Contract Source Code:
// SPDX-License-Identifier: BSD-3-Clause
pragma solidity 0.8.19;
/**
* @title Careful Math
* @author Moonwell
* @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);
}
}
// SPDX-License-Identifier: BSD-3-Clause
pragma solidity 0.8.19;
abstract 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 mTokens
) external virtual returns (uint[] memory);
function exitMarket(address mToken) external virtual returns (uint);
/*** Policy Hooks ***/
function mintAllowed(
address mToken,
address minter,
uint mintAmount
) external virtual returns (uint);
function redeemAllowed(
address mToken,
address redeemer,
uint redeemTokens
) external virtual returns (uint);
// Do not remove, still used by MToken
function redeemVerify(
address mToken,
address redeemer,
uint redeemAmount,
uint redeemTokens
) external pure virtual;
function borrowAllowed(
address mToken,
address borrower,
uint borrowAmount
) external virtual returns (uint);
function repayBorrowAllowed(
address mToken,
address payer,
address borrower,
uint repayAmount
) external virtual returns (uint);
function liquidateBorrowAllowed(
address mTokenBorrowed,
address mTokenCollateral,
address liquidator,
address borrower,
uint repayAmount
) external view virtual returns (uint);
function seizeAllowed(
address mTokenCollateral,
address mTokenBorrowed,
address liquidator,
address borrower,
uint seizeTokens
) external virtual returns (uint);
function transferAllowed(
address mToken,
address src,
address dst,
uint transferTokens
) external virtual returns (uint);
/*** Liquidity/Liquidation Calculations ***/
function liquidateCalculateSeizeTokens(
address mTokenBorrowed,
address mTokenCollateral,
uint repayAmount
) external view virtual returns (uint, uint);
}
// The hooks that were patched out of the comptroller to make room for the supply caps, if we need them
abstract contract ComptrollerInterfaceWithAllVerificationHooks is
ComptrollerInterface
{
function mintVerify(
address mToken,
address minter,
uint mintAmount,
uint mintTokens
) external virtual;
// Included in ComptrollerInterface already
// function redeemVerify(address mToken, address redeemer, uint redeemAmount, uint redeemTokens) virtual external;
function borrowVerify(
address mToken,
address borrower,
uint borrowAmount
) external virtual;
function repayBorrowVerify(
address mToken,
address payer,
address borrower,
uint repayAmount,
uint borrowerIndex
) external virtual;
function liquidateBorrowVerify(
address mTokenBorrowed,
address mTokenCollateral,
address liquidator,
address borrower,
uint repayAmount,
uint seizeTokens
) external virtual;
function seizeVerify(
address mTokenCollateral,
address mTokenBorrowed,
address liquidator,
address borrower,
uint seizeTokens
) external virtual;
function transferVerify(
address mToken,
address src,
address dst,
uint transferTokens
) external virtual;
}
// SPDX-License-Identifier: BSD-3-Clause
pragma solidity 0.8.19;
/**
* @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 balance 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 success 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 success 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 success 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 remaining 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
);
}
// SPDX-License-Identifier: BSD-3-Clause
pragma solidity 0.8.19;
/**
* @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 balance 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 success 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 remaining 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
);
}
// SPDX-License-Identifier: BSD-3-Clause
pragma solidity 0.8.19;
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,
SET_GAS_AMOUNT_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,
SET_PROTOCOL_SEIZE_SHARE_ACCRUE_INTEREST_FAILED,
SET_PROTOCOL_SEIZE_SHARE_OWNER_CHECK,
SET_PROTOCOL_SEIZE_SHARE_FRESH_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);
}
}
// SPDX-License-Identifier: BSD-3-Clause
pragma solidity 0.8.19;
import "./CarefulMath.sol";
import "./ExponentialNoError.sol";
/**
* @title Exponential module for storing fixed-precision decimals
* @author Moonwell
* @dev Legacy contract for compatibility reasons with existing contracts that still use MathError
* @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, ExponentialNoError {
/**
* @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
) internal pure 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
) internal pure 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
) internal pure 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
) internal pure 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
) internal pure 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
) internal pure 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
) internal pure 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
) internal pure 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
) internal pure 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
) internal pure 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
) internal pure 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
) internal pure 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
) internal pure returns (MathError, Exp memory) {
return getExp(a.mantissa, b.mantissa);
}
}
// SPDX-License-Identifier: BSD-3-Clause
pragma solidity 0.8.19;
/**
* @title Exponential module for storing fixed-precision decimals
* @author Moonwell
* @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 ExponentialNoError {
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 Truncates the given exp to a whole number value.
* For example, truncate(Exp{mantissa: 15 * expScale}) = 15
*/
function truncate(Exp memory exp) internal pure returns (uint) {
// Note: We are not using careful math here as we're performing a division that cannot fail
return exp.mantissa / expScale;
}
/**
* @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
*/
function mul_ScalarTruncate(
Exp memory a,
uint scalar
) internal pure returns (uint) {
Exp memory product = mul_(a, scalar);
return truncate(product);
}
/**
* @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
*/
function mul_ScalarTruncateAddUInt(
Exp memory a,
uint scalar,
uint addend
) internal pure returns (uint) {
Exp memory product = mul_(a, scalar);
return add_(truncate(product), addend);
}
/**
* @dev Checks if first Exp is less than second Exp.
*/
function lessThanExp(
Exp memory left,
Exp memory right
) internal pure returns (bool) {
return left.mantissa < right.mantissa;
}
/**
* @dev Checks if left Exp <= right Exp.
*/
function lessThanOrEqualExp(
Exp memory left,
Exp memory right
) internal pure returns (bool) {
return left.mantissa <= right.mantissa;
}
/**
* @dev Checks if left Exp > right Exp.
*/
function greaterThanExp(
Exp memory left,
Exp memory right
) internal pure returns (bool) {
return left.mantissa > right.mantissa;
}
/**
* @dev returns true if Exp is exactly zero
*/
function isZeroExp(Exp memory value) internal pure returns (bool) {
return value.mantissa == 0;
}
function safe224(
uint n,
string memory errorMessage
) internal pure returns (uint224) {
require(n < 2 ** 224, errorMessage);
return uint224(n);
}
function safe32(
uint n,
string memory errorMessage
) internal pure returns (uint32) {
require(n < 2 ** 32, errorMessage);
return uint32(n);
}
function add_(
Exp memory a,
Exp memory b
) internal pure returns (Exp memory) {
return Exp({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(
Double memory a,
Double memory b
) internal pure returns (Double memory) {
return Double({mantissa: add_(a.mantissa, b.mantissa)});
}
function add_(uint a, uint b) internal pure returns (uint) {
return add_(a, b, "addition overflow");
}
function add_(
uint a,
uint b,
string memory errorMessage
) internal pure returns (uint) {
uint c = a + b;
require(c >= a, errorMessage);
return c;
}
function sub_(
Exp memory a,
Exp memory b
) internal pure returns (Exp memory) {
return Exp({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(
Double memory a,
Double memory b
) internal pure returns (Double memory) {
return Double({mantissa: sub_(a.mantissa, b.mantissa)});
}
function sub_(uint a, uint b) internal pure returns (uint) {
return sub_(a, b, "subtraction underflow");
}
function sub_(
uint a,
uint b,
string memory errorMessage
) internal pure returns (uint) {
require(b <= a, errorMessage);
return a - b;
}
function mul_(
Exp memory a,
Exp memory b
) internal pure returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b.mantissa) / expScale});
}
function mul_(Exp memory a, uint b) internal pure returns (Exp memory) {
return Exp({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Exp memory b) internal pure returns (uint) {
return mul_(a, b.mantissa) / expScale;
}
function mul_(
Double memory a,
Double memory b
) internal pure returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b.mantissa) / doubleScale});
}
function mul_(
Double memory a,
uint b
) internal pure returns (Double memory) {
return Double({mantissa: mul_(a.mantissa, b)});
}
function mul_(uint a, Double memory b) internal pure returns (uint) {
return mul_(a, b.mantissa) / doubleScale;
}
function mul_(uint a, uint b) internal pure returns (uint) {
return mul_(a, b, "multiplication overflow");
}
function mul_(
uint a,
uint b,
string memory errorMessage
) internal pure 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
) internal pure returns (Exp memory) {
return Exp({mantissa: div_(mul_(a.mantissa, expScale), b.mantissa)});
}
function div_(Exp memory a, uint b) internal pure returns (Exp memory) {
return Exp({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Exp memory b) internal pure returns (uint) {
return div_(mul_(a, expScale), b.mantissa);
}
function div_(
Double memory a,
Double memory b
) internal pure returns (Double memory) {
return
Double({mantissa: div_(mul_(a.mantissa, doubleScale), b.mantissa)});
}
function div_(
Double memory a,
uint b
) internal pure returns (Double memory) {
return Double({mantissa: div_(a.mantissa, b)});
}
function div_(uint a, Double memory b) internal pure returns (uint) {
return div_(mul_(a, doubleScale), b.mantissa);
}
function div_(uint a, uint b) internal pure returns (uint) {
return div_(a, b, "divide by zero");
}
function div_(
uint a,
uint b,
string memory errorMessage
) internal pure returns (uint) {
require(b > 0, errorMessage);
return a / b;
}
function fraction(uint a, uint b) internal pure returns (Double memory) {
return Double({mantissa: div_(mul_(a, doubleScale), b)});
}
}
// SPDX-License-Identifier: BSD-3-Clause
pragma solidity 0.8.19;
/**
* @title Moonwell's InterestRateModel Interface
* @author Moonwell
*/
abstract 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 timestamp
* @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 timestamp (as a percentage, and scaled by 1e18)
*/
function getBorrowRate(
uint cash,
uint borrows,
uint reserves
) external view virtual returns (uint);
/**
* @notice Calculates the current supply interest rate per timestamp
* @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 timestamp (as a percentage, and scaled by 1e18)
*/
function getSupplyRate(
uint cash,
uint borrows,
uint reserves,
uint reserveFactorMantissa
) external view virtual returns (uint);
}
// SPDX-License-Identifier: BSD-3-Clause
pragma solidity 0.8.19;
import "./MToken.sol";
/**
* @title Compound's CEther Contract
* @notice MToken which wraps Ether
* @author Compound
*/
contract MEther is MToken {
address public underlying = address(0);
/**
* @notice Construct a new CEther 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_,
uint256 initialExchangeRateMantissa_,
string memory name_,
string memory symbol_,
uint8 decimals_,
address payable admin_
) {
// Creator of the contract is admin during initialization
admin = payable(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 cTokens in exchange
* @dev Reverts upon any failure
*/
function mint() external payable {
mintInternal(msg.value);
}
/**
* @notice Sender redeems cTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of cTokens to redeem into underlying
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function redeem(uint256 redeemTokens) external returns (Error) {
redeemInternal(redeemTokens);
return Error.NO_ERROR;
}
/**
* @notice Sender redeems cTokens 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(uint256 redeemAmount) external returns (Error) {
redeemUnderlyingInternal(redeemAmount);
return 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 borrow(uint256 borrowAmount) external returns (Error) {
borrowInternal(borrowAmount);
return Error.NO_ERROR;
}
/**
* @notice Sender repays their own borrow
* @dev Reverts upon any failure
*/
function repayBorrow() external payable {
repayBorrowInternal(msg.value);
}
/// @notice Indicator that this is a ETH Derivative
function isEthDerivative() public view virtual returns (bool) {
return true;
}
/**
* @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 {
repayBorrowBehalfInternal(borrower, msg.value);
}
/**
* @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 MToken to be liquidated
* @param rfTokenCollateral The market in which to seize collateral from the borrower
*/
function liquidateBorrow(address borrower, MToken rfTokenCollateral) external payable {
liquidateBorrowInternal(borrower, msg.value, rfTokenCollateral);
}
/**
* @notice The sender adds to reserves.
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _addReserves() external payable returns (uint256) {
return _addReservesInternal(msg.value);
}
/**
* @notice Send Ether to CEther to mint
*/
receive() external payable {
mintInternal(msg.value);
}
/**
* 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 override returns (uint256) {
return address(this).balance - msg.value;
}
/**
* @notice A public function to sweep accidental ERC-20 transfers to this contract. Tokens are sent to admin (timelock)
*/
// function sweepToken() external {
// require(msg.sender == admin, "MEther::sweepToken: only admin can sweep tokens");
// uint256 balance = address(this).balance;
// require(balance > 0, "No ether left to send");
// (bool sent,) = payable(admin).call{value: balance}("");
// require(sent, "Failed to send Ether");
// }
/**
* @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, uint256 amount) internal override returns (uint256) {
// Sanity checks
require(msg.sender == from, "sender mismatch");
require(msg.value == amount, "value mismatch");
return amount;
}
function doTransferOut(address payable to, uint256 amount) internal virtual override {
/* Send the Ether, with minimal gas and revert on failure */
to.transfer(amount);
}
}
// SPDX-License-Identifier: BSD-3-Clause
pragma solidity 0.8.19;
import "./ComptrollerInterface.sol";
import "./MTokenInterfaces.sol";
import "./ErrorReporter.sol";
import "./Exponential.sol";
import "./EIP20Interface.sol";
import "./InterestRateModel.sol";
/**
* @title Moonwell's MToken Contract
* @notice Abstract base for MTokens
* @author Moonwell
*/
abstract contract MToken is MTokenInterface, 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(
accrualBlockTimestamp == 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 timestamp and borrow index (block timestamp mocks depend on comptroller being set)
accrualBlockTimestamp = getBlockTimestamp();
borrowIndex = mantissaOne;
// Set the interest rate model (depends on block timestamp / 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 = type(uint).max;
} 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 != type(uint).max) {
transferAllowances[src][spender] = allowanceNew;
}
/* We emit a Transfer event */
emit Transfer(src, dst, tokens);
// unused function
// 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 override 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 override 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 (uint.max means infinite)
* @return Whether or not the approval succeeded
*/
function approve(
address spender,
uint256 amount
) external override 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 (uint.max means infinite)
*/
function allowance(
address owner,
address spender
) external view override 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 override 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 override 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 override returns (uint, uint, uint, uint) {
uint mTokenBalance = 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),
mTokenBalance,
borrowBalance,
exchangeRateMantissa
);
}
/**
* @dev Function to simply retrieve block timestamp
* This exists mainly for inheriting test contracts to stub this result.
*/
function getBlockTimestamp() internal view virtual returns (uint) {
return block.timestamp;
}
/**
* @notice Returns the current per-timestamp borrow interest rate for this mToken
* @return The borrow interest rate per timestamp, scaled by 1e18
*/
function borrowRatePerTimestamp() external view override returns (uint) {
return
interestRateModel.getBorrowRate(
getCashPrior(),
totalBorrows,
totalReserves
);
}
/**
* @notice Returns the current per-timestamp supply interest rate for this mToken
* @return The supply interest rate per timestamp, scaled by 1e18
*/
function supplyRatePerTimestamp() external view override 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
override
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 override 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 override 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 override nonReentrant returns (uint) {
require(
accrueInterest() == uint(Error.NO_ERROR),
"accrue interest failed"
);
return exchangeRateStored();
}
/**
* @notice Calculates the exchange rate from the underlying to the MToken
* @dev This function does not accrue interest before calculating the exchange rate
* @return Calculated exchange rate scaled by 1e18
*/
function exchangeRateStored() public view override 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 MToken
* @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
virtual
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 mToken in the underlying asset
* @return The quantity of underlying asset owned by this contract
*/
function getCash() external view override 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 virtual override returns (uint) {
/* Remember the initial block timestamp */
uint currentBlockTimestamp = getBlockTimestamp();
uint accrualBlockTimestampPrior = accrualBlockTimestamp;
/* Short-circuit accumulating 0 interest */
if (accrualBlockTimestampPrior == currentBlockTimestamp) {
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(
currentBlockTimestamp,
accrualBlockTimestampPrior
);
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 */
accrualBlockTimestamp = currentBlockTimestamp;
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 mTokens 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 mTokens 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 timestamp equals current block timestamp */
if (accrualBlockTimestamp != getBlockTimestamp()) {
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 mToken must handle variations between ERC-20 and GLMR 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 mToken holds an additional `actualMintAmount`
* of cash.
*/
vars.actualMintAmount = doTransferIn(minter, mintAmount);
/*
* We get the current exchange rate and calculate the number of mTokens 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 mTokens 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 */
// unused function
// comptroller.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);
return (uint(Error.NO_ERROR), vars.actualMintAmount);
}
/**
* @notice Sender redeems mTokens in exchange for the underlying asset
* @dev Accrues interest whether or not the operation succeeds, unless reverted
* @param redeemTokens The number of mTokens 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(payable(msg.sender), redeemTokens, 0);
}
/**
* @notice Sender redeems mTokens 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 mTokens
* @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(payable(msg.sender), 0, redeemAmount);
}
struct RedeemLocalVars {
Error err;
MathError mathErr;
uint exchangeRateMantissa;
uint redeemTokens;
uint redeemAmount;
uint totalSupplyNew;
uint accountTokensNew;
}
/**
* @notice User redeems mTokens 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 mTokens 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 mTokens (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
*/
if (redeemTokensIn == type(uint).max) {
vars.redeemTokens = accountTokens[redeemer];
} else {
vars.redeemTokens = redeemTokensIn;
}
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(
Exp({mantissa: vars.exchangeRateMantissa}),
vars.redeemTokens
);
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
*/
if (redeemAmountIn == type(uint).max) {
vars.redeemTokens = accountTokens[redeemer];
(vars.mathErr, vars.redeemAmount) = mulScalarTruncate(
Exp({mantissa: vars.exchangeRateMantissa}),
vars.redeemTokens
);
if (vars.mathErr != MathError.NO_ERROR) {
return
failOpaque(
Error.MATH_ERROR,
FailureInfo
.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED,
uint(vars.mathErr)
);
}
} else {
vars.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)
);
}
}
}
/* 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 timestamp equals current block timestamp */
if (accrualBlockTimestamp != getBlockTimestamp()) {
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 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
);
/*
* We invoke doTransferOut for the redeemer and the redeemAmount.
* Note: The mToken must handle variations between ERC-20 and GLMR underlying.
* On success, the mToken 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);
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(payable(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 timestamp equals current block timestamp */
if (accrualBlockTimestamp != getBlockTimestamp()) {
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 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 invoke doTransferOut for the borrower and the borrowAmount.
* Note: The mToken must handle variations between ERC-20 and GLMR underlying.
* On success, the mToken borrowAmount less of cash.
* doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
*/
doTransferOut(borrower, borrowAmount);
/* We call the defense hook */
// unused function
// 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 underlying 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 timestamp equals current block timestamp */
if (accrualBlockTimestamp != getBlockTimestamp()) {
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 == uint.max, repayAmount = accountBorrows */
if (repayAmount == type(uint).max) {
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 mToken must handle variations between ERC-20 and GLMR underlying.
* On success, the mToken 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 */
// unused function
// 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 mToken to be liquidated
* @param mTokenCollateral 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,
MTokenInterface mTokenCollateral
) 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 = mTokenCollateral.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,
mTokenCollateral
);
}
/**
* @notice The liquidator liquidates the borrowers collateral.
* The collateral seized is transferred to the liquidator.
* @param borrower The borrower of this mToken to be liquidated
* @param liquidator The address repaying the borrow and seizing collateral
* @param mTokenCollateral 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,
MTokenInterface mTokenCollateral
) internal returns (uint, uint) {
/* Fail if liquidate not allowed */
uint allowed = comptroller.liquidateBorrowAllowed(
address(this),
address(mTokenCollateral),
liquidator,
borrower,
repayAmount
);
if (allowed != 0) {
return (
failOpaque(
Error.COMPTROLLER_REJECTION,
FailureInfo.LIQUIDATE_COMPTROLLER_REJECTION,
allowed
),
0
);
}
/* Verify market's block timestamp equals current block timestamp */
if (accrualBlockTimestamp != getBlockTimestamp()) {
return (
fail(
Error.MARKET_NOT_FRESH,
FailureInfo.LIQUIDATE_FRESHNESS_CHECK
),
0
);
}
/* Verify mTokenCollateral market's block timestamp equals current block timestamp */
if (mTokenCollateral.accrualBlockTimestamp() != getBlockTimestamp()) {
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 = uint.max */
if (repayAmount == type(uint).max) {
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(mTokenCollateral),
actualRepayAmount
);
require(
amountSeizeError == uint(Error.NO_ERROR),
"LIQUIDATE_COMPTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED"
);
/* Revert if borrower collateral token balance < seizeTokens */
require(
mTokenCollateral.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(mTokenCollateral) == address(this)) {
seizeError = seizeInternal(
address(this),
liquidator,
borrower,
seizeTokens
);
} else {
seizeError = mTokenCollateral.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(mTokenCollateral),
seizeTokens
);
/* We call the defense hook */
// unused function
// comptroller.liquidateBorrowVerify(address(this), address(mTokenCollateral), 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 mToken during the process of liquidation.
* Its absolutely critical to use msg.sender as the borrowed mToken and not a parameter.
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of mTokens to seize
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function seize(
address liquidator,
address borrower,
uint seizeTokens
) external override nonReentrant returns (uint) {
return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
}
struct SeizeInternalLocalVars {
MathError mathErr;
uint borrowerTokensNew;
uint liquidatorTokensNew;
uint liquidatorSeizeTokens;
uint protocolSeizeTokens;
uint protocolSeizeAmount;
uint exchangeRateMantissa;
uint totalReservesNew;
uint totalSupplyNew;
}
/**
* @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 MToken.
* Its absolutely critical to use msg.sender as the seizer mToken and not a parameter.
* @param seizerToken The contract seizing the collateral (i.e. borrowed mToken)
* @param liquidator The account receiving seized collateral
* @param borrower The account having collateral seized
* @param seizeTokens The number of mTokens 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
);
}
SeizeInternalLocalVars memory vars;
/*
* We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
* borrowerTokensNew = accountTokens[borrower] - seizeTokens
* liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
*/
(vars.mathErr, vars.borrowerTokensNew) = subUInt(
accountTokens[borrower],
seizeTokens
);
if (vars.mathErr != MathError.NO_ERROR) {
return
failOpaque(
Error.MATH_ERROR,
FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED,
uint(vars.mathErr)
);
}
vars.protocolSeizeTokens = mul_(
seizeTokens,
Exp({mantissa: protocolSeizeShareMantissa})
);
vars.liquidatorSeizeTokens = sub_(
seizeTokens,
vars.protocolSeizeTokens
);
(
vars.mathErr,
vars.exchangeRateMantissa
) = exchangeRateStoredInternal();
require(vars.mathErr == MathError.NO_ERROR, "exchange rate math error");
vars.protocolSeizeAmount = mul_ScalarTruncate(
Exp({mantissa: vars.exchangeRateMantissa}),
vars.protocolSeizeTokens
);
vars.totalReservesNew = add_(totalReserves, vars.protocolSeizeAmount);
vars.totalSupplyNew = sub_(totalSupply, vars.protocolSeizeTokens);
(vars.mathErr, vars.liquidatorTokensNew) = addUInt(
accountTokens[liquidator],
vars.liquidatorSeizeTokens
);
if (vars.mathErr != MathError.NO_ERROR) {
return
failOpaque(
Error.MATH_ERROR,
FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED,
uint(vars.mathErr)
);
}
/////////////////////////
// EFFECTS & INTERACTIONS
// (No safe failures beyond this point)
/* We write the previously calculated values into storage */
totalReserves = vars.totalReservesNew;
totalSupply = vars.totalSupplyNew;
accountTokens[borrower] = vars.borrowerTokensNew;
accountTokens[liquidator] = vars.liquidatorTokensNew;
/* Emit a Transfer event */
emit Transfer(borrower, liquidator, vars.liquidatorSeizeTokens);
emit Transfer(borrower, address(this), vars.protocolSeizeTokens);
emit ReservesAdded(
address(this),
vars.protocolSeizeAmount,
vars.totalReservesNew
);
/* We call the defense hook */
// unused function
// 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 override 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 override 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 = payable(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 override 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 override 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 timestamp equals current block timestamp
if (accrualBlockTimestamp != getBlockTimestamp()) {
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 timestamp equals current block timestamp
if (accrualBlockTimestamp != getBlockTimestamp()) {
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 mToken must handle variations between ERC-20 and GLMR underlying.
* On success, the mToken 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 override 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 timestamp equals current block timestamp
if (accrualBlockTimestamp != getBlockTimestamp()) {
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 override 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 timestamp equals current block timestamp
if (accrualBlockTimestamp != getBlockTimestamp()) {
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);
}
/**
* @notice accrues interest and updates the protocol seize share using _setProtocolSeizeShareFresh
* @dev Admin function to accrue interest and update the protocol seize share
* @param newProtocolSeizeShareMantissa the new protocol seize share to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setProtocolSeizeShare(
uint newProtocolSeizeShareMantissa
) external override 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 change of protocol seize share failed
return
fail(
Error(error),
FailureInfo.SET_PROTOCOL_SEIZE_SHARE_ACCRUE_INTEREST_FAILED
);
}
// _setProtocolSeizeShareFresh emits protocol-seize-share-update-specific logs on errors, so we don't need to.
return _setProtocolSeizeShareFresh(newProtocolSeizeShareMantissa);
}
/**
* @notice updates the protocol seize share (*requires fresh interest accrual)
* @dev Admin function to update the protocol seize share
* @param newProtocolSeizeShareMantissa the new protocol seize share to use
* @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
*/
function _setProtocolSeizeShareFresh(
uint newProtocolSeizeShareMantissa
) internal returns (uint) {
// Used to store old share for use in the event that is emitted on success
uint oldProtocolSeizeShareMantissa;
// Check caller is admin
if (msg.sender != admin) {
return
fail(
Error.UNAUTHORIZED,
FailureInfo.SET_PROTOCOL_SEIZE_SHARE_OWNER_CHECK
);
}
// We fail gracefully unless market's block timestamp equals current block timestamp
if (accrualBlockTimestamp != getBlockTimestamp()) {
return
fail(
Error.MARKET_NOT_FRESH,
FailureInfo.SET_PROTOCOL_SEIZE_SHARE_FRESH_CHECK
);
}
// Track the market's current protocol seize share
oldProtocolSeizeShareMantissa = protocolSeizeShareMantissa;
// Set the protocol seize share to newProtocolSeizeShareMantissa
protocolSeizeShareMantissa = newProtocolSeizeShareMantissa;
// Emit NewProtocolSeizeShareMantissa(oldProtocolSeizeShareMantissa, newProtocolSeizeShareMantissa)
emit NewProtocolSeizeShare(
oldProtocolSeizeShareMantissa,
newProtocolSeizeShareMantissa
);
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 virtual 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 virtual 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 virtual;
/*** 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
}
}
// SPDX-License-Identifier: BSD-3-Clause
pragma solidity 0.8.19;
import "./ComptrollerInterface.sol";
import "./InterestRateModel.sol";
import "./EIP20NonStandardInterface.sol";
import "./ErrorReporter.sol";
contract MTokenStorage {
/// @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-mToken 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 MTokens (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 accrualBlockTimestamp;
/// @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;
/// @notice Share of seized collateral that is added to reserves
uint public protocolSeizeShareMantissa;
}
abstract contract MTokenInterface is MTokenStorage {
/// @notice Indicator that this is a MToken contract (for inspection)
bool public constant isMToken = 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 mTokenCollateral,
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 protocol seize share is changed
event NewProtocolSeizeShare(
uint oldProtocolSeizeShareMantissa,
uint newProtocolSeizeShareMantissa
);
/// @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);
/*** User Interface ***/
function transfer(address dst, uint amount) external virtual returns (bool);
function transferFrom(
address src,
address dst,
uint amount
) external virtual returns (bool);
function approve(
address spender,
uint amount
) external virtual returns (bool);
function allowance(
address owner,
address spender
) external view virtual returns (uint);
function balanceOf(address owner) external view virtual returns (uint);
function balanceOfUnderlying(address owner) external virtual returns (uint);
function getAccountSnapshot(
address account
) external view virtual returns (uint, uint, uint, uint);
function borrowRatePerTimestamp() external view virtual returns (uint);
function supplyRatePerTimestamp() external view virtual returns (uint);
function totalBorrowsCurrent() external virtual returns (uint);
function borrowBalanceCurrent(
address account
) external virtual returns (uint);
function borrowBalanceStored(
address account
) external view virtual returns (uint);
function exchangeRateCurrent() external virtual returns (uint);
function exchangeRateStored() external view virtual returns (uint);
function getCash() external view virtual returns (uint);
function accrueInterest() external virtual returns (uint);
function seize(
address liquidator,
address borrower,
uint seizeTokens
) external virtual returns (uint);
/*** Admin Functions ***/
function _setPendingAdmin(
address payable newPendingAdmin
) external virtual returns (uint);
function _acceptAdmin() external virtual returns (uint);
function _setComptroller(
ComptrollerInterface newComptroller
) external virtual returns (uint);
function _setReserveFactor(
uint newReserveFactorMantissa
) external virtual returns (uint);
function _reduceReserves(uint reduceAmount) external virtual returns (uint);
function _setInterestRateModel(
InterestRateModel newInterestRateModel
) external virtual returns (uint);
function _setProtocolSeizeShare(
uint newProtocolSeizeShareMantissa
) external virtual returns (uint);
}
contract MErc20Storage {
/// @notice Underlying asset for this MToken
address public underlying;
}
abstract contract MErc20Interface is MErc20Storage {
/*** User Interface ***/
function mint(uint mintAmount) external virtual returns (uint);
function mintWithPermit(
uint mintAmount,
uint deadline,
uint8 v,
bytes32 r,
bytes32 s
) external virtual returns (uint);
function redeem(uint redeemTokens) external virtual returns (uint);
function redeemUnderlying(
uint redeemAmount
) external virtual returns (uint);
function borrow(uint borrowAmount) external virtual returns (uint);
function repayBorrow(uint repayAmount) external virtual returns (uint);
function repayBorrowBehalf(
address borrower,
uint repayAmount
) external virtual returns (uint);
function liquidateBorrow(
address borrower,
uint repayAmount,
MTokenInterface mTokenCollateral
) external virtual returns (uint);
function sweepToken(EIP20NonStandardInterface token) external virtual;
/*** Admin Functions ***/
function _addReserves(uint addAmount) external virtual returns (uint);
}
contract MDelegationStorage {
/// @notice Implementation address for this contract
address public implementation;
}
abstract contract MDelegatorInterface is MDelegationStorage {
/// @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
) external virtual;
}
abstract contract MDelegateInterface is MDelegationStorage {
/**
* @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) external virtual;
/// @notice Called by the delegator on a delegate to forfeit its responsibility
function _resignImplementation() external virtual;
}