Contract Source Code:
/// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/token/ERC20/extensions/draft-ERC20Permit.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "../library/AddArrayLib.sol";
import "../interfaces/ITradeExecutor.sol";
import "../interfaces/IVault.sol";
/// @title vault (Brahma Vault)
/// @author 0xAd1 and Bapireddy
/// @notice Minimal vault contract to support trades across different protocols.
contract Vault is IVault, ERC20Permit, ReentrancyGuard {
using AddrArrayLib for AddrArrayLib.Addresses;
using SafeERC20 for IERC20;
/*///////////////////////////////////////////////////////////////
CONSTANTS
//////////////////////////////////////////////////////////////*/
/// @notice The maximum number of blocks for latest update to be valid.
/// @dev Needed for processing deposits/withdrawals.
uint256 constant BLOCK_LIMIT = 50;
/// @dev minimum balance used to check when executor is removed.
uint256 constant DUST_LIMIT = 10**6;
/// @dev The max basis points used as normalizing factor.
uint256 constant MAX_BPS = 10000;
/// @dev The max amount of seconds in year.
/// accounting for leap years there are 365.25 days in year.
/// 365.25 * 86400 = 31557600.0
uint256 constant MAX_SECONDS = 31557600;
/*///////////////////////////////////////////////////////////////
IMMUTABLES
//////////////////////////////////////////////////////////////*/
/// @notice The underlying token the vault accepts.
address public immutable override wantToken;
uint8 private immutable tokenDecimals;
/*///////////////////////////////////////////////////////////////
MUTABLE ACCESS MODFIERS
//////////////////////////////////////////////////////////////*/
/// @notice boolean for enabling deposit/withdraw solely via batcher.
bool public batcherOnlyDeposit;
/// @notice boolean for enabling emergency mode to halt new withdrawal/deposits into vault.
bool public emergencyMode;
// @notice address of batcher used for batching user deposits/withdrawals.
address public batcher;
/// @notice keeper address to move funds between executors.
address public override keeper;
/// @notice Governance address to add/remove executors.
address public override governance;
address public pendingGovernance;
/// @notice Creates a new Vault that accepts a specific underlying token.
/// @param _wantToken The ERC20 compliant token the vault should accept.
/// @param _name The name of the vault token.
/// @param _symbol The symbol of the vault token.
/// @param _keeper The address of the keeper to move funds between executors.
/// @param _governance The address of the governance to perform governance functions.
constructor(
string memory _name,
string memory _symbol,
address _wantToken,
address _keeper,
address _governance
) ERC20(_name, _symbol) ERC20Permit(_name) {
tokenDecimals = IERC20Metadata(_wantToken).decimals();
wantToken = _wantToken;
keeper = _keeper;
governance = _governance;
// to prevent any front running deposits
batcherOnlyDeposit = true;
}
function decimals() public view override returns (uint8) {
return tokenDecimals;
}
/*///////////////////////////////////////////////////////////////
USER DEPOSIT/WITHDRAWAL LOGIC
//////////////////////////////////////////////////////////////*/
/// @notice Initiates a deposit of want tokens to the vault.
/// @param amountIn The amount of want tokens to deposit.
/// @param receiver The address to receive vault tokens.
function deposit(uint256 amountIn, address receiver)
public
override
nonReentrant
ensureFeesAreCollected
returns (uint256 shares)
{
/// checks for only batcher deposit
onlyBatcher();
isValidAddress(receiver);
require(amountIn > 0, "ZERO_AMOUNT");
// calculate the shares based on the amount.
shares = totalSupply() > 0
? (totalSupply() * amountIn) / totalVaultFunds()
: amountIn;
require(shares != 0, "ZERO_SHARES");
IERC20(wantToken).safeTransferFrom(msg.sender, address(this), amountIn);
_mint(receiver, shares);
}
/// @notice Initiates a withdrawal of vault tokens to the user.
/// @param sharesIn The amount of vault tokens to withdraw.
/// @param receiver The address to receive the vault tokens.
function withdraw(uint256 sharesIn, address receiver)
public
override
nonReentrant
ensureFeesAreCollected
returns (uint256 amountOut)
{
/// checks for only batcher withdrawal
onlyBatcher();
isValidAddress(receiver);
require(sharesIn > 0, "ZERO_SHARES");
// calculate the amount based on the shares.
amountOut = (sharesIn * totalVaultFunds()) / totalSupply();
// burn shares of msg.sender
_burn(msg.sender, sharesIn);
/// charging exitFee
if (exitFee > 0) {
uint256 fee = (amountOut * exitFee) / MAX_BPS;
IERC20(wantToken).transfer(governance, fee);
amountOut = amountOut - fee;
}
IERC20(wantToken).safeTransfer(receiver, amountOut);
}
/// @notice Calculates the total amount of underlying tokens the vault holds.
/// @return The total amount of underlying tokens the vault holds.
function totalVaultFunds() public view returns (uint256) {
return
IERC20(wantToken).balanceOf(address(this)) + totalExecutorFunds();
}
/*///////////////////////////////////////////////////////////////
EXECUTOR DEPOSIT/WITHDRAWAL LOGIC
//////////////////////////////////////////////////////////////*/
/// @notice list of trade executors connected to vault.
AddrArrayLib.Addresses tradeExecutorsList;
/// @notice Emitted after the vault deposits into a executor contract.
/// @param executor The executor that was deposited into.
/// @param underlyingAmount The amount of underlying tokens that were deposited.
event ExecutorDeposit(address indexed executor, uint256 underlyingAmount);
/// @notice Emitted after the vault withdraws funds from a executor contract.
/// @param executor The executor that was withdrawn from.
/// @param underlyingAmount The amount of underlying tokens that were withdrawn.
event ExecutorWithdrawal(
address indexed executor,
uint256 underlyingAmount
);
/// @notice Deposit given amount of want tokens into valid executor.
/// @param _executor The executor to deposit into.
/// @param _amount The amount of want tokens to deposit.
function depositIntoExecutor(address _executor, uint256 _amount)
public
nonReentrant
{
isActiveExecutor(_executor);
onlyKeeper();
require(_amount > 0, "ZERO_AMOUNT");
IERC20(wantToken).safeTransfer(_executor, _amount);
emit ExecutorDeposit(_executor, _amount);
}
/// @notice Withdraw given amount of want tokens into valid executor.
/// @param _executor The executor to withdraw tokens from.
/// @param _amount The amount of want tokens to withdraw.
function withdrawFromExecutor(address _executor, uint256 _amount)
public
nonReentrant
{
isActiveExecutor(_executor);
onlyKeeper();
require(_amount > 0, "ZERO_AMOUNT");
IERC20(wantToken).safeTransferFrom(_executor, address(this), _amount);
emit ExecutorWithdrawal(_executor, _amount);
}
/*///////////////////////////////////////////////////////////////
FEE CONFIGURATION
//////////////////////////////////////////////////////////////*/
/// @notice lagging value of vault total funds.
/// @dev value intialized to max to prevent slashing on first deposit.
uint256 public prevVaultFunds = type(uint256).max;
/// @dev value intialized to max to prevent slashing on first deposit.
uint256 public lastReportedTime = type(uint256).max;
/// @dev Perfomance fee for the vault.
uint256 public performanceFee;
/// @notice Fee denominated in MAX_BPS charged during exit.
uint256 public exitFee;
/// @notice Mangement fee for operating the vault.
uint256 public managementFee;
/// @notice Emitted after perfomance fee updation.
/// @param oldFee The old performance fee on vault.
/// @param newFee The new performance fee on vault.
event UpdatePerformanceFee(uint256 oldFee, uint256 newFee);
/// @notice Updates the performance fee on the vault.
/// @param _fee The new performance fee on the vault.
/// @dev The new fee must be always less than 50% of yield.
function setPerformanceFee(uint256 _fee) public {
onlyGovernance();
require(_fee < MAX_BPS / 2, "FEE_TOO_HIGH");
emit UpdatePerformanceFee(performanceFee, _fee);
performanceFee = _fee;
}
/// @notice Emitted after exit fee updation.
/// @param oldFee The old exit fee on vault.
/// @param newFee The new exit fee on vault.
event UpdateExitFee(uint256 oldFee, uint256 newFee);
/// @notice Function to set exit fee on the vault, can only be called by governance
/// @param _fee Address of fee
function setExitFee(uint256 _fee) public {
onlyGovernance();
require(_fee < MAX_BPS / 2, "EXIT_FEE_TOO_HIGH");
emit UpdateExitFee(exitFee, _fee);
exitFee = _fee;
}
/// @notice Emitted after management fee updation.
/// @param oldFee The old management fee on vault.
/// @param newFee The new management fee on vault.
event UpdateManagementFee(uint256 oldFee, uint256 newFee);
/// @notice Function to set exit fee on the vault, can only be called by governance
/// @param _fee Address of fee
function setManagementFee(uint256 _fee) public {
onlyGovernance();
require(_fee < MAX_BPS / 2, "EXIT_FEE_TOO_HIGH");
emit UpdateManagementFee(managementFee, _fee);
managementFee = _fee;
}
/// @notice Emitted when a fees are collected.
/// @param collectedFees The amount of fees collected.
event FeesCollected(uint256 collectedFees);
/// @notice Calculates and collects the fees from the vault.
/// @dev This function sends all the accured fees to governance.
/// checks the yield made since previous harvest and
/// calculates the fee based on it. Also note: this function
/// should be called before processing any new deposits/withdrawals.
function collectFees() internal {
uint256 currentFunds = totalVaultFunds();
uint256 fees = 0;
// collect fees only when profit is made.
if ((performanceFee > 0) && (currentFunds > prevVaultFunds)) {
uint256 yieldEarned = (currentFunds - prevVaultFunds);
// normalization by MAX_BPS
fees += ((yieldEarned * performanceFee) / MAX_BPS);
}
if ((managementFee > 0) && (lastReportedTime < block.timestamp)) {
uint256 duration = block.timestamp - lastReportedTime;
fees +=
((duration * managementFee * currentFunds) / MAX_SECONDS) /
MAX_BPS;
}
if (fees > 0) {
IERC20(wantToken).safeTransfer(governance, fees);
emit FeesCollected(fees);
}
}
modifier ensureFeesAreCollected() {
collectFees();
_;
// update vault funds after fees are collected.
prevVaultFunds = totalVaultFunds();
// update lastReportedTime after fees are collected.
lastReportedTime = block.timestamp;
}
/*///////////////////////////////////////////////////////////////
EXECUTOR ADDITION/REMOVAL LOGIC
//////////////////////////////////////////////////////////////*/
/// @notice Emitted when executor is added to vault.
/// @param executor The address of added executor.
event ExecutorAdded(address indexed executor);
/// @notice Emitted when executor is removed from vault.
/// @param executor The address of removed executor.
event ExecutorRemoved(address indexed executor);
/// @notice Adds a trade executor, enabling it to execute trades.
/// @param _tradeExecutor The address of _tradeExecutor contract.
function addExecutor(address _tradeExecutor) public {
onlyGovernance();
isValidAddress(_tradeExecutor);
require(
ITradeExecutor(_tradeExecutor).vault() == address(this),
"INVALID_VAULT"
);
require(
IERC20(wantToken).allowance(_tradeExecutor, address(this)) > 0,
"NO_ALLOWANCE"
);
tradeExecutorsList.pushAddress(_tradeExecutor);
emit ExecutorAdded(_tradeExecutor);
}
/// @notice Adds a trade executor, enabling it to execute trades.
/// @param _tradeExecutor The address of _tradeExecutor contract.
/// @dev make sure all funds are withdrawn from executor before removing.
function removeExecutor(address _tradeExecutor) public {
onlyGovernance();
isValidAddress(_tradeExecutor);
// check if executor attached to vault.
isActiveExecutor(_tradeExecutor);
(uint256 executorFunds, uint256 blockUpdated) = ITradeExecutor(
_tradeExecutor
).totalFunds();
areFundsUpdated(blockUpdated);
require(executorFunds < DUST_LIMIT, "FUNDS_TOO_HIGH");
tradeExecutorsList.removeAddress(_tradeExecutor);
emit ExecutorRemoved(_tradeExecutor);
}
/// @notice gives the number of trade executors.
/// @return The number of trade executors.
function totalExecutors() public view returns (uint256) {
return tradeExecutorsList.size();
}
/// @notice Returns trade executor at given index.
/// @return The executor address at given valid index.
function executorByIndex(uint256 _index) public view returns (address) {
return tradeExecutorsList.getAddressAtIndex(_index);
}
/// @notice Calculates funds held by all executors in want token.
/// @return Sum of all funds held by executors.
function totalExecutorFunds() public view returns (uint256) {
uint256 totalFunds = 0;
for (uint256 i = 0; i < totalExecutors(); i++) {
address executor = executorByIndex(i);
(uint256 executorFunds, uint256 blockUpdated) = ITradeExecutor(
executor
).totalFunds();
areFundsUpdated(blockUpdated);
totalFunds += executorFunds;
}
return totalFunds;
}
/*///////////////////////////////////////////////////////////////
GOVERNANCE ACTIONS
//////////////////////////////////////////////////////////////*/
/// @notice Emitted when a batcher is updated.
/// @param oldBatcher The address of the current batcher.
/// @param newBatcher The address of new batcher.
event UpdatedBatcher(
address indexed oldBatcher,
address indexed newBatcher
);
/// @notice Changes the batcher address.
/// @dev This can only be called by governance.
/// @param _batcher The address to for new batcher.
function setBatcher(address _batcher) public {
onlyGovernance();
emit UpdatedBatcher(batcher, _batcher);
batcher = _batcher;
}
/// @notice Emitted batcherOnlyDeposit is enabled.
/// @param state The state of depositing only via batcher.
event UpdatedBatcherOnlyDeposit(bool state);
/// @notice Enables/disables deposits with batcher only.
/// @dev This can only be called by governance.
/// @param _batcherOnlyDeposit if true vault can accept deposit via batcher only or else anyone can deposit.
function setBatcherOnlyDeposit(bool _batcherOnlyDeposit) public {
onlyGovernance();
batcherOnlyDeposit = _batcherOnlyDeposit;
emit UpdatedBatcherOnlyDeposit(_batcherOnlyDeposit);
}
/// @notice Nominates new governance address.
/// @dev Governance will only be changed if the new governance accepts it. It will be pending till then.
/// @param _governance The address of new governance.
function setGovernance(address _governance) public {
onlyGovernance();
pendingGovernance = _governance;
}
/// @notice Emitted when governance is updated.
/// @param oldGovernance The address of the current governance.
/// @param newGovernance The address of new governance.
event UpdatedGovernance(
address indexed oldGovernance,
address indexed newGovernance
);
/// @notice The nomine of new governance address proposed by `setGovernance` function can accept the governance.
/// @dev This can only be called by address of pendingGovernance.
function acceptGovernance() public {
require(msg.sender == pendingGovernance, "INVALID_ADDRESS");
emit UpdatedGovernance(governance, pendingGovernance);
governance = pendingGovernance;
}
/// @notice Emitted when keeper is updated.
/// @param oldKeeper The address of the old keeper.
/// @param newKeeper The address of the new keeper.
event UpdatedKeeper(address indexed oldKeeper, address indexed newKeeper);
/// @notice Sets new keeper address.
/// @dev This can only be called by governance.
/// @param _keeper The address of new keeper.
function setKeeper(address _keeper) public {
onlyGovernance();
emit UpdatedKeeper(keeper, _keeper);
keeper = _keeper;
}
/// @notice Emitted when emergencyMode status is updated.
/// @param emergencyMode boolean indicating state of emergency.
event EmergencyModeStatus(bool emergencyMode);
/// @notice sets emergencyMode.
/// @dev This can only be called by governance.
/// @param _emergencyMode if true, vault will be in emergency mode.
function setEmergencyMode(bool _emergencyMode) public {
onlyGovernance();
emergencyMode = _emergencyMode;
batcherOnlyDeposit = true;
batcher = address(0);
emit EmergencyModeStatus(_emergencyMode);
}
/// @notice Removes invalid tokens from the vault.
/// @dev This is used as fail safe to remove want tokens from the vault during emergency mode
/// can be called by anyone to send funds to governance.
/// @param _token The address of token to be removed.
function sweep(address _token) public {
isEmergencyMode();
IERC20(_token).safeTransfer(
governance,
IERC20(_token).balanceOf(address(this))
);
}
/*///////////////////////////////////////////////////////////////
ACCESS MODIFERS
//////////////////////////////////////////////////////////////*/
/// @dev Checks if the sender is the governance.
function onlyGovernance() internal view {
require(msg.sender == governance, "ONLY_GOV");
}
/// @dev Checks if the sender is the keeper.
function onlyKeeper() internal view {
require(msg.sender == keeper, "ONLY_KEEPER");
}
/// @dev Checks if the sender is the batcher.
function onlyBatcher() internal view {
if (batcherOnlyDeposit) {
require(msg.sender == batcher, "ONLY_BATCHER");
}
}
/// @dev Checks if emergency mode is enabled.
function isEmergencyMode() internal view {
require(emergencyMode == true, "EMERGENCY_MODE");
}
/// @dev Checks if the address is valid.
function isValidAddress(address _addr) internal pure {
require(_addr != address(0), "NULL_ADDRESS");
}
/// @dev Checks if the tradeExecutor is valid.
function isActiveExecutor(address _tradeExecutor) internal view {
require(tradeExecutorsList.exists(_tradeExecutor), "INVALID_EXECUTOR");
}
/// @dev Checks if funds are updated.
function areFundsUpdated(uint256 _blockUpdated) internal view {
require(
block.number <= _blockUpdated + BLOCK_LIMIT,
"FUNDS_NOT_UPDATED"
);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/extensions/draft-ERC20Permit.sol)
pragma solidity ^0.8.0;
import "./draft-IERC20Permit.sol";
import "../ERC20.sol";
import "../../../utils/cryptography/draft-EIP712.sol";
import "../../../utils/cryptography/ECDSA.sol";
import "../../../utils/Counters.sol";
/**
* @dev Implementation of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
* https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
*
* Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
* presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
* need to send a transaction, and thus is not required to hold Ether at all.
*
* _Available since v3.4._
*/
abstract contract ERC20Permit is ERC20, IERC20Permit, EIP712 {
using Counters for Counters.Counter;
mapping(address => Counters.Counter) private _nonces;
// solhint-disable-next-line var-name-mixedcase
bytes32 private constant _PERMIT_TYPEHASH =
keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
/**
* @dev In previous versions `_PERMIT_TYPEHASH` was declared as `immutable`.
* However, to ensure consistency with the upgradeable transpiler, we will continue
* to reserve a slot.
* @custom:oz-renamed-from _PERMIT_TYPEHASH
*/
// solhint-disable-next-line var-name-mixedcase
bytes32 private _PERMIT_TYPEHASH_DEPRECATED_SLOT;
/**
* @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`.
*
* It's a good idea to use the same `name` that is defined as the ERC20 token name.
*/
constructor(string memory name) EIP712(name, "1") {}
/**
* @dev See {IERC20Permit-permit}.
*/
function permit(
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) public virtual override {
require(block.timestamp <= deadline, "ERC20Permit: expired deadline");
bytes32 structHash = keccak256(abi.encode(_PERMIT_TYPEHASH, owner, spender, value, _useNonce(owner), deadline));
bytes32 hash = _hashTypedDataV4(structHash);
address signer = ECDSA.recover(hash, v, r, s);
require(signer == owner, "ERC20Permit: invalid signature");
_approve(owner, spender, value);
}
/**
* @dev See {IERC20Permit-nonces}.
*/
function nonces(address owner) public view virtual override returns (uint256) {
return _nonces[owner].current();
}
/**
* @dev See {IERC20Permit-DOMAIN_SEPARATOR}.
*/
// solhint-disable-next-line func-name-mixedcase
function DOMAIN_SEPARATOR() external view override returns (bytes32) {
return _domainSeparatorV4();
}
/**
* @dev "Consume a nonce": return the current value and increment.
*
* _Available since v4.1._
*/
function _useNonce(address owner) internal virtual returns (uint256 current) {
Counters.Counter storage nonce = _nonces[owner];
current = nonce.current();
nonce.increment();
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @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);
/**
* @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 `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, 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 `from` to `to` 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 from,
address to,
uint256 amount
) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
import "../../../utils/Address.sol";
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20 {
using Address for address;
function safeTransfer(
IERC20 token,
address to,
uint256 value
) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
function safeTransferFrom(
IERC20 token,
address from,
address to,
uint256 value
) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IERC20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
function safeApprove(
IERC20 token,
address spender,
uint256 value
) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
require(
(value == 0) || (token.allowance(address(this), spender) == 0),
"SafeERC20: approve from non-zero to non-zero allowance"
);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
function safeIncreaseAllowance(
IERC20 token,
address spender,
uint256 value
) internal {
uint256 newAllowance = token.allowance(address(this), spender) + value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
function safeDecreaseAllowance(
IERC20 token,
address spender,
uint256 value
) internal {
unchecked {
uint256 oldAllowance = token.allowance(address(this), spender);
require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
uint256 newAllowance = oldAllowance - value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function _callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
// the target address contains contract code and also asserts for success in the low-level call.
bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
if (returndata.length > 0) {
// Return data is optional
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
pragma solidity ^0.8.0;
/**
* @dev Contract module that helps prevent reentrant calls to a function.
*
* Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
* available, which can be applied to functions to make sure there are no nested
* (reentrant) calls to them.
*
* Note that because there is a single `nonReentrant` guard, functions marked as
* `nonReentrant` may not call one another. This can be worked around by making
* those functions `private`, and then adding `external` `nonReentrant` entry
* points to them.
*
* TIP: If you would like to learn more about reentrancy and alternative ways
* to protect against it, check out our blog post
* https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
*/
abstract contract ReentrancyGuard {
// Booleans are more expensive than uint256 or any type that takes up a full
// word because each write operation emits an extra SLOAD to first read the
// slot's contents, replace the bits taken up by the boolean, and then write
// back. This is the compiler's defense against contract upgrades and
// pointer aliasing, and it cannot be disabled.
// The values being non-zero value makes deployment a bit more expensive,
// but in exchange the refund on every call to nonReentrant will be lower in
// amount. Since refunds are capped to a percentage of the total
// transaction's gas, it is best to keep them low in cases like this one, to
// increase the likelihood of the full refund coming into effect.
uint256 private constant _NOT_ENTERED = 1;
uint256 private constant _ENTERED = 2;
uint256 private _status;
constructor() {
_status = _NOT_ENTERED;
}
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* Calling a `nonReentrant` function from another `nonReentrant`
* function is not supported. It is possible to prevent this from happening
* by making the `nonReentrant` function external, and making it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
// On the first call to nonReentrant, _notEntered will be true
require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
// Any calls to nonReentrant after this point will fail
_status = _ENTERED;
_;
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = _NOT_ENTERED;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
library AddrArrayLib {
using AddrArrayLib for Addresses;
struct Addresses {
address[] _items;
}
/**
* @notice push an address to the array
* @dev if the address already exists, it will not be added again
* @param self Storage array containing address type variables
* @param element the element to add in the array
*/
function pushAddress(Addresses storage self, address element) internal {
if (!exists(self, element)) {
self._items.push(element);
}
}
/**
* @notice remove an address from the array
* @dev finds the element, swaps it with the last element, and then deletes it;
* @param self Storage array containing address type variables
* @param element the element to remove from the array
*/
function removeAddress(Addresses storage self, address element) internal {
for (uint256 i = 0; i < self.size(); i++) {
if (self._items[i] == element) {
self._items[i] = self._items[self.size() - 1];
self._items.pop();
}
}
}
/**
* @notice get the address at a specific index from array
* @dev revert if the index is out of bounds
* @param self Storage array containing address type variables
* @param index the index in the array
*/
function getAddressAtIndex(Addresses memory self, uint256 index)
internal
view
returns (address)
{
require(index < size(self), "INVALID_INDEX");
return self._items[index];
}
/**
* @notice get the size of the array
* @param self Storage array containing address type variables
*/
function size(Addresses memory self) internal view returns (uint256) {
return self._items.length;
}
/**
* @notice check if an element exist in the array
* @param self Storage array containing address type variables
* @param element the element to check if it exists in the array
*/
function exists(Addresses memory self, address element)
internal
view
returns (bool)
{
for (uint256 i = 0; i < self.size(); i++) {
if (self._items[i] == element) {
return true;
}
}
return false;
}
/**
* @notice get the array
* @param self Storage array containing address type variables
*/
function getAllAddresses(Addresses memory self)
internal
view
returns (address[] memory)
{
return self._items;
}
}
//SPDX-License-Identifier: GPL-3.0-only
pragma solidity ^0.8.4;
interface ITradeExecutor {
struct ActionStatus {
bool inProcess;
address from;
}
function vault() external view returns (address);
function depositStatus() external returns (bool, address);
function withdrawalStatus() external returns (bool, address);
function initiateDeposit(bytes calldata _data) external;
function confirmDeposit() external;
function initiateWithdraw(bytes calldata _data) external;
function confirmWithdraw() external;
function totalFunds()
external
view
returns (uint256 posValue, uint256 lastUpdatedBlock);
}
/// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity ^0.8.0;
interface IVault {
function keeper() external view returns (address);
function governance() external view returns (address);
function wantToken() external view returns (address);
function deposit(uint256 amountIn, address receiver)
external
returns (uint256 shares);
function withdraw(uint256 sharesIn, address receiver)
external
returns (uint256 amountOut);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
* https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
*
* Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
* presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
* need to send a transaction, and thus is not required to hold Ether at all.
*/
interface IERC20Permit {
/**
* @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
* given ``owner``'s signed approval.
*
* IMPORTANT: The same issues {IERC20-approve} has related to transaction
* ordering also apply here.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `deadline` must be a timestamp in the future.
* - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
* over the EIP712-formatted function arguments.
* - the signature must use ``owner``'s current nonce (see {nonces}).
*
* For more information on the signature format, see the
* https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
* section].
*/
function permit(
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) external;
/**
* @dev Returns the current nonce for `owner`. This value must be
* included whenever a signature is generated for {permit}.
*
* Every successful call to {permit} increases ``owner``'s nonce by one. This
* prevents a signature from being used multiple times.
*/
function nonces(address owner) external view returns (uint256);
/**
* @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
*/
// solhint-disable-next-line func-name-mixedcase
function DOMAIN_SEPARATOR() external view returns (bytes32);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/ERC20.sol)
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:
*
* - `to` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/
function transfer(address to, uint256 amount) public virtual override returns (bool) {
address owner = _msgSender();
_transfer(owner, to, 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}.
*
* NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
* `transferFrom`. This is semantically equivalent to an infinite approval.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 amount) public virtual override returns (bool) {
address owner = _msgSender();
_approve(owner, 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}.
*
* NOTE: Does not update the allowance if the current allowance
* is the maximum `uint256`.
*
* Requirements:
*
* - `from` and `to` cannot be the zero address.
* - `from` must have a balance of at least `amount`.
* - the caller must have allowance for ``from``'s tokens of at least
* `amount`.
*/
function transferFrom(
address from,
address to,
uint256 amount
) public virtual override returns (bool) {
address spender = _msgSender();
_spendAllowance(from, spender, amount);
_transfer(from, to, 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) {
address owner = _msgSender();
_approve(owner, spender, allowance(owner, 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) {
address owner = _msgSender();
uint256 currentAllowance = allowance(owner, spender);
require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
unchecked {
_approve(owner, 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:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `from` must have a balance of at least `amount`.
*/
function _transfer(
address from,
address to,
uint256 amount
) internal virtual {
require(from != address(0), "ERC20: transfer from the zero address");
require(to != address(0), "ERC20: transfer to the zero address");
_beforeTokenTransfer(from, to, amount);
uint256 fromBalance = _balances[from];
require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
unchecked {
_balances[from] = fromBalance - amount;
}
_balances[to] += amount;
emit Transfer(from, to, amount);
_afterTokenTransfer(from, to, 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 Updates `owner` s allowance for `spender` based on spent `amount`.
*
* Does not update the allowance amount in case of infinite allowance.
* Revert if not enough allowance is available.
*
* Might emit an {Approval} event.
*/
function _spendAllowance(
address owner,
address spender,
uint256 amount
) internal virtual {
uint256 currentAllowance = allowance(owner, spender);
if (currentAllowance != type(uint256).max) {
require(currentAllowance >= amount, "ERC20: insufficient allowance");
unchecked {
_approve(owner, spender, currentAllowance - 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
// OpenZeppelin Contracts v4.4.1 (utils/cryptography/draft-EIP712.sol)
pragma solidity ^0.8.0;
import "./ECDSA.sol";
/**
* @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
*
* The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
* thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
* they need in their contracts using a combination of `abi.encode` and `keccak256`.
*
* This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
* scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
* ({_hashTypedDataV4}).
*
* The implementation of the domain separator was designed to be as efficient as possible while still properly updating
* the chain id to protect against replay attacks on an eventual fork of the chain.
*
* NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
* https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
*
* _Available since v3.4._
*/
abstract contract EIP712 {
/* solhint-disable var-name-mixedcase */
// Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to
// invalidate the cached domain separator if the chain id changes.
bytes32 private immutable _CACHED_DOMAIN_SEPARATOR;
uint256 private immutable _CACHED_CHAIN_ID;
address private immutable _CACHED_THIS;
bytes32 private immutable _HASHED_NAME;
bytes32 private immutable _HASHED_VERSION;
bytes32 private immutable _TYPE_HASH;
/* solhint-enable var-name-mixedcase */
/**
* @dev Initializes the domain separator and parameter caches.
*
* The meaning of `name` and `version` is specified in
* https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
*
* - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
* - `version`: the current major version of the signing domain.
*
* NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
* contract upgrade].
*/
constructor(string memory name, string memory version) {
bytes32 hashedName = keccak256(bytes(name));
bytes32 hashedVersion = keccak256(bytes(version));
bytes32 typeHash = keccak256(
"EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
);
_HASHED_NAME = hashedName;
_HASHED_VERSION = hashedVersion;
_CACHED_CHAIN_ID = block.chainid;
_CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator(typeHash, hashedName, hashedVersion);
_CACHED_THIS = address(this);
_TYPE_HASH = typeHash;
}
/**
* @dev Returns the domain separator for the current chain.
*/
function _domainSeparatorV4() internal view returns (bytes32) {
if (address(this) == _CACHED_THIS && block.chainid == _CACHED_CHAIN_ID) {
return _CACHED_DOMAIN_SEPARATOR;
} else {
return _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION);
}
}
function _buildDomainSeparator(
bytes32 typeHash,
bytes32 nameHash,
bytes32 versionHash
) private view returns (bytes32) {
return keccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this)));
}
/**
* @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
* function returns the hash of the fully encoded EIP712 message for this domain.
*
* This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
*
* ```solidity
* bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
* keccak256("Mail(address to,string contents)"),
* mailTo,
* keccak256(bytes(mailContents))
* )));
* address signer = ECDSA.recover(digest, signature);
* ```
*/
function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
return ECDSA.toTypedDataHash(_domainSeparatorV4(), structHash);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/cryptography/ECDSA.sol)
pragma solidity ^0.8.0;
import "../Strings.sol";
/**
* @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
*
* These functions can be used to verify that a message was signed by the holder
* of the private keys of a given address.
*/
library ECDSA {
enum RecoverError {
NoError,
InvalidSignature,
InvalidSignatureLength,
InvalidSignatureS,
InvalidSignatureV
}
function _throwError(RecoverError error) private pure {
if (error == RecoverError.NoError) {
return; // no error: do nothing
} else if (error == RecoverError.InvalidSignature) {
revert("ECDSA: invalid signature");
} else if (error == RecoverError.InvalidSignatureLength) {
revert("ECDSA: invalid signature length");
} else if (error == RecoverError.InvalidSignatureS) {
revert("ECDSA: invalid signature 's' value");
} else if (error == RecoverError.InvalidSignatureV) {
revert("ECDSA: invalid signature 'v' value");
}
}
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature` or error string. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*
* Documentation for signature generation:
* - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
* - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
*
* _Available since v4.3._
*/
function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
// Check the signature length
// - case 65: r,s,v signature (standard)
// - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._
if (signature.length == 65) {
bytes32 r;
bytes32 s;
uint8 v;
// ecrecover takes the signature parameters, and the only way to get them
// currently is to use assembly.
assembly {
r := mload(add(signature, 0x20))
s := mload(add(signature, 0x40))
v := byte(0, mload(add(signature, 0x60)))
}
return tryRecover(hash, v, r, s);
} else if (signature.length == 64) {
bytes32 r;
bytes32 vs;
// ecrecover takes the signature parameters, and the only way to get them
// currently is to use assembly.
assembly {
r := mload(add(signature, 0x20))
vs := mload(add(signature, 0x40))
}
return tryRecover(hash, r, vs);
} else {
return (address(0), RecoverError.InvalidSignatureLength);
}
}
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature`. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*/
function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, signature);
_throwError(error);
return recovered;
}
/**
* @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
*
* See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
*
* _Available since v4.3._
*/
function tryRecover(
bytes32 hash,
bytes32 r,
bytes32 vs
) internal pure returns (address, RecoverError) {
bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
uint8 v = uint8((uint256(vs) >> 255) + 27);
return tryRecover(hash, v, r, s);
}
/**
* @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
*
* _Available since v4.2._
*/
function recover(
bytes32 hash,
bytes32 r,
bytes32 vs
) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, r, vs);
_throwError(error);
return recovered;
}
/**
* @dev Overload of {ECDSA-tryRecover} that receives the `v`,
* `r` and `s` signature fields separately.
*
* _Available since v4.3._
*/
function tryRecover(
bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internal pure returns (address, RecoverError) {
// EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
// unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
// the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
// signatures from current libraries generate a unique signature with an s-value in the lower half order.
//
// If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
// with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
// vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
// these malleable signatures as well.
if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
return (address(0), RecoverError.InvalidSignatureS);
}
if (v != 27 && v != 28) {
return (address(0), RecoverError.InvalidSignatureV);
}
// If the signature is valid (and not malleable), return the signer address
address signer = ecrecover(hash, v, r, s);
if (signer == address(0)) {
return (address(0), RecoverError.InvalidSignature);
}
return (signer, RecoverError.NoError);
}
/**
* @dev Overload of {ECDSA-recover} that receives the `v`,
* `r` and `s` signature fields separately.
*/
function recover(
bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, v, r, s);
_throwError(error);
return recovered;
}
/**
* @dev Returns an Ethereum Signed Message, created from a `hash`. This
* produces hash corresponding to the one signed with the
* https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
* JSON-RPC method as part of EIP-191.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
// 32 is the length in bytes of hash,
// enforced by the type signature above
return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
}
/**
* @dev Returns an Ethereum Signed Message, created from `s`. This
* produces hash corresponding to the one signed with the
* https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
* JSON-RPC method as part of EIP-191.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(s.length), s));
}
/**
* @dev Returns an Ethereum Signed Typed Data, created from a
* `domainSeparator` and a `structHash`. This produces hash corresponding
* to the one signed with the
* https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
* JSON-RPC method as part of EIP-712.
*
* See {recover}.
*/
function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
return keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Counters.sol)
pragma solidity ^0.8.0;
/**
* @title Counters
* @author Matt Condon (@shrugs)
* @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
* of elements in a mapping, issuing ERC721 ids, or counting request ids.
*
* Include with `using Counters for Counters.Counter;`
*/
library Counters {
struct Counter {
// This variable should never be directly accessed by users of the library: interactions must be restricted to
// the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
// this feature: see https://github.com/ethereum/solidity/issues/4637
uint256 _value; // default: 0
}
function current(Counter storage counter) internal view returns (uint256) {
return counter._value;
}
function increment(Counter storage counter) internal {
unchecked {
counter._value += 1;
}
}
function decrement(Counter storage counter) internal {
uint256 value = counter._value;
require(value > 0, "Counter: decrement overflow");
unchecked {
counter._value = value - 1;
}
}
function reset(Counter storage counter) internal {
counter._value = 0;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
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
// 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/Strings.sol)
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
// OpenZeppelin Contracts (last updated v4.5.0) (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
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
