Contract Source Code:
File 1 of 1 : AToken
pragma solidity ^0.5.0;
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a, "SafeMath: subtraction overflow");
uint256 c = a - b;
return c;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// Solidity only automatically asserts when dividing by 0
require(b > 0, "SafeMath: division by zero");
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b != 0, "SafeMath: modulo by zero");
return a % b;
}
}
/**
* @title WadRayMath library
* @author Aave
* @dev Provides mul and div function for wads (decimal numbers with 18 digits precision) and rays (decimals with 27 digits)
**/
library WadRayMath {
using SafeMath for uint256;
uint256 internal constant WAD = 1e18;
uint256 internal constant halfWAD = WAD / 2;
uint256 internal constant RAY = 1e27;
uint256 internal constant halfRAY = RAY / 2;
uint256 internal constant WAD_RAY_RATIO = 1e9;
/**
* @return one ray, 1e27
**/
function ray() internal pure returns (uint256) {
return RAY;
}
/**
* @return one wad, 1e18
**/
function wad() internal pure returns (uint256) {
return WAD;
}
/**
* @return half ray, 1e27/2
**/
function halfRay() internal pure returns (uint256) {
return halfRAY;
}
/**
* @return half ray, 1e18/2
**/
function halfWad() internal pure returns (uint256) {
return halfWAD;
}
/**
* @dev multiplies two wad, rounding half up to the nearest wad
* @param a wad
* @param b wad
* @return the result of a*b, in wad
**/
function wadMul(uint256 a, uint256 b) internal pure returns (uint256) {
return halfWAD.add(a.mul(b)).div(WAD);
}
/**
* @dev divides two wad, rounding half up to the nearest wad
* @param a wad
* @param b wad
* @return the result of a/b, in wad
**/
function wadDiv(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 halfB = b / 2;
return halfB.add(a.mul(WAD)).div(b);
}
/**
* @dev multiplies two ray, rounding half up to the nearest ray
* @param a ray
* @param b ray
* @return the result of a*b, in ray
**/
function rayMul(uint256 a, uint256 b) internal pure returns (uint256) {
return halfRAY.add(a.mul(b)).div(RAY);
}
/**
* @dev divides two ray, rounding half up to the nearest ray
* @param a ray
* @param b ray
* @return the result of a/b, in ray
**/
function rayDiv(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 halfB = b / 2;
return halfB.add(a.mul(RAY)).div(b);
}
/**
* @dev casts ray down to wad
* @param a ray
* @return a casted to wad, rounded half up to the nearest wad
**/
function rayToWad(uint256 a) internal pure returns (uint256) {
uint256 halfRatio = WAD_RAY_RATIO / 2;
return halfRatio.add(a).div(WAD_RAY_RATIO);
}
/**
* @dev convert wad up to ray
* @param a wad
* @return a converted in ray
**/
function wadToRay(uint256 a) internal pure returns (uint256) {
return a.mul(WAD_RAY_RATIO);
}
/**
* @dev calculates base^exp. The code uses the ModExp precompile
* @return base^exp, in ray
*/
//solium-disable-next-line
function rayPow(uint256 x, uint256 n) internal pure returns (uint256 z) {
z = n % 2 != 0 ? x : RAY;
for (n /= 2; n != 0; n /= 2) {
x = rayMul(x, x);
if (n % 2 != 0) {
z = rayMul(z, x);
}
}
}
}
/**
* @dev Contract module that helps prevent reentrant calls to a function.
*
* Inheriting from `ReentrancyGuard` will make the `nonReentrant` modifier
* available, which can be aplied to functions to make sure there are no nested
* (reentrant) calls to them.
*
* Note that because there is a single `nonReentrant` guard, functions marked as
* `nonReentrant` may not call one another. This can be worked around by making
* those functions `private`, and then adding `external` `nonReentrant` entry
* points to them.
*/
contract ReentrancyGuard {
/// @dev counter to allow mutex lock with only one SSTORE operation
uint256 private _guardCounter;
constructor () internal {
// The counter starts at one to prevent changing it from zero to a non-zero
// value, which is a more expensive operation.
_guardCounter = 1;
}
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* Calling a `nonReentrant` function from another `nonReentrant`
* function is not supported. It is possible to prevent this from happening
* by making the `nonReentrant` function external, and make it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
_guardCounter += 1;
uint256 localCounter = _guardCounter;
_;
require(localCounter == _guardCounter, "ReentrancyGuard: reentrant call");
}
}
/**
* @dev Collection of functions related to the address type,
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* This test is non-exhaustive, and there may be false-negatives: during the
* execution of a contract's constructor, its address will be reported as
* not containing a contract.
*
* > It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*/
function isContract(address account) internal view returns (bool) {
// This method relies in extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
// solhint-disable-next-line no-inline-assembly
assembly { size := extcodesize(account) }
return size > 0;
}
}
/**
* @dev Interface of the ERC20 standard as defined in the EIP. Does not include
* the optional functions; to access them see `ERC20Detailed`.
*/
interface IERC20 {
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a `Transfer` event.
*/
function transfer(address recipient, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through `transferFrom`. This is
* zero by default.
*
* This value changes when `approve` or `transferFrom` are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* > Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an `Approval` event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `sender` to `recipient` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a `Transfer` event.
*/
function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to `approve`. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
}
/**
* @dev Implementation of the `IERC20` interface.
*
* This implementation is agnostic to the way tokens are created. This means
* that a supply mechanism has to be added in a derived contract using `_mint`.
* For a generic mechanism see `ERC20Mintable`.
*
* *For a detailed writeup see our guide [How to implement supply
* mechanisms](https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226).*
*
* We have followed general OpenZeppelin guidelines: functions revert instead
* of returning `false` on failure. This behavior is nonetheless conventional
* and does not conflict with the expectations of ERC20 applications.
*
* Additionally, an `Approval` event is emitted on calls to `transferFrom`.
* This allows applications to reconstruct the allowance for all accounts just
* by listening to said events. Other implementations of the EIP may not emit
* these events, as it isn't required by the specification.
*
* Finally, the non-standard `decreaseAllowance` and `increaseAllowance`
* functions have been added to mitigate the well-known issues around setting
* allowances. See `IERC20.approve`.
*/
contract ERC20 is IERC20 {
using SafeMath for uint256;
mapping (address => uint256) private _balances;
mapping (address => mapping (address => uint256)) private _allowances;
uint256 private _totalSupply;
/**
* @dev See `IERC20.totalSupply`.
*/
function totalSupply() public view returns (uint256) {
return _totalSupply;
}
/**
* @dev See `IERC20.balanceOf`.
*/
function balanceOf(address account) public view returns (uint256) {
return _balances[account];
}
/**
* @dev See `IERC20.transfer`.
*
* Requirements:
*
* - `recipient` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/
function transfer(address recipient, uint256 amount) public returns (bool) {
_transfer(msg.sender, recipient, amount);
return true;
}
/**
* @dev See `IERC20.allowance`.
*/
function allowance(address owner, address spender) public view returns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See `IERC20.approve`.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 value) public returns (bool) {
_approve(msg.sender, spender, value);
return true;
}
/**
* @dev See `IERC20.transferFrom`.
*
* Emits an `Approval` event indicating the updated allowance. This is not
* required by the EIP. See the note at the beginning of `ERC20`;
*
* Requirements:
* - `sender` and `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `value`.
* - the caller must have allowance for `sender`'s tokens of at least
* `amount`.
*/
function transferFrom(address sender, address recipient, uint256 amount) public returns (bool) {
_transfer(sender, recipient, amount);
_approve(sender, msg.sender, _allowances[sender][msg.sender].sub(amount));
return true;
}
/**
* @dev Atomically increases the allowance granted to `spender` by the caller.
*
* This is an alternative to `approve` that can be used as a mitigation for
* problems described in `IERC20.approve`.
*
* Emits an `Approval` event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
_approve(msg.sender, spender, _allowances[msg.sender][spender].add(addedValue));
return true;
}
/**
* @dev Atomically decreases the allowance granted to `spender` by the caller.
*
* This is an alternative to `approve` that can be used as a mitigation for
* problems described in `IERC20.approve`.
*
* Emits an `Approval` event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `spender` must have allowance for the caller of at least
* `subtractedValue`.
*/
function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
_approve(msg.sender, spender, _allowances[msg.sender][spender].sub(subtractedValue));
return true;
}
/**
* @dev Moves tokens `amount` from `sender` to `recipient`.
*
* This is internal function is equivalent to `transfer`, and can be used to
* e.g. implement automatic token fees, slashing mechanisms, etc.
*
* Emits a `Transfer` event.
*
* Requirements:
*
* - `sender` cannot be the zero address.
* - `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `amount`.
*/
function _transfer(address sender, address recipient, uint256 amount) internal {
require(sender != address(0), "ERC20: transfer from the zero address");
require(recipient != address(0), "ERC20: transfer to the zero address");
_balances[sender] = _balances[sender].sub(amount);
_balances[recipient] = _balances[recipient].add(amount);
emit Transfer(sender, recipient, amount);
}
/** @dev Creates `amount` tokens and assigns them to `account`, increasing
* the total supply.
*
* Emits a `Transfer` event with `from` set to the zero address.
*
* Requirements
*
* - `to` cannot be the zero address.
*/
function _mint(address account, uint256 amount) internal {
require(account != address(0), "ERC20: mint to the zero address");
_totalSupply = _totalSupply.add(amount);
_balances[account] = _balances[account].add(amount);
emit Transfer(address(0), account, amount);
}
/**
* @dev Destoys `amount` tokens from `account`, reducing the
* total supply.
*
* Emits a `Transfer` event with `to` set to the zero address.
*
* Requirements
*
* - `account` cannot be the zero address.
* - `account` must have at least `amount` tokens.
*/
function _burn(address account, uint256 value) internal {
require(account != address(0), "ERC20: burn from the zero address");
_totalSupply = _totalSupply.sub(value);
_balances[account] = _balances[account].sub(value);
emit Transfer(account, address(0), value);
}
/**
* @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
*
* This is internal function is equivalent to `approve`, and can be used to
* e.g. set automatic allowances for certain subsystems, etc.
*
* Emits an `Approval` event.
*
* Requirements:
*
* - `owner` cannot be the zero address.
* - `spender` cannot be the zero address.
*/
function _approve(address owner, address spender, uint256 value) internal {
require(owner != address(0), "ERC20: approve from the zero address");
require(spender != address(0), "ERC20: approve to the zero address");
_allowances[owner][spender] = value;
emit Approval(owner, spender, value);
}
/**
* @dev Destoys `amount` tokens from `account`.`amount` is then deducted
* from the caller's allowance.
*
* See `_burn` and `_approve`.
*/
function _burnFrom(address account, uint256 amount) internal {
_burn(account, amount);
_approve(account, msg.sender, _allowances[account][msg.sender].sub(amount));
}
}
/**
* @dev Optional functions from the ERC20 standard.
*/
contract ERC20Detailed is IERC20 {
string private _name;
string private _symbol;
uint8 private _decimals;
/**
* @dev Sets the values for `name`, `symbol`, and `decimals`. All three of
* these values are immutable: they can only be set once during
* construction.
*/
constructor (string memory name, string memory symbol, uint8 decimals) public {
_name = name;
_symbol = symbol;
_decimals = decimals;
}
/**
* @dev Returns the name of the token.
*/
function name() public view returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view returns (string memory) {
return _symbol;
}
/**
* @dev Returns the number of decimals used to get its user representation.
* For example, if `decimals` equals `2`, a balance of `505` tokens should
* be displayed to a user as `5,05` (`505 / 10 ** 2`).
*
* Tokens usually opt for a value of 18, imitating the relationship between
* Ether and Wei.
*
* > Note that this information is only used for _display_ purposes: it in
* no way affects any of the arithmetic of the contract, including
* `IERC20.balanceOf` and `IERC20.transfer`.
*/
function decimals() public view returns (uint8) {
return _decimals;
}
}
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* To use this library you can add a `using SafeERC20 for ERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20 {
using SafeMath for uint256;
using Address for address;
function safeTransfer(IERC20 token, address to, uint256 value) internal {
callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
function safeApprove(IERC20 token, address spender, uint256 value) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
// solhint-disable-next-line max-line-length
require((value == 0) || (token.allowance(address(this), spender) == 0),
"SafeERC20: approve from non-zero to non-zero allowance"
);
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender).add(value);
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender).sub(value);
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves.
// A Solidity high level call has three parts:
// 1. The target address is checked to verify it contains contract code
// 2. The call itself is made, and success asserted
// 3. The return value is decoded, which in turn checks the size of the returned data.
// solhint-disable-next-line max-line-length
require(address(token).isContract(), "SafeERC20: call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = address(token).call(data);
require(success, "SafeERC20: low-level call failed");
if (returndata.length > 0) { // Return data is optional
// solhint-disable-next-line max-line-length
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
/**
* @title VersionedInitializable
*
* @dev Helper contract to support initializer functions. To use it, replace
* the constructor with a function that has the `initializer` modifier.
* WARNING: Unlike constructors, initializer functions must be manually
* invoked. This applies both to deploying an Initializable contract, as well
* as extending an Initializable contract via inheritance.
* WARNING: When used with inheritance, manual care must be taken to not invoke
* a parent initializer twice, or ensure that all initializers are idempotent,
* because this is not dealt with automatically as with constructors.
*
* @author Aave, inspired by the OpenZeppelin Initializable contract
*/
contract VersionedInitializable {
/**
* @dev Indicates that the contract has been initialized.
*/
uint256 private lastInitializedRevision = 0;
/**
* @dev Indicates that the contract is in the process of being initialized.
*/
bool private initializing;
/**
* @dev Modifier to use in the initializer function of a contract.
*/
modifier initializer() {
uint256 revision = getRevision();
require(initializing || isConstructor() || revision > lastInitializedRevision, "Contract instance has already been initialized");
bool isTopLevelCall = !initializing;
if (isTopLevelCall) {
initializing = true;
lastInitializedRevision = revision;
}
_;
if (isTopLevelCall) {
initializing = false;
}
}
/// @dev returns the revision number of the contract.
/// Needs to be defined in the inherited class as a constant.
function getRevision() internal pure returns(uint256);
/// @dev Returns true if and only if the function is running in the constructor
function isConstructor() private view returns (bool) {
// extcodesize checks the size of the code stored in an address, and
// address returns the current address. Since the code is still not
// deployed when running a constructor, any checks on its code size will
// yield zero, making it an effective way to detect if a contract is
// under construction or not.
uint256 cs;
//solium-disable-next-line
assembly {
cs := extcodesize(address)
}
return cs == 0;
}
// Reserved storage space to allow for layout changes in the future.
uint256[50] private ______gap;
}
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be aplied to your functions to restrict their use to
* the owner.
*/
contract Ownable {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor () internal {
_owner = msg.sender;
emit OwnershipTransferred(address(0), _owner);
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(isOwner(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Returns true if the caller is the current owner.
*/
function isOwner() public view returns (bool) {
return msg.sender == _owner;
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* > Note: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public onlyOwner {
emit OwnershipTransferred(_owner, address(0));
_owner = address(0);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public onlyOwner {
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
*/
function _transferOwnership(address newOwner) internal {
require(newOwner != address(0), "Ownable: new owner is the zero address");
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
/**
* @title Proxy
* @dev Implements delegation of calls to other contracts, with proper
* forwarding of return values and bubbling of failures.
* It defines a fallback function that delegates all calls to the address
* returned by the abstract _implementation() internal function.
*/
contract Proxy {
/**
* @dev Fallback function.
* Implemented entirely in `_fallback`.
*/
function() external payable {
_fallback();
}
/**
* @return The Address of the implementation.
*/
function _implementation() internal view returns (address);
/**
* @dev Delegates execution to an implementation contract.
* This is a low level function that doesn't return to its internal call site.
* It will return to the external caller whatever the implementation returns.
* @param implementation Address to delegate.
*/
function _delegate(address implementation) internal {
//solium-disable-next-line
assembly {
// Copy msg.data. We take full control of memory in this inline assembly
// block because it will not return to Solidity code. We overwrite the
// Solidity scratch pad at memory position 0.
calldatacopy(0, 0, calldatasize)
// Call the implementation.
// out and outsize are 0 because we don't know the size yet.
let result := delegatecall(gas, implementation, 0, calldatasize, 0, 0)
// Copy the returned data.
returndatacopy(0, 0, returndatasize)
switch result
// delegatecall returns 0 on error.
case 0 {
revert(0, returndatasize)
}
default {
return(0, returndatasize)
}
}
}
/**
* @dev Function that is run as the first thing in the fallback function.
* Can be redefined in derived contracts to add functionality.
* Redefinitions must call super._willFallback().
*/
function _willFallback() internal {}
/**
* @dev fallback implementation.
* Extracted to enable manual triggering.
*/
function _fallback() internal {
_willFallback();
_delegate(_implementation());
}
}
/**
* @title BaseUpgradeabilityProxy
* @dev This contract implements a proxy that allows to change the
* implementation address to which it will delegate.
* Such a change is called an implementation upgrade.
*/
contract BaseUpgradeabilityProxy is Proxy {
/**
* @dev Emitted when the implementation is upgraded.
* @param implementation Address of the new implementation.
*/
event Upgraded(address indexed implementation);
/**
* @dev Storage slot with the address of the current implementation.
* This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
* validated in the constructor.
*/
bytes32 internal constant IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
/**
* @dev Returns the current implementation.
* @return Address of the current implementation
*/
function _implementation() internal view returns (address impl) {
bytes32 slot = IMPLEMENTATION_SLOT;
//solium-disable-next-line
assembly {
impl := sload(slot)
}
}
/**
* @dev Upgrades the proxy to a new implementation.
* @param newImplementation Address of the new implementation.
*/
function _upgradeTo(address newImplementation) internal {
_setImplementation(newImplementation);
emit Upgraded(newImplementation);
}
/**
* @dev Sets the implementation address of the proxy.
* @param newImplementation Address of the new implementation.
*/
function _setImplementation(address newImplementation) internal {
require(
Address.isContract(newImplementation),
"Cannot set a proxy implementation to a non-contract address"
);
bytes32 slot = IMPLEMENTATION_SLOT;
//solium-disable-next-line
assembly {
sstore(slot, newImplementation)
}
}
}
/**
* @title BaseAdminUpgradeabilityProxy
* @dev This contract combines an upgradeability proxy with an authorization
* mechanism for administrative tasks.
* All external functions in this contract must be guarded by the
* `ifAdmin` modifier. See ethereum/solidity#3864 for a Solidity
* feature proposal that would enable this to be done automatically.
*/
contract BaseAdminUpgradeabilityProxy is BaseUpgradeabilityProxy {
/**
* @dev Emitted when the administration has been transferred.
* @param previousAdmin Address of the previous admin.
* @param newAdmin Address of the new admin.
*/
event AdminChanged(address previousAdmin, address newAdmin);
/**
* @dev Storage slot with the admin of the contract.
* This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
* validated in the constructor.
*/
bytes32 internal constant ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
/**
* @dev Modifier to check whether the `msg.sender` is the admin.
* If it is, it will run the function. Otherwise, it will delegate the call
* to the implementation.
*/
modifier ifAdmin() {
if (msg.sender == _admin()) {
_;
} else {
_fallback();
}
}
/**
* @return The address of the proxy admin.
*/
function admin() external ifAdmin returns (address) {
return _admin();
}
/**
* @return The address of the implementation.
*/
function implementation() external ifAdmin returns (address) {
return _implementation();
}
/**
* @dev Changes the admin of the proxy.
* Only the current admin can call this function.
* @param newAdmin Address to transfer proxy administration to.
*/
function changeAdmin(address newAdmin) external ifAdmin {
require(newAdmin != address(0), "Cannot change the admin of a proxy to the zero address");
emit AdminChanged(_admin(), newAdmin);
_setAdmin(newAdmin);
}
/**
* @dev Upgrade the backing implementation of the proxy.
* Only the admin can call this function.
* @param newImplementation Address of the new implementation.
*/
function upgradeTo(address newImplementation) external ifAdmin {
_upgradeTo(newImplementation);
}
/**
* @dev Upgrade the backing implementation of the proxy and call a function
* on the new implementation.
* This is useful to initialize the proxied contract.
* @param newImplementation Address of the new implementation.
* @param data Data to send as msg.data in the low level call.
* It should include the signature and the parameters of the function to be called, as described in
* https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector-and-argument-encoding.
*/
function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
_upgradeTo(newImplementation);
(bool success, ) = newImplementation.delegatecall(data);
require(success);
}
/**
* @return The admin slot.
*/
function _admin() internal view returns (address adm) {
bytes32 slot = ADMIN_SLOT;
//solium-disable-next-line
assembly {
adm := sload(slot)
}
}
/**
* @dev Sets the address of the proxy admin.
* @param newAdmin Address of the new proxy admin.
*/
function _setAdmin(address newAdmin) internal {
bytes32 slot = ADMIN_SLOT;
//solium-disable-next-line
assembly {
sstore(slot, newAdmin)
}
}
/**
* @dev Only fall back when the sender is not the admin.
*/
function _willFallback() internal {
require(msg.sender != _admin(), "Cannot call fallback function from the proxy admin");
super._willFallback();
}
}
/**
* @title UpgradeabilityProxy
* @dev Extends BaseUpgradeabilityProxy with a constructor for initializing
* implementation and init data.
*/
contract UpgradeabilityProxy is BaseUpgradeabilityProxy {
/**
* @dev Contract constructor.
* @param _logic Address of the initial implementation.
* @param _data Data to send as msg.data to the implementation to initialize the proxied contract.
* It should include the signature and the parameters of the function to be called, as described in
* https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector-and-argument-encoding.
* This parameter is optional, if no data is given the initialization call to proxied contract will be skipped.
*/
constructor(address _logic, bytes memory _data) public payable {
assert(IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
_setImplementation(_logic);
if (_data.length > 0) {
(bool success, ) = _logic.delegatecall(_data);
require(success);
}
}
}
/**
* @title AdminUpgradeabilityProxy
* @dev Extends from BaseAdminUpgradeabilityProxy with a constructor for
* initializing the implementation, admin, and init data.
*/
contract AdminUpgradeabilityProxy is BaseAdminUpgradeabilityProxy, UpgradeabilityProxy {
/**
* Contract constructor.
* @param _logic address of the initial implementation.
* @param _admin Address of the proxy administrator.
* @param _data Data to send as msg.data to the implementation to initialize the proxied contract.
* It should include the signature and the parameters of the function to be called, as described in
* https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector-and-argument-encoding.
* This parameter is optional, if no data is given the initialization call to proxied contract will be skipped.
*/
constructor(address _logic, address _admin, bytes memory _data) public payable UpgradeabilityProxy(_logic, _data) {
assert(ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
_setAdmin(_admin);
}
}
/**
* @title InitializableUpgradeabilityProxy
* @dev Extends BaseUpgradeabilityProxy with an initializer for initializing
* implementation and init data.
*/
contract InitializableUpgradeabilityProxy is BaseUpgradeabilityProxy {
/**
* @dev Contract initializer.
* @param _logic Address of the initial implementation.
* @param _data Data to send as msg.data to the implementation to initialize the proxied contract.
* It should include the signature and the parameters of the function to be called, as described in
* https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector-and-argument-encoding.
* This parameter is optional, if no data is given the initialization call to proxied contract will be skipped.
*/
function initialize(address _logic, bytes memory _data) public payable {
require(_implementation() == address(0));
assert(IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
_setImplementation(_logic);
if (_data.length > 0) {
(bool success, ) = _logic.delegatecall(_data);
require(success);
}
}
}
contract AddressStorage {
mapping(bytes32 => address) private addresses;
function getAddress(bytes32 _key) public view returns (address) {
return addresses[_key];
}
function _setAddress(bytes32 _key, address _value) internal {
addresses[_key] = _value;
}
}
/**
* @title InitializableAdminUpgradeabilityProxy
* @dev Extends from BaseAdminUpgradeabilityProxy with an initializer for
* initializing the implementation, admin, and init data.
*/
contract InitializableAdminUpgradeabilityProxy is BaseAdminUpgradeabilityProxy, InitializableUpgradeabilityProxy {
/**
* Contract initializer.
* @param _logic address of the initial implementation.
* @param _admin Address of the proxy administrator.
* @param _data Data to send as msg.data to the implementation to initialize the proxied contract.
* It should include the signature and the parameters of the function to be called, as described in
* https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector-and-argument-encoding.
* This parameter is optional, if no data is given the initialization call to proxied contract will be skipped.
*/
function initialize(address _logic, address _admin, bytes memory _data) public payable {
require(_implementation() == address(0));
InitializableUpgradeabilityProxy.initialize(_logic, _data);
assert(ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
_setAdmin(_admin);
}
}
/**
@title ILendingPoolAddressesProvider interface
@notice provides the interface to fetch the LendingPoolCore address
*/
contract ILendingPoolAddressesProvider {
function getLendingPool() public view returns (address);
function setLendingPoolImpl(address _pool) public;
function getLendingPoolCore() public view returns (address payable);
function setLendingPoolCoreImpl(address _lendingPoolCore) public;
function getLendingPoolConfigurator() public view returns (address);
function setLendingPoolConfiguratorImpl(address _configurator) public;
function getLendingPoolDataProvider() public view returns (address);
function setLendingPoolDataProviderImpl(address _provider) public;
function getLendingPoolParametersProvider() public view returns (address);
function setLendingPoolParametersProviderImpl(address _parametersProvider) public;
function getTokenDistributor() public view returns (address);
function setTokenDistributor(address _tokenDistributor) public;
function getFeeProvider() public view returns (address);
function setFeeProviderImpl(address _feeProvider) public;
function getLendingPoolLiquidationManager() public view returns (address);
function setLendingPoolLiquidationManager(address _manager) public;
function getLendingPoolManager() public view returns (address);
function setLendingPoolManager(address _lendingPoolManager) public;
function getPriceOracle() public view returns (address);
function setPriceOracle(address _priceOracle) public;
function getLendingRateOracle() public view returns (address);
function setLendingRateOracle(address _lendingRateOracle) public;
}
/**
* @title LendingPoolAddressesProvider contract
* @notice Is the main registry of the protocol. All the different components of the protocol are accessible
* through the addresses provider.
* @author Aave
**/
contract LendingPoolAddressesProvider is Ownable, ILendingPoolAddressesProvider, AddressStorage {
//events
event LendingPoolUpdated(address indexed newAddress);
event LendingPoolCoreUpdated(address indexed newAddress);
event LendingPoolParametersProviderUpdated(address indexed newAddress);
event LendingPoolManagerUpdated(address indexed newAddress);
event LendingPoolConfiguratorUpdated(address indexed newAddress);
event LendingPoolLiquidationManagerUpdated(address indexed newAddress);
event LendingPoolDataProviderUpdated(address indexed newAddress);
event EthereumAddressUpdated(address indexed newAddress);
event PriceOracleUpdated(address indexed newAddress);
event LendingRateOracleUpdated(address indexed newAddress);
event FeeProviderUpdated(address indexed newAddress);
event TokenDistributorUpdated(address indexed newAddress);
event ProxyCreated(bytes32 id, address indexed newAddress);
bytes32 private constant LENDING_POOL = "LENDING_POOL";
bytes32 private constant LENDING_POOL_CORE = "LENDING_POOL_CORE";
bytes32 private constant LENDING_POOL_CONFIGURATOR = "LENDING_POOL_CONFIGURATOR";
bytes32 private constant LENDING_POOL_PARAMETERS_PROVIDER = "PARAMETERS_PROVIDER";
bytes32 private constant LENDING_POOL_MANAGER = "LENDING_POOL_MANAGER";
bytes32 private constant LENDING_POOL_LIQUIDATION_MANAGER = "LIQUIDATION_MANAGER";
bytes32 private constant LENDING_POOL_FLASHLOAN_PROVIDER = "FLASHLOAN_PROVIDER";
bytes32 private constant DATA_PROVIDER = "DATA_PROVIDER";
bytes32 private constant ETHEREUM_ADDRESS = "ETHEREUM_ADDRESS";
bytes32 private constant PRICE_ORACLE = "PRICE_ORACLE";
bytes32 private constant LENDING_RATE_ORACLE = "LENDING_RATE_ORACLE";
bytes32 private constant FEE_PROVIDER = "FEE_PROVIDER";
bytes32 private constant WALLET_BALANCE_PROVIDER = "WALLET_BALANCE_PROVIDER";
bytes32 private constant TOKEN_DISTRIBUTOR = "TOKEN_DISTRIBUTOR";
/**
* @dev returns the address of the LendingPool proxy
* @return the lending pool proxy address
**/
function getLendingPool() public view returns (address) {
return getAddress(LENDING_POOL);
}
/**
* @dev updates the implementation of the lending pool
* @param _pool the new lending pool implementation
**/
function setLendingPoolImpl(address _pool) public onlyOwner {
updateImplInternal(LENDING_POOL, _pool);
emit LendingPoolUpdated(_pool);
}
/**
* @dev returns the address of the LendingPoolCore proxy
* @return the lending pool core proxy address
*/
function getLendingPoolCore() public view returns (address payable) {
address payable core = address(uint160(getAddress(LENDING_POOL_CORE)));
return core;
}
/**
* @dev updates the implementation of the lending pool core
* @param _lendingPoolCore the new lending pool core implementation
**/
function setLendingPoolCoreImpl(address _lendingPoolCore) public onlyOwner {
updateImplInternal(LENDING_POOL_CORE, _lendingPoolCore);
emit LendingPoolCoreUpdated(_lendingPoolCore);
}
/**
* @dev returns the address of the LendingPoolConfigurator proxy
* @return the lending pool configurator proxy address
**/
function getLendingPoolConfigurator() public view returns (address) {
return getAddress(LENDING_POOL_CONFIGURATOR);
}
/**
* @dev updates the implementation of the lending pool configurator
* @param _configurator the new lending pool configurator implementation
**/
function setLendingPoolConfiguratorImpl(address _configurator) public onlyOwner {
updateImplInternal(LENDING_POOL_CONFIGURATOR, _configurator);
emit LendingPoolConfiguratorUpdated(_configurator);
}
/**
* @dev returns the address of the LendingPoolDataProvider proxy
* @return the lending pool data provider proxy address
*/
function getLendingPoolDataProvider() public view returns (address) {
return getAddress(DATA_PROVIDER);
}
/**
* @dev updates the implementation of the lending pool data provider
* @param _provider the new lending pool data provider implementation
**/
function setLendingPoolDataProviderImpl(address _provider) public onlyOwner {
updateImplInternal(DATA_PROVIDER, _provider);
emit LendingPoolDataProviderUpdated(_provider);
}
/**
* @dev returns the address of the LendingPoolParametersProvider proxy
* @return the address of the Lending pool parameters provider proxy
**/
function getLendingPoolParametersProvider() public view returns (address) {
return getAddress(LENDING_POOL_PARAMETERS_PROVIDER);
}
/**
* @dev updates the implementation of the lending pool parameters provider
* @param _parametersProvider the new lending pool parameters provider implementation
**/
function setLendingPoolParametersProviderImpl(address _parametersProvider) public onlyOwner {
updateImplInternal(LENDING_POOL_PARAMETERS_PROVIDER, _parametersProvider);
emit LendingPoolParametersProviderUpdated(_parametersProvider);
}
/**
* @dev returns the address of the FeeProvider proxy
* @return the address of the Fee provider proxy
**/
function getFeeProvider() public view returns (address) {
return getAddress(FEE_PROVIDER);
}
/**
* @dev updates the implementation of the FeeProvider proxy
* @param _feeProvider the new lending pool fee provider implementation
**/
function setFeeProviderImpl(address _feeProvider) public onlyOwner {
updateImplInternal(FEE_PROVIDER, _feeProvider);
emit FeeProviderUpdated(_feeProvider);
}
/**
* @dev returns the address of the LendingPoolLiquidationManager. Since the manager is used
* through delegateCall within the LendingPool contract, the proxy contract pattern does not work properly hence
* the addresses are changed directly.
* @return the address of the Lending pool liquidation manager
**/
function getLendingPoolLiquidationManager() public view returns (address) {
return getAddress(LENDING_POOL_LIQUIDATION_MANAGER);
}
/**
* @dev updates the address of the Lending pool liquidation manager
* @param _manager the new lending pool liquidation manager address
**/
function setLendingPoolLiquidationManager(address _manager) public onlyOwner {
_setAddress(LENDING_POOL_LIQUIDATION_MANAGER, _manager);
emit LendingPoolLiquidationManagerUpdated(_manager);
}
/**
* @dev the functions below are storing specific addresses that are outside the context of the protocol
* hence the upgradable proxy pattern is not used
**/
function getLendingPoolManager() public view returns (address) {
return getAddress(LENDING_POOL_MANAGER);
}
function setLendingPoolManager(address _lendingPoolManager) public onlyOwner {
_setAddress(LENDING_POOL_MANAGER, _lendingPoolManager);
emit LendingPoolManagerUpdated(_lendingPoolManager);
}
function getPriceOracle() public view returns (address) {
return getAddress(PRICE_ORACLE);
}
function setPriceOracle(address _priceOracle) public onlyOwner {
_setAddress(PRICE_ORACLE, _priceOracle);
emit PriceOracleUpdated(_priceOracle);
}
function getLendingRateOracle() public view returns (address) {
return getAddress(LENDING_RATE_ORACLE);
}
function setLendingRateOracle(address _lendingRateOracle) public onlyOwner {
_setAddress(LENDING_RATE_ORACLE, _lendingRateOracle);
emit LendingRateOracleUpdated(_lendingRateOracle);
}
function getTokenDistributor() public view returns (address) {
return getAddress(TOKEN_DISTRIBUTOR);
}
function setTokenDistributor(address _tokenDistributor) public onlyOwner {
_setAddress(TOKEN_DISTRIBUTOR, _tokenDistributor);
emit TokenDistributorUpdated(_tokenDistributor);
}
/**
* @dev internal function to update the implementation of a specific component of the protocol
* @param _id the id of the contract to be updated
* @param _newAddress the address of the new implementation
**/
function updateImplInternal(bytes32 _id, address _newAddress) internal {
address payable proxyAddress = address(uint160(getAddress(_id)));
InitializableAdminUpgradeabilityProxy proxy = InitializableAdminUpgradeabilityProxy(proxyAddress);
bytes memory params = abi.encodeWithSignature("initialize(address)", address(this));
if (proxyAddress == address(0)) {
proxy = new InitializableAdminUpgradeabilityProxy();
proxy.initialize(_newAddress, address(this), params);
_setAddress(_id, address(proxy));
emit ProxyCreated(_id, address(proxy));
} else {
proxy.upgradeToAndCall(_newAddress, params);
}
}
}
contract UintStorage {
mapping(bytes32 => uint256) private uints;
function getUint(bytes32 _key) public view returns (uint256) {
return uints[_key];
}
function _setUint(bytes32 _key, uint256 _value) internal {
uints[_key] = _value;
}
}
/**
* @title LendingPoolParametersProvider
* @author Aave
* @notice stores the configuration parameters of the Lending Pool contract
**/
contract LendingPoolParametersProvider is VersionedInitializable {
uint256 private constant MAX_STABLE_RATE_BORROW_SIZE_PERCENT = 25;
uint256 private constant REBALANCE_DOWN_RATE_DELTA = (1e27)/5;
uint256 private constant FLASHLOAN_FEE_TOTAL = 35;
uint256 private constant FLASHLOAN_FEE_PROTOCOL = 3000;
uint256 constant private DATA_PROVIDER_REVISION = 0x1;
function getRevision() internal pure returns(uint256) {
return DATA_PROVIDER_REVISION;
}
/**
* @dev initializes the LendingPoolParametersProvider after it's added to the proxy
* @param _addressesProvider the address of the LendingPoolAddressesProvider
*/
function initialize(address _addressesProvider) public initializer {
}
/**
* @dev returns the maximum stable rate borrow size, in percentage of the available liquidity.
**/
function getMaxStableRateBorrowSizePercent() external pure returns (uint256) {
return MAX_STABLE_RATE_BORROW_SIZE_PERCENT;
}
/**
* @dev returns the delta between the current stable rate and the user stable rate at
* which the borrow position of the user will be rebalanced (scaled down)
**/
function getRebalanceDownRateDelta() external pure returns (uint256) {
return REBALANCE_DOWN_RATE_DELTA;
}
/**
* @dev returns the fee applied to a flashloan and the portion to redirect to the protocol, in basis points.
**/
function getFlashLoanFeesInBips() external pure returns (uint256, uint256) {
return (FLASHLOAN_FEE_TOTAL, FLASHLOAN_FEE_PROTOCOL);
}
}
/**
* @title CoreLibrary library
* @author Aave
* @notice Defines the data structures of the reserves and the user data
**/
library CoreLibrary {
using SafeMath for uint256;
using WadRayMath for uint256;
enum InterestRateMode {NONE, STABLE, VARIABLE}
uint256 internal constant SECONDS_PER_YEAR = 365 days;
struct UserReserveData {
//principal amount borrowed by the user.
uint256 principalBorrowBalance;
//cumulated variable borrow index for the user. Expressed in ray
uint256 lastVariableBorrowCumulativeIndex;
//origination fee cumulated by the user
uint256 originationFee;
// stable borrow rate at which the user has borrowed. Expressed in ray
uint256 stableBorrowRate;
uint40 lastUpdateTimestamp;
//defines if a specific deposit should or not be used as a collateral in borrows
bool useAsCollateral;
}
struct ReserveData {
/**
* @dev refer to the whitepaper, section 1.1 basic concepts for a formal description of these properties.
**/
//the liquidity index. Expressed in ray
uint256 lastLiquidityCumulativeIndex;
//the current supply rate. Expressed in ray
uint256 currentLiquidityRate;
//the total borrows of the reserve at a stable rate. Expressed in the currency decimals
uint256 totalBorrowsStable;
//the total borrows of the reserve at a variable rate. Expressed in the currency decimals
uint256 totalBorrowsVariable;
//the current variable borrow rate. Expressed in ray
uint256 currentVariableBorrowRate;
//the current stable borrow rate. Expressed in ray
uint256 currentStableBorrowRate;
//the current average stable borrow rate (weighted average of all the different stable rate loans). Expressed in ray
uint256 currentAverageStableBorrowRate;
//variable borrow index. Expressed in ray
uint256 lastVariableBorrowCumulativeIndex;
//the ltv of the reserve. Expressed in percentage (0-100)
uint256 baseLTVasCollateral;
//the liquidation threshold of the reserve. Expressed in percentage (0-100)
uint256 liquidationThreshold;
//the liquidation bonus of the reserve. Expressed in percentage
uint256 liquidationBonus;
//the decimals of the reserve asset
uint256 decimals;
/**
* @dev address of the aToken representing the asset
**/
address aTokenAddress;
/**
* @dev address of the interest rate strategy contract
**/
address interestRateStrategyAddress;
uint40 lastUpdateTimestamp;
// borrowingEnabled = true means users can borrow from this reserve
bool borrowingEnabled;
// usageAsCollateralEnabled = true means users can use this reserve as collateral
bool usageAsCollateralEnabled;
// isStableBorrowRateEnabled = true means users can borrow at a stable rate
bool isStableBorrowRateEnabled;
// isActive = true means the reserve has been activated and properly configured
bool isActive;
// isFreezed = true means the reserve only allows repays and redeems, but not deposits, new borrowings or rate swap
bool isFreezed;
}
/**
* @dev returns the ongoing normalized income for the reserve.
* a value of 1e27 means there is no income. As time passes, the income is accrued.
* A value of 2*1e27 means that the income of the reserve is double the initial amount.
* @param _reserve the reserve object
* @return the normalized income. expressed in ray
**/
function getNormalizedIncome(CoreLibrary.ReserveData storage _reserve)
internal
view
returns (uint256)
{
uint256 cumulated = calculateLinearInterest(
_reserve
.currentLiquidityRate,
_reserve
.lastUpdateTimestamp
)
.rayMul(_reserve.lastLiquidityCumulativeIndex);
return cumulated;
}
/**
* @dev Updates the liquidity cumulative index Ci and variable borrow cumulative index Bvc. Refer to the whitepaper for
* a formal specification.
* @param _self the reserve object
**/
function updateCumulativeIndexes(ReserveData storage _self) internal {
uint256 totalBorrows = getTotalBorrows(_self);
if (totalBorrows > 0) {
//only cumulating if there is any income being produced
uint256 cumulatedLiquidityInterest = calculateLinearInterest(
_self.currentLiquidityRate,
_self.lastUpdateTimestamp
);
_self.lastLiquidityCumulativeIndex = cumulatedLiquidityInterest.rayMul(
_self.lastLiquidityCumulativeIndex
);
uint256 cumulatedVariableBorrowInterest = calculateCompoundedInterest(
_self.currentVariableBorrowRate,
_self.lastUpdateTimestamp
);
_self.lastVariableBorrowCumulativeIndex = cumulatedVariableBorrowInterest.rayMul(
_self.lastVariableBorrowCumulativeIndex
);
}
}
/**
* @dev accumulates a predefined amount of asset to the reserve as a fixed, one time income. Used for example to accumulate
* the flashloan fee to the reserve, and spread it through the depositors.
* @param _self the reserve object
* @param _totalLiquidity the total liquidity available in the reserve
* @param _amount the amount to accomulate
**/
function cumulateToLiquidityIndex(
ReserveData storage _self,
uint256 _totalLiquidity,
uint256 _amount
) internal {
uint256 amountToLiquidityRatio = _amount.wadToRay().rayDiv(_totalLiquidity.wadToRay());
uint256 cumulatedLiquidity = amountToLiquidityRatio.add(WadRayMath.ray());
_self.lastLiquidityCumulativeIndex = cumulatedLiquidity.rayMul(
_self.lastLiquidityCumulativeIndex
);
}
/**
* @dev initializes a reserve
* @param _self the reserve object
* @param _aTokenAddress the address of the overlying atoken contract
* @param _decimals the number of decimals of the underlying asset
* @param _interestRateStrategyAddress the address of the interest rate strategy contract
**/
function init(
ReserveData storage _self,
address _aTokenAddress,
uint256 _decimals,
address _interestRateStrategyAddress
) external {
require(_self.aTokenAddress == address(0), "Reserve has already been initialized");
if (_self.lastLiquidityCumulativeIndex == 0) {
//if the reserve has not been initialized yet
_self.lastLiquidityCumulativeIndex = WadRayMath.ray();
}
if (_self.lastVariableBorrowCumulativeIndex == 0) {
_self.lastVariableBorrowCumulativeIndex = WadRayMath.ray();
}
_self.aTokenAddress = _aTokenAddress;
_self.decimals = _decimals;
_self.interestRateStrategyAddress = _interestRateStrategyAddress;
_self.isActive = true;
_self.isFreezed = false;
}
/**
* @dev enables borrowing on a reserve
* @param _self the reserve object
* @param _stableBorrowRateEnabled true if the stable borrow rate must be enabled by default, false otherwise
**/
function enableBorrowing(ReserveData storage _self, bool _stableBorrowRateEnabled) external {
require(_self.borrowingEnabled == false, "Reserve is already enabled");
_self.borrowingEnabled = true;
_self.isStableBorrowRateEnabled = _stableBorrowRateEnabled;
}
/**
* @dev disables borrowing on a reserve
* @param _self the reserve object
**/
function disableBorrowing(ReserveData storage _self) external {
_self.borrowingEnabled = false;
}
/**
* @dev enables a reserve to be used as collateral
* @param _self the reserve object
* @param _baseLTVasCollateral the loan to value of the asset when used as collateral
* @param _liquidationThreshold the threshold at which loans using this asset as collateral will be considered undercollateralized
* @param _liquidationBonus the bonus liquidators receive to liquidate this asset
**/
function enableAsCollateral(
ReserveData storage _self,
uint256 _baseLTVasCollateral,
uint256 _liquidationThreshold,
uint256 _liquidationBonus
) external {
require(
_self.usageAsCollateralEnabled == false,
"Reserve is already enabled as collateral"
);
_self.usageAsCollateralEnabled = true;
_self.baseLTVasCollateral = _baseLTVasCollateral;
_self.liquidationThreshold = _liquidationThreshold;
_self.liquidationBonus = _liquidationBonus;
if (_self.lastLiquidityCumulativeIndex == 0)
_self.lastLiquidityCumulativeIndex = WadRayMath.ray();
}
/**
* @dev disables a reserve as collateral
* @param _self the reserve object
**/
function disableAsCollateral(ReserveData storage _self) external {
_self.usageAsCollateralEnabled = false;
}
/**
* @dev calculates the compounded borrow balance of a user
* @param _self the userReserve object
* @param _reserve the reserve object
* @return the user compounded borrow balance
**/
function getCompoundedBorrowBalance(
CoreLibrary.UserReserveData storage _self,
CoreLibrary.ReserveData storage _reserve
) internal view returns (uint256) {
if (_self.principalBorrowBalance == 0) return 0;
uint256 principalBorrowBalanceRay = _self.principalBorrowBalance.wadToRay();
uint256 compoundedBalance = 0;
uint256 cumulatedInterest = 0;
if (_self.stableBorrowRate > 0) {
cumulatedInterest = calculateCompoundedInterest(
_self.stableBorrowRate,
_self.lastUpdateTimestamp
);
} else {
//variable interest
cumulatedInterest = calculateCompoundedInterest(
_reserve
.currentVariableBorrowRate,
_reserve
.lastUpdateTimestamp
)
.rayMul(_reserve.lastVariableBorrowCumulativeIndex)
.rayDiv(_self.lastVariableBorrowCumulativeIndex);
}
compoundedBalance = principalBorrowBalanceRay.rayMul(cumulatedInterest).rayToWad();
if (compoundedBalance == _self.principalBorrowBalance) {
//solium-disable-next-line
if (_self.lastUpdateTimestamp != block.timestamp) {
//no interest cumulation because of the rounding - we add 1 wei
//as symbolic cumulated interest to avoid interest free loans.
return _self.principalBorrowBalance.add(1 wei);
}
}
return compoundedBalance;
}
/**
* @dev increases the total borrows at a stable rate on a specific reserve and updates the
* average stable rate consequently
* @param _reserve the reserve object
* @param _amount the amount to add to the total borrows stable
* @param _rate the rate at which the amount has been borrowed
**/
function increaseTotalBorrowsStableAndUpdateAverageRate(
ReserveData storage _reserve,
uint256 _amount,
uint256 _rate
) internal {
uint256 previousTotalBorrowStable = _reserve.totalBorrowsStable;
//updating reserve borrows stable
_reserve.totalBorrowsStable = _reserve.totalBorrowsStable.add(_amount);
//update the average stable rate
//weighted average of all the borrows
uint256 weightedLastBorrow = _amount.wadToRay().rayMul(_rate);
uint256 weightedPreviousTotalBorrows = previousTotalBorrowStable.wadToRay().rayMul(
_reserve.currentAverageStableBorrowRate
);
_reserve.currentAverageStableBorrowRate = weightedLastBorrow
.add(weightedPreviousTotalBorrows)
.rayDiv(_reserve.totalBorrowsStable.wadToRay());
}
/**
* @dev decreases the total borrows at a stable rate on a specific reserve and updates the
* average stable rate consequently
* @param _reserve the reserve object
* @param _amount the amount to substract to the total borrows stable
* @param _rate the rate at which the amount has been repaid
**/
function decreaseTotalBorrowsStableAndUpdateAverageRate(
ReserveData storage _reserve,
uint256 _amount,
uint256 _rate
) internal {
require(_reserve.totalBorrowsStable >= _amount, "Invalid amount to decrease");
uint256 previousTotalBorrowStable = _reserve.totalBorrowsStable;
//updating reserve borrows stable
_reserve.totalBorrowsStable = _reserve.totalBorrowsStable.sub(_amount);
if (_reserve.totalBorrowsStable == 0) {
_reserve.currentAverageStableBorrowRate = 0; //no income if there are no stable rate borrows
return;
}
//update the average stable rate
//weighted average of all the borrows
uint256 weightedLastBorrow = _amount.wadToRay().rayMul(_rate);
uint256 weightedPreviousTotalBorrows = previousTotalBorrowStable.wadToRay().rayMul(
_reserve.currentAverageStableBorrowRate
);
require(
weightedPreviousTotalBorrows >= weightedLastBorrow,
"The amounts to subtract don't match"
);
_reserve.currentAverageStableBorrowRate = weightedPreviousTotalBorrows
.sub(weightedLastBorrow)
.rayDiv(_reserve.totalBorrowsStable.wadToRay());
}
/**
* @dev increases the total borrows at a variable rate
* @param _reserve the reserve object
* @param _amount the amount to add to the total borrows variable
**/
function increaseTotalBorrowsVariable(ReserveData storage _reserve, uint256 _amount) internal {
_reserve.totalBorrowsVariable = _reserve.totalBorrowsVariable.add(_amount);
}
/**
* @dev decreases the total borrows at a variable rate
* @param _reserve the reserve object
* @param _amount the amount to substract to the total borrows variable
**/
function decreaseTotalBorrowsVariable(ReserveData storage _reserve, uint256 _amount) internal {
require(
_reserve.totalBorrowsVariable >= _amount,
"The amount that is being subtracted from the variable total borrows is incorrect"
);
_reserve.totalBorrowsVariable = _reserve.totalBorrowsVariable.sub(_amount);
}
/**
* @dev function to calculate the interest using a linear interest rate formula
* @param _rate the interest rate, in ray
* @param _lastUpdateTimestamp the timestamp of the last update of the interest
* @return the interest rate linearly accumulated during the timeDelta, in ray
**/
function calculateLinearInterest(uint256 _rate, uint40 _lastUpdateTimestamp)
internal
view
returns (uint256)
{
//solium-disable-next-line
uint256 timeDifference = block.timestamp.sub(uint256(_lastUpdateTimestamp));
uint256 timeDelta = timeDifference.wadToRay().rayDiv(SECONDS_PER_YEAR.wadToRay());
return _rate.rayMul(timeDelta).add(WadRayMath.ray());
}
/**
* @dev function to calculate the interest using a compounded interest rate formula
* @param _rate the interest rate, in ray
* @param _lastUpdateTimestamp the timestamp of the last update of the interest
* @return the interest rate compounded during the timeDelta, in ray
**/
function calculateCompoundedInterest(uint256 _rate, uint40 _lastUpdateTimestamp)
internal
view
returns (uint256)
{
//solium-disable-next-line
uint256 timeDifference = block.timestamp.sub(uint256(_lastUpdateTimestamp));
uint256 ratePerSecond = _rate.div(SECONDS_PER_YEAR);
return ratePerSecond.add(WadRayMath.ray()).rayPow(timeDifference);
}
/**
* @dev returns the total borrows on the reserve
* @param _reserve the reserve object
* @return the total borrows (stable + variable)
**/
function getTotalBorrows(CoreLibrary.ReserveData storage _reserve)
internal
view
returns (uint256)
{
return _reserve.totalBorrowsStable.add(_reserve.totalBorrowsVariable);
}
}
/**
* @title IPriceOracleGetter interface
* @notice Interface for the Aave price oracle.
**/
interface IPriceOracleGetter {
/**
* @dev returns the asset price in ETH
* @param _asset the address of the asset
* @return the ETH price of the asset
**/
function getAssetPrice(address _asset) external view returns (uint256);
}
/**
* @title IFeeProvider interface
* @notice Interface for the Aave fee provider.
**/
interface IFeeProvider {
function calculateLoanOriginationFee(address _user, uint256 _amount) external view returns (uint256);
function getLoanOriginationFeePercentage() external view returns (uint256);
}
/**
* @title LendingPoolDataProvider contract
* @author Aave
* @notice Implements functions to fetch data from the core, and aggregate them in order to allow computation
* on the compounded balances and the account balances in ETH
**/
contract LendingPoolDataProvider is VersionedInitializable {
using SafeMath for uint256;
using WadRayMath for uint256;
LendingPoolCore public core;
LendingPoolAddressesProvider public addressesProvider;
/**
* @dev specifies the health factor threshold at which the user position is liquidated.
* 1e18 by default, if the health factor drops below 1e18, the loan can be liquidated.
**/
uint256 public constant HEALTH_FACTOR_LIQUIDATION_THRESHOLD = 1e18;
uint256 public constant DATA_PROVIDER_REVISION = 0x1;
function getRevision() internal pure returns (uint256) {
return DATA_PROVIDER_REVISION;
}
function initialize(LendingPoolAddressesProvider _addressesProvider) public initializer {
addressesProvider = _addressesProvider;
core = LendingPoolCore(_addressesProvider.getLendingPoolCore());
}
/**
* @dev struct to hold calculateUserGlobalData() local computations
**/
struct UserGlobalDataLocalVars {
uint256 reserveUnitPrice;
uint256 tokenUnit;
uint256 compoundedLiquidityBalance;
uint256 compoundedBorrowBalance;
uint256 reserveDecimals;
uint256 baseLtv;
uint256 liquidationThreshold;
uint256 originationFee;
bool usageAsCollateralEnabled;
bool userUsesReserveAsCollateral;
address currentReserve;
}
/**
* @dev calculates the user data across the reserves.
* this includes the total liquidity/collateral/borrow balances in ETH,
* the average Loan To Value, the average Liquidation Ratio, and the Health factor.
* @param _user the address of the user
* @return the total liquidity, total collateral, total borrow balances of the user in ETH.
* also the average Ltv, liquidation threshold, and the health factor
**/
function calculateUserGlobalData(address _user)
public
view
returns (
uint256 totalLiquidityBalanceETH,
uint256 totalCollateralBalanceETH,
uint256 totalBorrowBalanceETH,
uint256 totalFeesETH,
uint256 currentLtv,
uint256 currentLiquidationThreshold,
uint256 healthFactor,
bool healthFactorBelowThreshold
)
{
IPriceOracleGetter oracle = IPriceOracleGetter(addressesProvider.getPriceOracle());
// Usage of a memory struct of vars to avoid "Stack too deep" errors due to local variables
UserGlobalDataLocalVars memory vars;
address[] memory reserves = core.getReserves();
for (uint256 i = 0; i < reserves.length; i++) {
vars.currentReserve = reserves[i];
(
vars.compoundedLiquidityBalance,
vars.compoundedBorrowBalance,
vars.originationFee,
vars.userUsesReserveAsCollateral
) = core.getUserBasicReserveData(vars.currentReserve, _user);
if (vars.compoundedLiquidityBalance == 0 && vars.compoundedBorrowBalance == 0) {
continue;
}
//fetch reserve data
(
vars.reserveDecimals,
vars.baseLtv,
vars.liquidationThreshold,
vars.usageAsCollateralEnabled
) = core.getReserveConfiguration(vars.currentReserve);
vars.tokenUnit = 10 ** vars.reserveDecimals;
vars.reserveUnitPrice = oracle.getAssetPrice(vars.currentReserve);
//liquidity and collateral balance
if (vars.compoundedLiquidityBalance > 0) {
uint256 liquidityBalanceETH = vars
.reserveUnitPrice
.mul(vars.compoundedLiquidityBalance)
.div(vars.tokenUnit);
totalLiquidityBalanceETH = totalLiquidityBalanceETH.add(liquidityBalanceETH);
if (vars.usageAsCollateralEnabled && vars.userUsesReserveAsCollateral) {
totalCollateralBalanceETH = totalCollateralBalanceETH.add(liquidityBalanceETH);
currentLtv = currentLtv.add(liquidityBalanceETH.mul(vars.baseLtv));
currentLiquidationThreshold = currentLiquidationThreshold.add(
liquidityBalanceETH.mul(vars.liquidationThreshold)
);
}
}
if (vars.compoundedBorrowBalance > 0) {
totalBorrowBalanceETH = totalBorrowBalanceETH.add(
vars.reserveUnitPrice.mul(vars.compoundedBorrowBalance).div(vars.tokenUnit)
);
totalFeesETH = totalFeesETH.add(
vars.originationFee.mul(vars.reserveUnitPrice).div(vars.tokenUnit)
);
}
}
currentLtv = totalCollateralBalanceETH > 0 ? currentLtv.div(totalCollateralBalanceETH) : 0;
currentLiquidationThreshold = totalCollateralBalanceETH > 0
? currentLiquidationThreshold.div(totalCollateralBalanceETH)
: 0;
healthFactor = calculateHealthFactorFromBalancesInternal(
totalCollateralBalanceETH,
totalBorrowBalanceETH,
totalFeesETH,
currentLiquidationThreshold
);
healthFactorBelowThreshold = healthFactor < HEALTH_FACTOR_LIQUIDATION_THRESHOLD;
}
struct balanceDecreaseAllowedLocalVars {
uint256 decimals;
uint256 collateralBalanceETH;
uint256 borrowBalanceETH;
uint256 totalFeesETH;
uint256 currentLiquidationThreshold;
uint256 reserveLiquidationThreshold;
uint256 amountToDecreaseETH;
uint256 collateralBalancefterDecrease;
uint256 liquidationThresholdAfterDecrease;
uint256 healthFactorAfterDecrease;
bool reserveUsageAsCollateralEnabled;
}
/**
* @dev check if a specific balance decrease is allowed (i.e. doesn't bring the user borrow position health factor under 1e18)
* @param _reserve the address of the reserve
* @param _user the address of the user
* @param _amount the amount to decrease
* @return true if the decrease of the balance is allowed
**/
function balanceDecreaseAllowed(address _reserve, address _user, uint256 _amount)
external
view
returns (bool)
{
// Usage of a memory struct of vars to avoid "Stack too deep" errors due to local variables
balanceDecreaseAllowedLocalVars memory vars;
(
vars.decimals,
,
vars.reserveLiquidationThreshold,
vars.reserveUsageAsCollateralEnabled
) = core.getReserveConfiguration(_reserve);
if (
!vars.reserveUsageAsCollateralEnabled ||
!core.isUserUseReserveAsCollateralEnabled(_reserve, _user)
) {
return true; //if reserve is not used as collateral, no reasons to block the transfer
}
(
,
vars.collateralBalanceETH,
vars.borrowBalanceETH,
vars.totalFeesETH,
,
vars.currentLiquidationThreshold,
,
) = calculateUserGlobalData(_user);
if (vars.borrowBalanceETH == 0) {
return true; //no borrows - no reasons to block the transfer
}
IPriceOracleGetter oracle = IPriceOracleGetter(addressesProvider.getPriceOracle());
vars.amountToDecreaseETH = oracle.getAssetPrice(_reserve).mul(_amount).div(
10 ** vars.decimals
);
vars.collateralBalancefterDecrease = vars.collateralBalanceETH.sub(
vars.amountToDecreaseETH
);
//if there is a borrow, there can't be 0 collateral
if (vars.collateralBalancefterDecrease == 0) {
return false;
}
vars.liquidationThresholdAfterDecrease = vars
.collateralBalanceETH
.mul(vars.currentLiquidationThreshold)
.sub(vars.amountToDecreaseETH.mul(vars.reserveLiquidationThreshold))
.div(vars.collateralBalancefterDecrease);
uint256 healthFactorAfterDecrease = calculateHealthFactorFromBalancesInternal(
vars.collateralBalancefterDecrease,
vars.borrowBalanceETH,
vars.totalFeesETH,
vars.liquidationThresholdAfterDecrease
);
return healthFactorAfterDecrease > HEALTH_FACTOR_LIQUIDATION_THRESHOLD;
}
/**
* @notice calculates the amount of collateral needed in ETH to cover a new borrow.
* @param _reserve the reserve from which the user wants to borrow
* @param _amount the amount the user wants to borrow
* @param _fee the fee for the amount that the user needs to cover
* @param _userCurrentBorrowBalanceTH the current borrow balance of the user (before the borrow)
* @param _userCurrentLtv the average ltv of the user given his current collateral
* @return the total amount of collateral in ETH to cover the current borrow balance + the new amount + fee
**/
function calculateCollateralNeededInETH(
address _reserve,
uint256 _amount,
uint256 _fee,
uint256 _userCurrentBorrowBalanceTH,
uint256 _userCurrentFeesETH,
uint256 _userCurrentLtv
) external view returns (uint256) {
uint256 reserveDecimals = core.getReserveDecimals(_reserve);
IPriceOracleGetter oracle = IPriceOracleGetter(addressesProvider.getPriceOracle());
uint256 requestedBorrowAmountETH = oracle
.getAssetPrice(_reserve)
.mul(_amount.add(_fee))
.div(10 ** reserveDecimals); //price is in ether
//add the current already borrowed amount to the amount requested to calculate the total collateral needed.
uint256 collateralNeededInETH = _userCurrentBorrowBalanceTH
.add(_userCurrentFeesETH)
.add(requestedBorrowAmountETH)
.mul(100)
.div(_userCurrentLtv); //LTV is calculated in percentage
return collateralNeededInETH;
}
/**
* @dev calculates the equivalent amount in ETH that an user can borrow, depending on the available collateral and the
* average Loan To Value.
* @param collateralBalanceETH the total collateral balance
* @param borrowBalanceETH the total borrow balance
* @param totalFeesETH the total fees
* @param ltv the average loan to value
* @return the amount available to borrow in ETH for the user
**/
function calculateAvailableBorrowsETHInternal(
uint256 collateralBalanceETH,
uint256 borrowBalanceETH,
uint256 totalFeesETH,
uint256 ltv
) internal view returns (uint256) {
uint256 availableBorrowsETH = collateralBalanceETH.mul(ltv).div(100); //ltv is in percentage
if (availableBorrowsETH < borrowBalanceETH) {
return 0;
}
availableBorrowsETH = availableBorrowsETH.sub(borrowBalanceETH.add(totalFeesETH));
//calculate fee
uint256 borrowFee = IFeeProvider(addressesProvider.getFeeProvider())
.calculateLoanOriginationFee(msg.sender, availableBorrowsETH);
return availableBorrowsETH.sub(borrowFee);
}
/**
* @dev calculates the health factor from the corresponding balances
* @param collateralBalanceETH the total collateral balance in ETH
* @param borrowBalanceETH the total borrow balance in ETH
* @param totalFeesETH the total fees in ETH
* @param liquidationThreshold the avg liquidation threshold
**/
function calculateHealthFactorFromBalancesInternal(
uint256 collateralBalanceETH,
uint256 borrowBalanceETH,
uint256 totalFeesETH,
uint256 liquidationThreshold
) internal pure returns (uint256) {
if (borrowBalanceETH == 0) return uint256(-1);
return
(collateralBalanceETH.mul(liquidationThreshold).div(100)).wadDiv(
borrowBalanceETH.add(totalFeesETH)
);
}
/**
* @dev returns the health factor liquidation threshold
**/
function getHealthFactorLiquidationThreshold() public pure returns (uint256) {
return HEALTH_FACTOR_LIQUIDATION_THRESHOLD;
}
/**
* @dev accessory functions to fetch data from the lendingPoolCore
**/
function getReserveConfigurationData(address _reserve)
external
view
returns (
uint256 ltv,
uint256 liquidationThreshold,
uint256 liquidationBonus,
address rateStrategyAddress,
bool usageAsCollateralEnabled,
bool borrowingEnabled,
bool stableBorrowRateEnabled,
bool isActive
)
{
(, ltv, liquidationThreshold, usageAsCollateralEnabled) = core.getReserveConfiguration(
_reserve
);
stableBorrowRateEnabled = core.getReserveIsStableBorrowRateEnabled(_reserve);
borrowingEnabled = core.isReserveBorrowingEnabled(_reserve);
isActive = core.getReserveIsActive(_reserve);
liquidationBonus = core.getReserveLiquidationBonus(_reserve);
rateStrategyAddress = core.getReserveInterestRateStrategyAddress(_reserve);
}
function getReserveData(address _reserve)
external
view
returns (
uint256 totalLiquidity,
uint256 availableLiquidity,
uint256 totalBorrowsStable,
uint256 totalBorrowsVariable,
uint256 liquidityRate,
uint256 variableBorrowRate,
uint256 stableBorrowRate,
uint256 averageStableBorrowRate,
uint256 utilizationRate,
uint256 liquidityIndex,
uint256 variableBorrowIndex,
address aTokenAddress,
uint40 lastUpdateTimestamp
)
{
totalLiquidity = core.getReserveTotalLiquidity(_reserve);
availableLiquidity = core.getReserveAvailableLiquidity(_reserve);
totalBorrowsStable = core.getReserveTotalBorrowsStable(_reserve);
totalBorrowsVariable = core.getReserveTotalBorrowsVariable(_reserve);
liquidityRate = core.getReserveCurrentLiquidityRate(_reserve);
variableBorrowRate = core.getReserveCurrentVariableBorrowRate(_reserve);
stableBorrowRate = core.getReserveCurrentStableBorrowRate(_reserve);
averageStableBorrowRate = core.getReserveCurrentAverageStableBorrowRate(_reserve);
utilizationRate = core.getReserveUtilizationRate(_reserve);
liquidityIndex = core.getReserveLiquidityCumulativeIndex(_reserve);
variableBorrowIndex = core.getReserveVariableBorrowsCumulativeIndex(_reserve);
aTokenAddress = core.getReserveATokenAddress(_reserve);
lastUpdateTimestamp = core.getReserveLastUpdate(_reserve);
}
function getUserAccountData(address _user)
external
view
returns (
uint256 totalLiquidityETH,
uint256 totalCollateralETH,
uint256 totalBorrowsETH,
uint256 totalFeesETH,
uint256 availableBorrowsETH,
uint256 currentLiquidationThreshold,
uint256 ltv,
uint256 healthFactor
)
{
(
totalLiquidityETH,
totalCollateralETH,
totalBorrowsETH,
totalFeesETH,
ltv,
currentLiquidationThreshold,
healthFactor,
) = calculateUserGlobalData(_user);
availableBorrowsETH = calculateAvailableBorrowsETHInternal(
totalCollateralETH,
totalBorrowsETH,
totalFeesETH,
ltv
);
}
function getUserReserveData(address _reserve, address _user)
external
view
returns (
uint256 currentATokenBalance,
uint256 currentBorrowBalance,
uint256 principalBorrowBalance,
uint256 borrowRateMode,
uint256 borrowRate,
uint256 liquidityRate,
uint256 originationFee,
uint256 variableBorrowIndex,
uint256 lastUpdateTimestamp,
bool usageAsCollateralEnabled
)
{
currentATokenBalance = AToken(core.getReserveATokenAddress(_reserve)).balanceOf(_user);
CoreLibrary.InterestRateMode mode = core.getUserCurrentBorrowRateMode(_reserve, _user);
(principalBorrowBalance, currentBorrowBalance, ) = core.getUserBorrowBalances(
_reserve,
_user
);
//default is 0, if mode == CoreLibrary.InterestRateMode.NONE
if (mode == CoreLibrary.InterestRateMode.STABLE) {
borrowRate = core.getUserCurrentStableBorrowRate(_reserve, _user);
} else if (mode == CoreLibrary.InterestRateMode.VARIABLE) {
borrowRate = core.getReserveCurrentVariableBorrowRate(_reserve);
}
borrowRateMode = uint256(mode);
liquidityRate = core.getReserveCurrentLiquidityRate(_reserve);
originationFee = core.getUserOriginationFee(_reserve, _user);
variableBorrowIndex = core.getUserVariableBorrowCumulativeIndex(_reserve, _user);
lastUpdateTimestamp = core.getUserLastUpdate(_reserve, _user);
usageAsCollateralEnabled = core.isUserUseReserveAsCollateralEnabled(_reserve, _user);
}
}
/**
* @title Aave ERC20 AToken
*
* @dev Implementation of the interest bearing token for the DLP protocol.
* @author Aave
*/
contract AToken is ERC20, ERC20Detailed {
using WadRayMath for uint256;
uint256 public constant UINT_MAX_VALUE = uint256(-1);
/**
* @dev emitted after the redeem action
* @param _from the address performing the redeem
* @param _value the amount to be redeemed
* @param _fromBalanceIncrease the cumulated balance since the last update of the user
* @param _fromIndex the last index of the user
**/
event Redeem(
address indexed _from,
uint256 _value,
uint256 _fromBalanceIncrease,
uint256 _fromIndex
);
/**
* @dev emitted after the mint action
* @param _from the address performing the mint
* @param _value the amount to be minted
* @param _fromBalanceIncrease the cumulated balance since the last update of the user
* @param _fromIndex the last index of the user
**/
event MintOnDeposit(
address indexed _from,
uint256 _value,
uint256 _fromBalanceIncrease,
uint256 _fromIndex
);
/**
* @dev emitted during the liquidation action, when the liquidator reclaims the underlying
* asset
* @param _from the address from which the tokens are being burned
* @param _value the amount to be burned
* @param _fromBalanceIncrease the cumulated balance since the last update of the user
* @param _fromIndex the last index of the user
**/
event BurnOnLiquidation(
address indexed _from,
uint256 _value,
uint256 _fromBalanceIncrease,
uint256 _fromIndex
);
/**
* @dev emitted during the transfer action
* @param _from the address from which the tokens are being transferred
* @param _to the adress of the destination
* @param _value the amount to be minted
* @param _fromBalanceIncrease the cumulated balance since the last update of the user
* @param _toBalanceIncrease the cumulated balance since the last update of the destination
* @param _fromIndex the last index of the user
* @param _toIndex the last index of the liquidator
**/
event BalanceTransfer(
address indexed _from,
address indexed _to,
uint256 _value,
uint256 _fromBalanceIncrease,
uint256 _toBalanceIncrease,
uint256 _fromIndex,
uint256 _toIndex
);
/**
* @dev emitted when the accumulation of the interest
* by an user is redirected to another user
* @param _from the address from which the interest is being redirected
* @param _to the adress of the destination
* @param _fromBalanceIncrease the cumulated balance since the last update of the user
* @param _fromIndex the last index of the user
**/
event InterestStreamRedirected(
address indexed _from,
address indexed _to,
uint256 _redirectedBalance,
uint256 _fromBalanceIncrease,
uint256 _fromIndex
);
/**
* @dev emitted when the redirected balance of an user is being updated
* @param _targetAddress the address of which the balance is being updated
* @param _targetBalanceIncrease the cumulated balance since the last update of the target
* @param _targetIndex the last index of the user
* @param _redirectedBalanceAdded the redirected balance being added
* @param _redirectedBalanceRemoved the redirected balance being removed
**/
event RedirectedBalanceUpdated(
address indexed _targetAddress,
uint256 _targetBalanceIncrease,
uint256 _targetIndex,
uint256 _redirectedBalanceAdded,
uint256 _redirectedBalanceRemoved
);
event InterestRedirectionAllowanceChanged(
address indexed _from,
address indexed _to
);
address public underlyingAssetAddress;
mapping (address => uint256) private userIndexes;
mapping (address => address) private interestRedirectionAddresses;
mapping (address => uint256) private redirectedBalances;
mapping (address => address) private interestRedirectionAllowances;
LendingPoolAddressesProvider private addressesProvider;
LendingPoolCore private core;
LendingPool private pool;
LendingPoolDataProvider private dataProvider;
modifier onlyLendingPool {
require(
msg.sender == address(pool),
"The caller of this function must be a lending pool"
);
_;
}
modifier whenTransferAllowed(address _from, uint256 _amount) {
require(isTransferAllowed(_from, _amount), "Transfer cannot be allowed.");
_;
}
constructor(
LendingPoolAddressesProvider _addressesProvider,
address _underlyingAsset,
uint8 _underlyingAssetDecimals,
string memory _name,
string memory _symbol
) public ERC20Detailed(_name, _symbol, _underlyingAssetDecimals) {
addressesProvider = _addressesProvider;
core = LendingPoolCore(addressesProvider.getLendingPoolCore());
pool = LendingPool(addressesProvider.getLendingPool());
dataProvider = LendingPoolDataProvider(addressesProvider.getLendingPoolDataProvider());
underlyingAssetAddress = _underlyingAsset;
}
/**
* @notice ERC20 implementation internal function backing transfer() and transferFrom()
* @dev validates the transfer before allowing it. NOTE: This is not standard ERC20 behavior
**/
function _transfer(address _from, address _to, uint256 _amount) internal whenTransferAllowed(_from, _amount) {
executeTransferInternal(_from, _to, _amount);
}
/**
* @dev redirects the interest generated to a target address.
* when the interest is redirected, the user balance is added to
* the recepient redirected balance.
* @param _to the address to which the interest will be redirected
**/
function redirectInterestStream(address _to) external {
redirectInterestStreamInternal(msg.sender, _to);
}
/**
* @dev redirects the interest generated by _from to a target address.
* when the interest is redirected, the user balance is added to
* the recepient redirected balance. The caller needs to have allowance on
* the interest redirection to be able to execute the function.
* @param _from the address of the user whom interest is being redirected
* @param _to the address to which the interest will be redirected
**/
function redirectInterestStreamOf(address _from, address _to) external {
require(
msg.sender == interestRedirectionAllowances[_from],
"Caller is not allowed to redirect the interest of the user"
);
redirectInterestStreamInternal(_from,_to);
}
/**
* @dev gives allowance to an address to execute the interest redirection
* on behalf of the caller.
* @param _to the address to which the interest will be redirected. Pass address(0) to reset
* the allowance.
**/
function allowInterestRedirectionTo(address _to) external {
require(_to != msg.sender, "User cannot give allowance to himself");
interestRedirectionAllowances[msg.sender] = _to;
emit InterestRedirectionAllowanceChanged(
msg.sender,
_to
);
}
/**
* @dev redeems aToken for the underlying asset
* @param _amount the amount being redeemed
**/
function redeem(uint256 _amount) external {
require(_amount > 0, "Amount to redeem needs to be > 0");
//cumulates the balance of the user
(,
uint256 currentBalance,
uint256 balanceIncrease,
uint256 index) = cumulateBalanceInternal(msg.sender);
uint256 amountToRedeem = _amount;
//if amount is equal to uint(-1), the user wants to redeem everything
if(_amount == UINT_MAX_VALUE){
amountToRedeem = currentBalance;
}
require(amountToRedeem <= currentBalance, "User cannot redeem more than the available balance");
//check that the user is allowed to redeem the amount
require(isTransferAllowed(msg.sender, amountToRedeem), "Transfer cannot be allowed.");
//if the user is redirecting his interest towards someone else,
//we update the redirected balance of the redirection address by adding the accrued interest,
//and removing the amount to redeem
updateRedirectedBalanceOfRedirectionAddressInternal(msg.sender, balanceIncrease, amountToRedeem);
// burns tokens equivalent to the amount requested
_burn(msg.sender, amountToRedeem);
bool userIndexReset = false;
//reset the user data if the remaining balance is 0
if(currentBalance.sub(amountToRedeem) == 0){
userIndexReset = resetDataOnZeroBalanceInternal(msg.sender);
}
// executes redeem of the underlying asset
pool.redeemUnderlying(
underlyingAssetAddress,
msg.sender,
amountToRedeem,
currentBalance.sub(amountToRedeem)
);
emit Redeem(msg.sender, amountToRedeem, balanceIncrease, userIndexReset ? 0 : index);
}
/**
* @dev mints token in the event of users depositing the underlying asset into the lending pool
* only lending pools can call this function
* @param _account the address receiving the minted tokens
* @param _amount the amount of tokens to mint
*/
function mintOnDeposit(address _account, uint256 _amount) external onlyLendingPool {
//cumulates the balance of the user
(,
,
uint256 balanceIncrease,
uint256 index) = cumulateBalanceInternal(_account);
//if the user is redirecting his interest towards someone else,
//we update the redirected balance of the redirection address by adding the accrued interest
//and the amount deposited
updateRedirectedBalanceOfRedirectionAddressInternal(_account, balanceIncrease.add(_amount), 0);
//mint an equivalent amount of tokens to cover the new deposit
_mint(_account, _amount);
emit MintOnDeposit(_account, _amount, balanceIncrease, index);
}
/**
* @dev burns token in the event of a borrow being liquidated, in case the liquidators reclaims the underlying asset
* Transfer of the liquidated asset is executed by the lending pool contract.
* only lending pools can call this function
* @param _account the address from which burn the aTokens
* @param _value the amount to burn
**/
function burnOnLiquidation(address _account, uint256 _value) external onlyLendingPool {
//cumulates the balance of the user being liquidated
(,uint256 accountBalance,uint256 balanceIncrease,uint256 index) = cumulateBalanceInternal(_account);
//adds the accrued interest and substracts the burned amount to
//the redirected balance
updateRedirectedBalanceOfRedirectionAddressInternal(_account, balanceIncrease, _value);
//burns the requested amount of tokens
_burn(_account, _value);
bool userIndexReset = false;
//reset the user data if the remaining balance is 0
if(accountBalance.sub(_value) == 0){
userIndexReset = resetDataOnZeroBalanceInternal(_account);
}
emit BurnOnLiquidation(_account, _value, balanceIncrease, userIndexReset ? 0 : index);
}
/**
* @dev transfers tokens in the event of a borrow being liquidated, in case the liquidators reclaims the aToken
* only lending pools can call this function
* @param _from the address from which transfer the aTokens
* @param _to the destination address
* @param _value the amount to transfer
**/
function transferOnLiquidation(address _from, address _to, uint256 _value) external onlyLendingPool {
//being a normal transfer, the Transfer() and BalanceTransfer() are emitted
//so no need to emit a specific event here
executeTransferInternal(_from, _to, _value);
}
/**
* @dev calculates the balance of the user, which is the
* principal balance + interest generated by the principal balance + interest generated by the redirected balance
* @param _user the user for which the balance is being calculated
* @return the total balance of the user
**/
function balanceOf(address _user) public view returns(uint256) {
//current principal balance of the user
uint256 currentPrincipalBalance = super.balanceOf(_user);
//balance redirected by other users to _user for interest rate accrual
uint256 redirectedBalance = redirectedBalances[_user];
if(currentPrincipalBalance == 0 && redirectedBalance == 0){
return 0;
}
//if the _user is not redirecting the interest to anybody, accrues
//the interest for himself
if(interestRedirectionAddresses[_user] == address(0)){
//accruing for himself means that both the principal balance and
//the redirected balance partecipate in the interest
return calculateCumulatedBalanceInternal(
_user,
currentPrincipalBalance.add(redirectedBalance)
)
.sub(redirectedBalance);
}
else {
//if the user redirected the interest, then only the redirected
//balance generates interest. In that case, the interest generated
//by the redirected balance is added to the current principal balance.
return currentPrincipalBalance.add(
calculateCumulatedBalanceInternal(
_user,
redirectedBalance
)
.sub(redirectedBalance)
);
}
}
/**
* @dev returns the principal balance of the user. The principal balance is the last
* updated stored balance, which does not consider the perpetually accruing interest.
* @param _user the address of the user
* @return the principal balance of the user
**/
function principalBalanceOf(address _user) external view returns(uint256) {
return super.balanceOf(_user);
}
/**
* @dev calculates the total supply of the specific aToken
* since the balance of every single user increases over time, the total supply
* does that too.
* @return the current total supply
**/
function totalSupply() public view returns(uint256) {
uint256 currentSupplyPrincipal = super.totalSupply();
if(currentSupplyPrincipal == 0){
return 0;
}
return currentSupplyPrincipal
.wadToRay()
.rayMul(core.getReserveNormalizedIncome(underlyingAssetAddress))
.rayToWad();
}
/**
* @dev Used to validate transfers before actually executing them.
* @param _user address of the user to check
* @param _amount the amount to check
* @return true if the _user can transfer _amount, false otherwise
**/
function isTransferAllowed(address _user, uint256 _amount) public view returns (bool) {
return dataProvider.balanceDecreaseAllowed(underlyingAssetAddress, _user, _amount);
}
/**
* @dev returns the last index of the user, used to calculate the balance of the user
* @param _user address of the user
* @return the last user index
**/
function getUserIndex(address _user) external view returns(uint256) {
return userIndexes[_user];
}
/**
* @dev returns the address to which the interest is redirected
* @param _user address of the user
* @return 0 if there is no redirection, an address otherwise
**/
function getInterestRedirectionAddress(address _user) external view returns(address) {
return interestRedirectionAddresses[_user];
}
/**
* @dev returns the redirected balance of the user. The redirected balance is the balance
* redirected by other accounts to the user, that is accrueing interest for him.
* @param _user address of the user
* @return the total redirected balance
**/
function getRedirectedBalance(address _user) external view returns(uint256) {
return redirectedBalances[_user];
}
/**
* @dev accumulates the accrued interest of the user to the principal balance
* @param _user the address of the user for which the interest is being accumulated
* @return the previous principal balance, the new principal balance, the balance increase
* and the new user index
**/
function cumulateBalanceInternal(address _user)
internal
returns(uint256, uint256, uint256, uint256) {
uint256 previousPrincipalBalance = super.balanceOf(_user);
//calculate the accrued interest since the last accumulation
uint256 balanceIncrease = balanceOf(_user).sub(previousPrincipalBalance);
//mints an amount of tokens equivalent to the amount accumulated
_mint(_user, balanceIncrease);
//updates the user index
uint256 index = userIndexes[_user] = core.getReserveNormalizedIncome(underlyingAssetAddress);
return (
previousPrincipalBalance,
previousPrincipalBalance.add(balanceIncrease),
balanceIncrease,
index
);
}
/**
* @dev updates the redirected balance of the user. If the user is not redirecting his
* interest, nothing is executed.
* @param _user the address of the user for which the interest is being accumulated
* @param _balanceToAdd the amount to add to the redirected balance
* @param _balanceToRemove the amount to remove from the redirected balance
**/
function updateRedirectedBalanceOfRedirectionAddressInternal(
address _user,
uint256 _balanceToAdd,
uint256 _balanceToRemove
) internal {
address redirectionAddress = interestRedirectionAddresses[_user];
//if there isn't any redirection, nothing to be done
if(redirectionAddress == address(0)){
return;
}
//compound balances of the redirected address
(,,uint256 balanceIncrease, uint256 index) = cumulateBalanceInternal(redirectionAddress);
//updating the redirected balance
redirectedBalances[redirectionAddress] = redirectedBalances[redirectionAddress]
.add(_balanceToAdd)
.sub(_balanceToRemove);
//if the interest of redirectionAddress is also being redirected, we need to update
//the redirected balance of the redirection target by adding the balance increase
address targetOfRedirectionAddress = interestRedirectionAddresses[redirectionAddress];
if(targetOfRedirectionAddress != address(0)){
redirectedBalances[targetOfRedirectionAddress] = redirectedBalances[targetOfRedirectionAddress].add(balanceIncrease);
}
emit RedirectedBalanceUpdated(
redirectionAddress,
balanceIncrease,
index,
_balanceToAdd,
_balanceToRemove
);
}
/**
* @dev calculate the interest accrued by _user on a specific balance
* @param _user the address of the user for which the interest is being accumulated
* @param _balance the balance on which the interest is calculated
* @return the interest rate accrued
**/
function calculateCumulatedBalanceInternal(
address _user,
uint256 _balance
) internal view returns (uint256) {
return _balance
.wadToRay()
.rayMul(core.getReserveNormalizedIncome(underlyingAssetAddress))
.rayDiv(userIndexes[_user])
.rayToWad();
}
/**
* @dev executes the transfer of aTokens, invoked by both _transfer() and
* transferOnLiquidation()
* @param _from the address from which transfer the aTokens
* @param _to the destination address
* @param _value the amount to transfer
**/
function executeTransferInternal(
address _from,
address _to,
uint256 _value
) internal {
require(_value > 0, "Transferred amount needs to be greater than zero");
//cumulate the balance of the sender
(,
uint256 fromBalance,
uint256 fromBalanceIncrease,
uint256 fromIndex
) = cumulateBalanceInternal(_from);
//cumulate the balance of the receiver
(,
,
uint256 toBalanceIncrease,
uint256 toIndex
) = cumulateBalanceInternal(_to);
//if the sender is redirecting his interest towards someone else,
//adds to the redirected balance the accrued interest and removes the amount
//being transferred
updateRedirectedBalanceOfRedirectionAddressInternal(_from, fromBalanceIncrease, _value);
//if the receiver is redirecting his interest towards someone else,
//adds to the redirected balance the accrued interest and the amount
//being transferred
updateRedirectedBalanceOfRedirectionAddressInternal(_to, toBalanceIncrease.add(_value), 0);
//performs the transfer
super._transfer(_from, _to, _value);
bool fromIndexReset = false;
//reset the user data if the remaining balance is 0
if(fromBalance.sub(_value) == 0){
fromIndexReset = resetDataOnZeroBalanceInternal(_from);
}
emit BalanceTransfer(
_from,
_to,
_value,
fromBalanceIncrease,
toBalanceIncrease,
fromIndexReset ? 0 : fromIndex,
toIndex
);
}
/**
* @dev executes the redirection of the interest from one address to another.
* immediately after redirection, the destination address will start to accrue interest.
* @param _from the address from which transfer the aTokens
* @param _to the destination address
**/
function redirectInterestStreamInternal(
address _from,
address _to
) internal {
address currentRedirectionAddress = interestRedirectionAddresses[_from];
require(_to != currentRedirectionAddress, "Interest is already redirected to the user");
//accumulates the accrued interest to the principal
(uint256 previousPrincipalBalance,
uint256 fromBalance,
uint256 balanceIncrease,
uint256 fromIndex) = cumulateBalanceInternal(_from);
require(fromBalance > 0, "Interest stream can only be redirected if there is a valid balance");
//if the user is already redirecting the interest to someone, before changing
//the redirection address we substract the redirected balance of the previous
//recipient
if(currentRedirectionAddress != address(0)){
updateRedirectedBalanceOfRedirectionAddressInternal(_from,0, previousPrincipalBalance);
}
//if the user is redirecting the interest back to himself,
//we simply set to 0 the interest redirection address
if(_to == _from) {
interestRedirectionAddresses[_from] = address(0);
emit InterestStreamRedirected(
_from,
address(0),
fromBalance,
balanceIncrease,
fromIndex
);
return;
}
//first set the redirection address to the new recipient
interestRedirectionAddresses[_from] = _to;
//adds the user balance to the redirected balance of the destination
updateRedirectedBalanceOfRedirectionAddressInternal(_from,fromBalance,0);
emit InterestStreamRedirected(
_from,
_to,
fromBalance,
balanceIncrease,
fromIndex
);
}
/**
* @dev function to reset the interest stream redirection and the user index, if the
* user has no balance left.
* @param _user the address of the user
* @return true if the user index has also been reset, false otherwise. useful to emit the proper user index value
**/
function resetDataOnZeroBalanceInternal(address _user) internal returns(bool) {
//if the user has 0 principal balance, the interest stream redirection gets reset
interestRedirectionAddresses[_user] = address(0);
//emits a InterestStreamRedirected event to notify that the redirection has been reset
emit InterestStreamRedirected(_user, address(0),0,0,0);
//if the redirected balance is also 0, we clear up the user index
if(redirectedBalances[_user] == 0){
userIndexes[_user] = 0;
return true;
}
else{
return false;
}
}
}
/**
* @title IFlashLoanReceiver interface
* @notice Interface for the Aave fee IFlashLoanReceiver.
* @author Aave
* @dev implement this interface to develop a flashloan-compatible flashLoanReceiver contract
**/
interface IFlashLoanReceiver {
function executeOperation(address _reserve, uint256 _amount, uint256 _fee, bytes calldata _params) external;
}
/**
* @title ILendingRateOracle interface
* @notice Interface for the Aave borrow rate oracle. Provides the average market borrow rate to be used as a base for the stable borrow rate calculations
**/
interface ILendingRateOracle {
/**
@dev returns the market borrow rate in ray
**/
function getMarketBorrowRate(address _asset) external view returns (uint256);
/**
@dev sets the market borrow rate. Rate value must be in ray
**/
function setMarketBorrowRate(address _asset, uint256 _rate) external;
}
/**
@title IReserveInterestRateStrategyInterface interface
@notice Interface for the calculation of the interest rates.
*/
interface IReserveInterestRateStrategy {
/**
* @dev returns the base variable borrow rate, in rays
*/
function getBaseVariableBorrowRate() external view returns (uint256);
/**
* @dev calculates the liquidity, stable, and variable rates depending on the current utilization rate
* and the base parameters
*
*/
function calculateInterestRates(
address _reserve,
uint256 _utilizationRate,
uint256 _totalBorrowsStable,
uint256 _totalBorrowsVariable,
uint256 _averageStableBorrowRate)
external
view
returns (uint256 liquidityRate, uint256 stableBorrowRate, uint256 variableBorrowRate);
}
library EthAddressLib {
/**
* @dev returns the address used within the protocol to identify ETH
* @return the address assigned to ETH
*/
function ethAddress() internal pure returns(address) {
return 0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE;
}
}
/**
* @title LendingPoolCore contract
* @author Aave
* @notice Holds the state of the lending pool and all the funds deposited
* @dev NOTE: The core does not enforce security checks on the update of the state
* (eg, updateStateOnBorrow() does not enforce that borrowed is enabled on the reserve).
* The check that an action can be performed is a duty of the overlying LendingPool contract.
**/
contract LendingPoolCore is VersionedInitializable {
using SafeMath for uint256;
using WadRayMath for uint256;
using CoreLibrary for CoreLibrary.ReserveData;
using CoreLibrary for CoreLibrary.UserReserveData;
using SafeERC20 for ERC20;
using Address for address payable;
/**
* @dev Emitted when the state of a reserve is updated
* @param reserve the address of the reserve
* @param liquidityRate the new liquidity rate
* @param stableBorrowRate the new stable borrow rate
* @param variableBorrowRate the new variable borrow rate
* @param liquidityIndex the new liquidity index
* @param variableBorrowIndex the new variable borrow index
**/
event ReserveUpdated(
address indexed reserve,
uint256 liquidityRate,
uint256 stableBorrowRate,
uint256 variableBorrowRate,
uint256 liquidityIndex,
uint256 variableBorrowIndex
);
address public lendingPoolAddress;
LendingPoolAddressesProvider public addressesProvider;
/**
* @dev only lending pools can use functions affected by this modifier
**/
modifier onlyLendingPool {
require(lendingPoolAddress == msg.sender, "The caller must be a lending pool contract");
_;
}
/**
* @dev only lending pools configurator can use functions affected by this modifier
**/
modifier onlyLendingPoolConfigurator {
require(
addressesProvider.getLendingPoolConfigurator() == msg.sender,
"The caller must be a lending pool configurator contract"
);
_;
}
mapping(address => CoreLibrary.ReserveData) internal reserves;
mapping(address => mapping(address => CoreLibrary.UserReserveData)) internal usersReserveData;
address[] public reservesList;
uint256 public constant CORE_REVISION = 0x4;
/**
* @dev returns the revision number of the contract
**/
function getRevision() internal pure returns (uint256) {
return CORE_REVISION;
}
/**
* @dev initializes the Core contract, invoked upon registration on the AddressesProvider
* @param _addressesProvider the addressesProvider contract
**/
function initialize(LendingPoolAddressesProvider _addressesProvider) public initializer {
addressesProvider = _addressesProvider;
refreshConfigInternal();
}
/**
* @dev updates the state of the core as a result of a deposit action
* @param _reserve the address of the reserve in which the deposit is happening
* @param _user the address of the the user depositing
* @param _amount the amount being deposited
* @param _isFirstDeposit true if the user is depositing for the first time
**/
function updateStateOnDeposit(
address _reserve,
address _user,
uint256 _amount,
bool _isFirstDeposit
) external onlyLendingPool {
reserves[_reserve].updateCumulativeIndexes();
updateReserveInterestRatesAndTimestampInternal(_reserve, _amount, 0);
if (_isFirstDeposit) {
//if this is the first deposit of the user, we configure the deposit as enabled to be used as collateral
setUserUseReserveAsCollateral(_reserve, _user, true);
}
}
/**
* @dev updates the state of the core as a result of a redeem action
* @param _reserve the address of the reserve in which the redeem is happening
* @param _user the address of the the user redeeming
* @param _amountRedeemed the amount being redeemed
* @param _userRedeemedEverything true if the user is redeeming everything
**/
function updateStateOnRedeem(
address _reserve,
address _user,
uint256 _amountRedeemed,
bool _userRedeemedEverything
) external onlyLendingPool {
//compound liquidity and variable borrow interests
reserves[_reserve].updateCumulativeIndexes();
updateReserveInterestRatesAndTimestampInternal(_reserve, 0, _amountRedeemed);
//if user redeemed everything the useReserveAsCollateral flag is reset
if (_userRedeemedEverything) {
setUserUseReserveAsCollateral(_reserve, _user, false);
}
}
/**
* @dev updates the state of the core as a result of a flashloan action
* @param _reserve the address of the reserve in which the flashloan is happening
* @param _income the income of the protocol as a result of the action
**/
function updateStateOnFlashLoan(
address _reserve,
uint256 _availableLiquidityBefore,
uint256 _income,
uint256 _protocolFee
) external onlyLendingPool {
transferFlashLoanProtocolFeeInternal(_reserve, _protocolFee);
//compounding the cumulated interest
reserves[_reserve].updateCumulativeIndexes();
uint256 totalLiquidityBefore = _availableLiquidityBefore.add(
getReserveTotalBorrows(_reserve)
);
//compounding the received fee into the reserve
reserves[_reserve].cumulateToLiquidityIndex(totalLiquidityBefore, _income);
//refresh interest rates
updateReserveInterestRatesAndTimestampInternal(_reserve, _income, 0);
}
/**
* @dev updates the state of the core as a consequence of a borrow action.
* @param _reserve the address of the reserve on which the user is borrowing
* @param _user the address of the borrower
* @param _amountBorrowed the new amount borrowed
* @param _borrowFee the fee on the amount borrowed
* @param _rateMode the borrow rate mode (stable, variable)
* @return the new borrow rate for the user
**/
function updateStateOnBorrow(
address _reserve,
address _user,
uint256 _amountBorrowed,
uint256 _borrowFee,
CoreLibrary.InterestRateMode _rateMode
) external onlyLendingPool returns (uint256, uint256) {
// getting the previous borrow data of the user
(uint256 principalBorrowBalance, , uint256 balanceIncrease) = getUserBorrowBalances(
_reserve,
_user
);
updateReserveStateOnBorrowInternal(
_reserve,
_user,
principalBorrowBalance,
balanceIncrease,
_amountBorrowed,
_rateMode
);
updateUserStateOnBorrowInternal(
_reserve,
_user,
_amountBorrowed,
balanceIncrease,
_borrowFee,
_rateMode
);
updateReserveInterestRatesAndTimestampInternal(_reserve, 0, _amountBorrowed);
return (getUserCurrentBorrowRate(_reserve, _user), balanceIncrease);
}
/**
* @dev updates the state of the core as a consequence of a repay action.
* @param _reserve the address of the reserve on which the user is repaying
* @param _user the address of the borrower
* @param _paybackAmountMinusFees the amount being paid back minus fees
* @param _originationFeeRepaid the fee on the amount that is being repaid
* @param _balanceIncrease the accrued interest on the borrowed amount
* @param _repaidWholeLoan true if the user is repaying the whole loan
**/
function updateStateOnRepay(
address _reserve,
address _user,
uint256 _paybackAmountMinusFees,
uint256 _originationFeeRepaid,
uint256 _balanceIncrease,
bool _repaidWholeLoan
) external onlyLendingPool {
updateReserveStateOnRepayInternal(
_reserve,
_user,
_paybackAmountMinusFees,
_balanceIncrease
);
updateUserStateOnRepayInternal(
_reserve,
_user,
_paybackAmountMinusFees,
_originationFeeRepaid,
_balanceIncrease,
_repaidWholeLoan
);
updateReserveInterestRatesAndTimestampInternal(_reserve, _paybackAmountMinusFees, 0);
}
/**
* @dev updates the state of the core as a consequence of a swap rate action.
* @param _reserve the address of the reserve on which the user is repaying
* @param _user the address of the borrower
* @param _principalBorrowBalance the amount borrowed by the user
* @param _compoundedBorrowBalance the amount borrowed plus accrued interest
* @param _balanceIncrease the accrued interest on the borrowed amount
* @param _currentRateMode the current interest rate mode for the user
**/
function updateStateOnSwapRate(
address _reserve,
address _user,
uint256 _principalBorrowBalance,
uint256 _compoundedBorrowBalance,
uint256 _balanceIncrease,
CoreLibrary.InterestRateMode _currentRateMode
) external onlyLendingPool returns (CoreLibrary.InterestRateMode, uint256) {
updateReserveStateOnSwapRateInternal(
_reserve,
_user,
_principalBorrowBalance,
_compoundedBorrowBalance,
_currentRateMode
);
CoreLibrary.InterestRateMode newRateMode = updateUserStateOnSwapRateInternal(
_reserve,
_user,
_balanceIncrease,
_currentRateMode
);
updateReserveInterestRatesAndTimestampInternal(_reserve, 0, 0);
return (newRateMode, getUserCurrentBorrowRate(_reserve, _user));
}
/**
* @dev updates the state of the core as a consequence of a liquidation action.
* @param _principalReserve the address of the principal reserve that is being repaid
* @param _collateralReserve the address of the collateral reserve that is being liquidated
* @param _user the address of the borrower
* @param _amountToLiquidate the amount being repaid by the liquidator
* @param _collateralToLiquidate the amount of collateral being liquidated
* @param _feeLiquidated the amount of origination fee being liquidated
* @param _liquidatedCollateralForFee the amount of collateral equivalent to the origination fee + bonus
* @param _balanceIncrease the accrued interest on the borrowed amount
* @param _liquidatorReceivesAToken true if the liquidator will receive aTokens, false otherwise
**/
function updateStateOnLiquidation(
address _principalReserve,
address _collateralReserve,
address _user,
uint256 _amountToLiquidate,
uint256 _collateralToLiquidate,
uint256 _feeLiquidated,
uint256 _liquidatedCollateralForFee,
uint256 _balanceIncrease,
bool _liquidatorReceivesAToken
) external onlyLendingPool {
updatePrincipalReserveStateOnLiquidationInternal(
_principalReserve,
_user,
_amountToLiquidate,
_balanceIncrease
);
updateCollateralReserveStateOnLiquidationInternal(
_collateralReserve
);
updateUserStateOnLiquidationInternal(
_principalReserve,
_user,
_amountToLiquidate,
_feeLiquidated,
_balanceIncrease
);
updateReserveInterestRatesAndTimestampInternal(_principalReserve, _amountToLiquidate, 0);
if (!_liquidatorReceivesAToken) {
updateReserveInterestRatesAndTimestampInternal(
_collateralReserve,
0,
_collateralToLiquidate.add(_liquidatedCollateralForFee)
);
}
}
/**
* @dev updates the state of the core as a consequence of a stable rate rebalance
* @param _reserve the address of the principal reserve where the user borrowed
* @param _user the address of the borrower
* @param _balanceIncrease the accrued interest on the borrowed amount
* @return the new stable rate for the user
**/
function updateStateOnRebalance(address _reserve, address _user, uint256 _balanceIncrease)
external
onlyLendingPool
returns (uint256)
{
updateReserveStateOnRebalanceInternal(_reserve, _user, _balanceIncrease);
//update user data and rebalance the rate
updateUserStateOnRebalanceInternal(_reserve, _user, _balanceIncrease);
updateReserveInterestRatesAndTimestampInternal(_reserve, 0, 0);
return usersReserveData[_user][_reserve].stableBorrowRate;
}
/**
* @dev enables or disables a reserve as collateral
* @param _reserve the address of the principal reserve where the user deposited
* @param _user the address of the depositor
* @param _useAsCollateral true if the depositor wants to use the reserve as collateral
**/
function setUserUseReserveAsCollateral(address _reserve, address _user, bool _useAsCollateral)
public
onlyLendingPool
{
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
user.useAsCollateral = _useAsCollateral;
}
/**
* @notice ETH/token transfer functions
**/
/**
* @dev fallback function enforces that the caller is a contract, to support flashloan transfers
**/
function() external payable {
//only contracts can send ETH to the core
require(msg.sender.isContract(), "Only contracts can send ether to the Lending pool core");
}
/**
* @dev transfers to the user a specific amount from the reserve.
* @param _reserve the address of the reserve where the transfer is happening
* @param _user the address of the user receiving the transfer
* @param _amount the amount being transferred
**/
function transferToUser(address _reserve, address payable _user, uint256 _amount)
external
onlyLendingPool
{
if (_reserve != EthAddressLib.ethAddress()) {
ERC20(_reserve).safeTransfer(_user, _amount);
} else {
//solium-disable-next-line
(bool result, ) = _user.call.value(_amount).gas(50000)("");
require(result, "Transfer of ETH failed");
}
}
/**
* @dev transfers the protocol fees to the fees collection address
* @param _token the address of the token being transferred
* @param _user the address of the user from where the transfer is happening
* @param _amount the amount being transferred
* @param _destination the fee receiver address
**/
function transferToFeeCollectionAddress(
address _token,
address _user,
uint256 _amount,
address _destination
) external payable onlyLendingPool {
address payable feeAddress = address(uint160(_destination)); //cast the address to payable
if (_token != EthAddressLib.ethAddress()) {
require(
msg.value == 0,
"User is sending ETH along with the ERC20 transfer. Check the value attribute of the transaction"
);
ERC20(_token).safeTransferFrom(_user, feeAddress, _amount);
} else {
require(msg.value >= _amount, "The amount and the value sent to deposit do not match");
//solium-disable-next-line
(bool result, ) = feeAddress.call.value(_amount).gas(50000)("");
require(result, "Transfer of ETH failed");
}
}
/**
* @dev transfers the fees to the fees collection address in the case of liquidation
* @param _token the address of the token being transferred
* @param _amount the amount being transferred
* @param _destination the fee receiver address
**/
function liquidateFee(
address _token,
uint256 _amount,
address _destination
) external payable onlyLendingPool {
address payable feeAddress = address(uint160(_destination)); //cast the address to payable
require(
msg.value == 0,
"Fee liquidation does not require any transfer of value"
);
if (_token != EthAddressLib.ethAddress()) {
ERC20(_token).safeTransfer(feeAddress, _amount);
} else {
//solium-disable-next-line
(bool result, ) = feeAddress.call.value(_amount).gas(50000)("");
require(result, "Transfer of ETH failed");
}
}
/**
* @dev transfers an amount from a user to the destination reserve
* @param _reserve the address of the reserve where the amount is being transferred
* @param _user the address of the user from where the transfer is happening
* @param _amount the amount being transferred
**/
function transferToReserve(address _reserve, address payable _user, uint256 _amount)
external
payable
onlyLendingPool
{
if (_reserve != EthAddressLib.ethAddress()) {
require(msg.value == 0, "User is sending ETH along with the ERC20 transfer.");
ERC20(_reserve).safeTransferFrom(_user, address(this), _amount);
} else {
require(msg.value >= _amount, "The amount and the value sent to deposit do not match");
if (msg.value > _amount) {
//send back excess ETH
uint256 excessAmount = msg.value.sub(_amount);
//solium-disable-next-line
(bool result, ) = _user.call.value(excessAmount).gas(50000)("");
require(result, "Transfer of ETH failed");
}
}
}
/**
* @notice data access functions
**/
/**
* @dev returns the basic data (balances, fee accrued, reserve enabled/disabled as collateral)
* needed to calculate the global account data in the LendingPoolDataProvider
* @param _reserve the address of the reserve
* @param _user the address of the user
* @return the user deposited balance, the principal borrow balance, the fee, and if the reserve is enabled as collateral or not
**/
function getUserBasicReserveData(address _reserve, address _user)
external
view
returns (uint256, uint256, uint256, bool)
{
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
uint256 underlyingBalance = getUserUnderlyingAssetBalance(_reserve, _user);
if (user.principalBorrowBalance == 0) {
return (underlyingBalance, 0, 0, user.useAsCollateral);
}
return (
underlyingBalance,
user.getCompoundedBorrowBalance(reserve),
user.originationFee,
user.useAsCollateral
);
}
/**
* @dev checks if a user is allowed to borrow at a stable rate
* @param _reserve the reserve address
* @param _user the user
* @param _amount the amount the the user wants to borrow
* @return true if the user is allowed to borrow at a stable rate, false otherwise
**/
function isUserAllowedToBorrowAtStable(address _reserve, address _user, uint256 _amount)
external
view
returns (bool)
{
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
if (!reserve.isStableBorrowRateEnabled) return false;
return
!user.useAsCollateral ||
!reserve.usageAsCollateralEnabled ||
_amount > getUserUnderlyingAssetBalance(_reserve, _user);
}
/**
* @dev gets the underlying asset balance of a user based on the corresponding aToken balance.
* @param _reserve the reserve address
* @param _user the user address
* @return the underlying deposit balance of the user
**/
function getUserUnderlyingAssetBalance(address _reserve, address _user)
public
view
returns (uint256)
{
AToken aToken = AToken(reserves[_reserve].aTokenAddress);
return aToken.balanceOf(_user);
}
/**
* @dev gets the interest rate strategy contract address for the reserve
* @param _reserve the reserve address
* @return the address of the interest rate strategy contract
**/
function getReserveInterestRateStrategyAddress(address _reserve) public view returns (address) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.interestRateStrategyAddress;
}
/**
* @dev gets the aToken contract address for the reserve
* @param _reserve the reserve address
* @return the address of the aToken contract
**/
function getReserveATokenAddress(address _reserve) public view returns (address) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.aTokenAddress;
}
/**
* @dev gets the available liquidity in the reserve. The available liquidity is the balance of the core contract
* @param _reserve the reserve address
* @return the available liquidity
**/
function getReserveAvailableLiquidity(address _reserve) public view returns (uint256) {
uint256 balance = 0;
if (_reserve == EthAddressLib.ethAddress()) {
balance = address(this).balance;
} else {
balance = IERC20(_reserve).balanceOf(address(this));
}
return balance;
}
/**
* @dev gets the total liquidity in the reserve. The total liquidity is the balance of the core contract + total borrows
* @param _reserve the reserve address
* @return the total liquidity
**/
function getReserveTotalLiquidity(address _reserve) public view returns (uint256) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return getReserveAvailableLiquidity(_reserve).add(reserve.getTotalBorrows());
}
/**
* @dev gets the normalized income of the reserve. a value of 1e27 means there is no income. A value of 2e27 means there
* there has been 100% income.
* @param _reserve the reserve address
* @return the reserve normalized income
**/
function getReserveNormalizedIncome(address _reserve) external view returns (uint256) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.getNormalizedIncome();
}
/**
* @dev gets the reserve total borrows
* @param _reserve the reserve address
* @return the total borrows (stable + variable)
**/
function getReserveTotalBorrows(address _reserve) public view returns (uint256) {
return reserves[_reserve].getTotalBorrows();
}
/**
* @dev gets the reserve total borrows stable
* @param _reserve the reserve address
* @return the total borrows stable
**/
function getReserveTotalBorrowsStable(address _reserve) external view returns (uint256) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.totalBorrowsStable;
}
/**
* @dev gets the reserve total borrows variable
* @param _reserve the reserve address
* @return the total borrows variable
**/
function getReserveTotalBorrowsVariable(address _reserve) external view returns (uint256) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.totalBorrowsVariable;
}
/**
* @dev gets the reserve liquidation threshold
* @param _reserve the reserve address
* @return the reserve liquidation threshold
**/
function getReserveLiquidationThreshold(address _reserve) external view returns (uint256) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.liquidationThreshold;
}
/**
* @dev gets the reserve liquidation bonus
* @param _reserve the reserve address
* @return the reserve liquidation bonus
**/
function getReserveLiquidationBonus(address _reserve) external view returns (uint256) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.liquidationBonus;
}
/**
* @dev gets the reserve current variable borrow rate. Is the base variable borrow rate if the reserve is empty
* @param _reserve the reserve address
* @return the reserve current variable borrow rate
**/
function getReserveCurrentVariableBorrowRate(address _reserve) external view returns (uint256) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
if (reserve.currentVariableBorrowRate == 0) {
return
IReserveInterestRateStrategy(reserve.interestRateStrategyAddress)
.getBaseVariableBorrowRate();
}
return reserve.currentVariableBorrowRate;
}
/**
* @dev gets the reserve current stable borrow rate. Is the market rate if the reserve is empty
* @param _reserve the reserve address
* @return the reserve current stable borrow rate
**/
function getReserveCurrentStableBorrowRate(address _reserve) public view returns (uint256) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
ILendingRateOracle oracle = ILendingRateOracle(addressesProvider.getLendingRateOracle());
if (reserve.currentStableBorrowRate == 0) {
//no stable rate borrows yet
return oracle.getMarketBorrowRate(_reserve);
}
return reserve.currentStableBorrowRate;
}
/**
* @dev gets the reserve average stable borrow rate. The average stable rate is the weighted average
* of all the loans taken at stable rate.
* @param _reserve the reserve address
* @return the reserve current average borrow rate
**/
function getReserveCurrentAverageStableBorrowRate(address _reserve)
external
view
returns (uint256)
{
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.currentAverageStableBorrowRate;
}
/**
* @dev gets the reserve liquidity rate
* @param _reserve the reserve address
* @return the reserve liquidity rate
**/
function getReserveCurrentLiquidityRate(address _reserve) external view returns (uint256) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.currentLiquidityRate;
}
/**
* @dev gets the reserve liquidity cumulative index
* @param _reserve the reserve address
* @return the reserve liquidity cumulative index
**/
function getReserveLiquidityCumulativeIndex(address _reserve) external view returns (uint256) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.lastLiquidityCumulativeIndex;
}
/**
* @dev gets the reserve variable borrow index
* @param _reserve the reserve address
* @return the reserve variable borrow index
**/
function getReserveVariableBorrowsCumulativeIndex(address _reserve)
external
view
returns (uint256)
{
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.lastVariableBorrowCumulativeIndex;
}
/**
* @dev this function aggregates the configuration parameters of the reserve.
* It's used in the LendingPoolDataProvider specifically to save gas, and avoid
* multiple external contract calls to fetch the same data.
* @param _reserve the reserve address
* @return the reserve decimals
* @return the base ltv as collateral
* @return the liquidation threshold
* @return if the reserve is used as collateral or not
**/
function getReserveConfiguration(address _reserve)
external
view
returns (uint256, uint256, uint256, bool)
{
uint256 decimals;
uint256 baseLTVasCollateral;
uint256 liquidationThreshold;
bool usageAsCollateralEnabled;
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
decimals = reserve.decimals;
baseLTVasCollateral = reserve.baseLTVasCollateral;
liquidationThreshold = reserve.liquidationThreshold;
usageAsCollateralEnabled = reserve.usageAsCollateralEnabled;
return (decimals, baseLTVasCollateral, liquidationThreshold, usageAsCollateralEnabled);
}
/**
* @dev returns the decimals of the reserve
* @param _reserve the reserve address
* @return the reserve decimals
**/
function getReserveDecimals(address _reserve) external view returns (uint256) {
return reserves[_reserve].decimals;
}
/**
* @dev returns true if the reserve is enabled for borrowing
* @param _reserve the reserve address
* @return true if the reserve is enabled for borrowing, false otherwise
**/
function isReserveBorrowingEnabled(address _reserve) external view returns (bool) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.borrowingEnabled;
}
/**
* @dev returns true if the reserve is enabled as collateral
* @param _reserve the reserve address
* @return true if the reserve is enabled as collateral, false otherwise
**/
function isReserveUsageAsCollateralEnabled(address _reserve) external view returns (bool) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.usageAsCollateralEnabled;
}
/**
* @dev returns true if the stable rate is enabled on reserve
* @param _reserve the reserve address
* @return true if the stable rate is enabled on reserve, false otherwise
**/
function getReserveIsStableBorrowRateEnabled(address _reserve) external view returns (bool) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.isStableBorrowRateEnabled;
}
/**
* @dev returns true if the reserve is active
* @param _reserve the reserve address
* @return true if the reserve is active, false otherwise
**/
function getReserveIsActive(address _reserve) external view returns (bool) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.isActive;
}
/**
* @notice returns if a reserve is freezed
* @param _reserve the reserve for which the information is needed
* @return true if the reserve is freezed, false otherwise
**/
function getReserveIsFreezed(address _reserve) external view returns (bool) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
return reserve.isFreezed;
}
/**
* @notice returns the timestamp of the last action on the reserve
* @param _reserve the reserve for which the information is needed
* @return the last updated timestamp of the reserve
**/
function getReserveLastUpdate(address _reserve) external view returns (uint40 timestamp) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
timestamp = reserve.lastUpdateTimestamp;
}
/**
* @dev returns the utilization rate U of a specific reserve
* @param _reserve the reserve for which the information is needed
* @return the utilization rate in ray
**/
function getReserveUtilizationRate(address _reserve) public view returns (uint256) {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
uint256 totalBorrows = reserve.getTotalBorrows();
if (totalBorrows == 0) {
return 0;
}
uint256 availableLiquidity = getReserveAvailableLiquidity(_reserve);
return totalBorrows.rayDiv(availableLiquidity.add(totalBorrows));
}
/**
* @return the array of reserves configured on the core
**/
function getReserves() external view returns (address[] memory) {
return reservesList;
}
/**
* @param _reserve the address of the reserve for which the information is needed
* @param _user the address of the user for which the information is needed
* @return true if the user has chosen to use the reserve as collateral, false otherwise
**/
function isUserUseReserveAsCollateralEnabled(address _reserve, address _user)
external
view
returns (bool)
{
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
return user.useAsCollateral;
}
/**
* @param _reserve the address of the reserve for which the information is needed
* @param _user the address of the user for which the information is needed
* @return the origination fee for the user
**/
function getUserOriginationFee(address _reserve, address _user)
external
view
returns (uint256)
{
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
return user.originationFee;
}
/**
* @dev users with no loans in progress have NONE as borrow rate mode
* @param _reserve the address of the reserve for which the information is needed
* @param _user the address of the user for which the information is needed
* @return the borrow rate mode for the user,
**/
function getUserCurrentBorrowRateMode(address _reserve, address _user)
public
view
returns (CoreLibrary.InterestRateMode)
{
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
if (user.principalBorrowBalance == 0) {
return CoreLibrary.InterestRateMode.NONE;
}
return
user.stableBorrowRate > 0
? CoreLibrary.InterestRateMode.STABLE
: CoreLibrary.InterestRateMode.VARIABLE;
}
/**
* @dev gets the current borrow rate of the user
* @param _reserve the address of the reserve for which the information is needed
* @param _user the address of the user for which the information is needed
* @return the borrow rate for the user,
**/
function getUserCurrentBorrowRate(address _reserve, address _user)
internal
view
returns (uint256)
{
CoreLibrary.InterestRateMode rateMode = getUserCurrentBorrowRateMode(_reserve, _user);
if (rateMode == CoreLibrary.InterestRateMode.NONE) {
return 0;
}
return
rateMode == CoreLibrary.InterestRateMode.STABLE
? usersReserveData[_user][_reserve].stableBorrowRate
: reserves[_reserve].currentVariableBorrowRate;
}
/**
* @dev the stable rate returned is 0 if the user is borrowing at variable or not borrowing at all
* @param _reserve the address of the reserve for which the information is needed
* @param _user the address of the user for which the information is needed
* @return the user stable rate
**/
function getUserCurrentStableBorrowRate(address _reserve, address _user)
external
view
returns (uint256)
{
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
return user.stableBorrowRate;
}
/**
* @dev calculates and returns the borrow balances of the user
* @param _reserve the address of the reserve
* @param _user the address of the user
* @return the principal borrow balance, the compounded balance and the balance increase since the last borrow/repay/swap/rebalance
**/
function getUserBorrowBalances(address _reserve, address _user)
public
view
returns (uint256, uint256, uint256)
{
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
if (user.principalBorrowBalance == 0) {
return (0, 0, 0);
}
uint256 principal = user.principalBorrowBalance;
uint256 compoundedBalance = CoreLibrary.getCompoundedBorrowBalance(
user,
reserves[_reserve]
);
return (principal, compoundedBalance, compoundedBalance.sub(principal));
}
/**
* @dev the variable borrow index of the user is 0 if the user is not borrowing or borrowing at stable
* @param _reserve the address of the reserve for which the information is needed
* @param _user the address of the user for which the information is needed
* @return the variable borrow index for the user
**/
function getUserVariableBorrowCumulativeIndex(address _reserve, address _user)
external
view
returns (uint256)
{
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
return user.lastVariableBorrowCumulativeIndex;
}
/**
* @dev the variable borrow index of the user is 0 if the user is not borrowing or borrowing at stable
* @param _reserve the address of the reserve for which the information is needed
* @param _user the address of the user for which the information is needed
* @return the variable borrow index for the user
**/
function getUserLastUpdate(address _reserve, address _user)
external
view
returns (uint256 timestamp)
{
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
timestamp = user.lastUpdateTimestamp;
}
/**
* @dev updates the lending pool core configuration
**/
function refreshConfiguration() external onlyLendingPoolConfigurator {
refreshConfigInternal();
}
/**
* @dev initializes a reserve
* @param _reserve the address of the reserve
* @param _aTokenAddress the address of the overlying aToken contract
* @param _decimals the decimals of the reserve currency
* @param _interestRateStrategyAddress the address of the interest rate strategy contract
**/
function initReserve(
address _reserve,
address _aTokenAddress,
uint256 _decimals,
address _interestRateStrategyAddress
) external onlyLendingPoolConfigurator {
reserves[_reserve].init(_aTokenAddress, _decimals, _interestRateStrategyAddress);
addReserveToListInternal(_reserve);
}
/**
* @dev removes the last added reserve in the reservesList array
* @param _reserveToRemove the address of the reserve
**/
function removeLastAddedReserve(address _reserveToRemove)
external onlyLendingPoolConfigurator {
address lastReserve = reservesList[reservesList.length-1];
require(lastReserve == _reserveToRemove, "Reserve being removed is different than the reserve requested");
//as we can't check if totalLiquidity is 0 (since the reserve added might not be an ERC20) we at least check that there is nothing borrowed
require(getReserveTotalBorrows(lastReserve) == 0, "Cannot remove a reserve with liquidity deposited");
reserves[lastReserve].isActive = false;
reserves[lastReserve].aTokenAddress = address(0);
reserves[lastReserve].decimals = 0;
reserves[lastReserve].lastLiquidityCumulativeIndex = 0;
reserves[lastReserve].lastVariableBorrowCumulativeIndex = 0;
reserves[lastReserve].borrowingEnabled = false;
reserves[lastReserve].usageAsCollateralEnabled = false;
reserves[lastReserve].baseLTVasCollateral = 0;
reserves[lastReserve].liquidationThreshold = 0;
reserves[lastReserve].liquidationBonus = 0;
reserves[lastReserve].interestRateStrategyAddress = address(0);
reservesList.pop();
}
/**
* @dev updates the address of the interest rate strategy contract
* @param _reserve the address of the reserve
* @param _rateStrategyAddress the address of the interest rate strategy contract
**/
function setReserveInterestRateStrategyAddress(address _reserve, address _rateStrategyAddress)
external
onlyLendingPoolConfigurator
{
reserves[_reserve].interestRateStrategyAddress = _rateStrategyAddress;
}
/**
* @dev enables borrowing on a reserve. Also sets the stable rate borrowing
* @param _reserve the address of the reserve
* @param _stableBorrowRateEnabled true if the stable rate needs to be enabled, false otherwise
**/
function enableBorrowingOnReserve(address _reserve, bool _stableBorrowRateEnabled)
external
onlyLendingPoolConfigurator
{
reserves[_reserve].enableBorrowing(_stableBorrowRateEnabled);
}
/**
* @dev disables borrowing on a reserve
* @param _reserve the address of the reserve
**/
function disableBorrowingOnReserve(address _reserve) external onlyLendingPoolConfigurator {
reserves[_reserve].disableBorrowing();
}
/**
* @dev enables a reserve to be used as collateral
* @param _reserve the address of the reserve
**/
function enableReserveAsCollateral(
address _reserve,
uint256 _baseLTVasCollateral,
uint256 _liquidationThreshold,
uint256 _liquidationBonus
) external onlyLendingPoolConfigurator {
reserves[_reserve].enableAsCollateral(
_baseLTVasCollateral,
_liquidationThreshold,
_liquidationBonus
);
}
/**
* @dev disables a reserve to be used as collateral
* @param _reserve the address of the reserve
**/
function disableReserveAsCollateral(address _reserve) external onlyLendingPoolConfigurator {
reserves[_reserve].disableAsCollateral();
}
/**
* @dev enable the stable borrow rate mode on a reserve
* @param _reserve the address of the reserve
**/
function enableReserveStableBorrowRate(address _reserve) external onlyLendingPoolConfigurator {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
reserve.isStableBorrowRateEnabled = true;
}
/**
* @dev disable the stable borrow rate mode on a reserve
* @param _reserve the address of the reserve
**/
function disableReserveStableBorrowRate(address _reserve) external onlyLendingPoolConfigurator {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
reserve.isStableBorrowRateEnabled = false;
}
/**
* @dev activates a reserve
* @param _reserve the address of the reserve
**/
function activateReserve(address _reserve) external onlyLendingPoolConfigurator {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
require(
reserve.lastLiquidityCumulativeIndex > 0 &&
reserve.lastVariableBorrowCumulativeIndex > 0,
"Reserve has not been initialized yet"
);
reserve.isActive = true;
}
/**
* @dev deactivates a reserve
* @param _reserve the address of the reserve
**/
function deactivateReserve(address _reserve) external onlyLendingPoolConfigurator {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
reserve.isActive = false;
}
/**
* @notice allows the configurator to freeze the reserve.
* A freezed reserve does not allow any action apart from repay, redeem, liquidationCall, rebalance.
* @param _reserve the address of the reserve
**/
function freezeReserve(address _reserve) external onlyLendingPoolConfigurator {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
reserve.isFreezed = true;
}
/**
* @notice allows the configurator to unfreeze the reserve. A unfreezed reserve allows any action to be executed.
* @param _reserve the address of the reserve
**/
function unfreezeReserve(address _reserve) external onlyLendingPoolConfigurator {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
reserve.isFreezed = false;
}
/**
* @notice allows the configurator to update the loan to value of a reserve
* @param _reserve the address of the reserve
* @param _ltv the new loan to value
**/
function setReserveBaseLTVasCollateral(address _reserve, uint256 _ltv)
external
onlyLendingPoolConfigurator
{
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
reserve.baseLTVasCollateral = _ltv;
}
/**
* @notice allows the configurator to update the liquidation threshold of a reserve
* @param _reserve the address of the reserve
* @param _threshold the new liquidation threshold
**/
function setReserveLiquidationThreshold(address _reserve, uint256 _threshold)
external
onlyLendingPoolConfigurator
{
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
reserve.liquidationThreshold = _threshold;
}
/**
* @notice allows the configurator to update the liquidation bonus of a reserve
* @param _reserve the address of the reserve
* @param _bonus the new liquidation bonus
**/
function setReserveLiquidationBonus(address _reserve, uint256 _bonus)
external
onlyLendingPoolConfigurator
{
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
reserve.liquidationBonus = _bonus;
}
/**
* @notice allows the configurator to update the reserve decimals
* @param _reserve the address of the reserve
* @param _decimals the decimals of the reserve
**/
function setReserveDecimals(address _reserve, uint256 _decimals)
external
onlyLendingPoolConfigurator
{
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
reserve.decimals = _decimals;
}
/**
* @notice internal functions
**/
/**
* @dev updates the state of a reserve as a consequence of a borrow action.
* @param _reserve the address of the reserve on which the user is borrowing
* @param _user the address of the borrower
* @param _principalBorrowBalance the previous borrow balance of the borrower before the action
* @param _balanceIncrease the accrued interest of the user on the previous borrowed amount
* @param _amountBorrowed the new amount borrowed
* @param _rateMode the borrow rate mode (stable, variable)
**/
function updateReserveStateOnBorrowInternal(
address _reserve,
address _user,
uint256 _principalBorrowBalance,
uint256 _balanceIncrease,
uint256 _amountBorrowed,
CoreLibrary.InterestRateMode _rateMode
) internal {
reserves[_reserve].updateCumulativeIndexes();
//increasing reserve total borrows to account for the new borrow balance of the user
//NOTE: Depending on the previous borrow mode, the borrows might need to be switched from variable to stable or vice versa
updateReserveTotalBorrowsByRateModeInternal(
_reserve,
_user,
_principalBorrowBalance,
_balanceIncrease,
_amountBorrowed,
_rateMode
);
}
/**
* @dev updates the state of a user as a consequence of a borrow action.
* @param _reserve the address of the reserve on which the user is borrowing
* @param _user the address of the borrower
* @param _amountBorrowed the amount borrowed
* @param _balanceIncrease the accrued interest of the user on the previous borrowed amount
* @param _rateMode the borrow rate mode (stable, variable)
* @return the final borrow rate for the user. Emitted by the borrow() event
**/
function updateUserStateOnBorrowInternal(
address _reserve,
address _user,
uint256 _amountBorrowed,
uint256 _balanceIncrease,
uint256 _fee,
CoreLibrary.InterestRateMode _rateMode
) internal {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
if (_rateMode == CoreLibrary.InterestRateMode.STABLE) {
//stable
//reset the user variable index, and update the stable rate
user.stableBorrowRate = reserve.currentStableBorrowRate;
user.lastVariableBorrowCumulativeIndex = 0;
} else if (_rateMode == CoreLibrary.InterestRateMode.VARIABLE) {
//variable
//reset the user stable rate, and store the new borrow index
user.stableBorrowRate = 0;
user.lastVariableBorrowCumulativeIndex = reserve.lastVariableBorrowCumulativeIndex;
} else {
revert("Invalid borrow rate mode");
}
//increase the principal borrows and the origination fee
user.principalBorrowBalance = user.principalBorrowBalance.add(_amountBorrowed).add(
_balanceIncrease
);
user.originationFee = user.originationFee.add(_fee);
//solium-disable-next-line
user.lastUpdateTimestamp = uint40(block.timestamp);
}
/**
* @dev updates the state of the reserve as a consequence of a repay action.
* @param _reserve the address of the reserve on which the user is repaying
* @param _user the address of the borrower
* @param _paybackAmountMinusFees the amount being paid back minus fees
* @param _balanceIncrease the accrued interest on the borrowed amount
**/
function updateReserveStateOnRepayInternal(
address _reserve,
address _user,
uint256 _paybackAmountMinusFees,
uint256 _balanceIncrease
) internal {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
CoreLibrary.UserReserveData storage user = usersReserveData[_reserve][_user];
CoreLibrary.InterestRateMode borrowRateMode = getUserCurrentBorrowRateMode(_reserve, _user);
//update the indexes
reserves[_reserve].updateCumulativeIndexes();
//compound the cumulated interest to the borrow balance and then subtracting the payback amount
if (borrowRateMode == CoreLibrary.InterestRateMode.STABLE) {
reserve.increaseTotalBorrowsStableAndUpdateAverageRate(
_balanceIncrease,
user.stableBorrowRate
);
reserve.decreaseTotalBorrowsStableAndUpdateAverageRate(
_paybackAmountMinusFees,
user.stableBorrowRate
);
} else {
reserve.increaseTotalBorrowsVariable(_balanceIncrease);
reserve.decreaseTotalBorrowsVariable(_paybackAmountMinusFees);
}
}
/**
* @dev updates the state of the user as a consequence of a repay action.
* @param _reserve the address of the reserve on which the user is repaying
* @param _user the address of the borrower
* @param _paybackAmountMinusFees the amount being paid back minus fees
* @param _originationFeeRepaid the fee on the amount that is being repaid
* @param _balanceIncrease the accrued interest on the borrowed amount
* @param _repaidWholeLoan true if the user is repaying the whole loan
**/
function updateUserStateOnRepayInternal(
address _reserve,
address _user,
uint256 _paybackAmountMinusFees,
uint256 _originationFeeRepaid,
uint256 _balanceIncrease,
bool _repaidWholeLoan
) internal {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
//update the user principal borrow balance, adding the cumulated interest and then subtracting the payback amount
user.principalBorrowBalance = user.principalBorrowBalance.add(_balanceIncrease).sub(
_paybackAmountMinusFees
);
user.lastVariableBorrowCumulativeIndex = reserve.lastVariableBorrowCumulativeIndex;
//if the balance decrease is equal to the previous principal (user is repaying the whole loan)
//and the rate mode is stable, we reset the interest rate mode of the user
if (_repaidWholeLoan) {
user.stableBorrowRate = 0;
user.lastVariableBorrowCumulativeIndex = 0;
}
user.originationFee = user.originationFee.sub(_originationFeeRepaid);
//solium-disable-next-line
user.lastUpdateTimestamp = uint40(block.timestamp);
}
/**
* @dev updates the state of the user as a consequence of a swap rate action.
* @param _reserve the address of the reserve on which the user is performing the rate swap
* @param _user the address of the borrower
* @param _principalBorrowBalance the the principal amount borrowed by the user
* @param _compoundedBorrowBalance the principal amount plus the accrued interest
* @param _currentRateMode the rate mode at which the user borrowed
**/
function updateReserveStateOnSwapRateInternal(
address _reserve,
address _user,
uint256 _principalBorrowBalance,
uint256 _compoundedBorrowBalance,
CoreLibrary.InterestRateMode _currentRateMode
) internal {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
//compounding reserve indexes
reserve.updateCumulativeIndexes();
if (_currentRateMode == CoreLibrary.InterestRateMode.STABLE) {
uint256 userCurrentStableRate = user.stableBorrowRate;
//swap to variable
reserve.decreaseTotalBorrowsStableAndUpdateAverageRate(
_principalBorrowBalance,
userCurrentStableRate
); //decreasing stable from old principal balance
reserve.increaseTotalBorrowsVariable(_compoundedBorrowBalance); //increase variable borrows
} else if (_currentRateMode == CoreLibrary.InterestRateMode.VARIABLE) {
//swap to stable
uint256 currentStableRate = reserve.currentStableBorrowRate;
reserve.decreaseTotalBorrowsVariable(_principalBorrowBalance);
reserve.increaseTotalBorrowsStableAndUpdateAverageRate(
_compoundedBorrowBalance,
currentStableRate
);
} else {
revert("Invalid rate mode received");
}
}
/**
* @dev updates the state of the user as a consequence of a swap rate action.
* @param _reserve the address of the reserve on which the user is performing the swap
* @param _user the address of the borrower
* @param _balanceIncrease the accrued interest on the borrowed amount
* @param _currentRateMode the current rate mode of the user
**/
function updateUserStateOnSwapRateInternal(
address _reserve,
address _user,
uint256 _balanceIncrease,
CoreLibrary.InterestRateMode _currentRateMode
) internal returns (CoreLibrary.InterestRateMode) {
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
CoreLibrary.InterestRateMode newMode = CoreLibrary.InterestRateMode.NONE;
if (_currentRateMode == CoreLibrary.InterestRateMode.VARIABLE) {
//switch to stable
newMode = CoreLibrary.InterestRateMode.STABLE;
user.stableBorrowRate = reserve.currentStableBorrowRate;
user.lastVariableBorrowCumulativeIndex = 0;
} else if (_currentRateMode == CoreLibrary.InterestRateMode.STABLE) {
newMode = CoreLibrary.InterestRateMode.VARIABLE;
user.stableBorrowRate = 0;
user.lastVariableBorrowCumulativeIndex = reserve.lastVariableBorrowCumulativeIndex;
} else {
revert("Invalid interest rate mode received");
}
//compounding cumulated interest
user.principalBorrowBalance = user.principalBorrowBalance.add(_balanceIncrease);
//solium-disable-next-line
user.lastUpdateTimestamp = uint40(block.timestamp);
return newMode;
}
/**
* @dev updates the state of the principal reserve as a consequence of a liquidation action.
* @param _principalReserve the address of the principal reserve that is being repaid
* @param _user the address of the borrower
* @param _amountToLiquidate the amount being repaid by the liquidator
* @param _balanceIncrease the accrued interest on the borrowed amount
**/
function updatePrincipalReserveStateOnLiquidationInternal(
address _principalReserve,
address _user,
uint256 _amountToLiquidate,
uint256 _balanceIncrease
) internal {
CoreLibrary.ReserveData storage reserve = reserves[_principalReserve];
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_principalReserve];
//update principal reserve data
reserve.updateCumulativeIndexes();
CoreLibrary.InterestRateMode borrowRateMode = getUserCurrentBorrowRateMode(
_principalReserve,
_user
);
if (borrowRateMode == CoreLibrary.InterestRateMode.STABLE) {
//increase the total borrows by the compounded interest
reserve.increaseTotalBorrowsStableAndUpdateAverageRate(
_balanceIncrease,
user.stableBorrowRate
);
//decrease by the actual amount to liquidate
reserve.decreaseTotalBorrowsStableAndUpdateAverageRate(
_amountToLiquidate,
user.stableBorrowRate
);
} else {
//increase the total borrows by the compounded interest
reserve.increaseTotalBorrowsVariable(_balanceIncrease);
//decrease by the actual amount to liquidate
reserve.decreaseTotalBorrowsVariable(_amountToLiquidate);
}
}
/**
* @dev updates the state of the collateral reserve as a consequence of a liquidation action.
* @param _collateralReserve the address of the collateral reserve that is being liquidated
**/
function updateCollateralReserveStateOnLiquidationInternal(
address _collateralReserve
) internal {
//update collateral reserve
reserves[_collateralReserve].updateCumulativeIndexes();
}
/**
* @dev updates the state of the user being liquidated as a consequence of a liquidation action.
* @param _reserve the address of the principal reserve that is being repaid
* @param _user the address of the borrower
* @param _amountToLiquidate the amount being repaid by the liquidator
* @param _feeLiquidated the amount of origination fee being liquidated
* @param _balanceIncrease the accrued interest on the borrowed amount
**/
function updateUserStateOnLiquidationInternal(
address _reserve,
address _user,
uint256 _amountToLiquidate,
uint256 _feeLiquidated,
uint256 _balanceIncrease
) internal {
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
//first increase by the compounded interest, then decrease by the liquidated amount
user.principalBorrowBalance = user.principalBorrowBalance.add(_balanceIncrease).sub(
_amountToLiquidate
);
if (
getUserCurrentBorrowRateMode(_reserve, _user) == CoreLibrary.InterestRateMode.VARIABLE
) {
user.lastVariableBorrowCumulativeIndex = reserve.lastVariableBorrowCumulativeIndex;
}
if(_feeLiquidated > 0){
user.originationFee = user.originationFee.sub(_feeLiquidated);
}
//solium-disable-next-line
user.lastUpdateTimestamp = uint40(block.timestamp);
}
/**
* @dev updates the state of the reserve as a consequence of a stable rate rebalance
* @param _reserve the address of the principal reserve where the user borrowed
* @param _user the address of the borrower
* @param _balanceIncrease the accrued interest on the borrowed amount
**/
function updateReserveStateOnRebalanceInternal(
address _reserve,
address _user,
uint256 _balanceIncrease
) internal {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
reserve.updateCumulativeIndexes();
reserve.increaseTotalBorrowsStableAndUpdateAverageRate(
_balanceIncrease,
user.stableBorrowRate
);
}
/**
* @dev updates the state of the user as a consequence of a stable rate rebalance
* @param _reserve the address of the principal reserve where the user borrowed
* @param _user the address of the borrower
* @param _balanceIncrease the accrued interest on the borrowed amount
**/
function updateUserStateOnRebalanceInternal(
address _reserve,
address _user,
uint256 _balanceIncrease
) internal {
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
user.principalBorrowBalance = user.principalBorrowBalance.add(_balanceIncrease);
user.stableBorrowRate = reserve.currentStableBorrowRate;
//solium-disable-next-line
user.lastUpdateTimestamp = uint40(block.timestamp);
}
/**
* @dev updates the state of the user as a consequence of a stable rate rebalance
* @param _reserve the address of the principal reserve where the user borrowed
* @param _user the address of the borrower
* @param _balanceIncrease the accrued interest on the borrowed amount
* @param _amountBorrowed the accrued interest on the borrowed amount
**/
function updateReserveTotalBorrowsByRateModeInternal(
address _reserve,
address _user,
uint256 _principalBalance,
uint256 _balanceIncrease,
uint256 _amountBorrowed,
CoreLibrary.InterestRateMode _newBorrowRateMode
) internal {
CoreLibrary.InterestRateMode previousRateMode = getUserCurrentBorrowRateMode(
_reserve,
_user
);
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
if (previousRateMode == CoreLibrary.InterestRateMode.STABLE) {
CoreLibrary.UserReserveData storage user = usersReserveData[_user][_reserve];
reserve.decreaseTotalBorrowsStableAndUpdateAverageRate(
_principalBalance,
user.stableBorrowRate
);
} else if (previousRateMode == CoreLibrary.InterestRateMode.VARIABLE) {
reserve.decreaseTotalBorrowsVariable(_principalBalance);
}
uint256 newPrincipalAmount = _principalBalance.add(_balanceIncrease).add(_amountBorrowed);
if (_newBorrowRateMode == CoreLibrary.InterestRateMode.STABLE) {
reserve.increaseTotalBorrowsStableAndUpdateAverageRate(
newPrincipalAmount,
reserve.currentStableBorrowRate
);
} else if (_newBorrowRateMode == CoreLibrary.InterestRateMode.VARIABLE) {
reserve.increaseTotalBorrowsVariable(newPrincipalAmount);
} else {
revert("Invalid new borrow rate mode");
}
}
/**
* @dev Updates the reserve current stable borrow rate Rf, the current variable borrow rate Rv and the current liquidity rate Rl.
* Also updates the lastUpdateTimestamp value. Please refer to the whitepaper for further information.
* @param _reserve the address of the reserve to be updated
* @param _liquidityAdded the amount of liquidity added to the protocol (deposit or repay) in the previous action
* @param _liquidityTaken the amount of liquidity taken from the protocol (redeem or borrow)
**/
function updateReserveInterestRatesAndTimestampInternal(
address _reserve,
uint256 _liquidityAdded,
uint256 _liquidityTaken
) internal {
CoreLibrary.ReserveData storage reserve = reserves[_reserve];
(uint256 newLiquidityRate, uint256 newStableRate, uint256 newVariableRate) = IReserveInterestRateStrategy(
reserve
.interestRateStrategyAddress
)
.calculateInterestRates(
_reserve,
getReserveAvailableLiquidity(_reserve).add(_liquidityAdded).sub(_liquidityTaken),
reserve.totalBorrowsStable,
reserve.totalBorrowsVariable,
reserve.currentAverageStableBorrowRate
);
reserve.currentLiquidityRate = newLiquidityRate;
reserve.currentStableBorrowRate = newStableRate;
reserve.currentVariableBorrowRate = newVariableRate;
//solium-disable-next-line
reserve.lastUpdateTimestamp = uint40(block.timestamp);
emit ReserveUpdated(
_reserve,
newLiquidityRate,
newStableRate,
newVariableRate,
reserve.lastLiquidityCumulativeIndex,
reserve.lastVariableBorrowCumulativeIndex
);
}
/**
* @dev transfers to the protocol fees of a flashloan to the fees collection address
* @param _token the address of the token being transferred
* @param _amount the amount being transferred
**/
function transferFlashLoanProtocolFeeInternal(address _token, uint256 _amount) internal {
address payable receiver = address(uint160(addressesProvider.getTokenDistributor()));
if (_token != EthAddressLib.ethAddress()) {
ERC20(_token).safeTransfer(receiver, _amount);
} else {
receiver.transfer(_amount);
}
}
/**
* @dev updates the internal configuration of the core
**/
function refreshConfigInternal() internal {
lendingPoolAddress = addressesProvider.getLendingPool();
}
/**
* @dev adds a reserve to the array of the reserves address
**/
function addReserveToListInternal(address _reserve) internal {
bool reserveAlreadyAdded = false;
for (uint256 i = 0; i < reservesList.length; i++)
if (reservesList[i] == _reserve) {
reserveAlreadyAdded = true;
}
if (!reserveAlreadyAdded) reservesList.push(_reserve);
}
}
/**
* @title LendingPool contract
* @notice Implements the actions of the LendingPool, and exposes accessory methods to fetch the users and reserve data
* @author Aave
**/
contract LendingPool is ReentrancyGuard, VersionedInitializable {
using SafeMath for uint256;
using WadRayMath for uint256;
using Address for address;
LendingPoolAddressesProvider public addressesProvider;
LendingPoolCore public core;
LendingPoolDataProvider public dataProvider;
LendingPoolParametersProvider public parametersProvider;
IFeeProvider feeProvider;
/**
* @dev emitted on deposit
* @param _reserve the address of the reserve
* @param _user the address of the user
* @param _amount the amount to be deposited
* @param _referral the referral number of the action
* @param _timestamp the timestamp of the action
**/
event Deposit(
address indexed _reserve,
address indexed _user,
uint256 _amount,
uint16 indexed _referral,
uint256 _timestamp
);
/**
* @dev emitted during a redeem action.
* @param _reserve the address of the reserve
* @param _user the address of the user
* @param _amount the amount to be deposited
* @param _timestamp the timestamp of the action
**/
event RedeemUnderlying(
address indexed _reserve,
address indexed _user,
uint256 _amount,
uint256 _timestamp
);
/**
* @dev emitted on borrow
* @param _reserve the address of the reserve
* @param _user the address of the user
* @param _amount the amount to be deposited
* @param _borrowRateMode the rate mode, can be either 1-stable or 2-variable
* @param _borrowRate the rate at which the user has borrowed
* @param _originationFee the origination fee to be paid by the user
* @param _borrowBalanceIncrease the balance increase since the last borrow, 0 if it's the first time borrowing
* @param _referral the referral number of the action
* @param _timestamp the timestamp of the action
**/
event Borrow(
address indexed _reserve,
address indexed _user,
uint256 _amount,
uint256 _borrowRateMode,
uint256 _borrowRate,
uint256 _originationFee,
uint256 _borrowBalanceIncrease,
uint16 indexed _referral,
uint256 _timestamp
);
/**
* @dev emitted on repay
* @param _reserve the address of the reserve
* @param _user the address of the user for which the repay has been executed
* @param _repayer the address of the user that has performed the repay action
* @param _amountMinusFees the amount repaid minus fees
* @param _fees the fees repaid
* @param _borrowBalanceIncrease the balance increase since the last action
* @param _timestamp the timestamp of the action
**/
event Repay(
address indexed _reserve,
address indexed _user,
address indexed _repayer,
uint256 _amountMinusFees,
uint256 _fees,
uint256 _borrowBalanceIncrease,
uint256 _timestamp
);
/**
* @dev emitted when a user performs a rate swap
* @param _reserve the address of the reserve
* @param _user the address of the user executing the swap
* @param _newRateMode the new interest rate mode
* @param _newRate the new borrow rate
* @param _borrowBalanceIncrease the balance increase since the last action
* @param _timestamp the timestamp of the action
**/
event Swap(
address indexed _reserve,
address indexed _user,
uint256 _newRateMode,
uint256 _newRate,
uint256 _borrowBalanceIncrease,
uint256 _timestamp
);
/**
* @dev emitted when a user enables a reserve as collateral
* @param _reserve the address of the reserve
* @param _user the address of the user
**/
event ReserveUsedAsCollateralEnabled(address indexed _reserve, address indexed _user);
/**
* @dev emitted when a user disables a reserve as collateral
* @param _reserve the address of the reserve
* @param _user the address of the user
**/
event ReserveUsedAsCollateralDisabled(address indexed _reserve, address indexed _user);
/**
* @dev emitted when the stable rate of a user gets rebalanced
* @param _reserve the address of the reserve
* @param _user the address of the user for which the rebalance has been executed
* @param _newStableRate the new stable borrow rate after the rebalance
* @param _borrowBalanceIncrease the balance increase since the last action
* @param _timestamp the timestamp of the action
**/
event RebalanceStableBorrowRate(
address indexed _reserve,
address indexed _user,
uint256 _newStableRate,
uint256 _borrowBalanceIncrease,
uint256 _timestamp
);
/**
* @dev emitted when a flashloan is executed
* @param _target the address of the flashLoanReceiver
* @param _reserve the address of the reserve
* @param _amount the amount requested
* @param _totalFee the total fee on the amount
* @param _protocolFee the part of the fee for the protocol
* @param _timestamp the timestamp of the action
**/
event FlashLoan(
address indexed _target,
address indexed _reserve,
uint256 _amount,
uint256 _totalFee,
uint256 _protocolFee,
uint256 _timestamp
);
/**
* @dev these events are not emitted directly by the LendingPool
* but they are declared here as the LendingPoolLiquidationManager
* is executed using a delegateCall().
* This allows to have the events in the generated ABI for LendingPool.
**/
/**
* @dev emitted when a borrow fee is liquidated
* @param _collateral the address of the collateral being liquidated
* @param _reserve the address of the reserve
* @param _user the address of the user being liquidated
* @param _feeLiquidated the total fee liquidated
* @param _liquidatedCollateralForFee the amount of collateral received by the protocol in exchange for the fee
* @param _timestamp the timestamp of the action
**/
event OriginationFeeLiquidated(
address indexed _collateral,
address indexed _reserve,
address indexed _user,
uint256 _feeLiquidated,
uint256 _liquidatedCollateralForFee,
uint256 _timestamp
);
/**
* @dev emitted when a borrower is liquidated
* @param _collateral the address of the collateral being liquidated
* @param _reserve the address of the reserve
* @param _user the address of the user being liquidated
* @param _purchaseAmount the total amount liquidated
* @param _liquidatedCollateralAmount the amount of collateral being liquidated
* @param _accruedBorrowInterest the amount of interest accrued by the borrower since the last action
* @param _liquidator the address of the liquidator
* @param _receiveAToken true if the liquidator wants to receive aTokens, false otherwise
* @param _timestamp the timestamp of the action
**/
event LiquidationCall(
address indexed _collateral,
address indexed _reserve,
address indexed _user,
uint256 _purchaseAmount,
uint256 _liquidatedCollateralAmount,
uint256 _accruedBorrowInterest,
address _liquidator,
bool _receiveAToken,
uint256 _timestamp
);
/**
* @dev functions affected by this modifier can only be invoked by the
* aToken.sol contract
* @param _reserve the address of the reserve
**/
modifier onlyOverlyingAToken(address _reserve) {
require(
msg.sender == core.getReserveATokenAddress(_reserve),
"The caller of this function can only be the aToken contract of this reserve"
);
_;
}
/**
* @dev functions affected by this modifier can only be invoked if the reserve is active
* @param _reserve the address of the reserve
**/
modifier onlyActiveReserve(address _reserve) {
requireReserveActiveInternal(_reserve);
_;
}
/**
* @dev functions affected by this modifier can only be invoked if the reserve is not freezed.
* A freezed reserve only allows redeems, repays, rebalances and liquidations.
* @param _reserve the address of the reserve
**/
modifier onlyUnfreezedReserve(address _reserve) {
requireReserveNotFreezedInternal(_reserve);
_;
}
/**
* @dev functions affected by this modifier can only be invoked if the provided _amount input parameter
* is not zero.
* @param _amount the amount provided
**/
modifier onlyAmountGreaterThanZero(uint256 _amount) {
requireAmountGreaterThanZeroInternal(_amount);
_;
}
uint256 public constant UINT_MAX_VALUE = uint256(-1);
uint256 public constant LENDINGPOOL_REVISION = 0x2;
function getRevision() internal pure returns (uint256) {
return LENDINGPOOL_REVISION;
}
/**
* @dev this function is invoked by the proxy contract when the LendingPool contract is added to the
* AddressesProvider.
* @param _addressesProvider the address of the LendingPoolAddressesProvider registry
**/
function initialize(LendingPoolAddressesProvider _addressesProvider) public initializer {
addressesProvider = _addressesProvider;
core = LendingPoolCore(addressesProvider.getLendingPoolCore());
dataProvider = LendingPoolDataProvider(addressesProvider.getLendingPoolDataProvider());
parametersProvider = LendingPoolParametersProvider(
addressesProvider.getLendingPoolParametersProvider()
);
feeProvider = IFeeProvider(addressesProvider.getFeeProvider());
}
/**
* @dev deposits The underlying asset into the reserve. A corresponding amount of the overlying asset (aTokens)
* is minted.
* @param _reserve the address of the reserve
* @param _amount the amount to be deposited
* @param _referralCode integrators are assigned a referral code and can potentially receive rewards.
**/
function deposit(address _reserve, uint256 _amount, uint16 _referralCode)
external
payable
nonReentrant
onlyActiveReserve(_reserve)
onlyUnfreezedReserve(_reserve)
onlyAmountGreaterThanZero(_amount)
{
AToken aToken = AToken(core.getReserveATokenAddress(_reserve));
bool isFirstDeposit = aToken.balanceOf(msg.sender) == 0;
core.updateStateOnDeposit(_reserve, msg.sender, _amount, isFirstDeposit);
//minting AToken to user 1:1 with the specific exchange rate
aToken.mintOnDeposit(msg.sender, _amount);
//transfer to the core contract
core.transferToReserve.value(msg.value)(_reserve, msg.sender, _amount);
//solium-disable-next-line
emit Deposit(_reserve, msg.sender, _amount, _referralCode, block.timestamp);
}
/**
* @dev Redeems the underlying amount of assets requested by _user.
* This function is executed by the overlying aToken contract in response to a redeem action.
* @param _reserve the address of the reserve
* @param _user the address of the user performing the action
* @param _amount the underlying amount to be redeemed
**/
function redeemUnderlying(
address _reserve,
address payable _user,
uint256 _amount,
uint256 _aTokenBalanceAfterRedeem
)
external
nonReentrant
onlyOverlyingAToken(_reserve)
onlyActiveReserve(_reserve)
onlyAmountGreaterThanZero(_amount)
{
uint256 currentAvailableLiquidity = core.getReserveAvailableLiquidity(_reserve);
require(
currentAvailableLiquidity >= _amount,
"There is not enough liquidity available to redeem"
);
core.updateStateOnRedeem(_reserve, _user, _amount, _aTokenBalanceAfterRedeem == 0);
core.transferToUser(_reserve, _user, _amount);
//solium-disable-next-line
emit RedeemUnderlying(_reserve, _user, _amount, block.timestamp);
}
/**
* @dev data structures for local computations in the borrow() method.
*/
struct BorrowLocalVars {
uint256 principalBorrowBalance;
uint256 currentLtv;
uint256 currentLiquidationThreshold;
uint256 borrowFee;
uint256 requestedBorrowAmountETH;
uint256 amountOfCollateralNeededETH;
uint256 userCollateralBalanceETH;
uint256 userBorrowBalanceETH;
uint256 userTotalFeesETH;
uint256 borrowBalanceIncrease;
uint256 currentReserveStableRate;
uint256 availableLiquidity;
uint256 reserveDecimals;
uint256 finalUserBorrowRate;
CoreLibrary.InterestRateMode rateMode;
bool healthFactorBelowThreshold;
}
/**
* @dev Allows users to borrow a specific amount of the reserve currency, provided that the borrower
* already deposited enough collateral.
* @param _reserve the address of the reserve
* @param _amount the amount to be borrowed
* @param _interestRateMode the interest rate mode at which the user wants to borrow. Can be 0 (STABLE) or 1 (VARIABLE)
**/
function borrow(
address _reserve,
uint256 _amount,
uint256 _interestRateMode,
uint16 _referralCode
)
external
nonReentrant
onlyActiveReserve(_reserve)
onlyUnfreezedReserve(_reserve)
onlyAmountGreaterThanZero(_amount)
{
// Usage of a memory struct of vars to avoid "Stack too deep" errors due to local variables
BorrowLocalVars memory vars;
//check that the reserve is enabled for borrowing
require(core.isReserveBorrowingEnabled(_reserve), "Reserve is not enabled for borrowing");
//validate interest rate mode
require(
uint256(CoreLibrary.InterestRateMode.VARIABLE) == _interestRateMode ||
uint256(CoreLibrary.InterestRateMode.STABLE) == _interestRateMode,
"Invalid interest rate mode selected"
);
//cast the rateMode to coreLibrary.interestRateMode
vars.rateMode = CoreLibrary.InterestRateMode(_interestRateMode);
//check that the amount is available in the reserve
vars.availableLiquidity = core.getReserveAvailableLiquidity(_reserve);
require(
vars.availableLiquidity >= _amount,
"There is not enough liquidity available in the reserve"
);
(
,
vars.userCollateralBalanceETH,
vars.userBorrowBalanceETH,
vars.userTotalFeesETH,
vars.currentLtv,
vars.currentLiquidationThreshold,
,
vars.healthFactorBelowThreshold
) = dataProvider.calculateUserGlobalData(msg.sender);
require(vars.userCollateralBalanceETH > 0, "The collateral balance is 0");
require(
!vars.healthFactorBelowThreshold,
"The borrower can already be liquidated so he cannot borrow more"
);
//calculating fees
vars.borrowFee = feeProvider.calculateLoanOriginationFee(msg.sender, _amount);
require(vars.borrowFee > 0, "The amount to borrow is too small");
vars.amountOfCollateralNeededETH = dataProvider.calculateCollateralNeededInETH(
_reserve,
_amount,
vars.borrowFee,
vars.userBorrowBalanceETH,
vars.userTotalFeesETH,
vars.currentLtv
);
require(
vars.amountOfCollateralNeededETH <= vars.userCollateralBalanceETH,
"There is not enough collateral to cover a new borrow"
);
/**
* Following conditions need to be met if the user is borrowing at a stable rate:
* 1. Reserve must be enabled for stable rate borrowing
* 2. Users cannot borrow from the reserve if their collateral is (mostly) the same currency
* they are borrowing, to prevent abuses.
* 3. Users will be able to borrow only a relatively small, configurable amount of the total
* liquidity
**/
if (vars.rateMode == CoreLibrary.InterestRateMode.STABLE) {
//check if the borrow mode is stable and if stable rate borrowing is enabled on this reserve
require(
core.isUserAllowedToBorrowAtStable(_reserve, msg.sender, _amount),
"User cannot borrow the selected amount with a stable rate"
);
//calculate the max available loan size in stable rate mode as a percentage of the
//available liquidity
uint256 maxLoanPercent = parametersProvider.getMaxStableRateBorrowSizePercent();
uint256 maxLoanSizeStable = vars.availableLiquidity.mul(maxLoanPercent).div(100);
require(
_amount <= maxLoanSizeStable,
"User is trying to borrow too much liquidity at a stable rate"
);
}
//all conditions passed - borrow is accepted
(vars.finalUserBorrowRate, vars.borrowBalanceIncrease) = core.updateStateOnBorrow(
_reserve,
msg.sender,
_amount,
vars.borrowFee,
vars.rateMode
);
//if we reached this point, we can transfer
core.transferToUser(_reserve, msg.sender, _amount);
emit Borrow(
_reserve,
msg.sender,
_amount,
_interestRateMode,
vars.finalUserBorrowRate,
vars.borrowFee,
vars.borrowBalanceIncrease,
_referralCode,
//solium-disable-next-line
block.timestamp
);
}
/**
* @notice repays a borrow on the specific reserve, for the specified amount (or for the whole amount, if uint256(-1) is specified).
* @dev the target user is defined by _onBehalfOf. If there is no repayment on behalf of another account,
* _onBehalfOf must be equal to msg.sender.
* @param _reserve the address of the reserve on which the user borrowed
* @param _amount the amount to repay, or uint256(-1) if the user wants to repay everything
* @param _onBehalfOf the address for which msg.sender is repaying.
**/
struct RepayLocalVars {
uint256 principalBorrowBalance;
uint256 compoundedBorrowBalance;
uint256 borrowBalanceIncrease;
bool isETH;
uint256 paybackAmount;
uint256 paybackAmountMinusFees;
uint256 currentStableRate;
uint256 originationFee;
}
function repay(address _reserve, uint256 _amount, address payable _onBehalfOf)
external
payable
nonReentrant
onlyActiveReserve(_reserve)
onlyAmountGreaterThanZero(_amount)
{
// Usage of a memory struct of vars to avoid "Stack too deep" errors due to local variables
RepayLocalVars memory vars;
(
vars.principalBorrowBalance,
vars.compoundedBorrowBalance,
vars.borrowBalanceIncrease
) = core.getUserBorrowBalances(_reserve, _onBehalfOf);
vars.originationFee = core.getUserOriginationFee(_reserve, _onBehalfOf);
vars.isETH = EthAddressLib.ethAddress() == _reserve;
require(vars.compoundedBorrowBalance > 0, "The user does not have any borrow pending");
require(
_amount != UINT_MAX_VALUE || msg.sender == _onBehalfOf,
"To repay on behalf of an user an explicit amount to repay is needed."
);
//default to max amount
vars.paybackAmount = vars.compoundedBorrowBalance.add(vars.originationFee);
if (_amount != UINT_MAX_VALUE && _amount < vars.paybackAmount) {
vars.paybackAmount = _amount;
}
require(
!vars.isETH || msg.value >= vars.paybackAmount,
"Invalid msg.value sent for the repayment"
);
//if the amount is smaller than the origination fee, just transfer the amount to the fee destination address
if (vars.paybackAmount <= vars.originationFee) {
core.updateStateOnRepay(
_reserve,
_onBehalfOf,
0,
vars.paybackAmount,
vars.borrowBalanceIncrease,
false
);
core.transferToFeeCollectionAddress.value(vars.isETH ? vars.paybackAmount : 0)(
_reserve,
_onBehalfOf,
vars.paybackAmount,
addressesProvider.getTokenDistributor()
);
emit Repay(
_reserve,
_onBehalfOf,
msg.sender,
0,
vars.paybackAmount,
vars.borrowBalanceIncrease,
//solium-disable-next-line
block.timestamp
);
return;
}
vars.paybackAmountMinusFees = vars.paybackAmount.sub(vars.originationFee);
core.updateStateOnRepay(
_reserve,
_onBehalfOf,
vars.paybackAmountMinusFees,
vars.originationFee,
vars.borrowBalanceIncrease,
vars.compoundedBorrowBalance == vars.paybackAmountMinusFees
);
//if the user didn't repay the origination fee, transfer the fee to the fee collection address
if(vars.originationFee > 0) {
core.transferToFeeCollectionAddress.value(vars.isETH ? vars.originationFee : 0)(
_reserve,
_onBehalfOf,
vars.originationFee,
addressesProvider.getTokenDistributor()
);
}
//sending the total msg.value if the transfer is ETH.
//the transferToReserve() function will take care of sending the
//excess ETH back to the caller
core.transferToReserve.value(vars.isETH ? msg.value.sub(vars.originationFee) : 0)(
_reserve,
msg.sender,
vars.paybackAmountMinusFees
);
emit Repay(
_reserve,
_onBehalfOf,
msg.sender,
vars.paybackAmountMinusFees,
vars.originationFee,
vars.borrowBalanceIncrease,
//solium-disable-next-line
block.timestamp
);
}
/**
* @dev borrowers can user this function to swap between stable and variable borrow rate modes.
* @param _reserve the address of the reserve on which the user borrowed
**/
function swapBorrowRateMode(address _reserve)
external
nonReentrant
onlyActiveReserve(_reserve)
onlyUnfreezedReserve(_reserve)
{
(uint256 principalBorrowBalance, uint256 compoundedBorrowBalance, uint256 borrowBalanceIncrease) = core
.getUserBorrowBalances(_reserve, msg.sender);
require(
compoundedBorrowBalance > 0,
"User does not have a borrow in progress on this reserve"
);
CoreLibrary.InterestRateMode currentRateMode = core.getUserCurrentBorrowRateMode(
_reserve,
msg.sender
);
if (currentRateMode == CoreLibrary.InterestRateMode.VARIABLE) {
/**
* user wants to swap to stable, before swapping we need to ensure that
* 1. stable borrow rate is enabled on the reserve
* 2. user is not trying to abuse the reserve by depositing
* more collateral than he is borrowing, artificially lowering
* the interest rate, borrowing at variable, and switching to stable
**/
require(
core.isUserAllowedToBorrowAtStable(_reserve, msg.sender, compoundedBorrowBalance),
"User cannot borrow the selected amount at stable"
);
}
(CoreLibrary.InterestRateMode newRateMode, uint256 newBorrowRate) = core
.updateStateOnSwapRate(
_reserve,
msg.sender,
principalBorrowBalance,
compoundedBorrowBalance,
borrowBalanceIncrease,
currentRateMode
);
emit Swap(
_reserve,
msg.sender,
uint256(newRateMode),
newBorrowRate,
borrowBalanceIncrease,
//solium-disable-next-line
block.timestamp
);
}
/**
* @dev rebalances the stable interest rate of a user if current liquidity rate > user stable rate.
* this is regulated by Aave to ensure that the protocol is not abused, and the user is paying a fair
* rate. Anyone can call this function though.
* @param _reserve the address of the reserve
* @param _user the address of the user to be rebalanced
**/
function rebalanceStableBorrowRate(address _reserve, address _user)
external
nonReentrant
onlyActiveReserve(_reserve)
{
(, uint256 compoundedBalance, uint256 borrowBalanceIncrease) = core.getUserBorrowBalances(
_reserve,
_user
);
//step 1: user must be borrowing on _reserve at a stable rate
require(compoundedBalance > 0, "User does not have any borrow for this reserve");
require(
core.getUserCurrentBorrowRateMode(_reserve, _user) ==
CoreLibrary.InterestRateMode.STABLE,
"The user borrow is variable and cannot be rebalanced"
);
uint256 userCurrentStableRate = core.getUserCurrentStableBorrowRate(_reserve, _user);
uint256 liquidityRate = core.getReserveCurrentLiquidityRate(_reserve);
uint256 reserveCurrentStableRate = core.getReserveCurrentStableBorrowRate(_reserve);
uint256 rebalanceDownRateThreshold = reserveCurrentStableRate.rayMul(
WadRayMath.ray().add(parametersProvider.getRebalanceDownRateDelta())
);
//step 2: we have two possible situations to rebalance:
//1. user stable borrow rate is below the current liquidity rate. The loan needs to be rebalanced,
//as this situation can be abused (user putting back the borrowed liquidity in the same reserve to earn on it)
//2. user stable rate is above the market avg borrow rate of a certain delta, and utilization rate is low.
//In this case, the user is paying an interest that is too high, and needs to be rescaled down.
if (
userCurrentStableRate < liquidityRate ||
userCurrentStableRate > rebalanceDownRateThreshold
) {
uint256 newStableRate = core.updateStateOnRebalance(
_reserve,
_user,
borrowBalanceIncrease
);
emit RebalanceStableBorrowRate(
_reserve,
_user,
newStableRate,
borrowBalanceIncrease,
//solium-disable-next-line
block.timestamp
);
return;
}
revert("Interest rate rebalance conditions were not met");
}
/**
* @dev allows depositors to enable or disable a specific deposit as collateral.
* @param _reserve the address of the reserve
* @param _useAsCollateral true if the user wants to user the deposit as collateral, false otherwise.
**/
function setUserUseReserveAsCollateral(address _reserve, bool _useAsCollateral)
external
nonReentrant
onlyActiveReserve(_reserve)
onlyUnfreezedReserve(_reserve)
{
uint256 underlyingBalance = core.getUserUnderlyingAssetBalance(_reserve, msg.sender);
require(underlyingBalance > 0, "User does not have any liquidity deposited");
require(
dataProvider.balanceDecreaseAllowed(_reserve, msg.sender, underlyingBalance),
"User deposit is already being used as collateral"
);
core.setUserUseReserveAsCollateral(_reserve, msg.sender, _useAsCollateral);
if (_useAsCollateral) {
emit ReserveUsedAsCollateralEnabled(_reserve, msg.sender);
} else {
emit ReserveUsedAsCollateralDisabled(_reserve, msg.sender);
}
}
/**
* @dev users can invoke this function to liquidate an undercollateralized position.
* @param _reserve the address of the collateral to liquidated
* @param _reserve the address of the principal reserve
* @param _user the address of the borrower
* @param _purchaseAmount the amount of principal that the liquidator wants to repay
* @param _receiveAToken true if the liquidators wants to receive the aTokens, false if
* he wants to receive the underlying asset directly
**/
function liquidationCall(
address _collateral,
address _reserve,
address _user,
uint256 _purchaseAmount,
bool _receiveAToken
) external payable nonReentrant onlyActiveReserve(_reserve) onlyActiveReserve(_collateral) {
address liquidationManager = addressesProvider.getLendingPoolLiquidationManager();
//solium-disable-next-line
(bool success, bytes memory result) = liquidationManager.delegatecall(
abi.encodeWithSignature(
"liquidationCall(address,address,address,uint256,bool)",
_collateral,
_reserve,
_user,
_purchaseAmount,
_receiveAToken
)
);
require(success, "Liquidation call failed");
(uint256 returnCode, string memory returnMessage) = abi.decode(result, (uint256, string));
if (returnCode != 0) {
//error found
revert(string(abi.encodePacked("Liquidation failed: ", returnMessage)));
}
}
/**
* @dev allows smartcontracts to access the liquidity of the pool within one transaction,
* as long as the amount taken plus a fee is returned. NOTE There are security concerns for developers of flashloan receiver contracts
* that must be kept into consideration. For further details please visit https://developers.aave.com
* @param _receiver The address of the contract receiving the funds. The receiver should implement the IFlashLoanReceiver interface.
* @param _reserve the address of the principal reserve
* @param _amount the amount requested for this flashloan
**/
function flashLoan(address _receiver, address _reserve, uint256 _amount, bytes memory _params)
public
nonReentrant
onlyActiveReserve(_reserve)
onlyAmountGreaterThanZero(_amount)
{
//check that the reserve has enough available liquidity
//we avoid using the getAvailableLiquidity() function in LendingPoolCore to save gas
uint256 availableLiquidityBefore = _reserve == EthAddressLib.ethAddress()
? address(core).balance
: IERC20(_reserve).balanceOf(address(core));
require(
availableLiquidityBefore >= _amount,
"There is not enough liquidity available to borrow"
);
(uint256 totalFeeBips, uint256 protocolFeeBips) = parametersProvider
.getFlashLoanFeesInBips();
//calculate amount fee
uint256 amountFee = _amount.mul(totalFeeBips).div(10000);
//protocol fee is the part of the amountFee reserved for the protocol - the rest goes to depositors
uint256 protocolFee = amountFee.mul(protocolFeeBips).div(10000);
require(
amountFee > 0 && protocolFee > 0,
"The requested amount is too small for a flashLoan."
);
//get the FlashLoanReceiver instance
IFlashLoanReceiver receiver = IFlashLoanReceiver(_receiver);
address payable userPayable = address(uint160(_receiver));
//transfer funds to the receiver
core.transferToUser(_reserve, userPayable, _amount);
//execute action of the receiver
receiver.executeOperation(_reserve, _amount, amountFee, _params);
//check that the actual balance of the core contract includes the returned amount
uint256 availableLiquidityAfter = _reserve == EthAddressLib.ethAddress()
? address(core).balance
: IERC20(_reserve).balanceOf(address(core));
require(
availableLiquidityAfter == availableLiquidityBefore.add(amountFee),
"The actual balance of the protocol is inconsistent"
);
core.updateStateOnFlashLoan(
_reserve,
availableLiquidityBefore,
amountFee.sub(protocolFee),
protocolFee
);
//solium-disable-next-line
emit FlashLoan(_receiver, _reserve, _amount, amountFee, protocolFee, block.timestamp);
}
/**
* @dev accessory functions to fetch data from the core contract
**/
function getReserveConfigurationData(address _reserve)
external
view
returns (
uint256 ltv,
uint256 liquidationThreshold,
uint256 liquidationBonus,
address interestRateStrategyAddress,
bool usageAsCollateralEnabled,
bool borrowingEnabled,
bool stableBorrowRateEnabled,
bool isActive
)
{
return dataProvider.getReserveConfigurationData(_reserve);
}
function getReserveData(address _reserve)
external
view
returns (
uint256 totalLiquidity,
uint256 availableLiquidity,
uint256 totalBorrowsStable,
uint256 totalBorrowsVariable,
uint256 liquidityRate,
uint256 variableBorrowRate,
uint256 stableBorrowRate,
uint256 averageStableBorrowRate,
uint256 utilizationRate,
uint256 liquidityIndex,
uint256 variableBorrowIndex,
address aTokenAddress,
uint40 lastUpdateTimestamp
)
{
return dataProvider.getReserveData(_reserve);
}
function getUserAccountData(address _user)
external
view
returns (
uint256 totalLiquidityETH,
uint256 totalCollateralETH,
uint256 totalBorrowsETH,
uint256 totalFeesETH,
uint256 availableBorrowsETH,
uint256 currentLiquidationThreshold,
uint256 ltv,
uint256 healthFactor
)
{
return dataProvider.getUserAccountData(_user);
}
function getUserReserveData(address _reserve, address _user)
external
view
returns (
uint256 currentATokenBalance,
uint256 currentBorrowBalance,
uint256 principalBorrowBalance,
uint256 borrowRateMode,
uint256 borrowRate,
uint256 liquidityRate,
uint256 originationFee,
uint256 variableBorrowIndex,
uint256 lastUpdateTimestamp,
bool usageAsCollateralEnabled
)
{
return dataProvider.getUserReserveData(_reserve, _user);
}
function getReserves() external view returns (address[] memory) {
return core.getReserves();
}
/**
* @dev internal function to save on code size for the onlyActiveReserve modifier
**/
function requireReserveActiveInternal(address _reserve) internal view {
require(core.getReserveIsActive(_reserve), "Action requires an active reserve");
}
/**
* @notice internal function to save on code size for the onlyUnfreezedReserve modifier
**/
function requireReserveNotFreezedInternal(address _reserve) internal view {
require(!core.getReserveIsFreezed(_reserve), "Action requires an unfreezed reserve");
}
/**
* @notice internal function to save on code size for the onlyAmountGreaterThanZero modifier
**/
function requireAmountGreaterThanZeroInternal(uint256 _amount) internal pure {
require(_amount > 0, "Amount must be greater than 0");
}
}
/**
* @title LendingPoolLiquidationManager contract
* @author Aave
* @notice Implements the liquidation function.
**/
contract LendingPoolLiquidationManager is ReentrancyGuard, VersionedInitializable {
using SafeMath for uint256;
using WadRayMath for uint256;
using Address for address;
LendingPoolAddressesProvider public addressesProvider;
LendingPoolCore core;
LendingPoolDataProvider dataProvider;
LendingPoolParametersProvider parametersProvider;
IFeeProvider feeProvider;
address ethereumAddress;
uint256 constant LIQUIDATION_CLOSE_FACTOR_PERCENT = 50;
/**
* @dev emitted when a borrow fee is liquidated
* @param _collateral the address of the collateral being liquidated
* @param _reserve the address of the reserve
* @param _user the address of the user being liquidated
* @param _feeLiquidated the total fee liquidated
* @param _liquidatedCollateralForFee the amount of collateral received by the protocol in exchange for the fee
* @param _timestamp the timestamp of the action
**/
event OriginationFeeLiquidated(
address indexed _collateral,
address indexed _reserve,
address indexed _user,
uint256 _feeLiquidated,
uint256 _liquidatedCollateralForFee,
uint256 _timestamp
);
/**
* @dev emitted when a borrower is liquidated
* @param _collateral the address of the collateral being liquidated
* @param _reserve the address of the reserve
* @param _user the address of the user being liquidated
* @param _purchaseAmount the total amount liquidated
* @param _liquidatedCollateralAmount the amount of collateral being liquidated
* @param _accruedBorrowInterest the amount of interest accrued by the borrower since the last action
* @param _liquidator the address of the liquidator
* @param _receiveAToken true if the liquidator wants to receive aTokens, false otherwise
* @param _timestamp the timestamp of the action
**/
event LiquidationCall(
address indexed _collateral,
address indexed _reserve,
address indexed _user,
uint256 _purchaseAmount,
uint256 _liquidatedCollateralAmount,
uint256 _accruedBorrowInterest,
address _liquidator,
bool _receiveAToken,
uint256 _timestamp
);
enum LiquidationErrors {
NO_ERROR,
NO_COLLATERAL_AVAILABLE,
COLLATERAL_CANNOT_BE_LIQUIDATED,
CURRRENCY_NOT_BORROWED,
HEALTH_FACTOR_ABOVE_THRESHOLD,
NOT_ENOUGH_LIQUIDITY
}
struct LiquidationCallLocalVars {
uint256 userCollateralBalance;
uint256 userCompoundedBorrowBalance;
uint256 borrowBalanceIncrease;
uint256 maxPrincipalAmountToLiquidate;
uint256 actualAmountToLiquidate;
uint256 liquidationRatio;
uint256 collateralPrice;
uint256 principalCurrencyPrice;
uint256 maxAmountCollateralToLiquidate;
uint256 originationFee;
uint256 feeLiquidated;
uint256 liquidatedCollateralForFee;
CoreLibrary.InterestRateMode borrowRateMode;
uint256 userStableRate;
bool isCollateralEnabled;
bool healthFactorBelowThreshold;
}
/**
* @dev as the contract extends the VersionedInitializable contract to match the state
* of the LendingPool contract, the getRevision() function is needed.
*/
function getRevision() internal pure returns (uint256) {
return 0;
}
/**
* @dev users can invoke this function to liquidate an undercollateralized position.
* @param _reserve the address of the collateral to liquidated
* @param _reserve the address of the principal reserve
* @param _user the address of the borrower
* @param _purchaseAmount the amount of principal that the liquidator wants to repay
* @param _receiveAToken true if the liquidators wants to receive the aTokens, false if
* he wants to receive the underlying asset directly
**/
function liquidationCall(
address _collateral,
address _reserve,
address _user,
uint256 _purchaseAmount,
bool _receiveAToken
) external payable returns (uint256, string memory) {
// Usage of a memory struct of vars to avoid "Stack too deep" errors due to local variables
LiquidationCallLocalVars memory vars;
(, , , , , , , vars.healthFactorBelowThreshold) = dataProvider.calculateUserGlobalData(
_user
);
if (!vars.healthFactorBelowThreshold) {
return (
uint256(LiquidationErrors.HEALTH_FACTOR_ABOVE_THRESHOLD),
"Health factor is not below the threshold"
);
}
vars.userCollateralBalance = core.getUserUnderlyingAssetBalance(_collateral, _user);
//if _user hasn't deposited this specific collateral, nothing can be liquidated
if (vars.userCollateralBalance == 0) {
return (
uint256(LiquidationErrors.NO_COLLATERAL_AVAILABLE),
"Invalid collateral to liquidate"
);
}
vars.isCollateralEnabled =
core.isReserveUsageAsCollateralEnabled(_collateral) &&
core.isUserUseReserveAsCollateralEnabled(_collateral, _user);
//if _collateral isn't enabled as collateral by _user, it cannot be liquidated
if (!vars.isCollateralEnabled) {
return (
uint256(LiquidationErrors.COLLATERAL_CANNOT_BE_LIQUIDATED),
"The collateral chosen cannot be liquidated"
);
}
//if the user hasn't borrowed the specific currency defined by _reserve, it cannot be liquidated
(, vars.userCompoundedBorrowBalance, vars.borrowBalanceIncrease) = core
.getUserBorrowBalances(_reserve, _user);
if (vars.userCompoundedBorrowBalance == 0) {
return (
uint256(LiquidationErrors.CURRRENCY_NOT_BORROWED),
"User did not borrow the specified currency"
);
}
//all clear - calculate the max principal amount that can be liquidated
vars.maxPrincipalAmountToLiquidate = vars
.userCompoundedBorrowBalance
.mul(LIQUIDATION_CLOSE_FACTOR_PERCENT)
.div(100);
vars.actualAmountToLiquidate = _purchaseAmount > vars.maxPrincipalAmountToLiquidate
? vars.maxPrincipalAmountToLiquidate
: _purchaseAmount;
(uint256 maxCollateralToLiquidate, uint256 principalAmountNeeded) = calculateAvailableCollateralToLiquidate(
_collateral,
_reserve,
vars.actualAmountToLiquidate,
vars.userCollateralBalance
);
vars.originationFee = core.getUserOriginationFee(_reserve, _user);
//if there is a fee to liquidate, calculate the maximum amount of fee that can be liquidated
if (vars.originationFee > 0) {
(
vars.liquidatedCollateralForFee,
vars.feeLiquidated
) = calculateAvailableCollateralToLiquidate(
_collateral,
_reserve,
vars.originationFee,
vars.userCollateralBalance.sub(maxCollateralToLiquidate)
);
}
//if principalAmountNeeded < vars.ActualAmountToLiquidate, there isn't enough
//of _collateral to cover the actual amount that is being liquidated, hence we liquidate
//a smaller amount
if (principalAmountNeeded < vars.actualAmountToLiquidate) {
vars.actualAmountToLiquidate = principalAmountNeeded;
}
//if liquidator reclaims the underlying asset, we make sure there is enough available collateral in the reserve
if (!_receiveAToken) {
uint256 currentAvailableCollateral = core.getReserveAvailableLiquidity(_collateral);
if (currentAvailableCollateral < maxCollateralToLiquidate) {
return (
uint256(LiquidationErrors.NOT_ENOUGH_LIQUIDITY),
"There isn't enough liquidity available to liquidate"
);
}
}
core.updateStateOnLiquidation(
_reserve,
_collateral,
_user,
vars.actualAmountToLiquidate,
maxCollateralToLiquidate,
vars.feeLiquidated,
vars.liquidatedCollateralForFee,
vars.borrowBalanceIncrease,
_receiveAToken
);
AToken collateralAtoken = AToken(core.getReserveATokenAddress(_collateral));
//if liquidator reclaims the aToken, he receives the equivalent atoken amount
if (_receiveAToken) {
collateralAtoken.transferOnLiquidation(_user, msg.sender, maxCollateralToLiquidate);
} else {
//otherwise receives the underlying asset
//burn the equivalent amount of atoken
collateralAtoken.burnOnLiquidation(_user, maxCollateralToLiquidate);
core.transferToUser(_collateral, msg.sender, maxCollateralToLiquidate);
}
//transfers the principal currency to the pool
core.transferToReserve.value(msg.value)(_reserve, msg.sender, vars.actualAmountToLiquidate);
if (vars.feeLiquidated > 0) {
//if there is enough collateral to liquidate the fee, first transfer burn an equivalent amount of
//aTokens of the user
collateralAtoken.burnOnLiquidation(_user, vars.liquidatedCollateralForFee);
//then liquidate the fee by transferring it to the fee collection address
core.liquidateFee(
_collateral,
vars.liquidatedCollateralForFee,
addressesProvider.getTokenDistributor()
);
emit OriginationFeeLiquidated(
_collateral,
_reserve,
_user,
vars.feeLiquidated,
vars.liquidatedCollateralForFee,
//solium-disable-next-line
block.timestamp
);
}
emit LiquidationCall(
_collateral,
_reserve,
_user,
vars.actualAmountToLiquidate,
maxCollateralToLiquidate,
vars.borrowBalanceIncrease,
msg.sender,
_receiveAToken,
//solium-disable-next-line
block.timestamp
);
return (uint256(LiquidationErrors.NO_ERROR), "No errors");
}
struct AvailableCollateralToLiquidateLocalVars {
uint256 userCompoundedBorrowBalance;
uint256 liquidationBonus;
uint256 collateralPrice;
uint256 principalCurrencyPrice;
uint256 maxAmountCollateralToLiquidate;
}
/**
* @dev calculates how much of a specific collateral can be liquidated, given
* a certain amount of principal currency. This function needs to be called after
* all the checks to validate the liquidation have been performed, otherwise it might fail.
* @param _collateral the collateral to be liquidated
* @param _principal the principal currency to be liquidated
* @param _purchaseAmount the amount of principal being liquidated
* @param _userCollateralBalance the collatera balance for the specific _collateral asset of the user being liquidated
* @return the maximum amount that is possible to liquidated given all the liquidation constraints (user balance, close factor) and
* the purchase amount
**/
function calculateAvailableCollateralToLiquidate(
address _collateral,
address _principal,
uint256 _purchaseAmount,
uint256 _userCollateralBalance
) internal view returns (uint256 collateralAmount, uint256 principalAmountNeeded) {
collateralAmount = 0;
principalAmountNeeded = 0;
IPriceOracleGetter oracle = IPriceOracleGetter(addressesProvider.getPriceOracle());
// Usage of a memory struct of vars to avoid "Stack too deep" errors due to local variables
AvailableCollateralToLiquidateLocalVars memory vars;
vars.collateralPrice = oracle.getAssetPrice(_collateral);
vars.principalCurrencyPrice = oracle.getAssetPrice(_principal);
vars.liquidationBonus = core.getReserveLiquidationBonus(_collateral);
//this is the maximum possible amount of the selected collateral that can be liquidated, given the
//max amount of principal currency that is available for liquidation.
vars.maxAmountCollateralToLiquidate = vars
.principalCurrencyPrice
.mul(_purchaseAmount)
.div(vars.collateralPrice)
.mul(vars.liquidationBonus)
.div(100);
if (vars.maxAmountCollateralToLiquidate > _userCollateralBalance) {
collateralAmount = _userCollateralBalance;
principalAmountNeeded = vars
.collateralPrice
.mul(collateralAmount)
.div(vars.principalCurrencyPrice)
.mul(100)
.div(vars.liquidationBonus);
} else {
collateralAmount = vars.maxAmountCollateralToLiquidate;
principalAmountNeeded = _purchaseAmount;
}
return (collateralAmount, principalAmountNeeded);
}
}