Contract Source Code:
File 1 of 1 : CDeployer
// File: contracts\libraries\SafeMath.sol
pragma solidity =0.5.16;
// From https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/math/Math.sol
// Subject to the MIT license.
/**
* @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 addition of two unsigned integers, reverting with custom message on overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, errorMessage);
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on underflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot underflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return sub(a, b, "SafeMath: subtraction underflow");
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on underflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot underflow.
*/
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 multiplication of two unsigned integers, reverting on overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b, string memory errorMessage) 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, errorMessage);
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.
*/
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 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.
*/
function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b != 0, errorMessage);
return a % b;
}
}
// File: contracts\ImpermaxERC20.sol
pragma solidity =0.5.16;
// This contract is basically UniswapV2ERC20 with small modifications
// src: https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/UniswapV2ERC20.sol
contract ImpermaxERC20 {
using SafeMath for uint;
string public name;
string public symbol;
uint8 public decimals = 18;
uint public totalSupply;
mapping(address => uint) public balanceOf;
mapping(address => mapping(address => uint)) public allowance;
bytes32 public DOMAIN_SEPARATOR;
mapping(address => uint) public nonces;
event Transfer(address indexed from, address indexed to, uint value);
event Approval(address indexed owner, address indexed spender, uint value);
constructor() public {}
function _setName(string memory _name, string memory _symbol) internal {
name = _name;
symbol = _symbol;
uint chainId;
assembly {
chainId := chainid
}
DOMAIN_SEPARATOR = keccak256(
abi.encode(
keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
keccak256(bytes(_name)),
keccak256(bytes("1")),
chainId,
address(this)
)
);
}
function _mint(address to, uint value) internal {
totalSupply = totalSupply.add(value);
balanceOf[to] = balanceOf[to].add(value);
emit Transfer(address(0), to, value);
}
function _burn(address from, uint value) internal {
balanceOf[from] = balanceOf[from].sub(value);
totalSupply = totalSupply.sub(value);
emit Transfer(from, address(0), value);
}
function _approve(address owner, address spender, uint value) private {
allowance[owner][spender] = value;
emit Approval(owner, spender, value);
}
function _transfer(address from, address to, uint value) internal {
balanceOf[from] = balanceOf[from].sub(value, "Impermax: TRANSFER_TOO_HIGH");
balanceOf[to] = balanceOf[to].add(value);
emit Transfer(from, to, value);
}
function approve(address spender, uint value) external returns (bool) {
_approve(msg.sender, spender, value);
return true;
}
function transfer(address to, uint value) external returns (bool) {
_transfer(msg.sender, to, value);
return true;
}
function transferFrom(address from, address to, uint value) external returns (bool) {
if (allowance[from][msg.sender] != uint(-1)) {
allowance[from][msg.sender] = allowance[from][msg.sender].sub(value, "Impermax: TRANSFER_NOT_ALLOWED");
}
_transfer(from, to, value);
return true;
}
function _checkSignature(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s, bytes32 typehash) internal {
require(deadline >= block.timestamp, "Impermax: EXPIRED");
bytes32 digest = keccak256(
abi.encodePacked(
'\x19\x01',
DOMAIN_SEPARATOR,
keccak256(abi.encode(typehash, owner, spender, value, nonces[owner]++, deadline))
)
);
address recoveredAddress = ecrecover(digest, v, r, s);
require(recoveredAddress != address(0) && recoveredAddress == owner, "Impermax: INVALID_SIGNATURE");
}
// keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external {
_checkSignature(owner, spender, value, deadline, v, r, s, PERMIT_TYPEHASH);
_approve(owner, spender, value);
}
}
// File: contracts\interfaces\IERC20.sol
pragma solidity >=0.5.0;
interface IERC20 {
event Approval(address indexed owner, address indexed spender, uint value);
event Transfer(address indexed from, address indexed to, uint value);
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view returns (uint8);
function totalSupply() external view returns (uint);
function balanceOf(address owner) external view returns (uint);
function allowance(address owner, address spender) external view returns (uint);
function approve(address spender, uint value) external returns (bool);
function transfer(address to, uint value) external returns (bool);
function transferFrom(address from, address to, uint value) external returns (bool);
}
// File: contracts\interfaces\IPoolToken.sol
pragma solidity >=0.5.0;
interface IPoolToken {
/*** Impermax ERC20 ***/
event Transfer(address indexed from, address indexed to, uint value);
event Approval(address indexed owner, address indexed spender, uint value);
function name() external pure returns (string memory);
function symbol() external pure returns (string memory);
function decimals() external pure returns (uint8);
function totalSupply() external view returns (uint);
function balanceOf(address owner) external view returns (uint);
function allowance(address owner, address spender) external view returns (uint);
function approve(address spender, uint value) external returns (bool);
function transfer(address to, uint value) external returns (bool);
function transferFrom(address from, address to, uint value) external returns (bool);
function DOMAIN_SEPARATOR() external view returns (bytes32);
function PERMIT_TYPEHASH() external pure returns (bytes32);
function nonces(address owner) external view returns (uint);
function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
/*** Pool Token ***/
event Mint(address indexed sender, address indexed minter, uint mintAmount, uint mintTokens);
event Redeem(address indexed sender, address indexed redeemer, uint redeemAmount, uint redeemTokens);
event Sync(uint totalBalance);
function underlying() external view returns (address);
function factory() external view returns (address);
function totalBalance() external view returns (uint);
function MINIMUM_LIQUIDITY() external pure returns (uint);
function exchangeRate() external returns (uint);
function mint(address minter) external returns (uint mintTokens);
function redeem(address redeemer) external returns (uint redeemAmount);
function skim(address to) external;
function sync() external;
function _setFactory() external;
}
// File: contracts\PoolToken.sol
pragma solidity =0.5.16;
contract PoolToken is IPoolToken, ImpermaxERC20 {
uint internal constant initialExchangeRate = 1e18;
address public underlying;
address public factory;
uint public totalBalance;
uint public constant MINIMUM_LIQUIDITY = 1000;
event Mint(address indexed sender, address indexed minter, uint mintAmount, uint mintTokens);
event Redeem(address indexed sender, address indexed redeemer, uint redeemAmount, uint redeemTokens);
event Sync(uint totalBalance);
/*** Initialize ***/
// called once by the factory
function _setFactory() external {
require(factory == address(0), "Impermax: FACTORY_ALREADY_SET");
factory = msg.sender;
}
/*** PoolToken ***/
function _update() internal {
totalBalance = IERC20(underlying).balanceOf(address(this));
emit Sync(totalBalance);
}
function exchangeRate() public returns (uint)
{
uint _totalSupply = totalSupply; // gas savings
uint _totalBalance = totalBalance; // gas savings
if (_totalSupply == 0 || _totalBalance == 0) return initialExchangeRate;
return _totalBalance.mul(1e18).div(_totalSupply);
}
// this low-level function should be called from another contract
function mint(address minter) external nonReentrant update returns (uint mintTokens) {
uint balance = IERC20(underlying).balanceOf(address(this));
uint mintAmount = balance.sub(totalBalance);
mintTokens = mintAmount.mul(1e18).div(exchangeRate());
if(totalSupply == 0) {
// permanently lock the first MINIMUM_LIQUIDITY tokens
mintTokens = mintTokens.sub(MINIMUM_LIQUIDITY);
_mint(address(0), MINIMUM_LIQUIDITY);
}
require(mintTokens > 0, "Impermax: MINT_AMOUNT_ZERO");
_mint(minter, mintTokens);
emit Mint(msg.sender, minter, mintAmount, mintTokens);
}
// this low-level function should be called from another contract
function redeem(address redeemer) external nonReentrant update returns (uint redeemAmount) {
uint redeemTokens = balanceOf[address(this)];
redeemAmount = redeemTokens.mul(exchangeRate()).div(1e18);
require(redeemAmount > 0, "Impermax: REDEEM_AMOUNT_ZERO");
require(redeemAmount <= totalBalance, "Impermax: INSUFFICIENT_CASH");
_burn(address(this), redeemTokens);
_safeTransfer(redeemer, redeemAmount);
emit Redeem(msg.sender, redeemer, redeemAmount, redeemTokens);
}
// force real balance to match totalBalance
function skim(address to) external nonReentrant {
_safeTransfer(to, IERC20(underlying).balanceOf(address(this)).sub(totalBalance));
}
// force totalBalance to match real balance
function sync() external nonReentrant update {}
/*** Utilities ***/
// same safe transfer function used by UniSwapV2 (with fixed underlying)
bytes4 private constant SELECTOR = bytes4(keccak256(bytes("transfer(address,uint256)")));
function _safeTransfer(address to, uint amount) internal {
(bool success, bytes memory data) = underlying.call(abi.encodeWithSelector(SELECTOR, to, amount));
require(success && (data.length == 0 || abi.decode(data, (bool))), "Impermax: TRANSFER_FAILED");
}
// prevents a contract from calling itself, directly or indirectly.
bool internal _notEntered = true;
modifier nonReentrant() {
require(_notEntered, "Impermax: REENTERED");
_notEntered = false;
_;
_notEntered = true;
}
// update totalBalance with current balance
modifier update() {
_;
_update();
}
}
// File: contracts\CStorage.sol
pragma solidity =0.5.16;
contract CStorage {
address public borrowable0;
address public borrowable1;
uint public safetyMarginSqrt = 1.58113883e18; //safetyMargin: 250%
uint public liquidationIncentive = 1.04e18; //4%
function safe112(uint n) internal pure returns (uint112) {
require(n < 2**112, "Impermax: SAFE112");
return uint112(n);
}
}
// File: contracts\interfaces\IFactory.sol
pragma solidity >=0.5.0;
interface IFactory {
event LendingPoolInitialized(address indexed uniswapV2Pair, address indexed token0, address indexed token1,
address collateral, address borrowable0, address borrowable1, uint lendingPoolId);
event NewPendingAdmin(address oldPendingAdmin, address newPendingAdmin);
event NewAdmin(address oldAdmin, address newAdmin);
event NewReservesPendingAdmin(address oldReservesPendingAdmin, address newReservesPendingAdmin);
event NewReservesAdmin(address oldReservesAdmin, address newReservesAdmin);
event NewReservesManager(address oldReservesManager, address newReservesManager);
function admin() external view returns (address);
function pendingAdmin() external view returns (address);
function reservesAdmin() external view returns (address);
function reservesPendingAdmin() external view returns (address);
function reservesManager() external view returns (address);
function getLendingPool(address uniswapV2Pair) external view returns (
bool initialized,
uint24 lendingPoolId,
address collateral,
address borrowable0,
address borrowable1
);
function allLendingPools(uint) external view returns (address uniswapV2Pair);
function allLendingPoolsLength() external view returns (uint);
function bDeployer() external view returns (address);
function cDeployer() external view returns (address);
function createCollateral(address uniswapV2Pair) external returns (address collateral);
function createBorrowable0(address uniswapV2Pair) external returns (address borrowable0);
function createBorrowable1(address uniswapV2Pair) external returns (address borrowable1);
function initializeLendingPool(address uniswapV2Pair) external;
function _setPendingAdmin(address newPendingAdmin) external;
function _acceptAdmin() external;
function _setReservesPendingAdmin(address newPendingAdmin) external;
function _acceptReservesAdmin() external;
function _setReservesManager(address newReservesManager) external;
}
// File: contracts\CSetter.sol
pragma solidity =0.5.16;
contract CSetter is PoolToken, CStorage {
uint public constant SAFETY_MARGIN_SQRT_MIN = 1.00e18; //safetyMargin: 100%
uint public constant SAFETY_MARGIN_SQRT_MAX = 1.58113884e18; //safetyMargin: 250%
uint public constant LIQUIDATION_INCENTIVE_MIN = 1.00e18; //100%
uint public constant LIQUIDATION_INCENTIVE_MAX = 1.05e18; //105%
event NewSafetyMargin(uint newSafetyMarginSqrt);
event NewLiquidationIncentive(uint newLiquidationIncentive);
// called once by the factory at the time of deployment
function _initialize (
string calldata _name,
string calldata _symbol,
address _underlying,
address _borrowable0,
address _borrowable1
) external {
require(msg.sender == factory, "Impermax: UNAUTHORIZED"); // sufficient check
_setName(_name, _symbol);
underlying = _underlying;
borrowable0 = _borrowable0;
borrowable1 = _borrowable1;
}
function _setSafetyMarginSqrt(uint newSafetyMarginSqrt) external nonReentrant {
_checkSetting(newSafetyMarginSqrt, SAFETY_MARGIN_SQRT_MIN, SAFETY_MARGIN_SQRT_MAX);
safetyMarginSqrt = newSafetyMarginSqrt;
emit NewSafetyMargin(newSafetyMarginSqrt);
}
function _setLiquidationIncentive(uint newLiquidationIncentive) external nonReentrant {
_checkSetting(newLiquidationIncentive, LIQUIDATION_INCENTIVE_MIN, LIQUIDATION_INCENTIVE_MAX);
liquidationIncentive = newLiquidationIncentive;
emit NewLiquidationIncentive(newLiquidationIncentive);
}
function _checkSetting(uint parameter, uint min, uint max) internal view {
_checkAdmin();
require(parameter >= min, "Impermax: INVALID_SETTING");
require(parameter <= max, "Impermax: INVALID_SETTING");
}
function _checkAdmin() internal view {
require(msg.sender == IFactory(factory).admin(), "Impermax: UNAUTHORIZED");
}
}
// File: contracts\interfaces\IBorrowable.sol
pragma solidity >=0.5.0;
interface IBorrowable {
/*** Impermax ERC20 ***/
event Transfer(address indexed from, address indexed to, uint value);
event Approval(address indexed owner, address indexed spender, uint value);
function name() external pure returns (string memory);
function symbol() external pure returns (string memory);
function decimals() external pure returns (uint8);
function totalSupply() external view returns (uint);
function balanceOf(address owner) external view returns (uint);
function allowance(address owner, address spender) external view returns (uint);
function approve(address spender, uint value) external returns (bool);
function transfer(address to, uint value) external returns (bool);
function transferFrom(address from, address to, uint value) external returns (bool);
function DOMAIN_SEPARATOR() external view returns (bytes32);
function PERMIT_TYPEHASH() external pure returns (bytes32);
function nonces(address owner) external view returns (uint);
function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
/*** Pool Token ***/
event Mint(address indexed sender, address indexed minter, uint mintAmount, uint mintTokens);
event Redeem(address indexed sender, address indexed redeemer, uint redeemAmount, uint redeemTokens);
event Sync(uint totalBalance);
function underlying() external view returns (address);
function factory() external view returns (address);
function totalBalance() external view returns (uint);
function MINIMUM_LIQUIDITY() external pure returns (uint);
function exchangeRate() external returns (uint);
function mint(address minter) external returns (uint mintTokens);
function redeem(address redeemer) external returns (uint redeemAmount);
function skim(address to) external;
function sync() external;
function _setFactory() external;
/*** Borrowable ***/
event BorrowApproval(address indexed owner, address indexed spender, uint value);
event Borrow(address indexed sender, address indexed borrower, address indexed receiver, uint borrowAmount, uint repayAmount, uint accountBorrowsPrior, uint accountBorrows, uint totalBorrows);
event Liquidate(address indexed sender, address indexed borrower, address indexed liquidator, uint seizeTokens, uint repayAmount, uint accountBorrowsPrior, uint accountBorrows, uint totalBorrows);
function BORROW_FEE() external pure returns (uint);
function collateral() external view returns (address);
function reserveFactor() external view returns (uint);
function exchangeRateLast() external view returns (uint);
function borrowIndex() external view returns (uint);
function totalBorrows() external view returns (uint);
function borrowAllowance(address owner, address spender) external view returns (uint);
function borrowBalance(address borrower) external view returns (uint);
function borrowTracker() external view returns (address);
function BORROW_PERMIT_TYPEHASH() external pure returns (bytes32);
function borrowApprove(address spender, uint256 value) external returns (bool);
function borrowPermit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
function borrow(address borrower, address receiver, uint borrowAmount, bytes calldata data) external;
function liquidate(address borrower, address liquidator) external returns (uint seizeTokens);
function trackBorrow(address borrower) external;
/*** Borrowable Interest Rate Model ***/
event AccrueInterest(uint interestAccumulated, uint borrowIndex, uint totalBorrows);
event CalculateKink(uint kinkRate);
event CalculateBorrowRate(uint borrowRate);
function KINK_BORROW_RATE_MAX() external pure returns (uint);
function KINK_BORROW_RATE_MIN() external pure returns (uint);
function KINK_MULTIPLIER() external pure returns (uint);
function borrowRate() external view returns (uint);
function kinkBorrowRate() external view returns (uint);
function kinkUtilizationRate() external view returns (uint);
function adjustSpeed() external view returns (uint);
function rateUpdateTimestamp() external view returns (uint32);
function accrualTimestamp() external view returns (uint32);
function accrueInterest() external;
/*** Borrowable Setter ***/
event NewReserveFactor(uint newReserveFactor);
event NewKinkUtilizationRate(uint newKinkUtilizationRate);
event NewAdjustSpeed(uint newAdjustSpeed);
event NewBorrowTracker(address newBorrowTracker);
function RESERVE_FACTOR_MAX() external pure returns (uint);
function KINK_UR_MIN() external pure returns (uint);
function KINK_UR_MAX() external pure returns (uint);
function ADJUST_SPEED_MIN() external pure returns (uint);
function ADJUST_SPEED_MAX() external pure returns (uint);
function _initialize (
string calldata _name,
string calldata _symbol,
address _underlying,
address _collateral
) external;
function _setReserveFactor(uint newReserveFactor) external;
function _setKinkUtilizationRate(uint newKinkUtilizationRate) external;
function _setAdjustSpeed(uint newAdjustSpeed) external;
function _setBorrowTracker(address newBorrowTracker) external;
}
// File: contracts\interfaces\ICollateral.sol
pragma solidity >=0.5.0;
interface ICollateral {
/*** Impermax ERC20 ***/
event Transfer(address indexed from, address indexed to, uint value);
event Approval(address indexed owner, address indexed spender, uint value);
function name() external pure returns (string memory);
function symbol() external pure returns (string memory);
function decimals() external pure returns (uint8);
function totalSupply() external view returns (uint);
function balanceOf(address owner) external view returns (uint);
function allowance(address owner, address spender) external view returns (uint);
function approve(address spender, uint value) external returns (bool);
function transfer(address to, uint value) external returns (bool);
function transferFrom(address from, address to, uint value) external returns (bool);
function DOMAIN_SEPARATOR() external view returns (bytes32);
function PERMIT_TYPEHASH() external pure returns (bytes32);
function nonces(address owner) external view returns (uint);
function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
/*** Pool Token ***/
event Mint(address indexed sender, address indexed minter, uint mintAmount, uint mintTokens);
event Redeem(address indexed sender, address indexed redeemer, uint redeemAmount, uint redeemTokens);
event Sync(uint totalBalance);
function underlying() external view returns (address);
function factory() external view returns (address);
function totalBalance() external view returns (uint);
function MINIMUM_LIQUIDITY() external pure returns (uint);
function exchangeRate() external returns (uint);
function mint(address minter) external returns (uint mintTokens);
function redeem(address redeemer) external returns (uint redeemAmount);
function skim(address to) external;
function sync() external;
function _setFactory() external;
/*** Collateral ***/
function borrowable0() external view returns (address);
function borrowable1() external view returns (address);
function safetyMarginSqrt() external view returns (uint);
function liquidationIncentive() external view returns (uint);
function getPrices() external returns (uint price0, uint price1);
function tokensUnlocked(address from, uint value) external returns (bool);
function accountLiquidityAmounts(address account, uint amount0, uint amount1) external returns (uint liquidity, uint shortfall);
function accountLiquidity(address account) external returns (uint liquidity, uint shortfall);
function canBorrow(address account, address borrowable, uint accountBorrows) external returns (bool);
function seize(address liquidator, address borrower, uint repayAmount) external returns (uint seizeTokens);
function flashRedeem(address redeemer, uint redeemAmount, bytes calldata data) external;
/*** Collateral Setter ***/
event NewSafetyMargin(uint newSafetyMarginSqrt);
event NewLiquidationIncentive(uint newLiquidationIncentive);
function SAFETY_MARGIN_SQRT_MIN() external pure returns (uint);
function SAFETY_MARGIN_SQRT_MAX() external pure returns (uint);
function LIQUIDATION_INCENTIVE_MIN() external pure returns (uint);
function LIQUIDATION_INCENTIVE_MAX() external pure returns (uint);
function _initialize (
string calldata _name,
string calldata _symbol,
address _underlying,
address _borrowable0,
address _borrowable1
) external;
function _setSafetyMarginSqrt(uint newSafetyMarginSqrt) external;
function _setLiquidationIncentive(uint newLiquidationIncentive) external;
}
// File: contracts\interfaces\IImpermaxCallee.sol
pragma solidity >=0.5.0;
interface IImpermaxCallee {
function impermaxBorrow(address sender, address borrower, uint borrowAmount, bytes calldata data) external;
function impermaxRedeem(address sender, uint redeemAmount, bytes calldata data) external;
}
// File: contracts\interfaces\IUniswapV2Pair.sol
pragma solidity >=0.5.0;
interface IUniswapV2Pair {
event Approval(address indexed owner, address indexed spender, uint value);
event Transfer(address indexed from, address indexed to, uint value);
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view returns (uint8);
function totalSupply() external view returns (uint);
function balanceOf(address owner) external view returns (uint);
function allowance(address owner, address spender) external view returns (uint);
function approve(address spender, uint value) external returns (bool);
function transfer(address to, uint value) external returns (bool);
function transferFrom(address from, address to, uint value) external returns (bool);
function token0() external view returns (address);
function token1() external view returns (address);
function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
function observationLength() external view returns (uint);
function observations(uint) external view returns (
uint timestamp,
uint reserve0Cumulative,
uint reserve1Cumulative
);
function currentCumulativePrices() external view returns (
uint reserve0Cumulative,
uint reserve1Cumulative,
uint timestamp
);
}
// File: contracts\libraries\UQ112x112.sol
pragma solidity =0.5.16;
// a library for handling binary fixed point numbers (https://en.wikipedia.org/wiki/Q_(number_format))
// src: https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/libraries/UQ112x112.sol
// range: [0, 2**112 - 1]
// resolution: 1 / 2**112
library UQ112x112 {
uint224 constant Q112 = 2**112;
// encode a uint112 as a UQ112x112
function encode(uint112 y) internal pure returns (uint224 z) {
z = uint224(y) * Q112; // never overflows
}
// divide a UQ112x112 by a uint112, returning a UQ112x112
function uqdiv(uint224 x, uint112 y) internal pure returns (uint224 z) {
z = x / uint224(y);
}
}
// File: contracts\libraries\Math.sol
pragma solidity =0.5.16;
// a library for performing various math operations
// forked from: https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/libraries/Math.sol
library Math {
function min(uint x, uint y) internal pure returns (uint z) {
z = x < y ? x : y;
}
// babylonian method (https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)
function sqrt(uint y) internal pure returns (uint z) {
if (y > 3) {
z = y;
uint x = y / 2 + 1;
while (x < z) {
z = x;
x = (y / x + x) / 2;
}
} else if (y != 0) {
z = 1;
}
}
}
// File: contracts\Collateral.sol
pragma solidity =0.5.16;
contract Collateral is ICollateral, PoolToken, CStorage, CSetter {
using UQ112x112 for uint224;
constructor() public {}
/*** Collateralization Model ***/
function getTwapPrice112x112() public returns(uint224 twapPrice112x112) {
uint length = IUniswapV2Pair(underlying).observationLength();
(uint lastTimestamp, uint lastReserve0Cumulative, uint lastReserve1Cumulative) = IUniswapV2Pair(underlying).observations(length-2);
(uint reserve0Cumulative, uint reserve1Cumulative, uint timestamp) = IUniswapV2Pair(underlying).currentCumulativePrices();
uint timeElapsed = timestamp - lastTimestamp;
uint112 twapReserve0 = safe112((reserve0Cumulative - lastReserve0Cumulative) / timeElapsed);
uint112 twapReserve1 = safe112((reserve1Cumulative - lastReserve1Cumulative) / timeElapsed);
twapPrice112x112 = UQ112x112.encode(twapReserve1).uqdiv(twapReserve0);
}
function getPrices() public returns (uint price0, uint price1) {
uint224 twapPrice112x112 = getTwapPrice112x112();
(uint112 reserve0, uint112 reserve1,) = IUniswapV2Pair(underlying).getReserves();
uint256 collateralTotalSupply = IUniswapV2Pair(underlying).totalSupply();
uint224 currentPrice112x112 = UQ112x112.encode(reserve1).uqdiv(reserve0);
uint256 adjustmentSquared = uint256(twapPrice112x112).mul(2**32).div(currentPrice112x112);
uint256 adjustment = Math.sqrt(adjustmentSquared.mul(2**32));
uint256 currentBorrowable0Price = uint256(collateralTotalSupply).mul(1e18).div(reserve0*2);
uint256 currentBorrowable1Price = uint256(collateralTotalSupply).mul(1e18).div(reserve1*2);
price0 = currentBorrowable0Price.mul(adjustment).div(2**32);
price1 = currentBorrowable1Price.mul(2**32).div(adjustment);
/*
* Price calculation errors may happen in some edge pairs where
* reserve0 / reserve1 is close to 2**112 or 1/2**112
* We're going to prevent users from using pairs at risk from the UI
*/
require(price0 > 100, "Impermax: PRICE_CALCULATION_ERROR");
require(price1 > 100, "Impermax: PRICE_CALCULATION_ERROR");
}
// returns liquidity in collateral's underlying
function _calculateLiquidity(uint amountCollateral, uint amount0, uint amount1) internal returns (uint liquidity, uint shortfall) {
uint _safetyMarginSqrt = safetyMarginSqrt;
(uint price0, uint price1) = getPrices();
uint a = amount0.mul(price0).div(1e18);
uint b = amount1.mul(price1).div(1e18);
if(a < b) (a, b) = (b, a);
a = a.mul(_safetyMarginSqrt).div(1e18);
b = b.mul(1e18).div(_safetyMarginSqrt);
uint collateralNeeded = a.add(b).mul(liquidationIncentive).div(1e18);
if(amountCollateral >= collateralNeeded){
return (amountCollateral - collateralNeeded, 0);
} else {
return (0, collateralNeeded - amountCollateral);
}
}
/*** ERC20 ***/
function _transfer(address from, address to, uint value) internal {
require(tokensUnlocked(from, value), "Impermax: INSUFFICIENT_LIQUIDITY");
super._transfer(from, to, value);
}
function tokensUnlocked(address from, uint value) public returns (bool) {
uint _balance = balanceOf[from];
if (value > _balance) return false;
uint finalBalance = _balance - value;
uint amountCollateral = finalBalance.mul(exchangeRate()).div(1e18);
uint amount0 = IBorrowable(borrowable0).borrowBalance(from);
uint amount1 = IBorrowable(borrowable1).borrowBalance(from);
(, uint shortfall) = _calculateLiquidity(amountCollateral, amount0, amount1);
return shortfall == 0;
}
/*** Collateral ***/
function accountLiquidityAmounts(address borrower, uint amount0, uint amount1) public returns (uint liquidity, uint shortfall) {
if (amount0 == uint(-1)) amount0 = IBorrowable(borrowable0).borrowBalance(borrower);
if (amount1 == uint(-1)) amount1 = IBorrowable(borrowable1).borrowBalance(borrower);
uint amountCollateral = balanceOf[borrower].mul(exchangeRate()).div(1e18);
return _calculateLiquidity(amountCollateral, amount0, amount1);
}
function accountLiquidity(address borrower) public returns (uint liquidity, uint shortfall) {
return accountLiquidityAmounts(borrower, uint(-1), uint(-1));
}
function canBorrow(address borrower, address borrowable, uint accountBorrows) public returns (bool) {
address _borrowable0 = borrowable0;
address _borrowable1 = borrowable1;
require(borrowable == _borrowable0 || borrowable == _borrowable1, "Impermax: INVALID_BORROWABLE" );
uint amount0 = borrowable == _borrowable0 ? accountBorrows : uint(-1);
uint amount1 = borrowable == _borrowable1 ? accountBorrows : uint(-1);
(, uint shortfall) = accountLiquidityAmounts(borrower, amount0, amount1);
return shortfall == 0;
}
// this function must be called from borrowable0 or borrowable1
function seize(address liquidator, address borrower, uint repayAmount) external returns (uint seizeTokens) {
require(msg.sender == borrowable0 || msg.sender == borrowable1, "Impermax: UNAUTHORIZED");
(, uint shortfall) = accountLiquidity(borrower);
require(shortfall > 0, "Impermax: INSUFFICIENT_SHORTFALL");
uint price;
if (msg.sender == borrowable0) (price, ) = getPrices();
else (, price) = getPrices();
seizeTokens = repayAmount.mul(liquidationIncentive).div(1e18).mul(price).div( exchangeRate() );
balanceOf[borrower] = balanceOf[borrower].sub(seizeTokens, "Impermax: LIQUIDATING_TOO_MUCH");
balanceOf[liquidator] = balanceOf[liquidator].add(seizeTokens);
emit Transfer(borrower, liquidator, seizeTokens);
}
// this low-level function should be called from another contract
function flashRedeem(address redeemer, uint redeemAmount, bytes calldata data) external nonReentrant update {
require(redeemAmount <= totalBalance, "Impermax: INSUFFICIENT_CASH");
// optimistically transfer funds
_safeTransfer(redeemer, redeemAmount);
if (data.length > 0) IImpermaxCallee(redeemer).impermaxRedeem(msg.sender, redeemAmount, data);
uint redeemTokens = balanceOf[address(this)];
uint declaredRedeemTokens = redeemAmount.mul(1e18).div( exchangeRate() ).add(1); // rounded up
require(redeemTokens >= declaredRedeemTokens, "Impermax: INSUFFICIENT_REDEEM_TOKENS");
_burn(address(this), redeemTokens);
emit Redeem(msg.sender, redeemer, redeemAmount, redeemTokens);
}
}
// File: contracts\interfaces\ICDeployer.sol
pragma solidity >=0.5.0;
interface ICDeployer {
function deployCollateral(address uniswapV2Pair) external returns (address collateral);
}
// File: contracts\CDeployer.sol
pragma solidity =0.5.16;
/*
* This contract is used by the Factory to deploy Collateral(s)
* The bytecode would be too long to fit in the Factory
*/
contract CDeployer is ICDeployer {
constructor () public {}
function deployCollateral(address uniswapV2Pair) external returns (address collateral) {
bytes memory bytecode = type(Collateral).creationCode;
bytes32 salt = keccak256(abi.encodePacked(msg.sender, uniswapV2Pair));
assembly {
collateral := create2(0, add(bytecode, 32), mload(bytecode), salt)
}
}
}