Contract Name:
SturdySiloStrategy
Contract Source Code:
File 1 of 1 : SturdySiloStrategy
// SPDX-License-Identifier: AGPL-3.0
pragma solidity 0.8.21;
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)
/**
* @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);
}
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.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);
}
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
/**
* @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;
}
}
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}.
*
* 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 default value returned by this function, unless
* it's 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 `from` to `to`.
*
* 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;
// Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
// decrementing then incrementing.
_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;
unchecked {
// Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
_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;
// Overflow not possible: amount <= accountBalance <= totalSupply.
_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 {}
}
interface IERC4626 is IERC20, IERC20Metadata {
event Deposit(address indexed sender, address indexed owner, uint256 assets, uint256 shares);
event Withdraw(
address indexed sender,
address indexed receiver,
address indexed owner,
uint256 assets,
uint256 shares
);
/**
* @dev Returns the address of the underlying token used for the Vault for accounting, depositing, and withdrawing.
*
* - MUST be an ERC-20 token contract.
* - MUST NOT revert.
*/
function asset() external view returns (address assetTokenAddress);
/**
* @dev Returns the total amount of the underlying asset that is “managed” by Vault.
*
* - SHOULD include any compounding that occurs from yield.
* - MUST be inclusive of any fees that are charged against assets in the Vault.
* - MUST NOT revert.
*/
function totalAssets() external view returns (uint256 totalManagedAssets);
/**
* @dev Returns the amount of shares that the Vault would exchange for the amount of assets provided, in an ideal
* scenario where all the conditions are met.
*
* - MUST NOT be inclusive of any fees that are charged against assets in the Vault.
* - MUST NOT show any variations depending on the caller.
* - MUST NOT reflect slippage or other on-chain conditions, when performing the actual exchange.
* - MUST NOT revert.
*
* NOTE: This calculation MAY NOT reflect the “per-user” price-per-share, and instead should reflect the
* “average-user’s” price-per-share, meaning what the average user should expect to see when exchanging to and
* from.
*/
function convertToShares(uint256 assets) external view returns (uint256 shares);
/**
* @dev Returns the amount of assets that the Vault would exchange for the amount of shares provided, in an ideal
* scenario where all the conditions are met.
*
* - MUST NOT be inclusive of any fees that are charged against assets in the Vault.
* - MUST NOT show any variations depending on the caller.
* - MUST NOT reflect slippage or other on-chain conditions, when performing the actual exchange.
* - MUST NOT revert.
*
* NOTE: This calculation MAY NOT reflect the “per-user” price-per-share, and instead should reflect the
* “average-user’s” price-per-share, meaning what the average user should expect to see when exchanging to and
* from.
*/
function convertToAssets(uint256 shares) external view returns (uint256 assets);
/**
* @dev Returns the maximum amount of the underlying asset that can be deposited into the Vault for the receiver,
* through a deposit call.
*
* - MUST return a limited value if receiver is subject to some deposit limit.
* - MUST return 2 ** 256 - 1 if there is no limit on the maximum amount of assets that may be deposited.
* - MUST NOT revert.
*/
function maxDeposit(address receiver) external view returns (uint256 maxAssets);
/**
* @dev Allows an on-chain or off-chain user to simulate the effects of their deposit at the current block, given
* current on-chain conditions.
*
* - MUST return as close to and no more than the exact amount of Vault shares that would be minted in a deposit
* call in the same transaction. I.e. deposit should return the same or more shares as previewDeposit if called
* in the same transaction.
* - MUST NOT account for deposit limits like those returned from maxDeposit and should always act as though the
* deposit would be accepted, regardless if the user has enough tokens approved, etc.
* - MUST be inclusive of deposit fees. Integrators should be aware of the existence of deposit fees.
* - MUST NOT revert.
*
* NOTE: any unfavorable discrepancy between convertToShares and previewDeposit SHOULD be considered slippage in
* share price or some other type of condition, meaning the depositor will lose assets by depositing.
*/
function previewDeposit(uint256 assets) external view returns (uint256 shares);
/**
* @dev Mints shares Vault shares to receiver by depositing exactly amount of underlying tokens.
*
* - MUST emit the Deposit event.
* - MAY support an additional flow in which the underlying tokens are owned by the Vault contract before the
* deposit execution, and are accounted for during deposit.
* - MUST revert if all of assets cannot be deposited (due to deposit limit being reached, slippage, the user not
* approving enough underlying tokens to the Vault contract, etc).
*
* NOTE: most implementations will require pre-approval of the Vault with the Vault’s underlying asset token.
*/
function deposit(uint256 assets, address receiver) external returns (uint256 shares);
/**
* @dev Returns the maximum amount of the Vault shares that can be minted for the receiver, through a mint call.
* - MUST return a limited value if receiver is subject to some mint limit.
* - MUST return 2 ** 256 - 1 if there is no limit on the maximum amount of shares that may be minted.
* - MUST NOT revert.
*/
function maxMint(address receiver) external view returns (uint256 maxShares);
/**
* @dev Allows an on-chain or off-chain user to simulate the effects of their mint at the current block, given
* current on-chain conditions.
*
* - MUST return as close to and no fewer than the exact amount of assets that would be deposited in a mint call
* in the same transaction. I.e. mint should return the same or fewer assets as previewMint if called in the
* same transaction.
* - MUST NOT account for mint limits like those returned from maxMint and should always act as though the mint
* would be accepted, regardless if the user has enough tokens approved, etc.
* - MUST be inclusive of deposit fees. Integrators should be aware of the existence of deposit fees.
* - MUST NOT revert.
*
* NOTE: any unfavorable discrepancy between convertToAssets and previewMint SHOULD be considered slippage in
* share price or some other type of condition, meaning the depositor will lose assets by minting.
*/
function previewMint(uint256 shares) external view returns (uint256 assets);
/**
* @dev Mints exactly shares Vault shares to receiver by depositing amount of underlying tokens.
*
* - MUST emit the Deposit event.
* - MAY support an additional flow in which the underlying tokens are owned by the Vault contract before the mint
* execution, and are accounted for during mint.
* - MUST revert if all of shares cannot be minted (due to deposit limit being reached, slippage, the user not
* approving enough underlying tokens to the Vault contract, etc).
*
* NOTE: most implementations will require pre-approval of the Vault with the Vault’s underlying asset token.
*/
function mint(uint256 shares, address receiver) external returns (uint256 assets);
/**
* @dev Returns the maximum amount of the underlying asset that can be withdrawn from the owner balance in the
* Vault, through a withdraw call.
*
* - MUST return a limited value if owner is subject to some withdrawal limit or timelock.
* - MUST NOT revert.
*/
function maxWithdraw(address owner) external view returns (uint256 maxAssets);
/**
* @dev Allows an on-chain or off-chain user to simulate the effects of their withdrawal at the current block,
* given current on-chain conditions.
*
* - MUST return as close to and no fewer than the exact amount of Vault shares that would be burned in a withdraw
* call in the same transaction. I.e. withdraw should return the same or fewer shares as previewWithdraw if
* called
* in the same transaction.
* - MUST NOT account for withdrawal limits like those returned from maxWithdraw and should always act as though
* the withdrawal would be accepted, regardless if the user has enough shares, etc.
* - MUST be inclusive of withdrawal fees. Integrators should be aware of the existence of withdrawal fees.
* - MUST NOT revert.
*
* NOTE: any unfavorable discrepancy between convertToShares and previewWithdraw SHOULD be considered slippage in
* share price or some other type of condition, meaning the depositor will lose assets by depositing.
*/
function previewWithdraw(uint256 assets) external view returns (uint256 shares);
/**
* @dev Burns shares from owner and sends exactly assets of underlying tokens to receiver.
*
* - MUST emit the Withdraw event.
* - MAY support an additional flow in which the underlying tokens are owned by the Vault contract before the
* withdraw execution, and are accounted for during withdraw.
* - MUST revert if all of assets cannot be withdrawn (due to withdrawal limit being reached, slippage, the owner
* not having enough shares, etc).
*
* Note that some implementations will require pre-requesting to the Vault before a withdrawal may be performed.
* Those methods should be performed separately.
*/
function withdraw(uint256 assets, address receiver, address owner) external returns (uint256 shares);
/**
* @dev Returns the maximum amount of Vault shares that can be redeemed from the owner balance in the Vault,
* through a redeem call.
*
* - MUST return a limited value if owner is subject to some withdrawal limit or timelock.
* - MUST return balanceOf(owner) if owner is not subject to any withdrawal limit or timelock.
* - MUST NOT revert.
*/
function maxRedeem(address owner) external view returns (uint256 maxShares);
/**
* @dev Allows an on-chain or off-chain user to simulate the effects of their redeemption at the current block,
* given current on-chain conditions.
*
* - MUST return as close to and no more than the exact amount of assets that would be withdrawn in a redeem call
* in the same transaction. I.e. redeem should return the same or more assets as previewRedeem if called in the
* same transaction.
* - MUST NOT account for redemption limits like those returned from maxRedeem and should always act as though the
* redemption would be accepted, regardless if the user has enough shares, etc.
* - MUST be inclusive of withdrawal fees. Integrators should be aware of the existence of withdrawal fees.
* - MUST NOT revert.
*
* NOTE: any unfavorable discrepancy between convertToAssets and previewRedeem SHOULD be considered slippage in
* share price or some other type of condition, meaning the depositor will lose assets by redeeming.
*/
function previewRedeem(uint256 shares) external view returns (uint256 assets);
/**
* @dev Burns exactly shares from owner and sends assets of underlying tokens to receiver.
*
* - MUST emit the Withdraw event.
* - MAY support an additional flow in which the underlying tokens are owned by the Vault contract before the
* redeem execution, and are accounted for during redeem.
* - MUST revert if all of shares cannot be redeemed (due to withdrawal limit being reached, slippage, the owner
* not having enough shares, etc).
*
* NOTE: some implementations will require pre-requesting to the Vault before a withdrawal may be performed.
* Those methods should be performed separately.
*/
function redeem(uint256 shares, address receiver, address owner) external returns (uint256 assets);
}
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/extensions/IERC20Permit.sol)
/**
* @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);
}
interface ITokenizedStrategy is IERC4626, IERC20Permit {
/*//////////////////////////////////////////////////////////////
EVENTS
//////////////////////////////////////////////////////////////*/
event UpdatePendingManagement(address indexed newPendingManagement);
event UpdateManagement(address indexed newManagement);
event UpdateKeeper(address indexed newKeeper);
event UpdateEmergencyAdmin(address indexed newEmergencyAdmin);
event UpdatePerformanceFee(uint16 newPerformanceFee);
event UpdatePerformanceFeeRecipient(
address indexed newPerformanceFeeRecipient
);
event UpdateProfitMaxUnlockTime(uint256 newProfitMaxUnlockTime);
event StrategyShutdown();
event Reported(
uint256 profit,
uint256 loss,
uint256 protocolFees,
uint256 performanceFees
);
/*//////////////////////////////////////////////////////////////
INITIALIZATION
//////////////////////////////////////////////////////////////*/
function init(
address _asset,
string memory _name,
address _management,
address _performanceFeeRecipient,
address _keeper
) external;
/*//////////////////////////////////////////////////////////////
NON-STANDARD 4626 OPTIONS
//////////////////////////////////////////////////////////////*/
function withdraw(
uint256 assets,
address receiver,
address owner,
uint256 maxLoss
) external returns (uint256);
function redeem(
uint256 shares,
address receiver,
address owner,
uint256 maxLoss
) external returns (uint256);
/*//////////////////////////////////////////////////////////////
MODIFIERS
//////////////////////////////////////////////////////////////*/
function isManagement(address _sender) external view returns (bool);
function isKeeperOrManagement(address _sender) external view returns (bool);
function isEmergencyAuthorized(
address _sender
) external view returns (bool);
/*//////////////////////////////////////////////////////////////
KEEPERS FUNCTIONS
//////////////////////////////////////////////////////////////*/
function tend() external;
function report() external returns (uint256 _profit, uint256 _loss);
/*//////////////////////////////////////////////////////////////
CONSTANTS
//////////////////////////////////////////////////////////////*/
function MIN_FEE() external view returns (uint16);
function MAX_FEE() external view returns (uint16);
function FACTORY() external view returns (address);
/*//////////////////////////////////////////////////////////////
GETTERS
//////////////////////////////////////////////////////////////*/
function apiVersion() external view returns (string memory);
function pricePerShare() external view returns (uint256);
function totalIdle() external view returns (uint256);
function totalDebt() external view returns (uint256);
function management() external view returns (address);
function pendingManagement() external view returns (address);
function keeper() external view returns (address);
function emergencyAdmin() external view returns (address);
function performanceFee() external view returns (uint16);
function performanceFeeRecipient() external view returns (address);
function fullProfitUnlockDate() external view returns (uint256);
function profitUnlockingRate() external view returns (uint256);
function profitMaxUnlockTime() external view returns (uint256);
function lastReport() external view returns (uint256);
function isShutdown() external view returns (bool);
function unlockedShares() external view returns (uint256);
/*//////////////////////////////////////////////////////////////
SETTERS
//////////////////////////////////////////////////////////////*/
function setPendingManagement(address) external;
function acceptManagement() external;
function setKeeper(address _keeper) external;
function setEmergencyAdmin(address _emergencyAdmin) external;
function setPerformanceFee(uint16 _performanceFee) external;
function setPerformanceFeeRecipient(
address _performanceFeeRecipient
) external;
function setProfitMaxUnlockTime(uint256 _profitMaxUnlockTime) external;
function shutdownStrategy() external;
function emergencyWithdraw(uint256 _amount) external;
/*//////////////////////////////////////////////////////////////
ERC20 ADD ONS
//////////////////////////////////////////////////////////////*/
function decreaseAllowance(
address spender,
uint256 subtractedValue
) external returns (bool);
function increaseAllowance(
address spender,
uint256 addedValue
) external returns (bool);
}
abstract contract BaseStrategy {
/*//////////////////////////////////////////////////////////////
MODIFIERS
//////////////////////////////////////////////////////////////*/
/**
* @dev Used on TokenizedStrategy callback functions to make sure it is post
* a delegateCall from this address to the TokenizedStrategy.
*/
modifier onlySelf() {
_onlySelf();
_;
}
/**
* @dev Use to assure that the call is coming from the strategies management.
*/
modifier onlyManagement() {
TokenizedStrategy.isManagement(msg.sender);
_;
}
/**
* @dev Use to assure that the call is coming from either the strategies
* management or the keeper.
*/
modifier onlyKeepers() {
TokenizedStrategy.isKeeperOrManagement(msg.sender);
_;
}
/**
* @dev Use to assure that the call is coming from either the strategies
* management or the emergency admin.
*/
modifier onlyEmergencyAuthorized() {
TokenizedStrategy.isEmergencyAuthorized(msg.sender);
_;
}
function _onlySelf() internal view {
require(msg.sender == address(this), "!self");
}
/*//////////////////////////////////////////////////////////////
CONSTANTS
//////////////////////////////////////////////////////////////*/
/**
* This is the address of the TokenizedStrategy implementation
* contract that will be used by all strategies to handle the
* accounting, logic, storage etc.
*
* Any external calls to the that don't hit one of the functions
* defined in this base or the strategy will end up being forwarded
* through the fallback function, which will delegateCall this address.
*
* This address should be the same for every strategy, never be adjusted
* and always be checked before any integration with the Strategy.
*/
address public constant tokenizedStrategyAddress =
0xDFC8cD9F2f2d306b7C0d109F005DF661E14f4ff2;
/*//////////////////////////////////////////////////////////////
IMMUTABLES
//////////////////////////////////////////////////////////////*/
/**
* This variable is set to address(this) during initialization of each strategy.
*
* This can be used to retrieve storage data within the strategy
* contract as if it were a linked library.
*
* i.e. uint256 totalAssets = TokenizedStrategy.totalAssets()
*
* Using address(this) will mean any calls using this variable will lead
* to a call to itself. Which will hit the fallback function and
* delegateCall that to the actual TokenizedStrategy.
*/
ITokenizedStrategy internal immutable TokenizedStrategy;
// Underlying asset the Strategy is earning yield on.
// Stored here for cheap retrievals within the strategy.
ERC20 internal immutable asset;
/**
* @notice Used to initialize the strategy on deployment.
*
* This will set the `TokenizedStrategy` variable for easy
* internal view calls to the implementation. As well as
* initializing the default storage variables based on the
* parameters and using the deployer for the permissioned roles.
*
* @param _asset Address of the underlying asset.
* @param _name Name the strategy will use.
*/
constructor(address _asset, string memory _name) {
asset = ERC20(_asset);
// Set instance of the implementation for internal use.
TokenizedStrategy = ITokenizedStrategy(address(this));
// Initialize the strategy's storage variables.
_delegateCall(
abi.encodeCall(
ITokenizedStrategy.init,
(_asset, _name, msg.sender, msg.sender, msg.sender)
)
);
// Store the tokenizedStrategyAddress at the standard implementation
// address storage slot so etherscan picks up the interface. This gets
// stored on initialization and never updated.
assembly {
sstore(
// keccak256('eip1967.proxy.implementation' - 1)
0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc,
tokenizedStrategyAddress
)
}
}
/*//////////////////////////////////////////////////////////////
NEEDED TO BE OVERRIDDEN BY STRATEGIST
//////////////////////////////////////////////////////////////*/
/**
* @dev Should deploy up to '_amount' of 'asset' in the yield source.
*
* This function is called at the end of a {deposit} or {mint}
* call. Meaning that unless a whitelist is implemented it will
* be entirely permissionless and thus can be sandwiched or otherwise
* manipulated.
*
* @param _amount The amount of 'asset' that the strategy should attempt
* to deposit in the yield source.
*/
function _deployFunds(uint256 _amount) internal virtual;
/**
* @dev Will attempt to free the '_amount' of 'asset'.
*
* The amount of 'asset' that is already loose has already
* been accounted for.
*
* This function is called during {withdraw} and {redeem} calls.
* Meaning that unless a whitelist is implemented it will be
* entirely permissionless and thus can be sandwiched or otherwise
* manipulated.
*
* Should not rely on asset.balanceOf(address(this)) calls other than
* for diff accounting purposes.
*
* Any difference between `_amount` and what is actually freed will be
* counted as a loss and passed on to the withdrawer. This means
* care should be taken in times of illiquidity. It may be better to revert
* if withdraws are simply illiquid so not to realize incorrect losses.
*
* @param _amount, The amount of 'asset' to be freed.
*/
function _freeFunds(uint256 _amount) internal virtual;
/**
* @dev Internal function to harvest all rewards, redeploy any idle
* funds and return an accurate accounting of all funds currently
* held by the Strategy.
*
* This should do any needed harvesting, rewards selling, accrual,
* redepositing etc. to get the most accurate view of current assets.
*
* NOTE: All applicable assets including loose assets should be
* accounted for in this function.
*
* Care should be taken when relying on oracles or swap values rather
* than actual amounts as all Strategy profit/loss accounting will
* be done based on this returned value.
*
* This can still be called post a shutdown, a strategist can check
* `TokenizedStrategy.isShutdown()` to decide if funds should be
* redeployed or simply realize any profits/losses.
*
* @return _totalAssets A trusted and accurate account for the total
* amount of 'asset' the strategy currently holds including idle funds.
*/
function _harvestAndReport()
internal
virtual
returns (uint256 _totalAssets);
/*//////////////////////////////////////////////////////////////
OPTIONAL TO OVERRIDE BY STRATEGIST
//////////////////////////////////////////////////////////////*/
/**
* @dev Optional function for strategist to override that can
* be called in between reports.
*
* If '_tend' is used tendTrigger() will also need to be overridden.
*
* This call can only be called by a permissioned role so may be
* through protected relays.
*
* This can be used to harvest and compound rewards, deposit idle funds,
* perform needed position maintenance or anything else that doesn't need
* a full report for.
*
* EX: A strategy that can not deposit funds without getting
* sandwiched can use the tend when a certain threshold
* of idle to totalAssets has been reached.
*
* The TokenizedStrategy contract will do all needed debt and idle updates
* after this has finished and will have no effect on PPS of the strategy
* till report() is called.
*
* @param _totalIdle The current amount of idle funds that are available to deploy.
*/
function _tend(uint256 _totalIdle) internal virtual {}
/**
* @dev Optional trigger to override if tend() will be used by the strategy.
* This must be implemented if the strategy hopes to invoke _tend().
*
* @return . Should return true if tend() should be called by keeper or false if not.
*/
function _tendTrigger() internal view virtual returns (bool) {
return false;
}
/**
* @notice Returns if tend() should be called by a keeper.
*
* @return . Should return true if tend() should be called by keeper or false if not.
* @return . Calldata for the tend call.
*/
function tendTrigger() external view virtual returns (bool, bytes memory) {
return (
// Return the status of the tend trigger.
_tendTrigger(),
// And the needed calldata either way.
abi.encodeWithSelector(ITokenizedStrategy.tend.selector)
);
}
/**
* @notice Gets the max amount of `asset` that an address can deposit.
* @dev Defaults to an unlimited amount for any address. But can
* be overridden by strategists.
*
* This function will be called before any deposit or mints to enforce
* any limits desired by the strategist. This can be used for either a
* traditional deposit limit or for implementing a whitelist etc.
*
* EX:
* if(isAllowed[_owner]) return super.availableDepositLimit(_owner);
*
* This does not need to take into account any conversion rates
* from shares to assets. But should know that any non max uint256
* amounts may be converted to shares. So it is recommended to keep
* custom amounts low enough as not to cause overflow when multiplied
* by `totalSupply`.
*
* @param . The address that is depositing into the strategy.
* @return . The available amount the `_owner` can deposit in terms of `asset`
*/
function availableDepositLimit(
address /*_owner*/
) public view virtual returns (uint256) {
return type(uint256).max;
}
/**
* @notice Gets the max amount of `asset` that can be withdrawn.
* @dev Defaults to an unlimited amount for any address. But can
* be overridden by strategists.
*
* This function will be called before any withdraw or redeem to enforce
* any limits desired by the strategist. This can be used for illiquid
* or sandwichable strategies. It should never be lower than `totalIdle`.
*
* EX:
* return TokenIzedStrategy.totalIdle();
*
* This does not need to take into account the `_owner`'s share balance
* or conversion rates from shares to assets.
*
* @param . The address that is withdrawing from the strategy.
* @return . The available amount that can be withdrawn in terms of `asset`
*/
function availableWithdrawLimit(
address /*_owner*/
) public view virtual returns (uint256) {
return type(uint256).max;
}
/**
* @dev Optional function for a strategist to override that will
* allow management to manually withdraw deployed funds from the
* yield source if a strategy is shutdown.
*
* This should attempt to free `_amount`, noting that `_amount` may
* be more than is currently deployed.
*
* NOTE: This will not realize any profits or losses. A separate
* {report} will be needed in order to record any profit/loss. If
* a report may need to be called after a shutdown it is important
* to check if the strategy is shutdown during {_harvestAndReport}
* so that it does not simply re-deploy all funds that had been freed.
*
* EX:
* if(freeAsset > 0 && !TokenizedStrategy.isShutdown()) {
* depositFunds...
* }
*
* @param _amount The amount of asset to attempt to free.
*/
function _emergencyWithdraw(uint256 _amount) internal virtual {}
/*//////////////////////////////////////////////////////////////
TokenizedStrategy HOOKS
//////////////////////////////////////////////////////////////*/
/**
* @notice Should deploy up to '_amount' of 'asset' in yield source.
* @dev Callback for the TokenizedStrategy to call during a {deposit}
* or {mint} to tell the strategy it can deploy funds.
*
* Since this can only be called after a {deposit} or {mint}
* delegateCall to the TokenizedStrategy msg.sender == address(this).
*
* Unless a whitelist is implemented this will be entirely permissionless
* and thus can be sandwiched or otherwise manipulated.
*
* @param _amount The amount of 'asset' that the strategy should
* attempt to deposit in the yield source.
*/
function deployFunds(uint256 _amount) external virtual onlySelf {
_deployFunds(_amount);
}
/**
* @notice Will attempt to free the '_amount' of 'asset'.
* @dev Callback for the TokenizedStrategy to call during a withdraw
* or redeem to free the needed funds to service the withdraw.
*
* This can only be called after a 'withdraw' or 'redeem' delegateCall
* to the TokenizedStrategy so msg.sender == address(this).
*
* @param _amount The amount of 'asset' that the strategy should attempt to free up.
*/
function freeFunds(uint256 _amount) external virtual onlySelf {
_freeFunds(_amount);
}
/**
* @notice Returns the accurate amount of all funds currently
* held by the Strategy.
* @dev Callback for the TokenizedStrategy to call during a report to
* get an accurate accounting of assets the strategy controls.
*
* This can only be called after a report() delegateCall to the
* TokenizedStrategy so msg.sender == address(this).
*
* @return . A trusted and accurate account for the total amount
* of 'asset' the strategy currently holds including idle funds.
*/
function harvestAndReport() external virtual onlySelf returns (uint256) {
return _harvestAndReport();
}
/**
* @notice Will call the internal '_tend' when a keeper tends the strategy.
* @dev Callback for the TokenizedStrategy to initiate a _tend call in the strategy.
*
* This can only be called after a tend() delegateCall to the TokenizedStrategy
* so msg.sender == address(this).
*
* We name the function `tendThis` so that `tend` calls are forwarded to
* the TokenizedStrategy so it can do the necessary accounting.
* @param _totalIdle The amount of current idle funds that can be
* deployed during the tend
*/
function tendThis(uint256 _totalIdle) external virtual onlySelf {
_tend(_totalIdle);
}
/**
* @notice Will call the internal '_emergencyWithdraw' function.
* @dev Callback for the TokenizedStrategy during an emergency withdraw.
*
* This can only be called after a emergencyWithdraw() delegateCall to
* the TokenizedStrategy so msg.sender == address(this).
*
* We name the function `shutdownWithdraw` so that `emergencyWithdraw`
* calls are forwarded to the TokenizedStrategy so it can do the necessary
* accounting after the withdraw.
*
* @param _amount The amount of asset to attempt to free.
*/
function shutdownWithdraw(uint256 _amount) external virtual onlySelf {
_emergencyWithdraw(_amount);
}
function maxLTV() external view virtual returns (uint256);
function collateral() external view virtual returns (address);
/**
* @dev Function used to delegate call the TokenizedStrategy with
* certain `_calldata` and return any return values.
*
* This is used to setup the initial storage of the strategy, and
* can be used by strategist to forward any other call to the
* TokenizedStrategy implementation.
*
* @param _calldata The abi encoded calldata to use in delegatecall.
* @return . The return value if the call was successful in bytes.
*/
function _delegateCall(
bytes memory _calldata
) internal returns (bytes memory) {
// Delegate call the tokenized strategy with provided calldata.
(bool success, bytes memory result) = tokenizedStrategyAddress
.delegatecall(_calldata);
// If the call reverted. Return the error.
if (!success) {
assembly {
let ptr := mload(0x40)
let size := returndatasize()
returndatacopy(ptr, 0, size)
revert(ptr, size)
}
}
// Return the result.
return result;
}
// execute a function on the TokenizedStrategy and return any value.
fallback() external {
// load our target address
address _tokenizedStrategyAddress = tokenizedStrategyAddress;
// Execute external function using delegatecall and return any value.
assembly {
// Copy function selector and any arguments.
calldatacopy(0, 0, calldatasize())
// Execute function delegatecall.
let result := delegatecall(
gas(),
_tokenizedStrategyAddress,
0,
calldatasize(),
0,
0
)
// Get any return value
returndatacopy(0, 0, returndatasize())
// Return any return value or error back to the caller
switch result
case 0 {
revert(0, returndatasize())
}
default {
return(0, returndatasize())
}
}
}
}
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)
/**
* @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
*
* Furthermore, `isContract` will also return true if the target contract within
* the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
* which only has an effect at the end of a transaction.
* ====
*
* [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://consensys.net/diligence/blog/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/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
(bool success, bytes memory returndata) = target.call{value: value}(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(
address target,
bytes memory data,
string memory errorMessage
) internal view returns (bytes memory) {
(bool success, bytes memory returndata) = target.staticcall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev 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) {
(bool success, bytes memory returndata) = target.delegatecall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
* the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
*
* _Available since v4.8._
*/
function verifyCallResultFromTarget(
address target,
bool success,
bytes memory returndata,
string memory errorMessage
) internal view returns (bytes memory) {
if (success) {
if (returndata.length == 0) {
// only check isContract if the call was successful and the return data is empty
// otherwise we already know that it was a contract
require(isContract(target), "Address: call to non-contract");
}
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
/**
* @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason or using the provided one.
*
* _Available since v4.3._
*/
function verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) internal pure returns (bytes memory) {
if (success) {
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
function _revert(bytes memory returndata, string memory errorMessage) private pure {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
/// @solidity memory-safe-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
library SafeERC20 {
using Address for address;
/**
* @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeTransfer(IERC20 token, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
/**
* @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
* calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
*/
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));
}
/**
* @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 oldAllowance = token.allowance(address(this), spender);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
}
/**
* @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
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");
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
}
}
/**
* @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
* to be set to zero before setting it to a non-zero value, such as USDT.
*/
function forceApprove(IERC20 token, address spender, uint256 value) internal {
bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);
if (!_callOptionalReturnBool(token, approvalCall)) {
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
_callOptionalReturn(token, approvalCall);
}
}
/**
* @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
* Revert on invalid signature.
*/
function safePermit(
IERC20Permit token,
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) internal {
uint256 nonceBefore = token.nonces(owner);
token.permit(owner, spender, value, deadline, v, r, s);
uint256 nonceAfter = token.nonces(owner);
require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
}
/**
* @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");
require(returndata.length == 0 || abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
/**
* @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).
*
* This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
*/
function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
// 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 cannot use {Address-functionCall} here since this should return false
// and not revert is the subcall reverts.
(bool success, bytes memory returndata) = address(token).call(data);
return
success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
}
}
library Math {
enum Rounding {
Down, // Toward negative infinity
Up, // Toward infinity
Zero // Toward zero
}
/**
* @dev Returns the largest of two numbers.
*/
function max(uint256 a, uint256 b) internal pure returns (uint256) {
return a > b ? a : b;
}
/**
* @dev Returns the smallest of two numbers.
*/
function min(uint256 a, uint256 b) internal pure returns (uint256) {
return a < b ? a : b;
}
/**
* @dev Returns the average of two numbers. The result is rounded towards
* zero.
*/
function average(uint256 a, uint256 b) internal pure returns (uint256) {
// (a + b) / 2 can overflow.
return (a & b) + (a ^ b) / 2;
}
/**
* @dev Returns the ceiling of the division of two numbers.
*
* This differs from standard division with `/` in that it rounds up instead
* of rounding down.
*/
function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
// (a + b - 1) / b can overflow on addition, so we distribute.
return a == 0 ? 0 : (a - 1) / b + 1;
}
/**
* @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
* @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
* with further edits by Uniswap Labs also under MIT license.
*/
function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
unchecked {
// 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
// use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
// variables such that product = prod1 * 2^256 + prod0.
uint256 prod0; // Least significant 256 bits of the product
uint256 prod1; // Most significant 256 bits of the product
assembly {
let mm := mulmod(x, y, not(0))
prod0 := mul(x, y)
prod1 := sub(sub(mm, prod0), lt(mm, prod0))
}
// Handle non-overflow cases, 256 by 256 division.
if (prod1 == 0) {
// Solidity will revert if denominator == 0, unlike the div opcode on its own.
// The surrounding unchecked block does not change this fact.
// See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
return prod0 / denominator;
}
// Make sure the result is less than 2^256. Also prevents denominator == 0.
require(denominator > prod1, "Math: mulDiv overflow");
///////////////////////////////////////////////
// 512 by 256 division.
///////////////////////////////////////////////
// Make division exact by subtracting the remainder from [prod1 prod0].
uint256 remainder;
assembly {
// Compute remainder using mulmod.
remainder := mulmod(x, y, denominator)
// Subtract 256 bit number from 512 bit number.
prod1 := sub(prod1, gt(remainder, prod0))
prod0 := sub(prod0, remainder)
}
// Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
// See https://cs.stackexchange.com/q/138556/92363.
// Does not overflow because the denominator cannot be zero at this stage in the function.
uint256 twos = denominator & (~denominator + 1);
assembly {
// Divide denominator by twos.
denominator := div(denominator, twos)
// Divide [prod1 prod0] by twos.
prod0 := div(prod0, twos)
// Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
twos := add(div(sub(0, twos), twos), 1)
}
// Shift in bits from prod1 into prod0.
prod0 |= prod1 * twos;
// Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
// that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
// four bits. That is, denominator * inv = 1 mod 2^4.
uint256 inverse = (3 * denominator) ^ 2;
// Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
// in modular arithmetic, doubling the correct bits in each step.
inverse *= 2 - denominator * inverse; // inverse mod 2^8
inverse *= 2 - denominator * inverse; // inverse mod 2^16
inverse *= 2 - denominator * inverse; // inverse mod 2^32
inverse *= 2 - denominator * inverse; // inverse mod 2^64
inverse *= 2 - denominator * inverse; // inverse mod 2^128
inverse *= 2 - denominator * inverse; // inverse mod 2^256
// Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
// This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
// less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
// is no longer required.
result = prod0 * inverse;
return result;
}
}
/**
* @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
*/
function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (uint256) {
uint256 result = mulDiv(x, y, denominator);
if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
result += 1;
}
return result;
}
/**
* @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
*
* Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
*/
function sqrt(uint256 a) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
// For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
//
// We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
// `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
//
// This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
// → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
// → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
//
// Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
uint256 result = 1 << (log2(a) >> 1);
// At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
// since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
// every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
// into the expected uint128 result.
unchecked {
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
return min(result, a / result);
}
}
/**
* @notice Calculates sqrt(a), following the selected rounding direction.
*/
function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
unchecked {
uint256 result = sqrt(a);
return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
}
}
/**
* @dev Return the log in base 2, rounded down, of a positive value.
* Returns 0 if given 0.
*/
function log2(uint256 value) internal pure returns (uint256) {
uint256 result = 0;
unchecked {
if (value >> 128 > 0) {
value >>= 128;
result += 128;
}
if (value >> 64 > 0) {
value >>= 64;
result += 64;
}
if (value >> 32 > 0) {
value >>= 32;
result += 32;
}
if (value >> 16 > 0) {
value >>= 16;
result += 16;
}
if (value >> 8 > 0) {
value >>= 8;
result += 8;
}
if (value >> 4 > 0) {
value >>= 4;
result += 4;
}
if (value >> 2 > 0) {
value >>= 2;
result += 2;
}
if (value >> 1 > 0) {
result += 1;
}
}
return result;
}
/**
* @dev Return the log in base 2, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/
function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
unchecked {
uint256 result = log2(value);
return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
}
}
/**
* @dev Return the log in base 10, rounded down, of a positive value.
* Returns 0 if given 0.
*/
function log10(uint256 value) internal pure returns (uint256) {
uint256 result = 0;
unchecked {
if (value >= 10 ** 64) {
value /= 10 ** 64;
result += 64;
}
if (value >= 10 ** 32) {
value /= 10 ** 32;
result += 32;
}
if (value >= 10 ** 16) {
value /= 10 ** 16;
result += 16;
}
if (value >= 10 ** 8) {
value /= 10 ** 8;
result += 8;
}
if (value >= 10 ** 4) {
value /= 10 ** 4;
result += 4;
}
if (value >= 10 ** 2) {
value /= 10 ** 2;
result += 2;
}
if (value >= 10 ** 1) {
result += 1;
}
}
return result;
}
/**
* @dev Return the log in base 10, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/
function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
unchecked {
uint256 result = log10(value);
return result + (rounding == Rounding.Up && 10 ** result < value ? 1 : 0);
}
}
/**
* @dev Return the log in base 256, rounded down, of a positive value.
* Returns 0 if given 0.
*
* Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
*/
function log256(uint256 value) internal pure returns (uint256) {
uint256 result = 0;
unchecked {
if (value >> 128 > 0) {
value >>= 128;
result += 16;
}
if (value >> 64 > 0) {
value >>= 64;
result += 8;
}
if (value >> 32 > 0) {
value >>= 32;
result += 4;
}
if (value >> 16 > 0) {
value >>= 16;
result += 2;
}
if (value >> 8 > 0) {
result += 1;
}
}
return result;
}
/**
* @dev Return the log in base 256, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/
function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
unchecked {
uint256 result = log256(value);
return result + (rounding == Rounding.Up && 1 << (result << 3) < value ? 1 : 0);
}
}
}
struct VaultAccount {
uint128 amount; // Total amount, analogous to market cap
uint128 shares; // Total shares, analogous to shares outstanding
}
interface ISturdyPair {
struct CurrentRateInfo {
uint32 lastBlock;
uint32 feeToProtocolRate; // Fee amount 1e5 precision
uint64 lastTimestamp;
uint64 ratePerSec;
uint64 fullUtilizationRate;
}
function CIRCUIT_BREAKER_ADDRESS() external view returns (address);
function COMPTROLLER_ADDRESS() external view returns (address);
function DEPLOYER_ADDRESS() external view returns (address);
function FRAXLEND_WHITELIST_ADDRESS() external view returns (address);
function timelockAddress() external view returns (address);
function addCollateral(uint256 _collateralAmount, address _borrower) external;
function addInterest(
bool _returnAccounting
)
external
returns (
uint256 _interestEarned,
uint256 _feesAmount,
uint256 _feesShare,
CurrentRateInfo memory _currentRateInfo,
VaultAccount memory _totalAsset,
VaultAccount memory _totalBorrow
);
function allowance(address owner, address spender) external view returns (uint256);
function approve(address spender, uint256 amount) external returns (bool);
function approvedBorrowers(address) external view returns (bool);
function approvedLenders(address) external view returns (bool);
function approveBorrowDelegation(address _delegatee, uint256 _amount) external;
function asset() external view returns (address);
function balanceOf(address account) external view returns (uint256);
function borrowAsset(
uint256 _borrowAmount,
uint256 _collateralAmount,
address _receiver
) external returns (uint256 _shares);
function borrowAssetOnBehalfOf(
uint256 _borrowAmount,
address _onBehalfOf
) external returns (uint256 _shares);
function borrowerWhitelistActive() external view returns (bool);
function changeFee(uint32 _newFee) external;
function cleanLiquidationFee() external view returns (uint256);
function collateralContract() external view returns (address);
function currentRateInfo()
external
view
returns (
uint32 lastBlock,
uint32 feeToProtocolRate,
uint64 lastTimestamp,
uint64 ratePerSec,
uint64 fullUtilizationRate
);
function decimals() external view returns (uint8);
function decreaseAllowance(address spender, uint256 subtractedValue) external returns (bool);
function deposit(uint256 _amount, address _receiver) external returns (uint256 _sharesReceived);
function dirtyLiquidationFee() external view returns (uint256);
function exchangeRateInfo() external view returns (address oracle, uint32 maxOracleDeviation, uint184 lastTimestamp, uint256 lowExchangeRate, uint256 highExchangeRate);
function getConstants()
external
pure
returns (
uint256 _LTV_PRECISION,
uint256 _LIQ_PRECISION,
uint256 _UTIL_PREC,
uint256 _FEE_PRECISION,
uint256 _EXCHANGE_PRECISION,
uint256 _DEVIATION_PRECISION,
uint256 _RATE_PRECISION,
uint256 _MAX_PROTOCOL_FEE
);
function getImmutableAddressBool()
external
view
returns (
address _assetContract,
address _collateralContract,
address _oracleMultiply,
address _oracleDivide,
address _rateContract,
address _DEPLOYER_CONTRACT,
address _COMPTROLLER_ADDRESS,
address _FRAXLEND_WHITELIST,
bool _borrowerWhitelistActive,
bool _lenderWhitelistActive
);
function getImmutableUint256()
external
view
returns (
uint256 _oracleNormalization,
uint256 _maxLTV,
uint256 _cleanLiquidationFee,
uint256 _maturityDate,
uint256 _penaltyRate
);
function getPairAccounting()
external
view
returns (
uint128 _totalAssetAmount,
uint128 _totalAssetShares,
uint128 _totalBorrowAmount,
uint128 _totalBorrowShares,
uint256 _totalCollateral
);
function getUserSnapshot(
address _address
) external view returns (uint256 _userAssetShares, uint256 _userBorrowShares, uint256 _userCollateralBalance);
function increaseAllowance(address spender, uint256 addedValue) external returns (bool);
function lenderWhitelistActive() external view returns (bool);
function leveragedPosition(
address _swapperAddress,
uint256 _borrowAmount,
uint256 _initialCollateralAmount,
uint256 _amountCollateralOutMin,
address[] memory _path
) external returns (uint256 _totalCollateralBalance);
function liquidate(
uint128 _sharesToLiquidate,
uint256 _deadline,
address _borrower
) external returns (uint256 _collateralForLiquidator);
function maturityDate() external view returns (uint256);
function maxLTV() external view returns (uint256);
function maxOracleDelay() external view returns (uint256);
function name() external view returns (string memory);
function oracleDivide() external view returns (address);
function oracleMultiply() external view returns (address);
function oracleNormalization() external view returns (uint256);
function owner() external view returns (address);
function pause() external;
function paused() external view returns (bool);
function penaltyRate() external view returns (uint256);
function rateContract() external view returns (address);
function redeem(uint256 _shares, address _receiver, address _owner) external returns (uint256 _amountToReturn);
function removeCollateral(uint256 _collateralAmount, address _receiver) external;
function removeCollateralFrom(
uint256 _collateralAmount,
address _receiver,
address _borrower
) external;
function setWhitelistedDelegators(address _delegator, bool _enabled) external;
function renounceOwnership() external;
function repayAsset(uint256 _shares, address _borrower) external returns (uint256 _amountToRepay);
function repayAssetWithCollateral(
address _swapperAddress,
uint256 _collateralToSwap,
uint256 _amountAssetOutMin,
address[] memory _path
) external returns (uint256 _amountAssetOut);
function setApprovedBorrowers(address[] memory _borrowers, bool _approval) external;
function setApprovedLenders(address[] memory _lenders, bool _approval) external;
function setMaxOracleDelay(uint256 _newDelay) external;
function setSwapper(address _swapper, bool _approval) external;
function setTimelock(address _newAddress) external;
function swappers(address) external view returns (bool);
function symbol() external view returns (string memory);
function toAssetAmount(
uint256 _shares,
bool _roundUp,
bool _previewInterest
) external view returns (uint256);
function toAssetShares(
uint256 _amount,
bool _roundUp,
bool _previewInterest
) external view returns (uint256);
function toBorrowAmount(
uint256 _shares,
bool _roundUp,
bool _previewInterest
) external view returns (uint256 _amount);
function toBorrowShares(
uint256 _amount,
bool _roundUp,
bool _previewInterest
) external view returns (uint256 _shares);
function totalAsset() external view returns (uint128 amount, uint128 shares);
function totalBorrow() external view returns (uint128 amount, uint128 shares);
function totalCollateral() external view returns (uint256);
function totalSupply() external view returns (uint256);
function transfer(address to, uint256 amount) external returns (bool);
function transferFrom(address from, address to, uint256 amount) external returns (bool);
function transferOwnership(address newOwner) external;
function unpause() external;
function updateExchangeRate()
external
returns (bool _isBorrowAllowed, uint256 _lowExchangeRate, uint256 _highExchangeRate);
function userBorrowShares(address) external view returns (uint256);
function userCollateralBalance(address) external view returns (uint256);
function version() external pure returns (uint256 _major, uint256 _minor, uint256 _patch);
function withdrawFees(uint128 _shares, address _recipient) external returns (uint256 _amountToTransfer);
function isInterestPaused() external view returns (bool);
}
contract SturdySiloStrategy is BaseStrategy {
using SafeERC20 for ERC20;
ISturdyPair public immutable pair;
// Amount of deposits we need before depositing
uint256 public immutable depositThreshold;
// Bool if we have met the depositThreshold
bool public thresholdMet;
// Timestamp of when withdraws will be enabled
uint256 public timeToUnlock;
// If the timeToUnlock is still able to be set. (false == can still be set.)
bool public freezeTimeToUnlock;
constructor(
address _asset,
address _pair,
string memory _name,
uint256 _depositThreshold,
uint256 _timeToUnlock
) BaseStrategy(_asset, _name) {
// Set pair address
pair = ISturdyPair(_pair);
// Set depositThreshold value
depositThreshold = _depositThreshold;
// Set initial time to unlock
timeToUnlock = _timeToUnlock;
// Approve the pair for FRAX
ERC20(_asset).safeApprove(address(pair), type(uint256).max);
}
/*//////////////////////////////////////////////////////////////
NEEDED TO BE OVERRIDEN BY STRATEGIST
//////////////////////////////////////////////////////////////*/
/**
* @dev Should deploy up to '_amount' of 'asset' in the yield source.
*
* This function is called at the end of a {deposit} or {mint}
* call. Meaning that unless a whitelist is implemented it will
* be entirely permsionless and thus can be sandwhiched or otherwise
* manipulated.
*
* @param _amount The amount of 'asset' that the strategy should attemppt
* to deposit in the yield source.
*/
function _deployFunds(uint256 _amount) internal override {
// We don't deposit until the threshold is met.
if (thresholdMet) {
pair.deposit(_amount, address(this));
// Amount will include all idle funds if not deposited yet.
} else if (_amount > depositThreshold) {
// Set the bool for easy checks in the future.
thresholdMet = true;
pair.deposit(_amount, address(this));
}
}
/**
* @dev Will attempt to free the '_amount' of 'asset'.
*
* The amount of 'asset' that is already loose has already
* been accounted for.
*
* This function is called during {withdraw} and {redeem} calls.
* Meaning that unless a whitelist is implemented it will be
* entirely permsionless and thus can be sandwhiched or otherwise
* manipulated.
*
* Should not rely on asset.balanceOf(address(this)) calls other than
* for diff accounting puroposes.
*
* Any difference between `_amount` and what is actually freed will be
* counted as a loss and passed on to the withdrawer. This means
* care should be taken in times of illiquidity. It may be better to revert
* if withdraws are simply illiquid so not to realize incorrect losses.
*
* @param _amount, The amount of 'asset' to be freed.
*/
function _freeFunds(uint256 _amount) internal override {
// Only proccess withdraws if we have unlocked the stratey
if (block.timestamp >= timeToUnlock) {
// Accrue interest for conversion.
pair.addInterest(false);
pair.redeem(
pair.toAssetShares(_amount, false, false),
address(this),
address(this)
);
} else {
// This should never happen but we check just in case and
// revert so we don't record an incorrect loss.
require(false, "Locked!");
}
}
/**
* @dev Internal function to harvest all rewards, redeploy any idle
* funds and return an accurate accounting of all funds currently
* held by the Strategy.
*
* This should do any needed harvesting, rewards selling, accrual,
* redepositing etc. to get the most accurate view of current assets.
*
* NOTE: All applicable assets including loose assets should be
* accounted for in this function.
*
* Care should be taken when relying on oracles or swap values rather
* than actual amounts as all Strategy profit/loss accounting will
* be done based on this returned value.
*
* This can still be called post a shutdown, a strategist can check
* `TokenizedStrategy.isShutdown()` to decide if funds should be
* redeployed or simply realize any profits/losses.
*
* @return _totalAssets A trusted and accurate account for the total
* amount of 'asset' the strategy currently holds including idle funds.
*/
function _harvestAndReport()
internal
override
returns (uint256 _totalAssets)
{
// Acccrue interest
pair.addInterest(false);
_totalAssets =
// Return total balance including idle.
asset.balanceOf(address(this)) +
pair.toAssetAmount(pair.balanceOf(address(this)), false, false);
}
/*//////////////////////////////////////////////////////////////
OPTIONAL TO OVERRIDE BY STRATEGIST
//////////////////////////////////////////////////////////////*/
/**
* @notice Gets the max amount of `asset` that can be withdrawn.
* @dev Defaults to an unlimited amount for any address. But can
* be overriden by strategists.
*
* This function will be called before any withdraw or redeem to enforce
* any limits desired by the strategist. This can be used for illiquid
* or sandwhichable strategies. It should never be lower than `totalIdle`.
*
* EX:
* return TokenIzedStrategy.totalIdle();
*
* This does not need to take into account the `_owner`'s share balance
* or conversion rates from shares to assets.
*
* @param . The address that is withdrawing from the strategy.
* @return . The avialable amount that can be withdrawn in terms of `asset`
*/
function availableWithdrawLimit(
address _owner
) public view override returns (uint256) {
// If we have passed the unlock time we have no limit.
if (block.timestamp >= timeToUnlock) {
return
TokenizedStrategy.totalIdle() +
asset.balanceOf(address(pair));
} else {
// Otherwise just the amount of idle can be withdrawn.
return TokenizedStrategy.totalIdle();
}
}
/**
* @dev Optional function for a strategist to override that will
* allow management to manually withdraw deployed funds from the
* yield source if a strategy is shutdown.
*
* This should attempt to free `_amount`, noting that `_amount` may
* be more than is currently deployed.
*
* NOTE: This will not realize any profits or losses. A seperate
* {report} will be needed in order to record any profit/loss. If
* a report may need to be called after a shutdown it is important
* to check if the strategy is shutdown during {_harvestAndReport}
* so that it does not simply re-deploy all funds that had been freed.
*
* EX:
* if(freeAsset > 0 && !TokenizedStrategy.isShutdown()) {
* depositFunds...
* }
*
* @param _amount The amount of asset to attempt to free.
*/
function _emergencyWithdraw(uint256 _amount) internal override {
pair.addInterest(false);
// Round up and check against actual balance
uint256 shares = pair.toAssetShares(_amount, true, false);
shares = Math.min(shares, pair.balanceOf(address(this)));
pair.redeem(shares, address(this), address(this));
}
// Management can update the unlock time unless it has been frozen.
function setTimeToUnlock(uint256 _newTime) external onlyManagement {
require(!freezeTimeToUnlock, "lock frozen");
timeToUnlock = _newTime;
}
// One way switch to freeze the unlock time.
function freezeUnlock() external onlyManagement {
freezeTimeToUnlock = true;
}
function maxLTV() external view override returns (uint256) {
return pair.maxLTV();
}
function collateral() external view override returns (address) {
return pair.collateralContract();
}
}