Contract Name:
MantaMintableERC20
Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import { IERC165 } from "@openzeppelin/contracts/utils/introspection/IERC165.sol";
/// @title IOptimismMintableERC20
/// @notice This interface is available on the OptimismMintableERC20 contract.
/// We declare it as a separate interface so that it can be used in
/// custom implementations of OptimismMintableERC20.
interface IOptimismMintableERC20 is IERC165 {
function remoteToken() external view returns (address);
function bridge() external returns (address);
function mint(address _to, uint256 _amount) external;
function burn(address _from, uint256 _amount) external;
}
/// @custom:legacy
/// @title ILegacyMintableERC20
/// @notice This interface was available on the legacy L2StandardERC20 contract.
/// It remains available on the OptimismMintableERC20 contract for
/// backwards compatibility.
interface ILegacyMintableERC20 is IERC165 {
function l1Token() external view returns (address);
function mint(address _to, uint256 _amount) external;
function burn(address _from, uint256 _amount) external;
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.15;
import { ERC20 } from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import { IERC165 } from "@openzeppelin/contracts/utils/introspection/IERC165.sol";
import { ILegacyMintableERC20, IOptimismMintableERC20 } from "./IOptimismMintableERC20.sol";
import { Semver } from "../universal/Semver.sol";
/// @title OptimismMintableERC20
/// @notice OptimismMintableERC20 is a standard extension of the base ERC20 token contract designed
/// to allow the StandardBridge contracts to mint and burn tokens. This makes it possible to
/// use an OptimismMintablERC20 as the L2 representation of an L1 token, or vice-versa.
/// Designed to be backwards compatible with the older StandardL2ERC20 token which was only
/// meant for use on L2.
contract OptimismMintableERC20 is IOptimismMintableERC20, ILegacyMintableERC20, ERC20, Semver {
/// @notice Address of the corresponding version of this token on the remote chain.
address public immutable REMOTE_TOKEN;
/// @notice Address of the StandardBridge on this network.
address public immutable BRIDGE;
/// @notice Decimals of the token
uint8 private immutable DECIMALS;
/// @notice Emitted whenever tokens are minted for an account.
/// @param account Address of the account tokens are being minted for.
/// @param amount Amount of tokens minted.
event Mint(address indexed account, uint256 amount);
/// @notice Emitted whenever tokens are burned from an account.
/// @param account Address of the account tokens are being burned from.
/// @param amount Amount of tokens burned.
event Burn(address indexed account, uint256 amount);
/// @notice A modifier that only allows the bridge to call
modifier onlyBridge() {
require(msg.sender == BRIDGE, "OptimismMintableERC20: only bridge can mint and burn");
_;
}
/// @custom:semver 1.2.0
/// @param _bridge Address of the L2 standard bridge.
/// @param _remoteToken Address of the corresponding L1 token.
/// @param _name ERC20 name.
/// @param _symbol ERC20 symbol.
constructor(
address _bridge,
address _remoteToken,
string memory _name,
string memory _symbol,
uint8 _decimals
)
ERC20(_name, _symbol)
Semver(1, 2, 0)
{
REMOTE_TOKEN = _remoteToken;
BRIDGE = _bridge;
DECIMALS = _decimals;
}
/// @notice Allows the StandardBridge on this network to mint tokens.
/// @param _to Address to mint tokens to.
/// @param _amount Amount of tokens to mint.
function mint(
address _to,
uint256 _amount
)
external
virtual
override(IOptimismMintableERC20, ILegacyMintableERC20)
onlyBridge
{
_mint(_to, _amount);
emit Mint(_to, _amount);
}
/// @notice Allows the StandardBridge on this network to burn tokens.
/// @param _from Address to burn tokens from.
/// @param _amount Amount of tokens to burn.
function burn(
address _from,
uint256 _amount
)
external
virtual
override(IOptimismMintableERC20, ILegacyMintableERC20)
onlyBridge
{
_burn(_from, _amount);
emit Burn(_from, _amount);
}
/// @notice ERC165 interface check function.
/// @param _interfaceId Interface ID to check.
/// @return Whether or not the interface is supported by this contract.
function supportsInterface(bytes4 _interfaceId) external pure virtual returns (bool) {
bytes4 iface1 = type(IERC165).interfaceId;
// Interface corresponding to the legacy L2StandardERC20.
bytes4 iface2 = type(ILegacyMintableERC20).interfaceId;
// Interface corresponding to the updated OptimismMintableERC20 (this contract).
bytes4 iface3 = type(IOptimismMintableERC20).interfaceId;
return _interfaceId == iface1 || _interfaceId == iface2 || _interfaceId == iface3;
}
/// @custom:legacy
/// @notice Legacy getter for the remote token. Use REMOTE_TOKEN going forward.
function l1Token() public view returns (address) {
return REMOTE_TOKEN;
}
/// @custom:legacy
/// @notice Legacy getter for the bridge. Use BRIDGE going forward.
function l2Bridge() public view returns (address) {
return BRIDGE;
}
/// @custom:legacy
/// @notice Legacy getter for REMOTE_TOKEN.
function remoteToken() public view returns (address) {
return REMOTE_TOKEN;
}
/// @custom:legacy
/// @notice Legacy getter for BRIDGE.
function bridge() public view returns (address) {
return BRIDGE;
}
/// @dev Returns the number of decimals used to get its user representation.
/// For example, if `decimals` equals `2`, a balance of `505` tokens should
/// be displayed to a user as `5.05` (`505 / 10 ** 2`).
/// NOTE: This information is only used for _display_ purposes: it in
/// no way affects any of the arithmetic of the contract, including
/// {IERC20-balanceOf} and {IERC20-transfer}.
function decimals() public view override returns (uint8) {
return DECIMALS;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import { Strings } from "@openzeppelin/contracts/utils/Strings.sol";
/// @title Semver
/// @notice Semver is a simple contract for managing contract versions.
contract Semver {
/// @notice Contract version number (major).
uint256 private immutable MAJOR_VERSION;
/// @notice Contract version number (minor).
uint256 private immutable MINOR_VERSION;
/// @notice Contract version number (patch).
uint256 private immutable PATCH_VERSION;
/// @param _major Version number (major).
/// @param _minor Version number (minor).
/// @param _patch Version number (patch).
constructor(uint256 _major, uint256 _minor, uint256 _patch) {
MAJOR_VERSION = _major;
MINOR_VERSION = _minor;
PATCH_VERSION = _patch;
}
/// @notice Returns the full semver contract version.
/// @return Semver contract version as a string.
function version() public view returns (string memory) {
return string(
abi.encodePacked(
Strings.toString(MAJOR_VERSION),
".",
Strings.toString(MINOR_VERSION),
".",
Strings.toString(PATCH_VERSION)
)
);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./IERC20.sol";
import "./extensions/IERC20Metadata.sol";
import "../../utils/Context.sol";
/**
* @dev Implementation of the {IERC20} interface.
*
* This implementation is agnostic to the way tokens are created. This means
* that a supply mechanism has to be added in a derived contract using {_mint}.
* For a generic mechanism see {ERC20PresetMinterPauser}.
*
* TIP: For a detailed writeup see our guide
* https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
* to implement supply mechanisms].
*
* We have followed general OpenZeppelin Contracts guidelines: functions revert
* instead returning `false` on failure. This behavior is nonetheless
* conventional and does not conflict with the expectations of ERC20
* applications.
*
* Additionally, an {Approval} event is emitted on calls to {transferFrom}.
* This allows applications to reconstruct the allowance for all accounts just
* by listening to said events. Other implementations of the EIP may not emit
* these events, as it isn't required by the specification.
*
* Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
* functions have been added to mitigate the well-known issues around setting
* allowances. See {IERC20-approve}.
*/
contract ERC20 is Context, IERC20, IERC20Metadata {
mapping(address => uint256) private _balances;
mapping(address => mapping(address => uint256)) private _allowances;
uint256 private _totalSupply;
string private _name;
string private _symbol;
/**
* @dev Sets the values for {name} and {symbol}.
*
* The default value of {decimals} is 18. To select a different value for
* {decimals} you should overload it.
*
* All two of these values are immutable: they can only be set once during
* construction.
*/
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
}
/**
* @dev Returns the name of the token.
*/
function name() public view virtual override returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view virtual override returns (string memory) {
return _symbol;
}
/**
* @dev Returns the number of decimals used to get its user representation.
* For example, if `decimals` equals `2`, a balance of `505` tokens should
* be displayed to a user as `5.05` (`505 / 10 ** 2`).
*
* Tokens usually opt for a value of 18, imitating the relationship between
* Ether and Wei. This is the value {ERC20} uses, unless this function is
* overridden;
*
* NOTE: This information is only used for _display_ purposes: it in
* no way affects any of the arithmetic of the contract, including
* {IERC20-balanceOf} and {IERC20-transfer}.
*/
function decimals() public view virtual override returns (uint8) {
return 18;
}
/**
* @dev See {IERC20-totalSupply}.
*/
function totalSupply() public view virtual override returns (uint256) {
return _totalSupply;
}
/**
* @dev See {IERC20-balanceOf}.
*/
function balanceOf(address account) public view virtual override returns (uint256) {
return _balances[account];
}
/**
* @dev See {IERC20-transfer}.
*
* Requirements:
*
* - `recipient` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/
function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
_transfer(_msgSender(), recipient, amount);
return true;
}
/**
* @dev See {IERC20-allowance}.
*/
function allowance(address owner, address spender) public view virtual override returns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See {IERC20-approve}.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 amount) public virtual override returns (bool) {
_approve(_msgSender(), spender, amount);
return true;
}
/**
* @dev See {IERC20-transferFrom}.
*
* Emits an {Approval} event indicating the updated allowance. This is not
* required by the EIP. See the note at the beginning of {ERC20}.
*
* Requirements:
*
* - `sender` and `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `amount`.
* - the caller must have allowance for ``sender``'s tokens of at least
* `amount`.
*/
function transferFrom(
address sender,
address recipient,
uint256 amount
) public virtual override returns (bool) {
_transfer(sender, recipient, amount);
uint256 currentAllowance = _allowances[sender][_msgSender()];
require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
unchecked {
_approve(sender, _msgSender(), currentAllowance - amount);
}
return true;
}
/**
* @dev Atomically increases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
_approve(_msgSender(), spender, _allowances[_msgSender()][spender] + addedValue);
return true;
}
/**
* @dev Atomically decreases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `spender` must have allowance for the caller of at least
* `subtractedValue`.
*/
function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
uint256 currentAllowance = _allowances[_msgSender()][spender];
require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
unchecked {
_approve(_msgSender(), spender, currentAllowance - subtractedValue);
}
return true;
}
/**
* @dev Moves `amount` of tokens from `sender` to `recipient`.
*
* This internal function is equivalent to {transfer}, and can be used to
* e.g. implement automatic token fees, slashing mechanisms, etc.
*
* Emits a {Transfer} event.
*
* Requirements:
*
* - `sender` cannot be the zero address.
* - `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `amount`.
*/
function _transfer(
address sender,
address recipient,
uint256 amount
) internal virtual {
require(sender != address(0), "ERC20: transfer from the zero address");
require(recipient != address(0), "ERC20: transfer to the zero address");
_beforeTokenTransfer(sender, recipient, amount);
uint256 senderBalance = _balances[sender];
require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
unchecked {
_balances[sender] = senderBalance - amount;
}
_balances[recipient] += amount;
emit Transfer(sender, recipient, amount);
_afterTokenTransfer(sender, recipient, amount);
}
/** @dev Creates `amount` tokens and assigns them to `account`, increasing
* the total supply.
*
* Emits a {Transfer} event with `from` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
*/
function _mint(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: mint to the zero address");
_beforeTokenTransfer(address(0), account, amount);
_totalSupply += amount;
_balances[account] += amount;
emit Transfer(address(0), account, amount);
_afterTokenTransfer(address(0), account, amount);
}
/**
* @dev Destroys `amount` tokens from `account`, reducing the
* total supply.
*
* Emits a {Transfer} event with `to` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
* - `account` must have at least `amount` tokens.
*/
function _burn(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: burn from the zero address");
_beforeTokenTransfer(account, address(0), amount);
uint256 accountBalance = _balances[account];
require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
unchecked {
_balances[account] = accountBalance - amount;
}
_totalSupply -= amount;
emit Transfer(account, address(0), amount);
_afterTokenTransfer(account, address(0), amount);
}
/**
* @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
*
* This internal function is equivalent to `approve`, and can be used to
* e.g. set automatic allowances for certain subsystems, etc.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `owner` cannot be the zero address.
* - `spender` cannot be the zero address.
*/
function _approve(
address owner,
address spender,
uint256 amount
) internal virtual {
require(owner != address(0), "ERC20: approve from the zero address");
require(spender != address(0), "ERC20: approve to the zero address");
_allowances[owner][spender] = amount;
emit Approval(owner, spender, amount);
}
/**
* @dev Hook that is called before any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* will be transferred to `to`.
* - when `from` is zero, `amount` tokens will be minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens will be burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _beforeTokenTransfer(
address from,
address to,
uint256 amount
) internal virtual {}
/**
* @dev Hook that is called after any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* has been transferred to `to`.
* - when `from` is zero, `amount` tokens have been minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens have been burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _afterTokenTransfer(
address from,
address to,
uint256 amount
) internal virtual {}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "../IERC20.sol";
/**
* @dev Interface for the optional metadata functions from the ERC20 standard.
*
* _Available since v4.1._
*/
interface IERC20Metadata is IERC20 {
/**
* @dev Returns the name of the token.
*/
function name() external view returns (string memory);
/**
* @dev Returns the symbol of the token.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the decimals places of the token.
*/
function decimals() external view returns (uint8);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address recipient, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `sender` to `recipient` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(
address sender,
address recipient,
uint256 amount
) external returns (bool);
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: MIT
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
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
pragma solidity ^0.8.0;
/**
* @dev String operations.
*/
library Strings {
bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
/**
* @dev Converts a `uint256` to its ASCII `string` decimal representation.
*/
function toString(uint256 value) internal pure returns (string memory) {
// Inspired by OraclizeAPI's implementation - MIT licence
// https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
if (value == 0) {
return "0";
}
uint256 temp = value;
uint256 digits;
while (temp != 0) {
digits++;
temp /= 10;
}
bytes memory buffer = new bytes(digits);
while (value != 0) {
digits -= 1;
buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
value /= 10;
}
return string(buffer);
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
*/
function toHexString(uint256 value) internal pure returns (string memory) {
if (value == 0) {
return "0x00";
}
uint256 temp = value;
uint256 length = 0;
while (temp != 0) {
length++;
temp >>= 8;
}
return toHexString(value, length);
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
*/
function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
bytes memory buffer = new bytes(2 * length + 2);
buffer[0] = "0";
buffer[1] = "x";
for (uint256 i = 2 * length + 1; i > 1; --i) {
buffer[i] = _HEX_SYMBOLS[value & 0xf];
value >>= 4;
}
require(value == 0, "Strings: hex length insufficient");
return string(buffer);
}
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.15;
import {OptimismMintableERC20} from "@eth-optimism/contracts-bedrock/src/universal/OptimismMintableERC20.sol";
contract MantaMintableERC20 is OptimismMintableERC20 {
constructor(
address _bridge,
address _remoteToken,
string memory _name,
string memory _symbol,
uint8 _decimals
) OptimismMintableERC20(_bridge, _remoteToken, _name, _symbol, _decimals) {}
}