// File: contracts/ComptrollerInterface.sol pragma solidity ^0.5.16; contract ComptrollerInterface { /// @notice Indicator that this is a Comptroller contract (for inspection) bool public constant isComptroller = true; /*** Assets You Are In ***/ function enterMarkets(address[] calldata slTokens) external returns (uint[] memory); function exitMarket(address slToken) external returns (uint); /*** Policy Hooks ***/ function mintAllowed(address slToken, address minter, uint mintAmount) external returns (uint); function mintVerify(address slToken, address minter, uint mintAmount, uint mintTokens) external; function redeemAllowed(address slToken, address redeemer, uint redeemTokens) external returns (uint); function redeemVerify(address slToken, address redeemer, uint redeemAmount, uint redeemTokens) external; function borrowAllowed(address slToken, address borrower, uint borrowAmount) external returns (uint); function borrowVerify(address slToken, address borrower, uint borrowAmount) external; function repayBorrowAllowed( address slToken, address payer, address borrower, uint repayAmount) external returns (uint); function repayBorrowVerify( address slToken, address payer, address borrower, uint repayAmount, uint borrowerIndex) external; function liquidateBorrowAllowed( address slTokenBorrowed, address slTokenCollateral, address liquidator, address borrower, uint repayAmount) external returns (uint); function liquidateBorrowVerify( address slTokenBorrowed, address slTokenCollateral, address liquidator, address borrower, uint repayAmount, uint seizeTokens) external; function seizeAllowed( address slTokenCollateral, address slTokenBorrowed, address liquidator, address borrower, uint seizeTokens) external returns (uint); function seizeVerify( address slTokenCollateral, address slTokenBorrowed, address liquidator, address borrower, uint seizeTokens) external; function transferAllowed(address slToken, address src, address dst, uint transferTokens) external returns (uint); function transferVerify(address slToken, address src, address dst, uint transferTokens) external; /*** Liquidity/Liquidation Calculations ***/ function liquidateCalculateSeizeTokens( address slTokenBorrowed, address slTokenCollateral, uint repayAmount) external view returns (uint, uint); } // File: contracts/InterestRateModel.sol pragma solidity ^0.5.16; /** * @title Compound's InterestRateModel Interface * @author Compound */ contract InterestRateModel { /// @notice Indicator that this is an InterestRateModel contract (for inspection) bool public constant isInterestRateModel = true; /** * @notice Calculates the current borrow interest rate per block * @param cash The total amount of cash the market has * @param borrows The total amount of borrows the market has outstanding * @param reserves The total amount of reserves the market has * @return The borrow rate per block (as a percentage, and scaled by 1e18) */ function getBorrowRate(uint cash, uint borrows, uint reserves) external view returns (uint); /** * @notice Calculates the current supply interest rate per block * @param cash The total amount of cash the market has * @param borrows The total amount of borrows the market has outstanding * @param reserves The total amount of reserves the market has * @param reserveFactorMantissa The current reserve factor the market has * @return The supply rate per block (as a percentage, and scaled by 1e18) */ function getSupplyRate(uint cash, uint borrows, uint reserves, uint reserveFactorMantissa) external view returns (uint); } // File: contracts/SLTokenInterfaces.sol pragma solidity ^0.5.16; contract SLTokenStorage { /** * @dev Guard variable for re-entrancy checks */ bool internal _notEntered; /** * @notice EIP-20 token name for this token */ string public name; /** * @notice EIP-20 token symbol for this token */ string public symbol; /** * @notice EIP-20 token decimals for this token */ uint8 public decimals; /** * @notice Maximum borrow rate that can ever be applied (.0005% / block) */ uint internal constant borrowRateMaxMantissa = 0.0005e16; /** * @notice Maximum fraction of interest that can be set aside for reserves */ uint internal constant reserveFactorMaxMantissa = 1e18; /** * @notice Administrator for this contract */ address payable public admin; /** * @notice Pending administrator for this contract */ address payable public pendingAdmin; /** * @notice Contract which oversees inter-slToken operations */ ComptrollerInterface public comptroller; /** * @notice Model which tells what the current interest rate should be */ InterestRateModel public interestRateModel; /** * @notice Initial exchange rate used when minting the first SLTokens (used when totalSupply = 0) */ uint internal initialExchangeRateMantissa; /** * @notice Fraction of interest currently set aside for reserves */ uint public reserveFactorMantissa; /** * @notice Block number that interest was last accrued at */ uint public accrualBlockNumber; /** * @notice Accumulator of the total earned interest rate since the opening of the market */ uint public borrowIndex; /** * @notice Total amount of outstanding borrows of the underlying in this market */ uint public totalBorrows; /** * @notice Total amount of reserves of the underlying held in this market */ uint public totalReserves; /** * @notice Total number of tokens in circulation */ uint public totalSupply; /** * @notice Official record of token balances for each account */ mapping (address => uint) internal accountTokens; /** * @notice Approved token transfer amounts on behalf of others */ mapping (address => mapping (address => uint)) internal transferAllowances; /** * @notice Container for borrow balance information * @member principal Total balance (with accrued interest), after applying the most recent balance-changing action * @member interestIndex Global borrowIndex as of the most recent balance-changing action */ struct BorrowSnapshot { uint principal; uint interestIndex; } /** * @notice Mapping of account addresses to outstanding borrow balances */ mapping(address => BorrowSnapshot) internal accountBorrows; } contract SLTokenInterface is SLTokenStorage { /** * @notice Indicator that this is a SLToken contract (for inspection) */ bool public constant isSLToken = true; /*** Market Events ***/ /** * @notice Event emitted when interest is accrued */ event AccrueInterest(uint cashPrior, uint interestAccumulated, uint borrowIndex, uint totalBorrows); /** * @notice Event emitted when tokens are minted */ event Mint(address minter, uint mintAmount, uint mintTokens); /** * @notice Event emitted when tokens are redeemed */ event Redeem(address redeemer, uint redeemAmount, uint redeemTokens); /** * @notice Event emitted when underlying is borrowed */ event Borrow(address borrower, uint borrowAmount, uint accountBorrows, uint totalBorrows); /** * @notice Event emitted when a borrow is repaid */ event RepayBorrow(address payer, address borrower, uint repayAmount, uint accountBorrows, uint totalBorrows); /** * @notice Event emitted when a borrow is liquidated */ event LiquidateBorrow(address liquidator, address borrower, uint repayAmount, address slTokenCollateral, uint seizeTokens); /*** Admin Events ***/ /** * @notice Event emitted when pendingAdmin is changed */ event NewPendingAdmin(address oldPendingAdmin, address newPendingAdmin); /** * @notice Event emitted when pendingAdmin is accepted, which means admin is updated */ event NewAdmin(address oldAdmin, address newAdmin); /** * @notice Event emitted when comptroller is changed */ event NewComptroller(ComptrollerInterface oldComptroller, ComptrollerInterface newComptroller); /** * @notice Event emitted when interestRateModel is changed */ event NewMarketInterestRateModel(InterestRateModel oldInterestRateModel, InterestRateModel newInterestRateModel); /** * @notice Event emitted when the reserve factor is changed */ event NewReserveFactor(uint oldReserveFactorMantissa, uint newReserveFactorMantissa); /** * @notice Event emitted when the reserves are added */ event ReservesAdded(address benefactor, uint addAmount, uint newTotalReserves); /** * @notice Event emitted when the reserves are reduced */ event ReservesReduced(address admin, uint reduceAmount, uint newTotalReserves); /** * @notice EIP20 Transfer event */ event Transfer(address indexed from, address indexed to, uint amount); /** * @notice EIP20 Approval event */ event Approval(address indexed owner, address indexed spender, uint amount); /** * @notice Failure event */ event Failure(uint error, uint info, uint detail); /*** User Interface ***/ function transfer(address dst, uint amount) external returns (bool); function transferFrom(address src, address dst, uint amount) external returns (bool); function approve(address spender, uint amount) external returns (bool); function allowance(address owner, address spender) external view returns (uint); function balanceOf(address owner) external view returns (uint); function balanceOfUnderlying(address owner) external returns (uint); function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint); function borrowRatePerBlock() external view returns (uint); function supplyRatePerBlock() external view returns (uint); function totalBorrowsCurrent() external returns (uint); function borrowBalanceCurrent(address account) external returns (uint); function borrowBalanceStored(address account) public view returns (uint); function exchangeRateCurrent() public returns (uint); function exchangeRateStored() public view returns (uint); function getCash() external view returns (uint); function accrueInterest() public returns (uint); function seize(address liquidator, address borrower, uint seizeTokens) external returns (uint); /*** Admin Functions ***/ function _setPendingAdmin(address payable newPendingAdmin) external returns (uint); function _acceptAdmin() external returns (uint); function _setComptroller(ComptrollerInterface newComptroller) public returns (uint); function _setReserveFactor(uint newReserveFactorMantissa) external returns (uint); function _reduceReserves(uint reduceAmount) external returns (uint); function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint); } contract SLErc20Storage { /** * @notice Underlying asset for this SLToken */ address public underlying; } contract SLErc20Interface is SLErc20Storage { /*** User Interface ***/ function mint(uint mintAmount) external returns (uint); function redeem(uint redeemTokens) external returns (uint); function redeemUnderlying(uint redeemAmount) external returns (uint); function borrow(uint borrowAmount) external returns (uint); function repayBorrow(uint repayAmount) external returns (uint); function repayBorrowBehalf(address borrower, uint repayAmount) external returns (uint); function liquidateBorrow(address borrower, uint repayAmount, SLTokenInterface slTokenCollateral) external returns (uint); /*** Admin Functions ***/ function _addReserves(uint addAmount) external returns (uint); } contract SLDelegationStorage { /** * @notice Implementation address for this contract */ address public implementation; } contract SLDelegatorInterface is SLDelegationStorage { /** * @notice Emitted when implementation is changed */ event NewImplementation(address oldImplementation, address newImplementation); /** * @notice Called by the admin to update the implementation of the delegator * @param implementation_ The address of the new implementation for delegation * @param allowResign Flag to indicate whether to call _resignImplementation on the old implementation * @param becomeImplementationData The encoded bytes data to be passed to _becomeImplementation */ function _setImplementation(address implementation_, bool allowResign, bytes memory becomeImplementationData) public; } contract SLDelegateInterface is SLDelegationStorage { /** * @notice Called by the delegator on a delegate to initialize it for duty * @dev Should revert if any issues arise which make it unfit for delegation * @param data The encoded bytes data for any initialization */ function _becomeImplementation(bytes memory data) public; /** * @notice Called by the delegator on a delegate to forfeit its responsibility */ function _resignImplementation() public; } // File: contracts/ErrorReporter.sol pragma solidity ^0.5.16; contract ComptrollerErrorReporter { enum Error { NO_ERROR, UNAUTHORIZED, COMPTROLLER_MISMATCH, INSUFFICIENT_SHORTFALL, INSUFFICIENT_LIQUIDITY, INVALID_CLOSE_FACTOR, INVALID_COLLATERAL_FACTOR, INVALID_LIQUIDATION_INCENTIVE, MARKET_NOT_ENTERED, // no longer possible MARKET_NOT_LISTED, MARKET_ALREADY_LISTED, MATH_ERROR, NONZERO_BORROW_BALANCE, PRICE_ERROR, REJECTION, SNAPSHOT_ERROR, TOO_MANY_ASSETS, TOO_MUCH_REPAY } enum FailureInfo { ACCEPT_ADMIN_PENDING_ADMIN_CHECK, ACCEPT_PENDING_IMPLEMENTATION_ADDRESS_CHECK, EXIT_MARKET_BALANCE_OWED, EXIT_MARKET_REJECTION, SET_CLOSE_FACTOR_OWNER_CHECK, SET_CLOSE_FACTOR_VALIDATION, SET_COLLATERAL_FACTOR_OWNER_CHECK, SET_COLLATERAL_FACTOR_NO_EXISTS, SET_COLLATERAL_FACTOR_VALIDATION, SET_COLLATERAL_FACTOR_WITHOUT_PRICE, SET_IMPLEMENTATION_OWNER_CHECK, SET_LIQUIDATION_INCENTIVE_OWNER_CHECK, SET_LIQUIDATION_INCENTIVE_VALIDATION, SET_MAX_ASSETS_OWNER_CHECK, SET_PENDING_ADMIN_OWNER_CHECK, SET_PENDING_IMPLEMENTATION_OWNER_CHECK, SET_PRICE_ORACLE_OWNER_CHECK, SUPPORT_MARKET_EXISTS, SUPPORT_MARKET_OWNER_CHECK, SET_PAUSE_GUARDIAN_OWNER_CHECK } /** * @dev `error` corresponds to enum Error; `info` corresponds to enum FailureInfo, and `detail` is an arbitrary * contract-specific code that enables us to report opaque error codes from upgradeable contracts. **/ event Failure(uint error, uint info, uint detail); /** * @dev use this when reporting a known error from the money market or a non-upgradeable collaborator */ function fail(Error err, FailureInfo info) internal returns (uint) { emit Failure(uint(err), uint(info), 0); return uint(err); } /** * @dev use this when reporting an opaque error from an upgradeable collaborator contract */ function failOpaque(Error err, FailureInfo info, uint opaqueError) internal returns (uint) { emit Failure(uint(err), uint(info), opaqueError); return uint(err); } } contract TokenErrorReporter { enum Error { NO_ERROR, UNAUTHORIZED, BAD_INPUT, COMPTROLLER_REJECTION, COMPTROLLER_CALCULATION_ERROR, INTEREST_RATE_MODEL_ERROR, INVALID_ACCOUNT_PAIR, INVALID_CLOSE_AMOUNT_REQUESTED, INVALID_COLLATERAL_FACTOR, MATH_ERROR, MARKET_NOT_FRESH, MARKET_NOT_LISTED, TOKEN_INSUFFICIENT_ALLOWANCE, TOKEN_INSUFFICIENT_BALANCE, TOKEN_INSUFFICIENT_CASH, TOKEN_TRANSFER_IN_FAILED, TOKEN_TRANSFER_OUT_FAILED } /* * Note: FailureInfo (but not Error) is kept in alphabetical order * This is because FailureInfo grows significantly faster, and * the order of Error has some meaning, while the order of FailureInfo * is entirely arbitrary. */ enum FailureInfo { ACCEPT_ADMIN_PENDING_ADMIN_CHECK, ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, ACCRUE_INTEREST_BORROW_RATE_CALCULATION_FAILED, ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, BORROW_ACCRUE_INTEREST_FAILED, BORROW_CASH_NOT_AVAILABLE, BORROW_FRESHNESS_CHECK, BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, BORROW_MARKET_NOT_LISTED, BORROW_COMPTROLLER_REJECTION, LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED, LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED, LIQUIDATE_COLLATERAL_FRESHNESS_CHECK, LIQUIDATE_COMPTROLLER_REJECTION, LIQUIDATE_COMPTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED, LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX, LIQUIDATE_CLOSE_AMOUNT_IS_ZERO, LIQUIDATE_FRESHNESS_CHECK, LIQUIDATE_LIQUIDATOR_IS_BORROWER, LIQUIDATE_REPAY_BORROW_FRESH_FAILED, LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, LIQUIDATE_SEIZE_COMPTROLLER_REJECTION, LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER, LIQUIDATE_SEIZE_TOO_MUCH, MINT_ACCRUE_INTEREST_FAILED, MINT_COMPTROLLER_REJECTION, MINT_EXCHANGE_CALCULATION_FAILED, MINT_EXCHANGE_RATE_READ_FAILED, MINT_FRESHNESS_CHECK, MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, MINT_TRANSFER_IN_FAILED, MINT_TRANSFER_IN_NOT_POSSIBLE, REDEEM_ACCRUE_INTEREST_FAILED, REDEEM_COMPTROLLER_REJECTION, REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, REDEEM_EXCHANGE_RATE_READ_FAILED, REDEEM_FRESHNESS_CHECK, REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, REDEEM_TRANSFER_OUT_NOT_POSSIBLE, REDUCE_RESERVES_ACCRUE_INTEREST_FAILED, REDUCE_RESERVES_ADMIN_CHECK, REDUCE_RESERVES_CASH_NOT_AVAILABLE, REDUCE_RESERVES_FRESH_CHECK, REDUCE_RESERVES_VALIDATION, REPAY_BEHALF_ACCRUE_INTEREST_FAILED, REPAY_BORROW_ACCRUE_INTEREST_FAILED, REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, REPAY_BORROW_COMPTROLLER_REJECTION, REPAY_BORROW_FRESHNESS_CHECK, REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, REPAY_BORROW_TRANSFER_IN_NOT_POSSIBLE, SET_COLLATERAL_FACTOR_OWNER_CHECK, SET_COLLATERAL_FACTOR_VALIDATION, SET_COMPTROLLER_OWNER_CHECK, SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED, SET_INTEREST_RATE_MODEL_FRESH_CHECK, SET_INTEREST_RATE_MODEL_OWNER_CHECK, SET_MAX_ASSETS_OWNER_CHECK, SET_ORACLE_MARKET_NOT_LISTED, SET_PENDING_ADMIN_OWNER_CHECK, SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED, SET_RESERVE_FACTOR_ADMIN_CHECK, SET_RESERVE_FACTOR_FRESH_CHECK, SET_RESERVE_FACTOR_BOUNDS_CHECK, TRANSFER_COMPTROLLER_REJECTION, TRANSFER_NOT_ALLOWED, TRANSFER_NOT_ENOUGH, TRANSFER_TOO_MUCH, ADD_RESERVES_ACCRUE_INTEREST_FAILED, ADD_RESERVES_FRESH_CHECK, ADD_RESERVES_TRANSFER_IN_NOT_POSSIBLE } /** * @dev `error` corresponds to enum Error; `info` corresponds to enum FailureInfo, and `detail` is an arbitrary * contract-specific code that enables us to report opaque error codes from upgradeable contracts. **/ event Failure(uint error, uint info, uint detail); /** * @dev use this when reporting a known error from the money market or a non-upgradeable collaborator */ function fail(Error err, FailureInfo info) internal returns (uint) { emit Failure(uint(err), uint(info), 0); return uint(err); } /** * @dev use this when reporting an opaque error from an upgradeable collaborator contract */ function failOpaque(Error err, FailureInfo info, uint opaqueError) internal returns (uint) { emit Failure(uint(err), uint(info), opaqueError); return uint(err); } } // File: contracts/CarefulMath.sol pragma solidity ^0.5.16; /** * @title Careful Math * @author Compound * @notice Derived from OpenZeppelin's SafeMath library * https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/math/SafeMath.sol */ contract CarefulMath { /** * @dev Possible error codes that we can return */ enum MathError { NO_ERROR, DIVISION_BY_ZERO, INTEGER_OVERFLOW, INTEGER_UNDERFLOW } /** * @dev Multiplies two numbers, returns an error on overflow. */ function mulUInt(uint a, uint b) internal pure returns (MathError, uint) { if (a == 0) { return (MathError.NO_ERROR, 0); } uint c = a * b; if (c / a != b) { return (MathError.INTEGER_OVERFLOW, 0); } else { return (MathError.NO_ERROR, c); } } /** * @dev Integer division of two numbers, truncating the quotient. */ function divUInt(uint a, uint b) internal pure returns (MathError, uint) { if (b == 0) { return (MathError.DIVISION_BY_ZERO, 0); } return (MathError.NO_ERROR, a / b); } /** * @dev Subtracts two numbers, returns an error on overflow (i.e. if subtrahend is greater than minuend). */ function subUInt(uint a, uint b) internal pure returns (MathError, uint) { if (b <= a) { return (MathError.NO_ERROR, a - b); } else { return (MathError.INTEGER_UNDERFLOW, 0); } } /** * @dev Adds two numbers, returns an error on overflow. */ function addUInt(uint a, uint b) internal pure returns (MathError, uint) { uint c = a + b; if (c >= a) { return (MathError.NO_ERROR, c); } else { return (MathError.INTEGER_OVERFLOW, 0); } } /** * @dev add a and b and then subtract c */ function addThenSubUInt(uint a, uint b, uint c) internal pure returns (MathError, uint) { (MathError err0, uint sum) = addUInt(a, b); if (err0 != MathError.NO_ERROR) { return (err0, 0); } return subUInt(sum, c); } } // File: contracts/Exponential.sol pragma solidity ^0.5.16; /** * @title Exponential module for storing fixed-precision decimals * @author Compound * @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places. * Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is: * `Exp({mantissa: 5100000000000000000})`. */ contract Exponential is CarefulMath { uint constant expScale = 1e18; uint constant doubleScale = 1e36; uint constant halfExpScale = expScale/2; uint constant mantissaOne = expScale; struct Exp { uint mantissa; } struct Double { uint mantissa; } /** * @dev Creates an exponential from numerator and denominator values. * Note: Returns an error if (`num` * 10e18) > MAX_INT, * or if `denom` is zero. */ function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) { (MathError err0, uint scaledNumerator) = mulUInt(num, expScale); if (err0 != MathError.NO_ERROR) { return (err0, Exp({mantissa: 0})); } (MathError err1, uint rational) = divUInt(scaledNumerator, denom); if (err1 != MathError.NO_ERROR) { return (err1, Exp({mantissa: 0})); } return (MathError.NO_ERROR, Exp({mantissa: rational})); } /** * @dev Adds two exponentials, returning a new exponential. */ function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) { (MathError error, uint result) = addUInt(a.mantissa, b.mantissa); return (error, Exp({mantissa: result})); } /** * @dev Subtracts two exponentials, returning a new exponential. */ function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) { (MathError error, uint result) = subUInt(a.mantissa, b.mantissa); return (error, Exp({mantissa: result})); } /** * @dev Multiply an Exp by a scalar, returning a new Exp. */ function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) { (MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar); if (err0 != MathError.NO_ERROR) { return (err0, Exp({mantissa: 0})); } return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa})); } /** * @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer. */ function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) { (MathError err, Exp memory product) = mulScalar(a, scalar); if (err != MathError.NO_ERROR) { return (err, 0); } return (MathError.NO_ERROR, truncate(product)); } /** * @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer. */ function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) { (MathError err, Exp memory product) = mulScalar(a, scalar); if (err != MathError.NO_ERROR) { return (err, 0); } return addUInt(truncate(product), addend); } /** * @dev Divide an Exp by a scalar, returning a new Exp. */ function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) { (MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar); if (err0 != MathError.NO_ERROR) { return (err0, Exp({mantissa: 0})); } return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa})); } /** * @dev Divide a scalar by an Exp, returning a new Exp. */ function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) { /* We are doing this as: getExp(mulUInt(expScale, scalar), divisor.mantissa) How it works: Exp = a / b; Scalar = s; `s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale` */ (MathError err0, uint numerator) = mulUInt(expScale, scalar); if (err0 != MathError.NO_ERROR) { return (err0, Exp({mantissa: 0})); } return getExp(numerator, divisor.mantissa); } /** * @dev Divide a scalar by an Exp, then truncate to return an unsigned integer. */ function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) { (MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor); if (err != MathError.NO_ERROR) { return (err, 0); } return (MathError.NO_ERROR, truncate(fraction)); } /** * @dev Multiplies two exponentials, returning a new exponential. */ function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) { (MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa); if (err0 != MathError.NO_ERROR) { return (err0, Exp({mantissa: 0})); } // We add half the scale before dividing so that we get rounding instead of truncation. // See "Listing 6" and text above it at https://accu.org/index.php/journals/1717 // Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18. (MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct); if (err1 != MathError.NO_ERROR) { return (err1, Exp({mantissa: 0})); } (MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale); // The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero. assert(err2 == MathError.NO_ERROR); return (MathError.NO_ERROR, Exp({mantissa: product})); } /** * @dev Multiplies two exponentials given their mantissas, returning a new exponential. */ function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) { return mulExp(Exp({mantissa: a}), Exp({mantissa: b})); } /** * @dev Multiplies three exponentials, returning a new exponential. */ function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) { (MathError err, Exp memory ab) = mulExp(a, b); if (err != MathError.NO_ERROR) { return (err, ab); } return mulExp(ab, c); } /** * @dev Divides two exponentials, returning a new exponential. * (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b, * which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa) */ function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) { return getExp(a.mantissa, b.mantissa); } /** * @dev Truncates the given exp to a whole number value. * For example, truncate(Exp{mantissa: 15 * expScale}) = 15 */ function truncate(Exp memory exp) pure internal returns (uint) { // Note: We are not using careful math here as we're performing a division that cannot fail return exp.mantissa / expScale; } /** * @dev Checks if first Exp is less than second Exp. */ function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) { return left.mantissa < right.mantissa; } /** * @dev Checks if left Exp <= right Exp. */ function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) { return left.mantissa <= right.mantissa; } /** * @dev Checks if left Exp > right Exp. */ function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) { return left.mantissa > right.mantissa; } /** * @dev returns true if Exp is exactly zero */ function isZeroExp(Exp memory value) pure internal returns (bool) { return value.mantissa == 0; } function safe224(uint n, string memory errorMessage) pure internal returns (uint224) { require(n < 2**224, errorMessage); return uint224(n); } function safe32(uint n, string memory errorMessage) pure internal returns (uint32) { require(n < 2**32, errorMessage); return uint32(n); } function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) { return Exp({mantissa: add_(a.mantissa, b.mantissa)}); } function add_(Double memory a, Double memory b) pure internal returns (Double memory) { return Double({mantissa: add_(a.mantissa, b.mantissa)}); } function add_(uint a, uint b) pure internal returns (uint) { return add_(a, b, "addition overflow"); } function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint) { uint c = a + b; require(c >= a, errorMessage); return c; } function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) { return Exp({mantissa: sub_(a.mantissa, b.mantissa)}); } function sub_(Double memory a, Double memory b) pure internal returns (Double memory) { return Double({mantissa: sub_(a.mantissa, b.mantissa)}); } function sub_(uint a, uint b) pure internal returns (uint) { return sub_(a, b, "subtraction underflow"); } function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint) { require(b <= a, errorMessage); return a - b; } function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) { return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale}); } function mul_(Exp memory a, uint b) pure internal returns (Exp memory) { return Exp({mantissa: mul_(a.mantissa, b)}); } function mul_(uint a, Exp memory b) pure internal returns (uint) { return mul_(a, b.mantissa) / expScale; } function mul_(Double memory a, Double memory b) pure internal returns (Double memory) { return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale}); } function mul_(Double memory a, uint b) pure internal returns (Double memory) { return Double({mantissa: mul_(a.mantissa, b)}); } function mul_(uint a, Double memory b) pure internal returns (uint) { return mul_(a, b.mantissa) / doubleScale; } function mul_(uint a, uint b) pure internal returns (uint) { return mul_(a, b, "multiplication overflow"); } function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint) { if (a == 0 || b == 0) { return 0; } uint c = a * b; require(c / a == b, errorMessage); return c; } function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) { return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)}); } function div_(Exp memory a, uint b) pure internal returns (Exp memory) { return Exp({mantissa: div_(a.mantissa, b)}); } function div_(uint a, Exp memory b) pure internal returns (uint) { return div_(mul_(a, expScale), b.mantissa); } function div_(Double memory a, Double memory b) pure internal returns (Double memory) { return Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)}); } function div_(Double memory a, uint b) pure internal returns (Double memory) { return Double({mantissa: div_(a.mantissa, b)}); } function div_(uint a, Double memory b) pure internal returns (uint) { return div_(mul_(a, doubleScale), b.mantissa); } function div_(uint a, uint b) pure internal returns (uint) { return div_(a, b, "divide by zero"); } function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) { require(b > 0, errorMessage); return a / b; } function fraction(uint a, uint b) pure internal returns (Double memory) { return Double({mantissa: div_(mul_(a, doubleScale), b)}); } } // File: contracts/EIP20Interface.sol pragma solidity ^0.5.16; /** * @title ERC 20 Token Standard Interface * https://eips.ethereum.org/EIPS/eip-20 */ interface EIP20Interface { function name() external view returns (string memory); function symbol() external view returns (string memory); function decimals() external view returns (uint8); /** * @notice Get the total number of tokens in circulation * @return The supply of tokens */ function totalSupply() external view returns (uint256); /** * @notice Gets the balance of the specified address * @param owner The address from which the balance will be retrieved * @return The balance */ function balanceOf(address owner) external view returns (uint256 balance); /** * @notice Transfer `amount` tokens from `msg.sender` to `dst` * @param dst The address of the destination account * @param amount The number of tokens to transfer * @return Whether or not the transfer succeeded */ function transfer(address dst, uint256 amount) external returns (bool success); /** * @notice Transfer `amount` tokens from `src` to `dst` * @param src The address of the source account * @param dst The address of the destination account * @param amount The number of tokens to transfer * @return Whether or not the transfer succeeded */ function transferFrom(address src, address dst, uint256 amount) external returns (bool success); /** * @notice Approve `spender` to transfer up to `amount` from `src` * @dev This will overwrite the approval amount for `spender` * and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve) * @param spender The address of the account which may transfer tokens * @param amount The number of tokens that are approved (-1 means infinite) * @return Whether or not the approval succeeded */ function approve(address spender, uint256 amount) external returns (bool success); /** * @notice Get the current allowance from `owner` for `spender` * @param owner The address of the account which owns the tokens to be spent * @param spender The address of the account which may transfer tokens * @return The number of tokens allowed to be spent (-1 means infinite) */ function allowance(address owner, address spender) external view returns (uint256 remaining); event Transfer(address indexed from, address indexed to, uint256 amount); event Approval(address indexed owner, address indexed spender, uint256 amount); } // File: contracts/EIP20NonStandardInterface.sol pragma solidity ^0.5.16; /** * @title EIP20NonStandardInterface * @dev Version of ERC20 with no return values for `transfer` and `transferFrom` * See https://medium.com/coinmonks/missing-return-value-bug-at-least-130-tokens-affected-d67bf08521ca */ interface EIP20NonStandardInterface { /** * @notice Get the total number of tokens in circulation * @return The supply of tokens */ function totalSupply() external view returns (uint256); /** * @notice Gets the balance of the specified address * @param owner The address from which the balance will be retrieved * @return The balance */ function balanceOf(address owner) external view returns (uint256 balance); /// /// !!!!!!!!!!!!!! /// !!! NOTICE !!! `transfer` does not return a value, in violation of the ERC-20 specification /// !!!!!!!!!!!!!! /// /** * @notice Transfer `amount` tokens from `msg.sender` to `dst` * @param dst The address of the destination account * @param amount The number of tokens to transfer */ function transfer(address dst, uint256 amount) external; /// /// !!!!!!!!!!!!!! /// !!! NOTICE !!! `transferFrom` does not return a value, in violation of the ERC-20 specification /// !!!!!!!!!!!!!! /// /** * @notice Transfer `amount` tokens from `src` to `dst` * @param src The address of the source account * @param dst The address of the destination account * @param amount The number of tokens to transfer */ function transferFrom(address src, address dst, uint256 amount) external; /** * @notice Approve `spender` to transfer up to `amount` from `src` * @dev This will overwrite the approval amount for `spender` * and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve) * @param spender The address of the account which may transfer tokens * @param amount The number of tokens that are approved * @return Whether or not the approval succeeded */ function approve(address spender, uint256 amount) external returns (bool success); /** * @notice Get the current allowance from `owner` for `spender` * @param owner The address of the account which owns the tokens to be spent * @param spender The address of the account which may transfer tokens * @return The number of tokens allowed to be spent */ function allowance(address owner, address spender) external view returns (uint256 remaining); event Transfer(address indexed from, address indexed to, uint256 amount); event Approval(address indexed owner, address indexed spender, uint256 amount); } // File: contracts/SLToken.sol pragma solidity ^0.5.16; /** * @title SashimiLending's SLToken Contract * @notice Abstract base for SLTokens * @author SashimiLending */ contract SLToken is SLTokenInterface, Exponential, TokenErrorReporter { /** * @notice Initialize the money market * @param comptroller_ The address of the Comptroller * @param interestRateModel_ The address of the interest rate model * @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18 * @param name_ EIP-20 name of this token * @param symbol_ EIP-20 symbol of this token * @param decimals_ EIP-20 decimal precision of this token */ function initialize(ComptrollerInterface comptroller_, InterestRateModel interestRateModel_, uint initialExchangeRateMantissa_, string memory name_, string memory symbol_, uint8 decimals_) public { require(msg.sender == admin, "only admin may initialize the market"); require(accrualBlockNumber == 0 && borrowIndex == 0, "market may only be initialized once"); // Set initial exchange rate initialExchangeRateMantissa = initialExchangeRateMantissa_; require(initialExchangeRateMantissa > 0, "initial exchange rate must be greater than zero."); // Set the comptroller uint err = _setComptroller(comptroller_); require(err == uint(Error.NO_ERROR), "setting comptroller failed"); // Initialize block number and borrow index (block number mocks depend on comptroller being set) accrualBlockNumber = getBlockNumber(); borrowIndex = mantissaOne; // Set the interest rate model (depends on block number / borrow index) err = _setInterestRateModelFresh(interestRateModel_); require(err == uint(Error.NO_ERROR), "setting interest rate model failed"); name = name_; symbol = symbol_; decimals = decimals_; // The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund) _notEntered = true; } /** * @notice Transfer `tokens` tokens from `src` to `dst` by `spender` * @dev Called by both `transfer` and `transferFrom` internally * @param spender The address of the account performing the transfer * @param src The address of the source account * @param dst The address of the destination account * @param tokens The number of tokens to transfer * @return Whether or not the transfer succeeded */ function transferTokens(address spender, address src, address dst, uint tokens) internal returns (uint) { /* Fail if transfer not allowed */ uint allowed = comptroller.transferAllowed(address(this), src, dst, tokens); if (allowed != 0) { return failOpaque(Error.COMPTROLLER_REJECTION, FailureInfo.TRANSFER_COMPTROLLER_REJECTION, allowed); } /* Do not allow self-transfers */ if (src == dst) { return fail(Error.BAD_INPUT, FailureInfo.TRANSFER_NOT_ALLOWED); } /* Get the allowance, infinite for the account owner */ uint startingAllowance = 0; if (spender == src) { startingAllowance = uint(-1); } else { startingAllowance = transferAllowances[src][spender]; } /* Do the calculations, checking for {under,over}flow */ MathError mathErr; uint allowanceNew; uint srcTokensNew; uint dstTokensNew; (mathErr, allowanceNew) = subUInt(startingAllowance, tokens); if (mathErr != MathError.NO_ERROR) { return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ALLOWED); } (mathErr, srcTokensNew) = subUInt(accountTokens[src], tokens); if (mathErr != MathError.NO_ERROR) { return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_NOT_ENOUGH); } (mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens); if (mathErr != MathError.NO_ERROR) { return fail(Error.MATH_ERROR, FailureInfo.TRANSFER_TOO_MUCH); } ///////////////////////// // EFFECTS & INTERACTIONS // (No safe failures beyond this point) accountTokens[src] = srcTokensNew; accountTokens[dst] = dstTokensNew; /* Eat some of the allowance (if necessary) */ if (startingAllowance != uint(-1)) { transferAllowances[src][spender] = allowanceNew; } /* We emit a Transfer event */ emit Transfer(src, dst, tokens); comptroller.transferVerify(address(this), src, dst, tokens); return uint(Error.NO_ERROR); } /** * @notice Transfer `amount` tokens from `msg.sender` to `dst` * @param dst The address of the destination account * @param amount The number of tokens to transfer * @return Whether or not the transfer succeeded */ function transfer(address dst, uint256 amount) external nonReentrant returns (bool) { return transferTokens(msg.sender, msg.sender, dst, amount) == uint(Error.NO_ERROR); } /** * @notice Transfer `amount` tokens from `src` to `dst` * @param src The address of the source account * @param dst The address of the destination account * @param amount The number of tokens to transfer * @return Whether or not the transfer succeeded */ function transferFrom(address src, address dst, uint256 amount) external nonReentrant returns (bool) { return transferTokens(msg.sender, src, dst, amount) == uint(Error.NO_ERROR); } /** * @notice Approve `spender` to transfer up to `amount` from `src` * @dev This will overwrite the approval amount for `spender` * and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve) * @param spender The address of the account which may transfer tokens * @param amount The number of tokens that are approved (-1 means infinite) * @return Whether or not the approval succeeded */ function approve(address spender, uint256 amount) external returns (bool) { address src = msg.sender; transferAllowances[src][spender] = amount; emit Approval(src, spender, amount); return true; } /** * @notice Get the current allowance from `owner` for `spender` * @param owner The address of the account which owns the tokens to be spent * @param spender The address of the account which may transfer tokens * @return The number of tokens allowed to be spent (-1 means infinite) */ function allowance(address owner, address spender) external view returns (uint256) { return transferAllowances[owner][spender]; } /** * @notice Get the token balance of the `owner` * @param owner The address of the account to query * @return The number of tokens owned by `owner` */ function balanceOf(address owner) external view returns (uint256) { return accountTokens[owner]; } /** * @notice Get the underlying balance of the `owner` * @dev This also accrues interest in a transaction * @param owner The address of the account to query * @return The amount of underlying owned by `owner` */ function balanceOfUnderlying(address owner) external returns (uint) { Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()}); (MathError mErr, uint balance) = mulScalarTruncate(exchangeRate, accountTokens[owner]); require(mErr == MathError.NO_ERROR, "balance could not be calculated"); return balance; } /** * @notice Get a snapshot of the account's balances, and the cached exchange rate * @dev This is used by comptroller to more efficiently perform liquidity checks. * @param account Address of the account to snapshot * @return (possible error, token balance, borrow balance, exchange rate mantissa) */ function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint) { uint slTokenBalance = accountTokens[account]; uint borrowBalance; uint exchangeRateMantissa; MathError mErr; (mErr, borrowBalance) = borrowBalanceStoredInternal(account); if (mErr != MathError.NO_ERROR) { return (uint(Error.MATH_ERROR), 0, 0, 0); } (mErr, exchangeRateMantissa) = exchangeRateStoredInternal(); if (mErr != MathError.NO_ERROR) { return (uint(Error.MATH_ERROR), 0, 0, 0); } return (uint(Error.NO_ERROR), slTokenBalance, borrowBalance, exchangeRateMantissa); } /** * @dev Function to simply retrieve block number * This exists mainly for inheriting test contracts to stub this result. */ function getBlockNumber() internal view returns (uint) { return block.number; } /** * @notice Returns the current per-block borrow interest rate for this slToken * @return The borrow interest rate per block, scaled by 1e18 */ function borrowRatePerBlock() external view returns (uint) { return interestRateModel.getBorrowRate(getCashPrior(), totalBorrows, totalReserves); } /** * @notice Returns the current per-block supply interest rate for this slToken * @return The supply interest rate per block, scaled by 1e18 */ function supplyRatePerBlock() external view returns (uint) { return interestRateModel.getSupplyRate(getCashPrior(), totalBorrows, totalReserves, reserveFactorMantissa); } /** * @notice Returns the current total borrows plus accrued interest * @return The total borrows with interest */ function totalBorrowsCurrent() external nonReentrant returns (uint) { require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed"); return totalBorrows; } /** * @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex * @param account The address whose balance should be calculated after updating borrowIndex * @return The calculated balance */ function borrowBalanceCurrent(address account) external nonReentrant returns (uint) { require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed"); return borrowBalanceStored(account); } /** * @notice Return the borrow balance of account based on stored data * @param account The address whose balance should be calculated * @return The calculated balance */ function borrowBalanceStored(address account) public view returns (uint) { (MathError err, uint result) = borrowBalanceStoredInternal(account); require(err == MathError.NO_ERROR, "borrowBalanceStored: borrowBalanceStoredInternal failed"); return result; } /** * @notice Return the borrow balance of account based on stored data * @param account The address whose balance should be calculated * @return (error code, the calculated balance or 0 if error code is non-zero) */ function borrowBalanceStoredInternal(address account) internal view returns (MathError, uint) { /* Note: we do not assert that the market is up to date */ MathError mathErr; uint principalTimesIndex; uint result; /* Get borrowBalance and borrowIndex */ BorrowSnapshot storage borrowSnapshot = accountBorrows[account]; /* If borrowBalance = 0 then borrowIndex is likely also 0. * Rather than failing the calculation with a division by 0, we immediately return 0 in this case. */ if (borrowSnapshot.principal == 0) { return (MathError.NO_ERROR, 0); } /* Calculate new borrow balance using the interest index: * recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex */ (mathErr, principalTimesIndex) = mulUInt(borrowSnapshot.principal, borrowIndex); if (mathErr != MathError.NO_ERROR) { return (mathErr, 0); } (mathErr, result) = divUInt(principalTimesIndex, borrowSnapshot.interestIndex); if (mathErr != MathError.NO_ERROR) { return (mathErr, 0); } return (MathError.NO_ERROR, result); } /** * @notice Accrue interest then return the up-to-date exchange rate * @return Calculated exchange rate scaled by 1e18 */ function exchangeRateCurrent() public nonReentrant returns (uint) { require(accrueInterest() == uint(Error.NO_ERROR), "accrue interest failed"); return exchangeRateStored(); } /** * @notice Calculates the exchange rate from the underlying to the SLToken * @dev This function does not accrue interest before calculating the exchange rate * @return Calculated exchange rate scaled by 1e18 */ function exchangeRateStored() public view returns (uint) { (MathError err, uint result) = exchangeRateStoredInternal(); require(err == MathError.NO_ERROR, "exchangeRateStored: exchangeRateStoredInternal failed"); return result; } /** * @notice Calculates the exchange rate from the underlying to the SLToken * @dev This function does not accrue interest before calculating the exchange rate * @return (error code, calculated exchange rate scaled by 1e18) */ function exchangeRateStoredInternal() internal view returns (MathError, uint) { uint _totalSupply = totalSupply; if (_totalSupply == 0) { /* * If there are no tokens minted: * exchangeRate = initialExchangeRate */ return (MathError.NO_ERROR, initialExchangeRateMantissa); } else { /* * Otherwise: * exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply */ uint totalCash = getCashPrior(); uint cashPlusBorrowsMinusReserves; Exp memory exchangeRate; MathError mathErr; (mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(totalCash, totalBorrows, totalReserves); if (mathErr != MathError.NO_ERROR) { return (mathErr, 0); } (mathErr, exchangeRate) = getExp(cashPlusBorrowsMinusReserves, _totalSupply); if (mathErr != MathError.NO_ERROR) { return (mathErr, 0); } return (MathError.NO_ERROR, exchangeRate.mantissa); } } /** * @notice Get cash balance of this slToken in the underlying asset * @return The quantity of underlying asset owned by this contract */ function getCash() external view returns (uint) { return getCashPrior(); } /** * @notice Applies accrued interest to total borrows and reserves * @dev This calculates interest accrued from the last checkpointed block * up to the current block and writes new checkpoint to storage. */ function accrueInterest() public returns (uint) { /* Remember the initial block number */ uint currentBlockNumber = getBlockNumber(); uint accrualBlockNumberPrior = accrualBlockNumber; /* Short-circuit accumulating 0 interest */ if (accrualBlockNumberPrior == currentBlockNumber) { return uint(Error.NO_ERROR); } /* Read the previous values out of storage */ uint cashPrior = getCashPrior(); uint borrowsPrior = totalBorrows; uint reservesPrior = totalReserves; uint borrowIndexPrior = borrowIndex; /* Calculate the current borrow interest rate */ uint borrowRateMantissa = interestRateModel.getBorrowRate(cashPrior, borrowsPrior, reservesPrior); require(borrowRateMantissa <= borrowRateMaxMantissa, "borrow rate is absurdly high"); /* Calculate the number of blocks elapsed since the last accrual */ (MathError mathErr, uint blockDelta) = subUInt(currentBlockNumber, accrualBlockNumberPrior); require(mathErr == MathError.NO_ERROR, "could not calculate block delta"); /* * Calculate the interest accumulated into borrows and reserves and the new index: * simpleInterestFactor = borrowRate * blockDelta * interestAccumulated = simpleInterestFactor * totalBorrows * totalBorrowsNew = interestAccumulated + totalBorrows * totalReservesNew = interestAccumulated * reserveFactor + totalReserves * borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex */ Exp memory simpleInterestFactor; uint interestAccumulated; uint totalBorrowsNew; uint totalReservesNew; uint borrowIndexNew; (mathErr, simpleInterestFactor) = mulScalar(Exp({mantissa: borrowRateMantissa}), blockDelta); if (mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED, uint(mathErr)); } (mathErr, interestAccumulated) = mulScalarTruncate(simpleInterestFactor, borrowsPrior); if (mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED, uint(mathErr)); } (mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior); if (mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED, uint(mathErr)); } (mathErr, totalReservesNew) = mulScalarTruncateAddUInt(Exp({mantissa: reserveFactorMantissa}), interestAccumulated, reservesPrior); if (mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED, uint(mathErr)); } (mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(simpleInterestFactor, borrowIndexPrior, borrowIndexPrior); if (mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED, uint(mathErr)); } ///////////////////////// // EFFECTS & INTERACTIONS // (No safe failures beyond this point) /* We write the previously calculated values into storage */ accrualBlockNumber = currentBlockNumber; borrowIndex = borrowIndexNew; totalBorrows = totalBorrowsNew; totalReserves = totalReservesNew; /* We emit an AccrueInterest event */ emit AccrueInterest(cashPrior, interestAccumulated, borrowIndexNew, totalBorrowsNew); return uint(Error.NO_ERROR); } /** * @notice Sender supplies assets into the market and receives slTokens in exchange * @dev Accrues interest whether or not the operation succeeds, unless reverted * @param mintAmount The amount of the underlying asset to supply * @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount. */ function mintInternal(uint mintAmount) internal nonReentrant returns (uint, uint) { uint error = accrueInterest(); if (error != uint(Error.NO_ERROR)) { // accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed return (fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED), 0); } // mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to return mintFresh(msg.sender, mintAmount); } struct MintLocalVars { Error err; MathError mathErr; uint exchangeRateMantissa; uint mintTokens; uint totalSupplyNew; uint accountTokensNew; uint actualMintAmount; } /** * @notice User supplies assets into the market and receives slTokens in exchange * @dev Assumes interest has already been accrued up to the current block * @param minter The address of the account which is supplying the assets * @param mintAmount The amount of the underlying asset to supply * @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount. */ function mintFresh(address minter, uint mintAmount) internal returns (uint, uint) { /* Fail if mint not allowed */ uint allowed = comptroller.mintAllowed(address(this), minter, mintAmount); if (allowed != 0) { return (failOpaque(Error.COMPTROLLER_REJECTION, FailureInfo.MINT_COMPTROLLER_REJECTION, allowed), 0); } /* Verify market's block number equals current block number */ if (accrualBlockNumber != getBlockNumber()) { return (fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK), 0); } MintLocalVars memory vars; (vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal(); if (vars.mathErr != MathError.NO_ERROR) { return (failOpaque(Error.MATH_ERROR, FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)), 0); } ///////////////////////// // EFFECTS & INTERACTIONS // (No safe failures beyond this point) /* * We call `doTransferIn` for the minter and the mintAmount. * Note: The slToken must handle variations between ERC-20 and ETH underlying. * `doTransferIn` reverts if anything goes wrong, since we can't be sure if * side-effects occurred. The function returns the amount actually transferred, * in case of a fee. On success, the slToken holds an additional `actualMintAmount` * of cash. */ vars.actualMintAmount = doTransferIn(minter, mintAmount); /* * We get the current exchange rate and calculate the number of slTokens to be minted: * mintTokens = actualMintAmount / exchangeRate */ (vars.mathErr, vars.mintTokens) = divScalarByExpTruncate(vars.actualMintAmount, Exp({mantissa: vars.exchangeRateMantissa})); require(vars.mathErr == MathError.NO_ERROR, "MINT_EXCHANGE_CALCULATION_FAILED"); /* * We calculate the new total supply of slTokens and minter token balance, checking for overflow: * totalSupplyNew = totalSupply + mintTokens * accountTokensNew = accountTokens[minter] + mintTokens */ (vars.mathErr, vars.totalSupplyNew) = addUInt(totalSupply, vars.mintTokens); require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED"); (vars.mathErr, vars.accountTokensNew) = addUInt(accountTokens[minter], vars.mintTokens); require(vars.mathErr == MathError.NO_ERROR, "MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED"); /* We write previously calculated values into storage */ totalSupply = vars.totalSupplyNew; accountTokens[minter] = vars.accountTokensNew; /* We emit a Mint event, and a Transfer event */ emit Mint(minter, vars.actualMintAmount, vars.mintTokens); emit Transfer(address(this), minter, vars.mintTokens); /* We call the defense hook */ comptroller.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens); return (uint(Error.NO_ERROR), vars.actualMintAmount); } /** * @notice Sender redeems slTokens in exchange for the underlying asset * @dev Accrues interest whether or not the operation succeeds, unless reverted * @param redeemTokens The number of slTokens to redeem into underlying * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function redeemInternal(uint redeemTokens) internal nonReentrant returns (uint) { uint error = accrueInterest(); if (error != uint(Error.NO_ERROR)) { // accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED); } // redeemFresh emits redeem-specific logs on errors, so we don't need to return redeemFresh(msg.sender, redeemTokens, 0); } /** * @notice Sender redeems slTokens in exchange for a specified amount of underlying asset * @dev Accrues interest whether or not the operation succeeds, unless reverted * @param redeemAmount The amount of underlying to receive from redeeming slTokens * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function redeemUnderlyingInternal(uint redeemAmount) internal nonReentrant returns (uint) { uint error = accrueInterest(); if (error != uint(Error.NO_ERROR)) { // accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed return fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED); } // redeemFresh emits redeem-specific logs on errors, so we don't need to return redeemFresh(msg.sender, 0, redeemAmount); } struct RedeemLocalVars { Error err; MathError mathErr; uint exchangeRateMantissa; uint redeemTokens; uint redeemAmount; uint totalSupplyNew; uint accountTokensNew; } /** * @notice User redeems slTokens in exchange for the underlying asset * @dev Assumes interest has already been accrued up to the current block * @param redeemer The address of the account which is redeeming the tokens * @param redeemTokensIn The number of slTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero) * @param redeemAmountIn The number of underlying tokens to receive from redeeming slTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero) * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function redeemFresh(address payable redeemer, uint redeemTokensIn, uint redeemAmountIn) internal returns (uint) { require(redeemTokensIn == 0 || redeemAmountIn == 0, "one of redeemTokensIn or redeemAmountIn must be zero"); RedeemLocalVars memory vars; /* exchangeRate = invoke Exchange Rate Stored() */ (vars.mathErr, vars.exchangeRateMantissa) = exchangeRateStoredInternal(); if (vars.mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED, uint(vars.mathErr)); } /* If redeemTokensIn > 0: */ if (redeemTokensIn > 0) { /* * We calculate the exchange rate and the amount of underlying to be redeemed: * redeemTokens = redeemTokensIn * redeemAmount = redeemTokensIn x exchangeRateCurrent */ vars.redeemTokens = redeemTokensIn; (vars.mathErr, vars.redeemAmount) = mulScalarTruncate(Exp({mantissa: vars.exchangeRateMantissa}), redeemTokensIn); if (vars.mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED, uint(vars.mathErr)); } } else { /* * We get the current exchange rate and calculate the amount to be redeemed: * redeemTokens = redeemAmountIn / exchangeRate * redeemAmount = redeemAmountIn */ (vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(redeemAmountIn, Exp({mantissa: vars.exchangeRateMantissa})); if (vars.mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED, uint(vars.mathErr)); } vars.redeemAmount = redeemAmountIn; } /* Fail if redeem not allowed */ uint allowed = comptroller.redeemAllowed(address(this), redeemer, vars.redeemTokens); if (allowed != 0) { return failOpaque(Error.COMPTROLLER_REJECTION, FailureInfo.REDEEM_COMPTROLLER_REJECTION, allowed); } /* Verify market's block number equals current block number */ if (accrualBlockNumber != getBlockNumber()) { return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDEEM_FRESHNESS_CHECK); } /* * We calculate the new total supply and redeemer balance, checking for underflow: * totalSupplyNew = totalSupply - redeemTokens * accountTokensNew = accountTokens[redeemer] - redeemTokens */ (vars.mathErr, vars.totalSupplyNew) = subUInt(totalSupply, vars.redeemTokens); if (vars.mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED, uint(vars.mathErr)); } (vars.mathErr, vars.accountTokensNew) = subUInt(accountTokens[redeemer], vars.redeemTokens); if (vars.mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)); } /* Fail gracefully if protocol has insufficient cash */ if (getCashPrior() < vars.redeemAmount) { return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE); } ///////////////////////// // EFFECTS & INTERACTIONS // (No safe failures beyond this point) /* * We invoke doTransferOut for the redeemer and the redeemAmount. * Note: The slToken must handle variations between ERC-20 and ETH underlying. * On success, the slToken has redeemAmount less of cash. * doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred. */ doTransferOut(redeemer, vars.redeemAmount); /* We write previously calculated values into storage */ totalSupply = vars.totalSupplyNew; accountTokens[redeemer] = vars.accountTokensNew; /* We emit a Transfer event, and a Redeem event */ emit Transfer(redeemer, address(this), vars.redeemTokens); emit Redeem(redeemer, vars.redeemAmount, vars.redeemTokens); /* We call the defense hook */ comptroller.redeemVerify(address(this), redeemer, vars.redeemAmount, vars.redeemTokens); return uint(Error.NO_ERROR); } /** * @notice Sender borrows assets from the protocol to their own address * @param borrowAmount The amount of the underlying asset to borrow * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function borrowInternal(uint borrowAmount) internal nonReentrant returns (uint) { uint error = accrueInterest(); if (error != uint(Error.NO_ERROR)) { // accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed return fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED); } // borrowFresh emits borrow-specific logs on errors, so we don't need to return borrowFresh(msg.sender, borrowAmount); } struct BorrowLocalVars { MathError mathErr; uint accountBorrows; uint accountBorrowsNew; uint totalBorrowsNew; } /** * @notice Users borrow assets from the protocol to their own address * @param borrowAmount The amount of the underlying asset to borrow * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function borrowFresh(address payable borrower, uint borrowAmount) internal returns (uint) { /* Fail if borrow not allowed */ uint allowed = comptroller.borrowAllowed(address(this), borrower, borrowAmount); if (allowed != 0) { return failOpaque(Error.COMPTROLLER_REJECTION, FailureInfo.BORROW_COMPTROLLER_REJECTION, allowed); } /* Verify market's block number equals current block number */ if (accrualBlockNumber != getBlockNumber()) { return fail(Error.MARKET_NOT_FRESH, FailureInfo.BORROW_FRESHNESS_CHECK); } /* Fail gracefully if protocol has insufficient underlying cash */ if (getCashPrior() < borrowAmount) { return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.BORROW_CASH_NOT_AVAILABLE); } BorrowLocalVars memory vars; /* * We calculate the new borrower and total borrow balances, failing on overflow: * accountBorrowsNew = accountBorrows + borrowAmount * totalBorrowsNew = totalBorrows + borrowAmount */ (vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower); if (vars.mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)); } (vars.mathErr, vars.accountBorrowsNew) = addUInt(vars.accountBorrows, borrowAmount); if (vars.mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)); } (vars.mathErr, vars.totalBorrowsNew) = addUInt(totalBorrows, borrowAmount); if (vars.mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)); } ///////////////////////// // EFFECTS & INTERACTIONS // (No safe failures beyond this point) /* * We invoke doTransferOut for the borrower and the borrowAmount. * Note: The slToken must handle variations between ERC-20 and ETH underlying. * On success, the slToken borrowAmount less of cash. * doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred. */ doTransferOut(borrower, borrowAmount); /* We write the previously calculated values into storage */ accountBorrows[borrower].principal = vars.accountBorrowsNew; accountBorrows[borrower].interestIndex = borrowIndex; totalBorrows = vars.totalBorrowsNew; /* We emit a Borrow event */ emit Borrow(borrower, borrowAmount, vars.accountBorrowsNew, vars.totalBorrowsNew); /* We call the defense hook */ comptroller.borrowVerify(address(this), borrower, borrowAmount); return uint(Error.NO_ERROR); } /** * @notice Sender repays their own borrow * @param repayAmount The amount to repay * @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount. */ function repayBorrowInternal(uint repayAmount) internal nonReentrant returns (uint, uint) { uint error = accrueInterest(); if (error != uint(Error.NO_ERROR)) { // accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed return (fail(Error(error), FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED), 0); } // repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to return repayBorrowFresh(msg.sender, msg.sender, repayAmount); } /** * @notice Sender repays a borrow belonging to borrower * @param borrower the account with the debt being payed off * @param repayAmount The amount to repay * @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount. */ function repayBorrowBehalfInternal(address borrower, uint repayAmount) internal nonReentrant returns (uint, uint) { uint error = accrueInterest(); if (error != uint(Error.NO_ERROR)) { // accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed return (fail(Error(error), FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED), 0); } // repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to return repayBorrowFresh(msg.sender, borrower, repayAmount); } struct RepayBorrowLocalVars { Error err; MathError mathErr; uint repayAmount; uint borrowerIndex; uint accountBorrows; uint accountBorrowsNew; uint totalBorrowsNew; uint actualRepayAmount; } /** * @notice Borrows are repaid by another user (possibly the borrower). * @param payer the account paying off the borrow * @param borrower the account with the debt being payed off * @param repayAmount the amount of undelrying tokens being returned * @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount. */ function repayBorrowFresh(address payer, address borrower, uint repayAmount) internal returns (uint, uint) { /* Fail if repayBorrow not allowed */ uint allowed = comptroller.repayBorrowAllowed(address(this), payer, borrower, repayAmount); if (allowed != 0) { return (failOpaque(Error.COMPTROLLER_REJECTION, FailureInfo.REPAY_BORROW_COMPTROLLER_REJECTION, allowed), 0); } /* Verify market's block number equals current block number */ if (accrualBlockNumber != getBlockNumber()) { return (fail(Error.MARKET_NOT_FRESH, FailureInfo.REPAY_BORROW_FRESHNESS_CHECK), 0); } RepayBorrowLocalVars memory vars; /* We remember the original borrowerIndex for verification purposes */ vars.borrowerIndex = accountBorrows[borrower].interestIndex; /* We fetch the amount the borrower owes, with accumulated interest */ (vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(borrower); if (vars.mathErr != MathError.NO_ERROR) { return (failOpaque(Error.MATH_ERROR, FailureInfo.REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED, uint(vars.mathErr)), 0); } /* If repayAmount == -1, repayAmount = accountBorrows */ if (repayAmount == uint(-1)) { vars.repayAmount = vars.accountBorrows; } else { vars.repayAmount = repayAmount; } ///////////////////////// // EFFECTS & INTERACTIONS // (No safe failures beyond this point) /* * We call doTransferIn for the payer and the repayAmount * Note: The slToken must handle variations between ERC-20 and ETH underlying. * On success, the slToken holds an additional repayAmount of cash. * doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred. * it returns the amount actually transferred, in case of a fee. */ vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount); /* * We calculate the new borrower and total borrow balances, failing on underflow: * accountBorrowsNew = accountBorrows - actualRepayAmount * totalBorrowsNew = totalBorrows - actualRepayAmount */ (vars.mathErr, vars.accountBorrowsNew) = subUInt(vars.accountBorrows, vars.actualRepayAmount); require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED"); (vars.mathErr, vars.totalBorrowsNew) = subUInt(totalBorrows, vars.actualRepayAmount); require(vars.mathErr == MathError.NO_ERROR, "REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED"); /* We write the previously calculated values into storage */ accountBorrows[borrower].principal = vars.accountBorrowsNew; accountBorrows[borrower].interestIndex = borrowIndex; totalBorrows = vars.totalBorrowsNew; /* We emit a RepayBorrow event */ emit RepayBorrow(payer, borrower, vars.actualRepayAmount, vars.accountBorrowsNew, vars.totalBorrowsNew); /* We call the defense hook */ comptroller.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex); return (uint(Error.NO_ERROR), vars.actualRepayAmount); } /** * @notice The sender liquidates the borrowers collateral. * The collateral seized is transferred to the liquidator. * @param borrower The borrower of this slToken to be liquidated * @param slTokenCollateral The market in which to seize collateral from the borrower * @param repayAmount The amount of the underlying borrowed asset to repay * @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount. */ function liquidateBorrowInternal(address borrower, uint repayAmount, SLTokenInterface slTokenCollateral) internal nonReentrant returns (uint, uint) { uint error = accrueInterest(); if (error != uint(Error.NO_ERROR)) { // accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED), 0); } error = slTokenCollateral.accrueInterest(); if (error != uint(Error.NO_ERROR)) { // accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed return (fail(Error(error), FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED), 0); } // liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to return liquidateBorrowFresh(msg.sender, borrower, repayAmount, slTokenCollateral); } /** * @notice The liquidator liquidates the borrowers collateral. * The collateral seized is transferred to the liquidator. * @param borrower The borrower of this slToken to be liquidated * @param liquidator The address repaying the borrow and seizing collateral * @param slTokenCollateral The market in which to seize collateral from the borrower * @param repayAmount The amount of the underlying borrowed asset to repay * @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount. */ function liquidateBorrowFresh(address liquidator, address borrower, uint repayAmount, SLTokenInterface slTokenCollateral) internal returns (uint, uint) { /* Fail if liquidate not allowed */ uint allowed = comptroller.liquidateBorrowAllowed(address(this), address(slTokenCollateral), liquidator, borrower, repayAmount); if (allowed != 0) { return (failOpaque(Error.COMPTROLLER_REJECTION, FailureInfo.LIQUIDATE_COMPTROLLER_REJECTION, allowed), 0); } /* Verify market's block number equals current block number */ if (accrualBlockNumber != getBlockNumber()) { return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_FRESHNESS_CHECK), 0); } /* Verify slTokenCollateral market's block number equals current block number */ if (slTokenCollateral.accrualBlockNumber() != getBlockNumber()) { return (fail(Error.MARKET_NOT_FRESH, FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK), 0); } /* Fail if borrower = liquidator */ if (borrower == liquidator) { return (fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER), 0); } /* Fail if repayAmount = 0 */ if (repayAmount == 0) { return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO), 0); } /* Fail if repayAmount = -1 */ if (repayAmount == uint(-1)) { return (fail(Error.INVALID_CLOSE_AMOUNT_REQUESTED, FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX), 0); } /* Fail if repayBorrow fails */ (uint repayBorrowError, uint actualRepayAmount) = repayBorrowFresh(liquidator, borrower, repayAmount); if (repayBorrowError != uint(Error.NO_ERROR)) { return (fail(Error(repayBorrowError), FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED), 0); } ///////////////////////// // EFFECTS & INTERACTIONS // (No safe failures beyond this point) /* We calculate the number of collateral tokens that will be seized */ (uint amountSeizeError, uint seizeTokens) = comptroller.liquidateCalculateSeizeTokens(address(this), address(slTokenCollateral), actualRepayAmount); require(amountSeizeError == uint(Error.NO_ERROR), "LIQUIDATE_COMPTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED"); /* Revert if borrower collateral token balance < seizeTokens */ require(slTokenCollateral.balanceOf(borrower) >= seizeTokens, "LIQUIDATE_SEIZE_TOO_MUCH"); // If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call uint seizeError; if (address(slTokenCollateral) == address(this)) { seizeError = seizeInternal(address(this), liquidator, borrower, seizeTokens); } else { seizeError = slTokenCollateral.seize(liquidator, borrower, seizeTokens); } /* Revert if seize tokens fails (since we cannot be sure of side effects) */ require(seizeError == uint(Error.NO_ERROR), "token seizure failed"); /* We emit a LiquidateBorrow event */ emit LiquidateBorrow(liquidator, borrower, actualRepayAmount, address(slTokenCollateral), seizeTokens); /* We call the defense hook */ comptroller.liquidateBorrowVerify(address(this), address(slTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens); return (uint(Error.NO_ERROR), actualRepayAmount); } /** * @notice Transfers collateral tokens (this market) to the liquidator. * @dev Will fail unless called by another slToken during the process of liquidation. * Its absolutely critical to use msg.sender as the borrowed slToken and not a parameter. * @param liquidator The account receiving seized collateral * @param borrower The account having collateral seized * @param seizeTokens The number of slTokens to seize * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function seize(address liquidator, address borrower, uint seizeTokens) external nonReentrant returns (uint) { return seizeInternal(msg.sender, liquidator, borrower, seizeTokens); } /** * @notice Transfers collateral tokens (this market) to the liquidator. * @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another SLToken. * Its absolutely critical to use msg.sender as the seizer slToken and not a parameter. * @param seizerToken The contract seizing the collateral (i.e. borrowed slToken) * @param liquidator The account receiving seized collateral * @param borrower The account having collateral seized * @param seizeTokens The number of slTokens to seize * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function seizeInternal(address seizerToken, address liquidator, address borrower, uint seizeTokens) internal returns (uint) { /* Fail if seize not allowed */ uint allowed = comptroller.seizeAllowed(address(this), seizerToken, liquidator, borrower, seizeTokens); if (allowed != 0) { return failOpaque(Error.COMPTROLLER_REJECTION, FailureInfo.LIQUIDATE_SEIZE_COMPTROLLER_REJECTION, allowed); } /* Fail if borrower = liquidator */ if (borrower == liquidator) { return fail(Error.INVALID_ACCOUNT_PAIR, FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER); } MathError mathErr; uint borrowerTokensNew; uint liquidatorTokensNew; /* * We calculate the new borrower and liquidator token balances, failing on underflow/overflow: * borrowerTokensNew = accountTokens[borrower] - seizeTokens * liquidatorTokensNew = accountTokens[liquidator] + seizeTokens */ (mathErr, borrowerTokensNew) = subUInt(accountTokens[borrower], seizeTokens); if (mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED, uint(mathErr)); } (mathErr, liquidatorTokensNew) = addUInt(accountTokens[liquidator], seizeTokens); if (mathErr != MathError.NO_ERROR) { return failOpaque(Error.MATH_ERROR, FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED, uint(mathErr)); } ///////////////////////// // EFFECTS & INTERACTIONS // (No safe failures beyond this point) /* We write the previously calculated values into storage */ accountTokens[borrower] = borrowerTokensNew; accountTokens[liquidator] = liquidatorTokensNew; /* Emit a Transfer event */ emit Transfer(borrower, liquidator, seizeTokens); /* We call the defense hook */ comptroller.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens); return uint(Error.NO_ERROR); } /*** Admin Functions ***/ /** * @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer. * @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer. * @param newPendingAdmin New pending admin. * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function _setPendingAdmin(address payable newPendingAdmin) external returns (uint) { // Check caller = admin if (msg.sender != admin) { return fail(Error.UNAUTHORIZED, FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK); } // Save current value, if any, for inclusion in log address oldPendingAdmin = pendingAdmin; // Store pendingAdmin with value newPendingAdmin pendingAdmin = newPendingAdmin; // Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin) emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin); return uint(Error.NO_ERROR); } /** * @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin * @dev Admin function for pending admin to accept role and update admin * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function _acceptAdmin() external returns (uint) { // Check caller is pendingAdmin and pendingAdmin ≠ address(0) if (msg.sender != pendingAdmin || msg.sender == address(0)) { return fail(Error.UNAUTHORIZED, FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK); } // Save current values for inclusion in log address oldAdmin = admin; address oldPendingAdmin = pendingAdmin; // Store admin with value pendingAdmin admin = pendingAdmin; // Clear the pending value pendingAdmin = address(0); emit NewAdmin(oldAdmin, admin); emit NewPendingAdmin(oldPendingAdmin, pendingAdmin); return uint(Error.NO_ERROR); } /** * @notice Sets a new comptroller for the market * @dev Admin function to set a new comptroller * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function _setComptroller(ComptrollerInterface newComptroller) public returns (uint) { // Check caller is admin if (msg.sender != admin) { return fail(Error.UNAUTHORIZED, FailureInfo.SET_COMPTROLLER_OWNER_CHECK); } ComptrollerInterface oldComptroller = comptroller; // Ensure invoke comptroller.isComptroller() returns true require(newComptroller.isComptroller(), "marker method returned false"); // Set market's comptroller to newComptroller comptroller = newComptroller; // Emit NewComptroller(oldComptroller, newComptroller) emit NewComptroller(oldComptroller, newComptroller); return uint(Error.NO_ERROR); } /** * @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh * @dev Admin function to accrue interest and set a new reserve factor * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function _setReserveFactor(uint newReserveFactorMantissa) external nonReentrant returns (uint) { uint error = accrueInterest(); if (error != uint(Error.NO_ERROR)) { // accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed. return fail(Error(error), FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED); } // _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to. return _setReserveFactorFresh(newReserveFactorMantissa); } /** * @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual) * @dev Admin function to set a new reserve factor * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function _setReserveFactorFresh(uint newReserveFactorMantissa) internal returns (uint) { // Check caller is admin if (msg.sender != admin) { return fail(Error.UNAUTHORIZED, FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK); } // Verify market's block number equals current block number if (accrualBlockNumber != getBlockNumber()) { return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK); } // Check newReserveFactor ≤ maxReserveFactor if (newReserveFactorMantissa > reserveFactorMaxMantissa) { return fail(Error.BAD_INPUT, FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK); } uint oldReserveFactorMantissa = reserveFactorMantissa; reserveFactorMantissa = newReserveFactorMantissa; emit NewReserveFactor(oldReserveFactorMantissa, newReserveFactorMantissa); return uint(Error.NO_ERROR); } /** * @notice Accrues interest and reduces reserves by transferring from msg.sender * @param addAmount Amount of addition to reserves * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function _addReservesInternal(uint addAmount) internal nonReentrant returns (uint) { uint error = accrueInterest(); if (error != uint(Error.NO_ERROR)) { // accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed. return fail(Error(error), FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED); } // _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to. (error, ) = _addReservesFresh(addAmount); return error; } /** * @notice Add reserves by transferring from caller * @dev Requires fresh interest accrual * @param addAmount Amount of addition to reserves * @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees */ function _addReservesFresh(uint addAmount) internal returns (uint, uint) { // totalReserves + actualAddAmount uint totalReservesNew; uint actualAddAmount; // We fail gracefully unless market's block number equals current block number if (accrualBlockNumber != getBlockNumber()) { return (fail(Error.MARKET_NOT_FRESH, FailureInfo.ADD_RESERVES_FRESH_CHECK), actualAddAmount); } ///////////////////////// // EFFECTS & INTERACTIONS // (No safe failures beyond this point) /* * We call doTransferIn for the caller and the addAmount * Note: The slToken must handle variations between ERC-20 and ETH underlying. * On success, the slToken holds an additional addAmount of cash. * doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred. * it returns the amount actually transferred, in case of a fee. */ actualAddAmount = doTransferIn(msg.sender, addAmount); totalReservesNew = totalReserves + actualAddAmount; /* Revert on overflow */ require(totalReservesNew >= totalReserves, "add reserves unexpected overflow"); // Store reserves[n+1] = reserves[n] + actualAddAmount totalReserves = totalReservesNew; /* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */ emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew); /* Return (NO_ERROR, actualAddAmount) */ return (uint(Error.NO_ERROR), actualAddAmount); } /** * @notice Accrues interest and reduces reserves by transferring to admin * @param reduceAmount Amount of reduction to reserves * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function _reduceReserves(uint reduceAmount) external nonReentrant returns (uint) { uint error = accrueInterest(); if (error != uint(Error.NO_ERROR)) { // accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed. return fail(Error(error), FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED); } // _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to. return _reduceReservesFresh(reduceAmount); } /** * @notice Reduces reserves by transferring to admin * @dev Requires fresh interest accrual * @param reduceAmount Amount of reduction to reserves * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function _reduceReservesFresh(uint reduceAmount) internal returns (uint) { // totalReserves - reduceAmount uint totalReservesNew; // Check caller is admin if (msg.sender != admin) { return fail(Error.UNAUTHORIZED, FailureInfo.REDUCE_RESERVES_ADMIN_CHECK); } // We fail gracefully unless market's block number equals current block number if (accrualBlockNumber != getBlockNumber()) { return fail(Error.MARKET_NOT_FRESH, FailureInfo.REDUCE_RESERVES_FRESH_CHECK); } // Fail gracefully if protocol has insufficient underlying cash if (getCashPrior() < reduceAmount) { return fail(Error.TOKEN_INSUFFICIENT_CASH, FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE); } // Check reduceAmount ≤ reserves[n] (totalReserves) if (reduceAmount > totalReserves) { return fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION); } ///////////////////////// // EFFECTS & INTERACTIONS // (No safe failures beyond this point) totalReservesNew = totalReserves - reduceAmount; // We checked reduceAmount <= totalReserves above, so this should never revert. require(totalReservesNew <= totalReserves, "reduce reserves unexpected underflow"); // Store reserves[n+1] = reserves[n] - reduceAmount totalReserves = totalReservesNew; // doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred. doTransferOut(admin, reduceAmount); emit ReservesReduced(admin, reduceAmount, totalReservesNew); return uint(Error.NO_ERROR); } /** * @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh * @dev Admin function to accrue interest and update the interest rate model * @param newInterestRateModel the new interest rate model to use * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function _setInterestRateModel(InterestRateModel newInterestRateModel) public returns (uint) { uint error = accrueInterest(); if (error != uint(Error.NO_ERROR)) { // accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed return fail(Error(error), FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED); } // _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to. return _setInterestRateModelFresh(newInterestRateModel); } /** * @notice updates the interest rate model (*requires fresh interest accrual) * @dev Admin function to update the interest rate model * @param newInterestRateModel the new interest rate model to use * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function _setInterestRateModelFresh(InterestRateModel newInterestRateModel) internal returns (uint) { // Used to store old model for use in the event that is emitted on success InterestRateModel oldInterestRateModel; // Check caller is admin if (msg.sender != admin) { return fail(Error.UNAUTHORIZED, FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK); } // We fail gracefully unless market's block number equals current block number if (accrualBlockNumber != getBlockNumber()) { return fail(Error.MARKET_NOT_FRESH, FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK); } // Track the market's current interest rate model oldInterestRateModel = interestRateModel; // Ensure invoke newInterestRateModel.isInterestRateModel() returns true require(newInterestRateModel.isInterestRateModel(), "marker method returned false"); // Set the interest rate model to newInterestRateModel interestRateModel = newInterestRateModel; // Emit NewMarketInterestRateModel(oldInterestRateModel, newInterestRateModel) emit NewMarketInterestRateModel(oldInterestRateModel, newInterestRateModel); return uint(Error.NO_ERROR); } /*** Safe Token ***/ /** * @notice Gets balance of this contract in terms of the underlying * @dev This excludes the value of the current message, if any * @return The quantity of underlying owned by this contract */ function getCashPrior() internal view returns (uint); /** * @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee. * This may revert due to insufficient balance or insufficient allowance. */ function doTransferIn(address from, uint amount) internal returns (uint); /** * @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting. * If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract. * If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions. */ function doTransferOut(address payable to, uint amount) internal; /*** Reentrancy Guard ***/ /** * @dev Prevents a contract from calling itself, directly or indirectly. */ modifier nonReentrant() { require(_notEntered, "re-entered"); _notEntered = false; _; _notEntered = true; // get a gas-refund post-Istanbul } } // File: contracts/SLEther.sol pragma solidity ^0.5.16; /** * @title SashimiLending's SLEther Contract * @notice SLToken which wraps Ether * @author SashimiLending */ contract SLEther is SLToken { /** * @notice Construct a new SLEther money market * @param comptroller_ The address of the Comptroller * @param interestRateModel_ The address of the interest rate model * @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18 * @param name_ ERC-20 name of this token * @param symbol_ ERC-20 symbol of this token * @param decimals_ ERC-20 decimal precision of this token * @param admin_ Address of the administrator of this token */ constructor(ComptrollerInterface comptroller_, InterestRateModel interestRateModel_, uint initialExchangeRateMantissa_, string memory name_, string memory symbol_, uint8 decimals_, address payable admin_) public { // Creator of the contract is admin during initialization admin = msg.sender; initialize(comptroller_, interestRateModel_, initialExchangeRateMantissa_, name_, symbol_, decimals_); // Set the proper admin now that initialization is done admin = admin_; } /*** User Interface ***/ /** * @notice Sender supplies assets into the market and receives slTokens in exchange * @dev Reverts upon any failure */ function mint() external payable { (uint err,) = mintInternal(msg.value); requireNoError(err, "mint failed"); } /** * @notice Sender redeems slTokens in exchange for the underlying asset * @dev Accrues interest whether or not the operation succeeds, unless reverted * @param redeemTokens The number of slTokens to redeem into underlying * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function redeem(uint redeemTokens) external returns (uint) { return redeemInternal(redeemTokens); } /** * @notice Sender redeems slTokens in exchange for a specified amount of underlying asset * @dev Accrues interest whether or not the operation succeeds, unless reverted * @param redeemAmount The amount of underlying to redeem * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function redeemUnderlying(uint redeemAmount) external returns (uint) { return redeemUnderlyingInternal(redeemAmount); } /** * @notice Sender borrows assets from the protocol to their own address * @param borrowAmount The amount of the underlying asset to borrow * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details) */ function borrow(uint borrowAmount) external returns (uint) { return borrowInternal(borrowAmount); } /** * @notice Sender repays their own borrow * @dev Reverts upon any failure */ function repayBorrow() external payable { (uint err,) = repayBorrowInternal(msg.value); requireNoError(err, "repayBorrow failed"); } /** * @notice Sender repays a borrow belonging to borrower * @dev Reverts upon any failure * @param borrower the account with the debt being payed off */ function repayBorrowBehalf(address borrower) external payable { (uint err,) = repayBorrowBehalfInternal(borrower, msg.value); requireNoError(err, "repayBorrowBehalf failed"); } /** * @notice The sender liquidates the borrowers collateral. * The collateral seized is transferred to the liquidator. * @dev Reverts upon any failure * @param borrower The borrower of this slToken to be liquidated * @param slTokenCollateral The market in which to seize collateral from the borrower */ function liquidateBorrow(address borrower, SLToken slTokenCollateral) external payable { (uint err,) = liquidateBorrowInternal(borrower, msg.value, slTokenCollateral); requireNoError(err, "liquidateBorrow failed"); } /** * @notice Send Ether to SLEther to mint */ function () external payable { (uint err,) = mintInternal(msg.value); requireNoError(err, "mint failed"); } /*** Safe Token ***/ /** * @notice Gets balance of this contract in terms of Ether, before this message * @dev This excludes the value of the current message, if any * @return The quantity of Ether owned by this contract */ function getCashPrior() internal view returns (uint) { (MathError err, uint startingBalance) = subUInt(address(this).balance, msg.value); require(err == MathError.NO_ERROR); return startingBalance; } /** * @notice Perform the actual transfer in, which is a no-op * @param from Address sending the Ether * @param amount Amount of Ether being sent * @return The actual amount of Ether transferred */ function doTransferIn(address from, uint amount) internal returns (uint) { // Sanity checks require(msg.sender == from, "sender mismatch"); require(msg.value == amount, "value mismatch"); return amount; } function doTransferOut(address payable to, uint amount) internal { /* Send the Ether, with minimal gas and revert on failure */ to.transfer(amount); } function requireNoError(uint errCode, string memory message) internal pure { if (errCode == uint(Error.NO_ERROR)) { return; } bytes memory fullMessage = new bytes(bytes(message).length + 5); uint i; for (i = 0; i < bytes(message).length; i++) { fullMessage[i] = bytes(message)[i]; } fullMessage[i+0] = byte(uint8(32)); fullMessage[i+1] = byte(uint8(40)); fullMessage[i+2] = byte(uint8(48 + ( errCode / 10 ))); fullMessage[i+3] = byte(uint8(48 + ( errCode % 10 ))); fullMessage[i+4] = byte(uint8(41)); require(errCode == uint(Error.NO_ERROR), string(fullMessage)); } } // File: contracts/Maximillion.sol pragma solidity ^0.5.16; /** * @title Compound's Maximillion Contract * @author Compound */ contract Maximillion { /** * @notice The default slEther market to repay in */ SLEther public slEther; /** * @notice Construct a Maximillion to repay max in a SLEther market */ constructor(SLEther slEther_) public { slEther = slEther_; } /** * @notice msg.sender sends Ether to repay an account's borrow in the slEther market * @dev The provided Ether is applied towards the borrow balance, any excess is refunded * @param borrower The address of the borrower account to repay on behalf of */ function repayBehalf(address borrower) public payable { repayBehalfExplicit(borrower, slEther); } /** * @notice msg.sender sends Ether to repay an account's borrow in a slEther market * @dev The provided Ether is applied towards the borrow balance, any excess is refunded * @param borrower The address of the borrower account to repay on behalf of * @param slEther_ The address of the slEther contract to repay in */ function repayBehalfExplicit(address borrower, SLEther slEther_) public payable { uint received = msg.value; uint borrows = slEther_.borrowBalanceCurrent(borrower); if (received > borrows) { slEther_.repayBorrowBehalf.value(borrows)(borrower); msg.sender.transfer(received - borrows); } else { slEther_.repayBorrowBehalf.value(received)(borrower); } } }

abi

bytecode