in safe mode');
// Verify that the transaction has not expired
require(expireTime >= block.timestamp, 'Transaction expired');
// Try to insert the sequence ID. Will revert if the sequence id was invalid
tryInsertSequenceId(sequenceId);
require(isSigner(otherSigner), 'Invalid signer');
require(otherSigner != msg.sender, 'Signers cannot be equal');
return otherSigner;
}
/**
* ERC721 standard callback function for when a ERC721 is transfered.
*
* @param _operator The address of the nft contract
* @param _from The address of the sender
* @param _tokenId The token id of the nft
* @param _data Additional data with no specified format, sent in call to `_to`
*/
function onERC721Received(
address _operator,
address _from,
uint256 _tokenId,
bytes memory _data
) external virtual override returns (bytes4) {
return this.onERC721Received.selector;
}
/**
* @inheritdoc IERC1155Receiver
*/
function onERC1155Received(
address _operator,
address _from,
uint256 id,
uint256 value,
bytes calldata data
) external virtual override returns (bytes4) {
return this.onERC1155Received.selector;
}
/**
* @inheritdoc IERC1155Receiver
*/
function onERC1155BatchReceived(
address _operator,
address _from,
uint256[] calldata ids,
uint256[] calldata values,
bytes calldata data
) external virtual override returns (bytes4) {
return this.onERC1155BatchReceived.selector;
}
/**
* Irrevocably puts contract into safe mode. When in this mode, transactions may only be sent to signing addresses.
*/
function activateSafeMode() external onlySigner {
safeMode = true;
emit SafeModeActivated(msg.sender);
}
/**
* Gets signer's address using ecrecover
* @param operationHash see Data Formats
* @param signature see Data Formats
* returns address recovered from the signature
*/
function recoverAddressFromSignature(
bytes32 operationHash,
bytes memory signature
) private pure returns (address) {
require(signature.length == 65, 'Invalid signature - wrong length');
// We need to unpack the signature, which is given as an array of 65 bytes (like eth.sign)
bytes32 r;
bytes32 s;
uint8 v;
// solhint-disable-next-line
assembly {
r := mload(add(signature, 32))
s := mload(add(signature, 64))
v := and(mload(add(signature, 65)), 255)
}
if (v < 27) {
v += 27; // Ethereum versions are 27 or 28 as opposed to 0 or 1 which is submitted by some signing libs
}
// protect against signature malleability
// S value must be in the lower half orader
// reference: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/051d340171a93a3d401aaaea46b4b62fa81e5d7c/contracts/cryptography/ECDSA.sol#L53
require(
uint256(s) <=
0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,
"ECDSA: invalid signature 's' value"
);
// note that this returns 0 if the signature is invalid
// Since 0x0 can never be a signer, when the recovered signer address
// is checked against our signer list, that 0x0 will cause an invalid signer failure
return ecrecover(operationHash, v, r, s);
}
/**
* Verify that the sequence id has not been used before and inserts it. Throws if the sequence ID was not accepted.
* We collect a window of up to 10 recent sequence ids, and allow any sequence id that is not in the window and
* greater than the minimum element in the window.
* @param sequenceId to insert into array of stored ids
*/
function tryInsertSequenceId(uint256 sequenceId) private onlySigner {
// Keep a pointer to the lowest value element in the window
uint256 lowestValueIndex = 0;
// fetch recentSequenceIds into memory for function context to avoid unnecessary sloads
uint256[SEQUENCE_ID_WINDOW_SIZE] memory _recentSequenceIds
= recentSequenceIds;
for (uint256 i = 0; i < SEQUENCE_ID_WINDOW_SIZE; i++) {
require(_recentSequenceIds[i] != sequenceId, 'Sequence ID already used');
if (_recentSequenceIds[i] < _recentSequenceIds[lowestValueIndex]) {
lowestValueIndex = i;
}
}
// The sequence ID being used is lower than the lowest value in the window
// so we cannot accept it as it may have been used before
require(
sequenceId > _recentSequenceIds[lowestValueIndex],
'Sequence ID below window'
);
// Block sequence IDs which are much higher than the lowest value
// This prevents people blocking the contract by using very large sequence IDs quickly
require(
sequenceId <=
(_recentSequenceIds[lowestValueIndex] + MAX_SEQUENCE_ID_INCREASE),
'Sequence ID above maximum'
);
recentSequenceIds[lowestValueIndex] = sequenceId;
}
/**
* Gets the next available sequence ID for signing when using executeAndConfirm
* returns the sequenceId one higher than the highest currently stored
*/
function getNextSequenceId() external view returns (uint256) {
uint256 highestSequenceId = 0;
for (uint256 i = 0; i < SEQUENCE_ID_WINDOW_SIZE; i++) {
if (recentSequenceIds[i] > highestSequenceId) {
highestSequenceId = recentSequenceIds[i];
}
}
return highestSequenceId + 1;
}
}
// SPDX-License-Identifier: GPL-3.0-or-later
// source: https://github.com/Uniswap/solidity-lib/blob/master/contracts/libraries/TransferHelper.sol
pragma solidity 0.8.10;
import '@openzeppelin/contracts/utils/Address.sol';
// helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false
library TransferHelper {
function safeTransfer(
address token,
address to,
uint256 value
) internal {
// bytes4(keccak256(bytes('transfer(address,uint256)')));
(bool success, bytes memory data) = token.call(
abi.encodeWithSelector(0xa9059cbb, to, value)
);
require(
success && (data.length == 0 || abi.decode(data, (bool))),
'TransferHelper::safeTransfer: transfer failed'
);
}
function safeTransferFrom(
address token,
address from,
address to,
uint256 value
) internal {
// bytes4(keccak256(bytes('transferFrom(address,address,uint256)')));
(bool success, bytes memory returndata) = token.call(
abi.encodeWithSelector(0x23b872dd, from, to, value)
);
Address.verifyCallResult(
success,
returndata,
'TransferHelper::transferFrom: transferFrom failed'
);
}
}
// SPDX-License-Identifier: UNLICENSED
pragma solidity 0.8.10;
/**
* Contract that exposes the needed erc20 token functions
*/
abstract contract ERC20Interface {
// Send _value amount of tokens to address _to
function transfer(address _to, uint256 _value)
public
virtual
returns (bool success);
// Get the account balance of another account with address _owner
function balanceOf(address _owner)
public
virtual
view
returns (uint256 balance);
}
pragma solidity ^0.8.0;
import '@openzeppelin/contracts/utils/introspection/IERC165.sol';
interface IForwarder is IERC165 {
/**
* Sets the autoflush721 parameter.
*
* @param autoFlush whether to autoflush erc721 tokens
*/
function setAutoFlush721(bool autoFlush) external;
/**
* Sets the autoflush1155 parameter.
*
* @param autoFlush whether to autoflush erc1155 tokens
*/
function setAutoFlush1155(bool autoFlush) external;
/**
* Execute a token transfer of the full balance from the forwarder token to the parent address
*
* @param tokenContractAddress the address of the erc20 token contract
*/
function flushTokens(address tokenContractAddress) external;
/**
* Execute a nft transfer from the forwarder to the parent address
*
* @param tokenContractAddress the address of the ERC721 NFT contract
* @param tokenId The token id of the nft
*/
function flushERC721Token(address tokenContractAddress, uint256 tokenId)
external;
/**
* Execute a nft transfer from the forwarder to the parent address.
*
* @param tokenContractAddress the address of the ERC1155 NFT contract
* @param tokenId The token id of the nft
*/
function flushERC1155Tokens(address tokenContractAddress, uint256 tokenId)
external;
/**
* Execute a batch nft transfer from the forwarder to the parent address.
*
* @param tokenContractAddress the address of the ERC1155 NFT contract
* @param tokenIds The token ids of the nfts
*/
function batchFlushERC1155Tokens(
address tokenContractAddress,
uint256[] calldata tokenIds
) external;
}
// 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 (token/ERC1155/utils/ERC1155Receiver.sol)
pragma solidity ^0.8.0;
import "../IERC1155Receiver.sol";
import "../../../utils/introspection/ERC165.sol";
/**
* @dev _Available since v3.1._
*/
abstract contract ERC1155Receiver is ERC165, IERC1155Receiver {
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
return interfaceId == type(IERC1155Receiver).interfaceId || super.supportsInterface(interfaceId);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Address.sol)
pragma solidity ^0.8.0;
/**
* @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
* ====
*/
function isContract(address account) internal view returns (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].
*/
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 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
// OpenZeppelin Contracts v4.4.1 (token/ERC1155/IERC1155Receiver.sol)
pragma solidity ^0.8.0;
import "../../utils/introspection/IERC165.sol";
/**
* @dev _Available since v3.1._
*/
interface IERC1155Receiver is IERC165 {
/**
@dev Handles the receipt of a single ERC1155 token type. This function is
called at the end of a `safeTransferFrom` after the balance has been updated.
To accept the transfer, this must return
`bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))`
(i.e. 0xf23a6e61, or its own function selector).
@param operator The address which initiated the transfer (i.e. msg.sender)
@param from The address which previously owned the token
@param id The ID of the token being transferred
@param value The amount of tokens being transferred
@param data Additional data with no specified format
@return `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))` if transfer is allowed
*/
function onERC1155Received(
address operator,
address from,
uint256 id,
uint256 value,
bytes calldata data
) external returns (bytes4);
/**
@dev Handles the receipt of a multiple ERC1155 token types. This function
is called at the end of a `safeBatchTransferFrom` after the balances have
been updated. To accept the transfer(s), this must return
`bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))`
(i.e. 0xbc197c81, or its own function selector).
@param operator The address which initiated the batch transfer (i.e. msg.sender)
@param from The address which previously owned the token
@param ids An array containing ids of each token being transferred (order and length must match values array)
@param values An array containing amounts of each token being transferred (order and length must match ids array)
@param data Additional data with no specified format
@return `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))` if transfer is allowed
*/
function onERC1155BatchReceived(
address operator,
address from,
uint256[] calldata ids,
uint256[] calldata values,
bytes calldata data
) external returns (bytes4);
}
// 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;
}
}