Contract Source Code:
File 1 of 1 : LoanToken
/**
* Copyright 2017-2020, bZeroX, LLC <https://bzx.network/>. All Rights Reserved.
* Licensed under the Apache License, Version 2.0.
*/
pragma solidity 0.5.17;
interface IWeth {
function deposit() external payable;
function withdraw(uint256 wad) external;
}
contract IERC20 {
string public name;
uint8 public decimals;
string public symbol;
function totalSupply() public view returns (uint256);
function balanceOf(address _who) public view returns (uint256);
function allowance(address _owner, address _spender) public view returns (uint256);
function approve(address _spender, uint256 _value) public returns (bool);
function transfer(address _to, uint256 _value) public returns (bool);
function transferFrom(address _from, address _to, uint256 _value) public returns (bool);
event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(address indexed owner, address indexed spender, uint256 value);
}
contract IWethERC20 is IWeth, IERC20 {}
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return sub(a, b, "SafeMath: subtraction overflow");
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*
* _Available since v2.4.0._
*/
function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b <= a, errorMessage);
uint256 c = a - b;
return c;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return div(a, b, "SafeMath: division by zero");
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts with custom message on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*
* _Available since v2.4.0._
*/
function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
// Solidity only automatically asserts when dividing by 0
require(b != 0, errorMessage);
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Integer division of two numbers, rounding up and truncating the quotient
*/
function divCeil(uint256 a, uint256 b) internal pure returns (uint256) {
return divCeil(a, b, "SafeMath: division by zero");
}
/**
* @dev Integer division of two numbers, rounding up and truncating the quotient
*/
function divCeil(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
// Solidity only automatically asserts when dividing by 0
require(b != 0, errorMessage);
if (a == 0) {
return 0;
}
uint256 c = ((a - 1) / b) + 1;
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
return mod(a, b, "SafeMath: modulo by zero");
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts with custom message when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*
* _Available since v2.4.0._
*/
function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b != 0, errorMessage);
return a % b;
}
function min256(uint256 _a, uint256 _b) internal pure returns (uint256) {
return _a < _b ? _a : _b;
}
}
/**
* @title SignedSafeMath
* @dev Signed math operations with safety checks that revert on error.
*/
library SignedSafeMath {
int256 constant private _INT256_MIN = -2**255;
/**
* @dev Returns the multiplication of two signed integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
*
* - Multiplication cannot overflow.
*/
function mul(int256 a, int256 b) internal pure returns (int256) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
if (a == 0) {
return 0;
}
require(!(a == -1 && b == _INT256_MIN), "SignedSafeMath: multiplication overflow");
int256 c = a * b;
require(c / a == b, "SignedSafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two signed integers. Reverts on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(int256 a, int256 b) internal pure returns (int256) {
require(b != 0, "SignedSafeMath: division by zero");
require(!(b == -1 && a == _INT256_MIN), "SignedSafeMath: division overflow");
int256 c = a / b;
return c;
}
/**
* @dev Returns the subtraction of two signed integers, reverting on
* overflow.
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(int256 a, int256 b) internal pure returns (int256) {
int256 c = a - b;
require((b >= 0 && c <= a) || (b < 0 && c > a), "SignedSafeMath: subtraction overflow");
return c;
}
/**
* @dev Returns the addition of two signed integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
*
* - Addition cannot overflow.
*/
function add(int256 a, int256 b) internal pure returns (int256) {
int256 c = a + b;
require((b >= 0 && c >= a) || (b < 0 && c < a), "SignedSafeMath: addition overflow");
return c;
}
}
/**
* @title Helps contracts guard against reentrancy attacks.
* @author Remco Bloemen <remco@2π.com>, Eenae <[email protected]>
* @dev If you mark a function `nonReentrant`, you should also
* mark it `external`.
*/
contract ReentrancyGuard {
/// @dev Constant for unlocked guard state - non-zero to prevent extra gas costs.
/// See: https://github.com/OpenZeppelin/openzeppelin-solidity/issues/1056
uint256 internal constant REENTRANCY_GUARD_FREE = 1;
/// @dev Constant for locked guard state
uint256 internal constant REENTRANCY_GUARD_LOCKED = 2;
/**
* @dev We use a single lock for the whole contract.
*/
uint256 internal reentrancyLock = REENTRANCY_GUARD_FREE;
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* If you mark a function `nonReentrant`, you should also
* mark it `external`. Calling one `nonReentrant` function from
* another is not supported. Instead, you can implement a
* `private` function doing the actual work, and an `external`
* wrapper marked as `nonReentrant`.
*/
modifier nonReentrant() {
require(reentrancyLock == REENTRANCY_GUARD_FREE, "nonReentrant");
reentrancyLock = REENTRANCY_GUARD_LOCKED;
_;
reentrancyLock = REENTRANCY_GUARD_FREE;
}
}
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*/
function isContract(address account) internal view returns (bool) {
// According to EIP-1052, 0x0 is the value returned for not-yet created accounts
// and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
// for accounts without code, i.e. `keccak256('')`
bytes32 codehash;
bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
// solhint-disable-next-line no-inline-assembly
assembly { codehash := extcodehash(account) }
return (codehash != accountHash && codehash != 0x0);
}
/**
* @dev Converts an `address` into `address payable`. Note that this is
* simply a type cast: the actual underlying value is not changed.
*
* _Available since v2.4.0._
*/
function toPayable(address account) internal pure returns (address payable) {
return address(uint160(account));
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*
* _Available since v2.4.0._
*/
function sendValue(address recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
// solhint-disable-next-line avoid-call-value
(bool success, ) = recipient.call.value(amount)("");
require(success, "Address: unable to send value, recipient may have reverted");
}
}
/*
* @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 GSN 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.
*/
contract Context {
// Empty internal constructor, to prevent people from mistakenly deploying
// an instance of this contract, which should be used via inheritance.
constructor () internal { }
// solhint-disable-previous-line no-empty-blocks
function _msgSender() internal view returns (address payable) {
return msg.sender;
}
function _msgData() internal view returns (bytes memory) {
this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
return msg.data;
}
}
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor () internal {
address msgSender = _msgSender();
_owner = msgSender;
emit OwnershipTransferred(address(0), msgSender);
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(isOwner(), "unauthorized");
_;
}
/**
* @dev Returns true if the caller is the current owner.
*/
function isOwner() public view returns (bool) {
return _msgSender() == _owner;
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public onlyOwner {
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
*/
function _transferOwnership(address newOwner) internal {
require(newOwner != address(0), "Ownable: new owner is the zero address");
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
contract Pausable {
// keccak256("Pausable_FunctionPause")
bytes32 internal constant Pausable_FunctionPause = 0xa7143c84d793a15503da6f19bf9119a2dac94448ca45d77c8bf08f57b2e91047;
modifier pausable(bytes4 sig) {
require(!_isPaused(sig), "unauthorized");
_;
}
function _isPaused(
bytes4 sig)
internal
view
returns (bool isPaused)
{
bytes32 slot = keccak256(abi.encodePacked(sig, Pausable_FunctionPause));
assembly {
isPaused := sload(slot)
}
}
}
contract LoanTokenBase is ReentrancyGuard, Ownable, Pausable {
uint256 internal constant WEI_PRECISION = 10**18;
uint256 internal constant WEI_PERCENT_PRECISION = 10**20;
int256 internal constant sWEI_PRECISION = 10**18;
string public name;
string public symbol;
uint8 public decimals;
// uint88 for tight packing -> 8 + 88 + 160 = 256
uint88 internal lastSettleTime_;
address public loanTokenAddress;
uint256 public baseRate;
uint256 public rateMultiplier;
uint256 public lowUtilBaseRate;
uint256 public lowUtilRateMultiplier;
uint256 public targetLevel;
uint256 public kinkLevel;
uint256 public maxScaleRate;
uint256 internal _flTotalAssetSupply;
uint256 public checkpointSupply;
uint256 public initialPrice;
mapping (uint256 => bytes32) public loanParamsIds; // mapping of keccak256(collateralToken, isTorqueLoan) to loanParamsId
mapping (address => uint256) internal checkpointPrices_; // price of token at last user checkpoint
}
contract AdvancedTokenStorage is LoanTokenBase {
using SafeMath for uint256;
event Transfer(
address indexed from,
address indexed to,
uint256 value
);
event Approval(
address indexed owner,
address indexed spender,
uint256 value
);
event Mint(
address indexed minter,
uint256 tokenAmount,
uint256 assetAmount,
uint256 price
);
event Burn(
address indexed burner,
uint256 tokenAmount,
uint256 assetAmount,
uint256 price
);
mapping(address => uint256) internal balances;
mapping (address => mapping (address => uint256)) internal allowed;
uint256 internal totalSupply_;
function totalSupply()
public
view
returns (uint256)
{
return totalSupply_;
}
function balanceOf(
address _owner)
public
view
returns (uint256)
{
return balances[_owner];
}
function allowance(
address _owner,
address _spender)
public
view
returns (uint256)
{
return allowed[_owner][_spender];
}
}
contract LoanToken is AdvancedTokenStorage {
address internal target_;
constructor(
address _newOwner,
address _newTarget)
public
{
transferOwnership(_newOwner);
_setTarget(_newTarget);
}
function()
external
payable
{
if (gasleft() <= 2300) {
return;
}
address target = target_;
bytes memory data = msg.data;
assembly {
let result := delegatecall(gas, target, add(data, 0x20), mload(data), 0, 0)
let size := returndatasize
let ptr := mload(0x40)
returndatacopy(ptr, 0, size)
switch result
case 0 { revert(ptr, size) }
default { return(ptr, size) }
}
}
function setTarget(
address _newTarget)
public
onlyOwner
{
_setTarget(_newTarget);
}
function _setTarget(
address _newTarget)
internal
{
require(Address.isContract(_newTarget), "target not a contract");
target_ = _newTarget;
}
}