Contract Name:
TimelockController
Contract Source Code:
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/AccessControl.sol)
pragma solidity ^0.8.0;
import "./IAccessControl.sol";
import "../utils/Context.sol";
import "../utils/Strings.sol";
import "../utils/introspection/ERC165.sol";
/**
* @dev Contract module that allows children to implement role-based access
* control mechanisms. This is a lightweight version that doesn't allow enumerating role
* members except through off-chain means by accessing the contract event logs. Some
* applications may benefit from on-chain enumerability, for those cases see
* {AccessControlEnumerable}.
*
* Roles are referred to by their `bytes32` identifier. These should be exposed
* in the external API and be unique. The best way to achieve this is by
* using `public constant` hash digests:
*
* ```
* bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
* ```
*
* Roles can be used to represent a set of permissions. To restrict access to a
* function call, use {hasRole}:
*
* ```
* function foo() public {
* require(hasRole(MY_ROLE, msg.sender));
* ...
* }
* ```
*
* Roles can be granted and revoked dynamically via the {grantRole} and
* {revokeRole} functions. Each role has an associated admin role, and only
* accounts that have a role's admin role can call {grantRole} and {revokeRole}.
*
* By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
* that only accounts with this role will be able to grant or revoke other
* roles. More complex role relationships can be created by using
* {_setRoleAdmin}.
*
* WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
* grant and revoke this role. Extra precautions should be taken to secure
* accounts that have been granted it.
*/
abstract contract AccessControl is Context, IAccessControl, ERC165 {
struct RoleData {
mapping(address => bool) members;
bytes32 adminRole;
}
mapping(bytes32 => RoleData) private _roles;
bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
/**
* @dev Modifier that checks that an account has a specific role. Reverts
* with a standardized message including the required role.
*
* The format of the revert reason is given by the following regular expression:
*
* /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
*
* _Available since v4.1._
*/
modifier onlyRole(bytes32 role) {
_checkRole(role);
_;
}
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);
}
/**
* @dev Returns `true` if `account` has been granted `role`.
*/
function hasRole(bytes32 role, address account) public view virtual override returns (bool) {
return _roles[role].members[account];
}
/**
* @dev Revert with a standard message if `_msgSender()` is missing `role`.
* Overriding this function changes the behavior of the {onlyRole} modifier.
*
* Format of the revert message is described in {_checkRole}.
*
* _Available since v4.6._
*/
function _checkRole(bytes32 role) internal view virtual {
_checkRole(role, _msgSender());
}
/**
* @dev Revert with a standard message if `account` is missing `role`.
*
* The format of the revert reason is given by the following regular expression:
*
* /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
*/
function _checkRole(bytes32 role, address account) internal view virtual {
if (!hasRole(role, account)) {
revert(
string(
abi.encodePacked(
"AccessControl: account ",
Strings.toHexString(uint160(account), 20),
" is missing role ",
Strings.toHexString(uint256(role), 32)
)
)
);
}
}
/**
* @dev Returns the admin role that controls `role`. See {grantRole} and
* {revokeRole}.
*
* To change a role's admin, use {_setRoleAdmin}.
*/
function getRoleAdmin(bytes32 role) public view virtual override returns (bytes32) {
return _roles[role].adminRole;
}
/**
* @dev Grants `role` to `account`.
*
* If `account` had not been already granted `role`, emits a {RoleGranted}
* event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*
* May emit a {RoleGranted} event.
*/
function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
_grantRole(role, account);
}
/**
* @dev Revokes `role` from `account`.
*
* If `account` had been granted `role`, emits a {RoleRevoked} event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*
* May emit a {RoleRevoked} event.
*/
function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
_revokeRole(role, account);
}
/**
* @dev Revokes `role` from the calling account.
*
* Roles are often managed via {grantRole} and {revokeRole}: this function's
* purpose is to provide a mechanism for accounts to lose their privileges
* if they are compromised (such as when a trusted device is misplaced).
*
* If the calling account had been revoked `role`, emits a {RoleRevoked}
* event.
*
* Requirements:
*
* - the caller must be `account`.
*
* May emit a {RoleRevoked} event.
*/
function renounceRole(bytes32 role, address account) public virtual override {
require(account == _msgSender(), "AccessControl: can only renounce roles for self");
_revokeRole(role, account);
}
/**
* @dev Grants `role` to `account`.
*
* If `account` had not been already granted `role`, emits a {RoleGranted}
* event. Note that unlike {grantRole}, this function doesn't perform any
* checks on the calling account.
*
* May emit a {RoleGranted} event.
*
* [WARNING]
* ====
* This function should only be called from the constructor when setting
* up the initial roles for the system.
*
* Using this function in any other way is effectively circumventing the admin
* system imposed by {AccessControl}.
* ====
*
* NOTE: This function is deprecated in favor of {_grantRole}.
*/
function _setupRole(bytes32 role, address account) internal virtual {
_grantRole(role, account);
}
/**
* @dev Sets `adminRole` as ``role``'s admin role.
*
* Emits a {RoleAdminChanged} event.
*/
function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
bytes32 previousAdminRole = getRoleAdmin(role);
_roles[role].adminRole = adminRole;
emit RoleAdminChanged(role, previousAdminRole, adminRole);
}
/**
* @dev Grants `role` to `account`.
*
* Internal function without access restriction.
*
* May emit a {RoleGranted} event.
*/
function _grantRole(bytes32 role, address account) internal virtual {
if (!hasRole(role, account)) {
_roles[role].members[account] = true;
emit RoleGranted(role, account, _msgSender());
}
}
/**
* @dev Revokes `role` from `account`.
*
* Internal function without access restriction.
*
* May emit a {RoleRevoked} event.
*/
function _revokeRole(bytes32 role, address account) internal virtual {
if (hasRole(role, account)) {
_roles[role].members[account] = false;
emit RoleRevoked(role, account, _msgSender());
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)
pragma solidity ^0.8.0;
/**
* @dev External interface of AccessControl declared to support ERC165 detection.
*/
interface IAccessControl {
/**
* @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
*
* `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
* {RoleAdminChanged} not being emitted signaling this.
*
* _Available since v3.1._
*/
event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
/**
* @dev Emitted when `account` is granted `role`.
*
* `sender` is the account that originated the contract call, an admin role
* bearer except when using {AccessControl-_setupRole}.
*/
event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
/**
* @dev Emitted when `account` is revoked `role`.
*
* `sender` is the account that originated the contract call:
* - if using `revokeRole`, it is the admin role bearer
* - if using `renounceRole`, it is the role bearer (i.e. `account`)
*/
event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
/**
* @dev Returns `true` if `account` has been granted `role`.
*/
function hasRole(bytes32 role, address account) external view returns (bool);
/**
* @dev Returns the admin role that controls `role`. See {grantRole} and
* {revokeRole}.
*
* To change a role's admin, use {AccessControl-_setRoleAdmin}.
*/
function getRoleAdmin(bytes32 role) external view returns (bytes32);
/**
* @dev Grants `role` to `account`.
*
* If `account` had not been already granted `role`, emits a {RoleGranted}
* event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*/
function grantRole(bytes32 role, address account) external;
/**
* @dev Revokes `role` from `account`.
*
* If `account` had been granted `role`, emits a {RoleRevoked} event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*/
function revokeRole(bytes32 role, address account) external;
/**
* @dev Revokes `role` from the calling account.
*
* Roles are often managed via {grantRole} and {revokeRole}: this function's
* purpose is to provide a mechanism for accounts to lose their privileges
* if they are compromised (such as when a trusted device is misplaced).
*
* If the calling account had been granted `role`, emits a {RoleRevoked}
* event.
*
* Requirements:
*
* - the caller must be `account`.
*/
function renounceRole(bytes32 role, address account) external;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (governance/TimelockController.sol)
pragma solidity ^0.8.0;
import "../access/AccessControl.sol";
import "../token/ERC721/IERC721Receiver.sol";
import "../token/ERC1155/IERC1155Receiver.sol";
import "../utils/Address.sol";
/**
* @dev Contract module which acts as a timelocked controller. When set as the
* owner of an `Ownable` smart contract, it enforces a timelock on all
* `onlyOwner` maintenance operations. This gives time for users of the
* controlled contract to exit before a potentially dangerous maintenance
* operation is applied.
*
* By default, this contract is self administered, meaning administration tasks
* have to go through the timelock process. The proposer (resp executor) role
* is in charge of proposing (resp executing) operations. A common use case is
* to position this {TimelockController} as the owner of a smart contract, with
* a multisig or a DAO as the sole proposer.
*
* _Available since v3.3._
*/
contract TimelockController is AccessControl, IERC721Receiver, IERC1155Receiver {
bytes32 public constant TIMELOCK_ADMIN_ROLE = keccak256("TIMELOCK_ADMIN_ROLE");
bytes32 public constant PROPOSER_ROLE = keccak256("PROPOSER_ROLE");
bytes32 public constant EXECUTOR_ROLE = keccak256("EXECUTOR_ROLE");
bytes32 public constant CANCELLER_ROLE = keccak256("CANCELLER_ROLE");
uint256 internal constant _DONE_TIMESTAMP = uint256(1);
mapping(bytes32 => uint256) private _timestamps;
uint256 private _minDelay;
/**
* @dev Emitted when a call is scheduled as part of operation `id`.
*/
event CallScheduled(
bytes32 indexed id,
uint256 indexed index,
address target,
uint256 value,
bytes data,
bytes32 predecessor,
uint256 delay
);
/**
* @dev Emitted when a call is performed as part of operation `id`.
*/
event CallExecuted(bytes32 indexed id, uint256 indexed index, address target, uint256 value, bytes data);
/**
* @dev Emitted when operation `id` is cancelled.
*/
event Cancelled(bytes32 indexed id);
/**
* @dev Emitted when the minimum delay for future operations is modified.
*/
event MinDelayChange(uint256 oldDuration, uint256 newDuration);
/**
* @dev Initializes the contract with a given `minDelay`, and a list of
* initial proposers and executors. The proposers receive both the
* proposer and the canceller role (for backward compatibility). The
* executors receive the executor role.
*
* NOTE: At construction, both the deployer and the timelock itself are
* administrators. This helps further configuration of the timelock by the
* deployer. After configuration is done, it is recommended that the
* deployer renounces its admin position and relies on timelocked
* operations to perform future maintenance.
*/
constructor(
uint256 minDelay,
address[] memory proposers,
address[] memory executors
) {
_setRoleAdmin(TIMELOCK_ADMIN_ROLE, TIMELOCK_ADMIN_ROLE);
_setRoleAdmin(PROPOSER_ROLE, TIMELOCK_ADMIN_ROLE);
_setRoleAdmin(EXECUTOR_ROLE, TIMELOCK_ADMIN_ROLE);
_setRoleAdmin(CANCELLER_ROLE, TIMELOCK_ADMIN_ROLE);
// deployer + self administration
_setupRole(TIMELOCK_ADMIN_ROLE, _msgSender());
_setupRole(TIMELOCK_ADMIN_ROLE, address(this));
// register proposers and cancellers
for (uint256 i = 0; i < proposers.length; ++i) {
_setupRole(PROPOSER_ROLE, proposers[i]);
_setupRole(CANCELLER_ROLE, proposers[i]);
}
// register executors
for (uint256 i = 0; i < executors.length; ++i) {
_setupRole(EXECUTOR_ROLE, executors[i]);
}
_minDelay = minDelay;
emit MinDelayChange(0, minDelay);
}
/**
* @dev Modifier to make a function callable only by a certain role. In
* addition to checking the sender's role, `address(0)` 's role is also
* considered. Granting a role to `address(0)` is equivalent to enabling
* this role for everyone.
*/
modifier onlyRoleOrOpenRole(bytes32 role) {
if (!hasRole(role, address(0))) {
_checkRole(role, _msgSender());
}
_;
}
/**
* @dev Contract might receive/hold ETH as part of the maintenance process.
*/
receive() external payable {}
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, AccessControl) returns (bool) {
return interfaceId == type(IERC1155Receiver).interfaceId || super.supportsInterface(interfaceId);
}
/**
* @dev Returns whether an id correspond to a registered operation. This
* includes both Pending, Ready and Done operations.
*/
function isOperation(bytes32 id) public view virtual returns (bool registered) {
return getTimestamp(id) > 0;
}
/**
* @dev Returns whether an operation is pending or not.
*/
function isOperationPending(bytes32 id) public view virtual returns (bool pending) {
return getTimestamp(id) > _DONE_TIMESTAMP;
}
/**
* @dev Returns whether an operation is ready or not.
*/
function isOperationReady(bytes32 id) public view virtual returns (bool ready) {
uint256 timestamp = getTimestamp(id);
return timestamp > _DONE_TIMESTAMP && timestamp <= block.timestamp;
}
/**
* @dev Returns whether an operation is done or not.
*/
function isOperationDone(bytes32 id) public view virtual returns (bool done) {
return getTimestamp(id) == _DONE_TIMESTAMP;
}
/**
* @dev Returns the timestamp at with an operation becomes ready (0 for
* unset operations, 1 for done operations).
*/
function getTimestamp(bytes32 id) public view virtual returns (uint256 timestamp) {
return _timestamps[id];
}
/**
* @dev Returns the minimum delay for an operation to become valid.
*
* This value can be changed by executing an operation that calls `updateDelay`.
*/
function getMinDelay() public view virtual returns (uint256 duration) {
return _minDelay;
}
/**
* @dev Returns the identifier of an operation containing a single
* transaction.
*/
function hashOperation(
address target,
uint256 value,
bytes calldata data,
bytes32 predecessor,
bytes32 salt
) public pure virtual returns (bytes32 hash) {
return keccak256(abi.encode(target, value, data, predecessor, salt));
}
/**
* @dev Returns the identifier of an operation containing a batch of
* transactions.
*/
function hashOperationBatch(
address[] calldata targets,
uint256[] calldata values,
bytes[] calldata payloads,
bytes32 predecessor,
bytes32 salt
) public pure virtual returns (bytes32 hash) {
return keccak256(abi.encode(targets, values, payloads, predecessor, salt));
}
/**
* @dev Schedule an operation containing a single transaction.
*
* Emits a {CallScheduled} event.
*
* Requirements:
*
* - the caller must have the 'proposer' role.
*/
function schedule(
address target,
uint256 value,
bytes calldata data,
bytes32 predecessor,
bytes32 salt,
uint256 delay
) public virtual onlyRole(PROPOSER_ROLE) {
bytes32 id = hashOperation(target, value, data, predecessor, salt);
_schedule(id, delay);
emit CallScheduled(id, 0, target, value, data, predecessor, delay);
}
/**
* @dev Schedule an operation containing a batch of transactions.
*
* Emits one {CallScheduled} event per transaction in the batch.
*
* Requirements:
*
* - the caller must have the 'proposer' role.
*/
function scheduleBatch(
address[] calldata targets,
uint256[] calldata values,
bytes[] calldata payloads,
bytes32 predecessor,
bytes32 salt,
uint256 delay
) public virtual onlyRole(PROPOSER_ROLE) {
require(targets.length == values.length, "TimelockController: length mismatch");
require(targets.length == payloads.length, "TimelockController: length mismatch");
bytes32 id = hashOperationBatch(targets, values, payloads, predecessor, salt);
_schedule(id, delay);
for (uint256 i = 0; i < targets.length; ++i) {
emit CallScheduled(id, i, targets[i], values[i], payloads[i], predecessor, delay);
}
}
/**
* @dev Schedule an operation that is to becomes valid after a given delay.
*/
function _schedule(bytes32 id, uint256 delay) private {
require(!isOperation(id), "TimelockController: operation already scheduled");
require(delay >= getMinDelay(), "TimelockController: insufficient delay");
_timestamps[id] = block.timestamp + delay;
}
/**
* @dev Cancel an operation.
*
* Requirements:
*
* - the caller must have the 'canceller' role.
*/
function cancel(bytes32 id) public virtual onlyRole(CANCELLER_ROLE) {
require(isOperationPending(id), "TimelockController: operation cannot be cancelled");
delete _timestamps[id];
emit Cancelled(id);
}
/**
* @dev Execute an (ready) operation containing a single transaction.
*
* Emits a {CallExecuted} event.
*
* Requirements:
*
* - the caller must have the 'executor' role.
*/
// This function can reenter, but it doesn't pose a risk because _afterCall checks that the proposal is pending,
// thus any modifications to the operation during reentrancy should be caught.
// slither-disable-next-line reentrancy-eth
function execute(
address target,
uint256 value,
bytes calldata payload,
bytes32 predecessor,
bytes32 salt
) public payable virtual onlyRoleOrOpenRole(EXECUTOR_ROLE) {
bytes32 id = hashOperation(target, value, payload, predecessor, salt);
_beforeCall(id, predecessor);
_execute(target, value, payload);
emit CallExecuted(id, 0, target, value, payload);
_afterCall(id);
}
/**
* @dev Execute an (ready) operation containing a batch of transactions.
*
* Emits one {CallExecuted} event per transaction in the batch.
*
* Requirements:
*
* - the caller must have the 'executor' role.
*/
function executeBatch(
address[] calldata targets,
uint256[] calldata values,
bytes[] calldata payloads,
bytes32 predecessor,
bytes32 salt
) public payable virtual onlyRoleOrOpenRole(EXECUTOR_ROLE) {
require(targets.length == values.length, "TimelockController: length mismatch");
require(targets.length == payloads.length, "TimelockController: length mismatch");
bytes32 id = hashOperationBatch(targets, values, payloads, predecessor, salt);
_beforeCall(id, predecessor);
for (uint256 i = 0; i < targets.length; ++i) {
address target = targets[i];
uint256 value = values[i];
bytes calldata payload = payloads[i];
_execute(target, value, payload);
emit CallExecuted(id, i, target, value, payload);
}
_afterCall(id);
}
/**
* @dev Execute an operation's call.
*/
function _execute(
address target,
uint256 value,
bytes calldata data
) internal virtual {
(bool success, ) = target.call{value: value}(data);
require(success, "TimelockController: underlying transaction reverted");
}
/**
* @dev Checks before execution of an operation's calls.
*/
function _beforeCall(bytes32 id, bytes32 predecessor) private view {
require(isOperationReady(id), "TimelockController: operation is not ready");
require(predecessor == bytes32(0) || isOperationDone(predecessor), "TimelockController: missing dependency");
}
/**
* @dev Checks after execution of an operation's calls.
*/
function _afterCall(bytes32 id) private {
require(isOperationReady(id), "TimelockController: operation is not ready");
_timestamps[id] = _DONE_TIMESTAMP;
}
/**
* @dev Changes the minimum timelock duration for future operations.
*
* Emits a {MinDelayChange} event.
*
* Requirements:
*
* - the caller must be the timelock itself. This can only be achieved by scheduling and later executing
* an operation where the timelock is the target and the data is the ABI-encoded call to this function.
*/
function updateDelay(uint256 newDelay) external virtual {
require(msg.sender == address(this), "TimelockController: caller must be timelock");
emit MinDelayChange(_minDelay, newDelay);
_minDelay = newDelay;
}
/**
* @dev See {IERC721Receiver-onERC721Received}.
*/
function onERC721Received(
address,
address,
uint256,
bytes memory
) public virtual override returns (bytes4) {
return this.onERC721Received.selector;
}
/**
* @dev See {IERC1155Receiver-onERC1155Received}.
*/
function onERC1155Received(
address,
address,
uint256,
uint256,
bytes memory
) public virtual override returns (bytes4) {
return this.onERC1155Received.selector;
}
/**
* @dev See {IERC1155Receiver-onERC1155BatchReceived}.
*/
function onERC1155BatchReceived(
address,
address,
uint256[] memory,
uint256[] memory,
bytes memory
) public virtual override returns (bytes4) {
return this.onERC1155BatchReceived.selector;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (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.
*
* NOTE: 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.
*
* NOTE: 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 (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)
pragma solidity ^0.8.0;
/**
* @title ERC721 token receiver interface
* @dev Interface for any contract that wants to support safeTransfers
* from ERC721 asset contracts.
*/
interface IERC721Receiver {
/**
* @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
* by `operator` from `from`, this function is called.
*
* It must return its Solidity selector to confirm the token transfer.
* If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
*
* The selector can be obtained in Solidity with `IERC721Receiver.onERC721Received.selector`.
*/
function onERC721Received(
address operator,
address from,
uint256 tokenId,
bytes calldata data
) external returns (bytes4);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
pragma solidity ^0.8.1;
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*
* [IMPORTANT]
* ====
* You shouldn't rely on `isContract` to protect against flash loan attacks!
*
* Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
* like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
* constructor.
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize/address.code.length, which returns 0
// for contracts in construction, since the code is only stored at the end
// of the constructor execution.
return account.code.length > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value
) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
(bool success, bytes memory returndata) = target.call{value: value}(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(
address target,
bytes memory data,
string memory errorMessage
) internal view returns (bytes memory) {
require(isContract(target), "Address: static call to non-contract");
(bool success, bytes memory returndata) = target.staticcall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
require(isContract(target), "Address: delegate call to non-contract");
(bool success, bytes memory returndata) = target.delegatecall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason using the provided one.
*
* _Available since v4.3._
*/
function verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) internal pure returns (bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
/// @solidity memory-safe-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/Context.sol)
pragma solidity ^0.8.0;
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
pragma solidity ^0.8.0;
import "./IERC165.sol";
/**
* @dev Implementation of the {IERC165} interface.
*
* Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
* for the additional interface id that will be supported. For example:
*
* ```solidity
* function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
* return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
* }
* ```
*
* Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
*/
abstract contract ERC165 is IERC165 {
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
return interfaceId == type(IERC165).interfaceId;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC165 standard, as defined in the
* https://eips.ethereum.org/EIPS/eip-165[EIP].
*
* Implementers can declare support of contract interfaces, which can then be
* queried by others ({ERC165Checker}).
*
* For an implementation, see {ERC165}.
*/
interface IERC165 {
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
* to learn more about how these ids are created.
*
* This function call must use less than 30 000 gas.
*/
function supportsInterface(bytes4 interfaceId) external view returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Strings.sol)
pragma solidity ^0.8.0;
/**
* @dev String operations.
*/
library Strings {
bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
uint8 private constant _ADDRESS_LENGTH = 20;
/**
* @dev Converts a `uint256` to its ASCII `string` decimal representation.
*/
function toString(uint256 value) internal pure returns (string memory) {
// Inspired by OraclizeAPI's implementation - MIT licence
// https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
if (value == 0) {
return "0";
}
uint256 temp = value;
uint256 digits;
while (temp != 0) {
digits++;
temp /= 10;
}
bytes memory buffer = new bytes(digits);
while (value != 0) {
digits -= 1;
buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
value /= 10;
}
return string(buffer);
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
*/
function toHexString(uint256 value) internal pure returns (string memory) {
if (value == 0) {
return "0x00";
}
uint256 temp = value;
uint256 length = 0;
while (temp != 0) {
length++;
temp >>= 8;
}
return toHexString(value, length);
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
*/
function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
bytes memory buffer = new bytes(2 * length + 2);
buffer[0] = "0";
buffer[1] = "x";
for (uint256 i = 2 * length + 1; i > 1; --i) {
buffer[i] = _HEX_SYMBOLS[value & 0xf];
value >>= 4;
}
require(value == 0, "Strings: hex length insufficient");
return string(buffer);
}
/**
* @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
*/
function toHexString(address addr) internal pure returns (string memory) {
return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
}
}