Contract Source Code:
// 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 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
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: GPL-3.0
pragma solidity 0.8.9;
import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import { Context } from "@openzeppelin/contracts/utils/Context.sol";
import { Address } from "@openzeppelin/contracts/utils/Address.sol";
import "./interfaces/IUpgradeAgent.sol";
contract MystToken is Context, IERC20, IUpgradeAgent {
using Address for address;
address immutable _originalToken; // Address of MYSTv1 token
uint256 immutable _originalSupply; // Token supply of MYSTv1 token
// The original MYST token and the new MYST token have a decimal difference of 10.
// As such, minted values as well as the total supply comparisons need to offset all values
// by 10 zeros to properly compare them.
uint256 constant private DECIMAL_OFFSET = 1e10;
bool constant public override isUpgradeAgent = true; // Upgradeability interface marker
address private _upgradeMaster; // He can enable future token migration
IUpgradeAgent private _upgradeAgent; // The next contract where the tokens will be migrated
uint256 private _totalUpgraded; // How many tokens we have upgraded by now
mapping(address => uint256) private _balances;
uint256 private _totalSupply;
string constant public name = "Mysterium";
string constant public symbol = "MYST";
uint8 constant public decimals = 18;
// EIP712
bytes32 public DOMAIN_SEPARATOR;
// keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
// The nonces mapping is given for replay protection in permit function.
mapping(address => uint) public nonces;
// ERC20-allowances
mapping (address => mapping (address => uint256)) private _allowances;
event Minted(address indexed to, uint256 amount);
event Burned(address indexed from, uint256 amount);
// State of token upgrade
enum UpgradeState {Unknown, NotAllowed, WaitingForAgent, ReadyToUpgrade, Upgrading, Completed}
// Token upgrade events
event Upgrade(address indexed from, address agent, uint256 _value);
event UpgradeAgentSet(address agent);
event UpgradeMasterSet(address master);
constructor(address tokenAddress) {
// upgradability settings
_originalToken = tokenAddress;
_originalSupply = IERC20(tokenAddress).totalSupply();
// set upgrade master
_upgradeMaster = _msgSender();
// construct EIP712 domain separator
DOMAIN_SEPARATOR = keccak256(
abi.encode(
keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)'),
keccak256(bytes(name)),
keccak256(bytes('1')),
_chainID(),
address(this)
)
);
}
function totalSupply() public view override(IERC20) returns (uint256) {
return _totalSupply;
}
function balanceOf(address tokenHolder) public view override(IERC20) returns (uint256) {
return _balances[tokenHolder];
}
function transfer(address recipient, uint256 amount) public override returns (bool) {
_move(_msgSender(), recipient, amount);
return true;
}
function burn(uint256 amount) public {
_burn(_msgSender(), amount);
}
function allowance(address holder, address spender) public view override returns (uint256) {
return _allowances[holder][spender];
}
function approve(address spender, uint256 value) public override returns (bool) {
_approve(_msgSender(), spender, value);
return true;
}
function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
_approve(_msgSender(), spender, _allowances[_msgSender()][spender] + addedValue);
return true;
}
function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
_approve(_msgSender(), spender, _allowances[_msgSender()][spender] - subtractedValue);
return true;
}
/**
* ERC2612 `permit`: 712-signed token approvals
*/
function permit(address holder, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) external {
require(deadline >= block.timestamp, 'MYST: Permit expired');
bytes32 digest = keccak256(
abi.encodePacked(
'\x19\x01',
DOMAIN_SEPARATOR,
keccak256(abi.encode(PERMIT_TYPEHASH, holder, spender, value, nonces[holder]++, deadline))
)
);
address recoveredAddress = ecrecover(digest, v, r, s);
require(recoveredAddress != address(0) && recoveredAddress == holder, 'MYST: invalid signature');
_approve(holder, spender, value);
}
/**
* Note that we're not decreasing allowance of uint(-1). This makes it simple to ERC777 operator.
*/
function transferFrom(address holder, address recipient, uint256 amount) public override returns (bool) {
// require(recipient != address(0), "MYST: transfer to the zero address");
require(holder != address(0), "MYST: transfer from the zero address");
address spender = _msgSender();
// Allowance for uint256(-1) means "always allowed" and is analog for erc777 operators but in erc20 semantics.
if (holder != spender && _allowances[holder][spender] != type(uint256).max) {
_approve(holder, spender, _allowances[holder][spender] - amount);
}
_move(holder, recipient, amount);
return true;
}
/**
* Creates `amount` tokens and assigns them to `holder`, increasing
* the total supply.
*/
function _mint(address holder, uint256 amount) internal {
require(holder != address(0), "MYST: mint to the zero address");
// Update state variables
_totalSupply = _totalSupply + amount;
_balances[holder] = _balances[holder] + amount;
emit Minted(holder, amount);
emit Transfer(address(0), holder, amount);
}
function _burn(address from, uint256 amount) internal {
require(from != address(0), "MYST: burn from the zero address");
// Update state variables
_balances[from] = _balances[from] - amount;
_totalSupply = _totalSupply - amount;
emit Transfer(from, address(0), amount);
emit Burned(from, amount);
}
function _move(address from, address to, uint256 amount) private {
// Sending to zero address is equal burning
if (to == address(0)) {
_burn(from, amount);
return;
}
_balances[from] = _balances[from] - amount;
_balances[to] = _balances[to] + amount;
emit Transfer(from, to, amount);
}
function _approve(address holder, address spender, uint256 value) internal {
require(holder != address(0), "MYST: approve from the zero address");
require(spender != address(0), "MYST: approve to the zero address");
_allowances[holder][spender] = value;
emit Approval(holder, spender, value);
}
// -------------- UPGRADE FROM v1 TOKEN --------------
function originalToken() public view override returns (address) {
return _originalToken;
}
function originalSupply() public view override returns (uint256) {
return _originalSupply;
}
function upgradeFrom(address _account, uint256 _value) public override {
require(msg.sender == originalToken(), "only original token can call upgradeFrom");
// Value is multiplied by 0e10 as old token had decimals = 8?
_mint(_account, _value * DECIMAL_OFFSET);
require(totalSupply() <= originalSupply() * DECIMAL_OFFSET, "can not mint more tokens than in original contract");
}
// -------------- PREPARE FOR FUTURE UPGRADABILITY --------------
function upgradeMaster() public view returns (address) {
return _upgradeMaster;
}
function upgradeAgent() public view returns (address) {
return address(_upgradeAgent);
}
function totalUpgraded() public view returns (uint256) {
return _totalUpgraded;
}
/**
* Tokens can be upgraded by calling this function.
*/
function upgrade(uint256 amount) public {
UpgradeState state = getUpgradeState();
require(state == UpgradeState.ReadyToUpgrade || state == UpgradeState.Upgrading, "MYST: token is not in upgrading state");
require(amount != 0, "MYST: upgradable amount should be more than 0");
address holder = _msgSender();
// Burn tokens to be upgraded
_burn(holder, amount);
// Remember how many tokens we have upgraded
_totalUpgraded = _totalUpgraded + amount;
// Upgrade agent upgrades/reissues tokens
_upgradeAgent.upgradeFrom(holder, amount);
emit Upgrade(holder, upgradeAgent(), amount);
}
function setUpgradeMaster(address newUpgradeMaster) external {
require(newUpgradeMaster != address(0x0), "MYST: upgrade master can't be zero address");
require(_msgSender() == _upgradeMaster, "MYST: only upgrade master can set new one");
_upgradeMaster = newUpgradeMaster;
emit UpgradeMasterSet(upgradeMaster());
}
function setUpgradeAgent(address agent) external {
require(_msgSender()== _upgradeMaster, "MYST: only a master can designate the next agent");
require(agent != address(0x0), "MYST: upgrade agent can't be zero address");
require(getUpgradeState() != UpgradeState.Upgrading, "MYST: upgrade has already begun");
_upgradeAgent = IUpgradeAgent(agent);
require(_upgradeAgent.isUpgradeAgent(), "MYST: agent should implement IUpgradeAgent interface");
// Make sure that token supplies match in source and target
require(_upgradeAgent.originalSupply() == totalSupply(), "MYST: upgrade agent should know token's total supply");
emit UpgradeAgentSet(upgradeAgent());
}
function getUpgradeState() public view returns(UpgradeState) {
if(address(_upgradeAgent) == address(0x00)) return UpgradeState.WaitingForAgent;
else if(_totalUpgraded == 0) return UpgradeState.ReadyToUpgrade;
else if(totalSupply() == 0) return UpgradeState.Completed;
else return UpgradeState.Upgrading;
}
// -------------- FUNDS RECOVERY --------------
address internal _fundsDestination;
event FundsRecoveryDestinationChanged(address indexed previousDestination, address indexed newDestination);
/**
* Setting new destination of funds recovery.
*/
function setFundsDestination(address newDestination) public {
require(_msgSender()== _upgradeMaster, "MYST: only a master can set funds destination");
require(newDestination != address(0), "MYST: funds destination can't be zero addreess");
_fundsDestination = newDestination;
emit FundsRecoveryDestinationChanged(_fundsDestination, newDestination);
}
/**
* Getting funds destination address.
*/
function getFundsDestination() public view returns (address) {
return _fundsDestination;
}
/**
Transfers selected tokens into `_fundsDestination` address.
*/
function claimTokens(address token) public {
require(_fundsDestination != address(0));
uint256 amount = IERC20(token).balanceOf(address(this));
IERC20(token).transfer(_fundsDestination, amount);
}
// -------------- HELPERS --------------
function _chainID() private view returns (uint256) {
uint256 chainID;
assembly {
chainID := chainid()
}
return chainID;
}
// -------------- TESTNET ONLY FUNCTIONS --------------
function mint(address _account, uint _amount) public {
require(_msgSender()== _upgradeMaster, "MYST: only a master can mint");
_mint(_account, _amount);
}
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.8.4;
/**
* Upgrade agent interface inspired by Lunyr.
*
* Upgrade agent transfers tokens to a new contract.
* Upgrade agent itself can be the token contract, or just a middle man contract doing the heavy lifting.
*/
abstract contract IUpgradeAgent {
function isUpgradeAgent() external virtual pure returns (bool);
function upgradeFrom(address _from, uint256 _value) public virtual;
function originalSupply() public virtual view returns (uint256);
function originalToken() public virtual view returns (address);
}