// SPDX-License-Identifier: AGPL-3.0
pragma solidity 0.8.18;
// We use the Tokenized Strategy interface.
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/ERC20.sol)
// 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 (last updated v4.9.4) (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;
}
function _contextSuffixLength() internal view virtual returns (uint256) {
return 0;
}
}
/**
* @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.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
* to implement supply mechanisms].
*
* The default value of {decimals} is 18. To change this, you should override
* this function so it returns a different value.
*
* 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}.
*
* 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 {}
}
// OpenZeppelin Contracts (last updated v4.9.0) (interfaces/IERC4626.sol)
/**
* @dev Interface of the ERC4626 "Tokenized Vault Standard", as defined in
* https://eips.ethereum.org/EIPS/eip-4626[ERC-4626].
*
* _Available since v4.7._
*/
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 v4.9.4) (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.
*
* ==== Security Considerations
*
* There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
* expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
* considered as an intention to spend the allowance in any specific way. The second is that because permits have
* built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
* take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
* generally recommended is:
*
* ```solidity
* function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
* try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
* doThing(..., value);
* }
*
* function doThing(..., uint256 value) public {
* token.safeTransferFrom(msg.sender, address(this), value);
* ...
* }
* ```
*
* Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
* `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
* {SafeERC20-safeTransferFrom}).
*
* Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
* contracts should have entry points that don't rely on permit.
*/
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].
*
* CAUTION: See Security Considerations above.
*/
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 that implements the 4626 standard and the implementation functions
interface ITokenizedStrategy is IERC4626, IERC20Permit {
/*//////////////////////////////////////////////////////////////
EVENTS
//////////////////////////////////////////////////////////////*/
event StrategyShutdown();
event NewTokenizedStrategy(
address indexed strategy,
address indexed asset,
string apiVersion
);
event Reported(
uint256 profit,
uint256 loss,
uint256 protocolFees,
uint256 performanceFees
);
event UpdatePerformanceFeeRecipient(
address indexed newPerformanceFeeRecipient
);
event UpdateKeeper(address indexed newKeeper);
event UpdatePerformanceFee(uint16 newPerformanceFee);
event UpdateManagement(address indexed newManagement);
event UpdateEmergencyAdmin(address indexed newEmergencyAdmin);
event UpdateProfitMaxUnlockTime(uint256 newProfitMaxUnlockTime);
event UpdatePendingManagement(address indexed newPendingManagement);
/*//////////////////////////////////////////////////////////////
INITIALIZATION
//////////////////////////////////////////////////////////////*/
function initialize(
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);
function maxWithdraw(
address owner,
uint256 /*maxLoss*/
) external view returns (uint256);
function maxRedeem(
address owner,
uint256 /*maxLoss*/
) external view returns (uint256);
/*//////////////////////////////////////////////////////////////
MODIFIER HELPERS
//////////////////////////////////////////////////////////////*/
function requireManagement(address _sender) external view;
function requireKeeperOrManagement(address _sender) external view;
function requireEmergencyAuthorized(address _sender) external view;
/*//////////////////////////////////////////////////////////////
KEEPERS FUNCTIONS
//////////////////////////////////////////////////////////////*/
function tend() external;
function report() external returns (uint256 _profit, uint256 _loss);
/*//////////////////////////////////////////////////////////////
CONSTANTS
//////////////////////////////////////////////////////////////*/
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 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 setName(string calldata _newName) external;
function shutdownStrategy() external;
function emergencyWithdraw(uint256 _amount) external;
}
interface IBaseStrategy {
function tokenizedStrategyAddress() external view returns (address);
/*//////////////////////////////////////////////////////////////
IMMUTABLE FUNCTIONS
//////////////////////////////////////////////////////////////*/
function availableDepositLimit(
address _owner
) external view returns (uint256);
function availableWithdrawLimit(
address _owner
) external view returns (uint256);
function deployFunds(uint256 _assets) external;
function freeFunds(uint256 _amount) external;
function harvestAndReport() external returns (uint256);
function tendThis(uint256 _totalIdle) external;
function shutdownWithdraw(uint256 _amount) external;
function tendTrigger() external view returns (bool, bytes memory);
}
interface IStrategy is IBaseStrategy, ITokenizedStrategy {}
// TokenizedStrategy interface used for internal view delegateCalls.
/**
* @title YearnV3 Base Strategy
* @author yearn.finance
* @notice
* BaseStrategy implements all of the required functionality to
* seamlessly integrate with the `TokenizedStrategy` implementation contract
* allowing anyone to easily build a fully permissionless ERC-4626 compliant
* Vault by inheriting this contract and overriding three simple functions.
* It utilizes an immutable proxy pattern that allows the BaseStrategy
* to remain simple and small. All standard logic is held within the
* `TokenizedStrategy` and is reused over any n strategies all using the
* `fallback` function to delegatecall the implementation so that strategists
* can only be concerned with writing their strategy specific code.
*
* This contract should be inherited and the three main abstract methods
* `_deployFunds`, `_freeFunds` and `_harvestAndReport` implemented to adapt
* the Strategy to the particular needs it has to generate yield. There are
* other optional methods that can be implemented to further customize
* the strategy if desired.
*
* All default storage for the strategy is controlled and updated by the
* `TokenizedStrategy`. The implementation holds a storage struct that
* contains all needed global variables in a manual storage slot. This
* means strategists can feel free to implement their own custom storage
* variables as they need with no concern of collisions. All global variables
* can be viewed within the Strategy by a simple call using the
* `TokenizedStrategy` variable. IE: TokenizedStrategy.globalVariable();.
*/
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.requireManagement(msg.sender);
_;
}
/**
* @dev Use to assure that the call is coming from either the strategies
* management or the keeper.
*/
modifier onlyKeepers() {
TokenizedStrategy.requireKeeperOrManagement(msg.sender);
_;
}
/**
* @dev Use to assure that the call is coming from either the strategies
* management or the emergency admin.
*/
modifier onlyEmergencyAuthorized() {
TokenizedStrategy.requireEmergencyAuthorized(msg.sender);
_;
}
/**
* @dev Require that the msg.sender is this address.
*/
function _onlySelf() internal view {
require(msg.sender == address(this), "!self");
}
/*//////////////////////////////////////////////////////////////
CONSTANTS
//////////////////////////////////////////////////////////////*/
/**
* @dev 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 =
0x254A93feff3BEeF9cA004E913bB5443754e8aB19;
/*//////////////////////////////////////////////////////////////
IMMUTABLES
//////////////////////////////////////////////////////////////*/
/**
* @dev Underlying asset the Strategy is earning yield on.
* Stored here for cheap retrievals within the strategy.
*/
ERC20 internal immutable asset;
/**
* @dev 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;
/**
* @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.initialize,
(_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 Can 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 can attempt
* to deposit in the yield source.
*/
function _deployFunds(uint256 _amount) internal virtual;
/**
* @dev Should attempt to free the '_amount' of 'asset'.
*
* NOTE: 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.
*
* This 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 Can 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 can
* attempt to deposit in the yield source.
*/
function deployFunds(uint256 _amount) external virtual onlySelf {
_deployFunds(_amount);
}
/**
* @notice Should 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.
* @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.
*
* @param _amount The amount of asset to attempt to free.
*/
function shutdownWithdraw(uint256 _amount) external virtual onlySelf {
_emergencyWithdraw(_amount);
}
/**
* @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;
}
/**
* @dev Execute a function on the TokenizedStrategy and return any value.
*
* This fallback function will be executed when any of the standard functions
* defined in the TokenizedStrategy are called since they wont be defined in
* this contract.
*
* It will delegatecall the TokenizedStrategy implementation with the exact
* calldata and return any relevant values.
*
*/
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())
}
}
}
}
/**
* @title Base Health Check
* @author Yearn.finance
* @notice This contract can be inherited by any Yearn
* V3 strategy wishing to implement a health check during
* the `report` function in order to prevent any unexpected
* behavior from being permanently recorded as well as the
* `checkHealth` modifier.
*
* A strategist simply needs to inherit this contract. Set
* the limit ratios to the desired amounts and then
* override `_harvestAndReport()` just as they otherwise
* would. If the profit or loss that would be recorded is
* outside the acceptable bounds the tx will revert.
*
* The healthcheck does not prevent a strategy from reporting
* losses, but rather can make sure manual intervention is
* needed before reporting an unexpected loss or profit.
*/
abstract contract BaseHealthCheck is BaseStrategy {
// Can be used to determine if a healthcheck should be called.
// Defaults to true;
bool public doHealthCheck = true;
uint256 internal constant MAX_BPS = 10_000;
// Default profit limit to 100%.
uint16 private _profitLimitRatio = uint16(MAX_BPS);
// Defaults loss limit to 0.
uint16 private _lossLimitRatio;
constructor(
address _asset,
string memory _name
) BaseStrategy(_asset, _name) {}
/**
* @notice Returns the current profit limit ratio.
* @dev Use a getter function to keep the variable private.
* @return . The current profit limit ratio.
*/
function profitLimitRatio() public view returns (uint256) {
return _profitLimitRatio;
}
/**
* @notice Returns the current loss limit ratio.
* @dev Use a getter function to keep the variable private.
* @return . The current loss limit ratio.
*/
function lossLimitRatio() public view returns (uint256) {
return _lossLimitRatio;
}
/**
* @notice Set the `profitLimitRatio`.
* @dev Denominated in basis points. I.E. 1_000 == 10%.
* @param _newProfitLimitRatio The mew profit limit ratio.
*/
function setProfitLimitRatio(
uint256 _newProfitLimitRatio
) external onlyManagement {
_setProfitLimitRatio(_newProfitLimitRatio);
}
/**
* @dev Internally set the profit limit ratio. Denominated
* in basis points. I.E. 1_000 == 10%.
* @param _newProfitLimitRatio The mew profit limit ratio.
*/
function _setProfitLimitRatio(uint256 _newProfitLimitRatio) internal {
require(_newProfitLimitRatio > 0, "!zero profit");
require(_newProfitLimitRatio <= type(uint16).max, "!too high");
_profitLimitRatio = uint16(_newProfitLimitRatio);
}
/**
* @notice Set the `lossLimitRatio`.
* @dev Denominated in basis points. I.E. 1_000 == 10%.
* @param _newLossLimitRatio The new loss limit ratio.
*/
function setLossLimitRatio(
uint256 _newLossLimitRatio
) external onlyManagement {
_setLossLimitRatio(_newLossLimitRatio);
}
/**
* @dev Internally set the loss limit ratio. Denominated
* in basis points. I.E. 1_000 == 10%.
* @param _newLossLimitRatio The new loss limit ratio.
*/
function _setLossLimitRatio(uint256 _newLossLimitRatio) internal {
require(_newLossLimitRatio < MAX_BPS, "!loss limit");
_lossLimitRatio = uint16(_newLossLimitRatio);
}
/**
* @notice Turns the healthcheck on and off.
* @dev If turned off the next report will auto turn it back on.
* @param _doHealthCheck Bool if healthCheck should be done.
*/
function setDoHealthCheck(bool _doHealthCheck) public onlyManagement {
doHealthCheck = _doHealthCheck;
}
/**
* @notice OVerrides the default {harvestAndReport} to include a healthcheck.
* @return _totalAssets New totalAssets post report.
*/
function harvestAndReport()
external
override
onlySelf
returns (uint256 _totalAssets)
{
// Let the strategy report.
_totalAssets = _harvestAndReport();
// Run the healthcheck on the amount returned.
_executeHealthCheck(_totalAssets);
}
/**
* @dev To be called during a report to make sure the profit
* or loss being recorded is within the acceptable bound.
*
* @param _newTotalAssets The amount that will be reported.
*/
function _executeHealthCheck(uint256 _newTotalAssets) internal virtual {
if (!doHealthCheck) {
doHealthCheck = true;
return;
}
// Get the current total assets from the implementation.
uint256 currentTotalAssets = TokenizedStrategy.totalAssets();
if (_newTotalAssets > currentTotalAssets) {
require(
((_newTotalAssets - currentTotalAssets) <=
(currentTotalAssets * uint256(_profitLimitRatio)) /
MAX_BPS),
"healthCheck"
);
} else if (currentTotalAssets > _newTotalAssets) {
require(
(currentTotalAssets - _newTotalAssets <=
((currentTotalAssets * uint256(_lossLimitRatio)) /
MAX_BPS)),
"healthCheck"
);
}
}
}
// OpenZeppelin Contracts (last updated v4.9.0) (utils/math/Math.sol)
/**
* @dev Standard math utilities missing in the Solidity language.
*/
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);
}
}
}
// OpenZeppelin Contracts (last updated v4.9.3) (token/ERC20/utils/SafeERC20.sol)
// 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);
}
}
}
/**
* @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;
/**
* @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));
}
}
/**
* @title Base4626Compounder
* @dev Can be used to make a simple strategy that compounds
* rewards for any 4626 vault.
*/
contract Base4626Compounder is BaseHealthCheck {
using SafeERC20 for ERC20;
IStrategy public immutable vault;
constructor(
address _asset,
string memory _name,
address _vault
) BaseHealthCheck(_asset, _name) {
require(IStrategy(_vault).asset() == _asset, "wrong vault");
vault = IStrategy(_vault);
asset.safeApprove(_vault, type(uint256).max);
}
/*//////////////////////////////////////////////////////////////
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 override {
vault.deposit(_amount, address(this));
_stake();
}
/**
* @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 override {
// Use previewWithdraw to round up.
uint256 shares = vault.previewWithdraw(_amount);
uint256 vaultBalance = balanceOfVault();
if (shares > vaultBalance) {
unchecked {
_unStake(shares - vaultBalance);
}
shares = Math.min(shares, balanceOfVault());
}
vault.redeem(shares, address(this), address(this));
}
/**
* @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
override
returns (uint256 _totalAssets)
{
// Claim and sell any rewards.
_claimAndSellRewards();
// Return total balance
_totalAssets = balanceOfAsset() + valueOfVault();
}
/**
* @dev Override to stake loose vault tokens after they
* are deposited to the `vault`.
*/
function _stake() internal virtual {}
/**
* @dev If vault tokens are staked, override to unstake them before
* any withdraw or redeems.
* @param _amount The amount of vault tokens to unstake.
*/
function _unStake(uint256 _amount) internal virtual {}
/**
* @dev Called during reports to do any harvesting of rewards needed.
*/
function _claimAndSellRewards() internal virtual {}
/**
* @notice Return the current loose balance of this strategies `asset`.
*/
function balanceOfAsset() public view virtual returns (uint256) {
return asset.balanceOf(address(this));
}
/**
* @notice Return the current balance of the strategies vault shares.
*/
function balanceOfVault() public view virtual returns (uint256) {
return vault.balanceOf(address(this));
}
/**
* @notice If the vaults tokens are staked. To override and return the
* amount of vault tokens the strategy has staked.
*/
function balanceOfStake() public view virtual returns (uint256) {}
/**
* @notice The full value denominated in `asset` of the strategies vault
* tokens held both in the contract and staked.
*/
function valueOfVault() public view virtual returns (uint256) {
return vault.convertToAssets(balanceOfVault() + balanceOfStake());
}
/**
* @notice The max amount of `asset` than can be redeemed from the vault.
* @dev If the vault tokens are staked this needs to include the
* vault.maxRedeem(stakingContract) to be accurate.
*
* NOTE: This should use vault.convertToAssets(vault.maxRedeem(address));
* rather than vault.maxWithdraw(address);
*/
function vaultsMaxWithdraw() public view virtual returns (uint256) {
return vault.convertToAssets(vault.maxRedeem(address(this)));
}
/**
* @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
) public view virtual override returns (uint256) {
// Return the max amount the vault will allow for deposits.
return vault.maxDeposit(address(this));
}
/**
* @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
) public view virtual override returns (uint256) {
// Return the loose balance of asset and the max we can withdraw from the vault
return balanceOfAsset() + vaultsMaxWithdraw();
}
/**
* @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 override {
_freeFunds(Math.min(_amount, vaultsMaxWithdraw()));
}
}
interface IStaking {
function stakingToken() external view returns (address);
function rewardsToken() external view returns (address);
function paused() external view returns (bool);
function earned(address) external view returns (uint256);
function stake(uint256 _amount, uint16 _referral) external;
function withdraw(uint256 _amount) external;
function getReward() external;
}
interface IReferral{
function deposit(uint256, address, uint16) external;
}
/// @title yearn-v3-SkyLender
/// @author mil0x
/// @notice yearn v3 Strategy that lends USDS to sUSDS.
contract SkyLender is Base4626Compounder {
using SafeERC20 for ERC20;
///@notice Mapping of addresses that are allowed to deposit.
mapping(address => bool) public allowed;
///@notice yearn's referral code
uint16 public referral = 13425;
///@notice yearn governance
address public constant GOV = 0xFEB4acf3df3cDEA7399794D0869ef76A6EfAff52;
address private constant USDS = 0xdC035D45d973E3EC169d2276DDab16f1e407384F;
address private constant SUSDS = 0xa3931d71877C0E7a3148CB7Eb4463524FEc27fbD;
constructor(string memory _name) Base4626Compounder(USDS, _name, SUSDS) {
}
function _deployFunds(uint256 _amount) internal virtual override {
IReferral(address(vault)).deposit(_amount, address(this), referral);
}
function availableDepositLimit(address _owner) public view override returns (uint256) {
// If the owner is whitelisted, allow deposits.
if (allowed[_owner]) {
return type(uint256).max;
} else {
return 0;
}
}
/**
* @notice Set or update an addresses whitelist status.
* @param _address the address for which to change the whitelist status
* @param _allowed the bool to set as whitelisted (true) or not (false)
*/
function setAllowed(address _address, bool _allowed) external onlyManagement {
allowed[_address] = _allowed;
}
/**
* @notice Set the referral code for depositing.
* @param _referral uint16 referral code
*/
function setReferral(uint16 _referral) external onlyManagement {
referral = _referral;
}
/*//////////////////////////////////////////////////////////////
GOVERNANCE:
//////////////////////////////////////////////////////////////*/
/// @notice Sweep of non-asset ERC20 tokens to governance (onlyGovernance)
/// @param _token The ERC20 token to sweep
function sweep(address _token) external onlyGovernance {
require(_token != address(asset), "!asset");
require(_token != address(vault), "!vault");
ERC20(_token).safeTransfer(GOV, ERC20(_token).balanceOf(address(this)));
}
modifier onlyGovernance() {
require(msg.sender == GOV, "!gov");
_;
}
}
{
"compilationTarget": {
"SkyLender.sol": "SkyLender"
},
"evmVersion": "paris",
"libraries": {},
"metadata": {
"bytecodeHash": "ipfs"
},
"optimizer": {
"enabled": true,
"runs": 200
},
"remappings": []
}
[{"inputs":[{"internalType":"string","name":"_name","type":"string"}],"stateMutability":"nonpayable","type":"constructor"},{"stateMutability":"nonpayable","type":"fallback"},{"inputs":[],"name":"GOV","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"","type":"address"}],"name":"allowed","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"_owner","type":"address"}],"name":"availableDepositLimit","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"","type":"address"}],"name":"availableWithdrawLimit","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"balanceOfAsset","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"balanceOfStake","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"balanceOfVault","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"_amount","type":"uint256"}],"name":"deployFunds","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"doHealthCheck","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"_amount","type":"uint256"}],"name":"freeFunds","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"harvestAndReport","outputs":[{"internalType":"uint256","name":"_totalAssets","type":"uint256"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"lossLimitRatio","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"profitLimitRatio","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"referral","outputs":[{"internalType":"uint16","name":"","type":"uint16"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"_address","type":"address"},{"internalType":"bool","name":"_allowed","type":"bool"}],"name":"setAllowed","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"bool","name":"_doHealthCheck","type":"bool"}],"name":"setDoHealthCheck","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_newLossLimitRatio","type":"uint256"}],"name":"setLossLimitRatio","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_newProfitLimitRatio","type":"uint256"}],"name":"setProfitLimitRatio","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint16","name":"_referral","type":"uint16"}],"name":"setReferral","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_amount","type":"uint256"}],"name":"shutdownWithdraw","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"_token","type":"address"}],"name":"sweep","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"_totalIdle","type":"uint256"}],"name":"tendThis","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"tendTrigger","outputs":[{"internalType":"bool","name":"","type":"bool"},{"internalType":"bytes","name":"","type":"bytes"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"tokenizedStrategyAddress","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"valueOfVault","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"vault","outputs":[{"internalType":"contract IStrategy","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"vaultsMaxWithdraw","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"}]