Contract Address Details

0x777777772C24e6CD34B464D1d71616C444254537

Creator
0xde312a–6dc45b at 0xa9d226–2315b2
Implementation
0x88e7ab71cc18b9f6fb091fc53fe3be467808e0f6
Balance
0.002394 ELA
Tokens
Fetching tokens...
Transactions
Transfers
Gas Used
Last Balance Update
24293757
Contract is not verified. However, we found a verified contract with the same bytecode in Blockscout DB 0x840bafdc40d88f54db41327fe1c85241f9151243.
All metadata displayed below is from that contract. In order to verify current contract, click Verify & Publish button
Contract name:
WitnetProxy




Optimization enabled
true
Compiler version
v0.8.17+commit.8df45f5f




Optimization runs
200
Verified at
2023-04-26 12:59:07.771119Z

Contract source code

// SPDX-License-Identifier: MIT
pragma solidity >=0.7.0 <0.9.0;
pragma experimental ABIEncoderV2;
/**
* @dev Collection of functions related to the address type
*/
library AddressUpgradeable {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*
* [IMPORTANT]
* ====
* You shouldn't rely on `isContract` to protect against flash loan attacks!
*
* Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
* like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
* constructor.
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize/address.code.length, which returns 0
// for contracts in construction, since the code is only stored at the end
// of the constructor execution.
return account.code.length > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, "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");
(bool success, bytes memory returndata) = target.call{value: value}(data);
return verifyCallResultFromTarget(target, 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) {
(bool success, bytes memory returndata) = target.staticcall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
* the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
*
* _Available since v4.8._
*/
function verifyCallResultFromTarget(
address target,
bool success,
bytes memory returndata,
string memory errorMessage
) internal view returns (bytes memory) {
if (success) {
if (returndata.length == 0) {
// only check isContract if the call was successful and the return data is empty
// otherwise we already know that it was a contract
require(isContract(target), "Address: call to non-contract");
}
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
/**
* @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason or 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 {
_revert(returndata, errorMessage);
}
}
function _revert(bytes memory returndata, string memory errorMessage) private pure {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
/// @solidity memory-safe-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
/**
* @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
* behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
* external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
* function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
*
* The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
* reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
* case an upgrade adds a module that needs to be initialized.
*
* For example:
*
* [.hljs-theme-light.nopadding]
* ```
* contract MyToken is ERC20Upgradeable {
* function initialize() initializer public {
* __ERC20_init("MyToken", "MTK");
* }
* }
* contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
* function initializeV2() reinitializer(2) public {
* __ERC20Permit_init("MyToken");
* }
* }
* ```
*
* TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
* possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
*
* CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
* that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
*
* [CAUTION]
* ====
* Avoid leaving a contract uninitialized.
*
* An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
* contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
* the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
*
* [.hljs-theme-light.nopadding]
* ```
* /// @custom:oz-upgrades-unsafe-allow constructor
* constructor() {
* _disableInitializers();
* }
* ```
* ====
*/
abstract contract Initializable {
/**
* @dev Indicates that the contract has been initialized.
* @custom:oz-retyped-from bool
*/
uint8 private _initialized;
/**
* @dev Indicates that the contract is in the process of being initialized.
*/
bool private _initializing;
/**
* @dev Triggered when the contract has been initialized or reinitialized.
*/
event Initialized(uint8 version);
/**
* @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
* `onlyInitializing` functions can be used to initialize parent contracts.
*
* Similar to `reinitializer(1)`, except that functions marked with `initializer` can be nested in the context of a
* constructor.
*
* Emits an {Initialized} event.
*/
modifier initializer() {
bool isTopLevelCall = !_initializing;
require(
(isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
"Initializable: contract is already initialized"
);
_initialized = 1;
if (isTopLevelCall) {
_initializing = true;
}
_;
if (isTopLevelCall) {
_initializing = false;
emit Initialized(1);
}
}
/**
* @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
* contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
* used to initialize parent contracts.
*
* A reinitializer may be used after the original initialization step. This is essential to configure modules that
* are added through upgrades and that require initialization.
*
* When `version` is 1, this modifier is similar to `initializer`, except that functions marked with `reinitializer`
* cannot be nested. If one is invoked in the context of another, execution will revert.
*
* Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
* a contract, executing them in the right order is up to the developer or operator.
*
* WARNING: setting the version to 255 will prevent any future reinitialization.
*
* Emits an {Initialized} event.
*/
modifier reinitializer(uint8 version) {
require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
_initialized = version;
_initializing = true;
_;
_initializing = false;
emit Initialized(version);
}
/**
* @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
* {initializer} and {reinitializer} modifiers, directly or indirectly.
*/
modifier onlyInitializing() {
require(_initializing, "Initializable: contract is not initializing");
_;
}
/**
* @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
* Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
* to any version. It is recommended to use this to lock implementation contracts that are designed to be called
* through proxies.
*
* Emits an {Initialized} event the first time it is successfully executed.
*/
function _disableInitializers() internal virtual {
require(!_initializing, "Initializable: contract is initializing");
if (_initialized < type(uint8).max) {
_initialized = type(uint8).max;
emit Initialized(type(uint8).max);
}
}
/**
* @dev Internal function that returns the initialized version. Returns `_initialized`
*/
function _getInitializedVersion() internal view returns (uint8) {
return _initialized;
}
/**
* @dev Internal function that returns the initialized version. Returns `_initializing`
*/
function _isInitializing() internal view returns (bool) {
return _initializing;
}
}
abstract contract Proxiable {
/// @dev Complying with EIP-1822: Universal Upgradeable Proxy Standard (UUPS)
/// @dev See https://eips.ethereum.org/EIPS/eip-1822.
function proxiableUUID() virtual external view returns (bytes32);
struct ProxiableSlot {
address implementation;
address proxy;
}
function __implementation() internal view returns (address) {
return __proxiable().implementation;
}
function __proxy() internal view returns (address) {
return __proxiable().proxy;
}
function __proxiable() internal pure returns (ProxiableSlot storage proxiable) {
assembly {
// bytes32(uint256(keccak256('eip1967.proxy.implementation')) - 1)
proxiable.slot := 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc
}
}
}
abstract contract Upgradeable is Initializable, Proxiable {
address internal immutable _BASE;
bytes32 internal immutable _CODEHASH;
bool internal immutable _UPGRADABLE;
modifier onlyDelegateCalls virtual {
require(
address(this) != _BASE,
"Upgradeable: not a delegate call"
);
_;
}
/// Emitted every time the contract gets upgraded.
/// @param from The address who ordered the upgrading. Namely, the WRB operator in "trustable" implementations.
/// @param baseAddr The address of the new implementation contract.
/// @param baseCodehash The EVM-codehash of the new implementation contract.
/// @param versionTag Ascii-encoded version literal with which the implementation deployer decided to tag it.
event Upgraded(
address indexed from,
address indexed baseAddr,
bytes32 indexed baseCodehash,
string versionTag
);
constructor (bool _isUpgradable) {
address _base = address(this);
bytes32 _codehash;
assembly {
_codehash := extcodehash(_base)
}
_BASE = _base;
_CODEHASH = _codehash;
_UPGRADABLE = _isUpgradable;
}
/// @dev Retrieves base contract. Differs from address(this) when called via delegate-proxy pattern.
function base() public view returns (address) {
return _BASE;
}
/// @dev Retrieves the immutable codehash of this contract, even if invoked as delegatecall.
function codehash() public view returns (bytes32) {
return _CODEHASH;
}
/// @dev Determines whether the logic of this contract is potentially upgradable.
function isUpgradable() public view returns (bool) {
return _UPGRADABLE;
}
/// @dev Tells whether provided address could eventually upgrade the contract.
function isUpgradableFrom(address from) virtual external view returns (bool);
/// @notice Re-initialize contract's storage context upon a new upgrade from a proxy.
/// @dev Must fail when trying to upgrade to same logic contract more than once.
function initialize(bytes memory) virtual external;
/// @dev Retrieves human-redable named version of current implementation.
function version() virtual public view returns (string memory);
}
/// @title WitnetProxy: upgradable delegate-proxy contract.
/// @author The Witnet Foundation.
contract WitnetProxy {
/// Event emitted every time the implementation gets updated.
event Upgraded(address indexed implementation);
/// Constructor with no params as to ease eventual support of Singleton pattern (i.e. ERC-2470).
constructor () {}
receive() virtual external payable {}
/// Payable fallback accepts delegating calls to payable functions.
fallback() external payable { /* solhint-disable no-complex-fallback */
address _implementation = implementation();
assembly { /* solhint-disable avoid-low-level-calls */
// Gas optimized delegate call to 'implementation' contract.
// Note: `msg.data`, `msg.sender` and `msg.value` will be passed over
// to actual implementation of `msg.sig` within `implementation` contract.
let ptr := mload(0x40)
calldatacopy(ptr, 0, calldatasize())
let result := delegatecall(gas(), _implementation, ptr, calldatasize(), 0, 0)
let size := returndatasize()
returndatacopy(ptr, 0, size)
switch result
case 0 {
// pass back revert message:
revert(ptr, size)
}
default {
// pass back same data as returned by 'implementation' contract:
return(ptr, size)
}
}
}
/// Returns proxy's current implementation address.
function implementation() public view returns (address) {
return __proxySlot().implementation;
}
/// Upgrades the `implementation` address.
/// @param _newImplementation New implementation address.
/// @param _initData Raw data with which new implementation will be initialized.
/// @return Returns whether new implementation would be further upgradable, or not.
function upgradeTo(address _newImplementation, bytes memory _initData)
public returns (bool)
{
// New implementation cannot be null:
require(_newImplementation != address(0), "WitnetProxy: null implementation");
address _oldImplementation = implementation();
if (_oldImplementation != address(0)) {
// New implementation address must differ from current one:
require(_newImplementation != _oldImplementation, "WitnetProxy: nothing to upgrade");
// Assert whether current implementation is intrinsically upgradable:
try Upgradeable(_oldImplementation).isUpgradable() returns (bool _isUpgradable) {
require(_isUpgradable, "WitnetProxy: not upgradable");
} catch {
revert("WitnetProxy: unable to check upgradability");
}
// Assert whether current implementation allows `msg.sender` to upgrade the proxy:
(bool _wasCalled, bytes memory _result) = _oldImplementation.delegatecall(
abi.encodeWithSignature(
"isUpgradableFrom(address)",
msg.sender
)
);
require(_wasCalled, "WitnetProxy: not compliant");
require(abi.decode(_result, (bool)), "WitnetProxy: not authorized");
require(
Upgradeable(_oldImplementation).proxiableUUID() == Upgradeable(_newImplementation).proxiableUUID(),
"WitnetProxy: proxiableUUIDs mismatch"
);
}
// Initialize new implementation within proxy-context storage:
(bool _wasInitialized,) = _newImplementation.delegatecall(
abi.encodeWithSignature(
"initialize(bytes)",
_initData
)
);
require(_wasInitialized, "WitnetProxy: unable to initialize");
// If all checks and initialization pass, update implementation address:
__proxySlot().implementation = _newImplementation;
emit Upgraded(_newImplementation);
// Asserts new implementation complies w/ minimal implementation of Upgradeable interface:
try Upgradeable(_newImplementation).isUpgradable() returns (bool _isUpgradable) {
return _isUpgradable;
}
catch {
revert ("WitnetProxy: not compliant");
}
}
/// @dev Complying with EIP-1967, retrieves storage struct containing proxy's current implementation address.
function __proxySlot() private pure returns (Proxiable.ProxiableSlot storage _slot) {
assembly {
// bytes32(uint256(keccak256('eip1967.proxy.implementation')) - 1)
_slot.slot := 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc
}
}
}

Contract ABI

[{"type":"constructor","stateMutability":"nonpayable","inputs":[]},{"type":"event","name":"Upgraded","inputs":[{"type":"address","name":"implementation","internalType":"address","indexed":true}],"anonymous":false},{"type":"fallback","stateMutability":"payable"},{"type":"function","stateMutability":"view","outputs":[{"type":"address","name":"","internalType":"address"}],"name":"implementation","inputs":[]},{"type":"function","stateMutability":"nonpayable","outputs":[{"type":"bool","name":"","internalType":"bool"}],"name":"upgradeTo","inputs":[{"type":"address","name":"_newImplementation","internalType":"address"},{"type":"bytes","name":"_initData","internalType":"bytes"}]},{"type":"receive","stateMutability":"payable"}]
            

Deployed ByteCode

Verify & Publish
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