Contract Name:
OneSplitAudit
Contract Source Code:
File 1 of 1 : OneSplitAudit
// File: @openzeppelin/contracts/GSN/Context.sol
pragma solidity ^0.5.0;
/*
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with GSN meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
contract Context {
// Empty internal constructor, to prevent people from mistakenly deploying
// an instance of this contract, which should be used via inheritance.
constructor () internal { }
// solhint-disable-previous-line no-empty-blocks
function _msgSender() internal view returns (address payable) {
return msg.sender;
}
function _msgData() internal view returns (bytes memory) {
this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
return msg.data;
}
}
// File: @openzeppelin/contracts/ownership/Ownable.sol
pragma solidity ^0.5.0;
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor () internal {
address msgSender = _msgSender();
_owner = msgSender;
emit OwnershipTransferred(address(0), msgSender);
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(isOwner(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Returns true if the caller is the current owner.
*/
function isOwner() public view returns (bool) {
return _msgSender() == _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;
}
}
// File: @openzeppelin/contracts/token/ERC20/IERC20.sol
pragma solidity ^0.5.0;
/**
* @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.
*
* IMPORTANT: 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);
}
// File: contracts/interface/IWETH.sol
pragma solidity ^0.5.0;
contract IWETH is IERC20 {
function deposit() external payable;
function withdraw(uint256 amount) external;
}
// File: @openzeppelin/contracts/math/SafeMath.sol
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) {
return sub(a, b, "SafeMath: subtraction overflow");
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*
* _Available since v2.4.0._
*/
function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b <= a, errorMessage);
uint256 c = a - b;
return c;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return div(a, b, "SafeMath: division by zero");
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts with custom message on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*
* _Available since v2.4.0._
*/
function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
// Solidity only automatically asserts when dividing by 0
require(b > 0, errorMessage);
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
return mod(a, b, "SafeMath: modulo by zero");
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts with custom message when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*
* _Available since v2.4.0._
*/
function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b != 0, errorMessage);
return a % b;
}
}
// File: @openzeppelin/contracts/utils/Address.sol
pragma solidity ^0.5.5;
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*/
function isContract(address account) internal view returns (bool) {
// According to EIP-1052, 0x0 is the value returned for not-yet created accounts
// and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
// for accounts without code, i.e. `keccak256('')`
bytes32 codehash;
bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
// solhint-disable-next-line no-inline-assembly
assembly { codehash := extcodehash(account) }
return (codehash != accountHash && codehash != 0x0);
}
/**
* @dev Converts an `address` into `address payable`. Note that this is
* simply a type cast: the actual underlying value is not changed.
*
* _Available since v2.4.0._
*/
function toPayable(address account) internal pure returns (address payable) {
return address(uint160(account));
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*
* _Available since v2.4.0._
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
// solhint-disable-next-line avoid-call-value
(bool success, ) = recipient.call.value(amount)("");
require(success, "Address: unable to send value, recipient may have reverted");
}
}
// File: @openzeppelin/contracts/token/ERC20/SafeERC20.sol
pragma solidity ^0.5.0;
/**
* @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, "SafeERC20: decreased allowance below zero");
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");
}
}
}
// File: contracts/UniversalERC20.sol
pragma solidity ^0.5.0;
library UniversalERC20 {
using SafeMath for uint256;
using SafeERC20 for IERC20;
IERC20 private constant ZERO_ADDRESS = IERC20(0x0000000000000000000000000000000000000000);
IERC20 private constant ETH_ADDRESS = IERC20(0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE);
function universalTransfer(IERC20 token, address to, uint256 amount) internal returns(bool) {
if (amount == 0) {
return true;
}
if (isETH(token)) {
address(uint160(to)).transfer(amount);
} else {
token.safeTransfer(to, amount);
return true;
}
}
function universalTransferFrom(IERC20 token, address from, address to, uint256 amount) internal {
if (amount == 0) {
return;
}
if (isETH(token)) {
require(from == msg.sender && msg.value >= amount, "Wrong useage of ETH.universalTransferFrom()");
if (to != address(this)) {
address(uint160(to)).transfer(amount);
}
if (msg.value > amount) {
msg.sender.transfer(msg.value.sub(amount));
}
} else {
token.safeTransferFrom(from, to, amount);
}
}
function universalTransferFromSenderToThis(IERC20 token, uint256 amount) internal {
if (amount == 0) {
return;
}
if (isETH(token)) {
if (msg.value > amount) {
// Return remainder if exist
msg.sender.transfer(msg.value.sub(amount));
}
} else {
token.safeTransferFrom(msg.sender, address(this), amount);
}
}
function universalApprove(IERC20 token, address to, uint256 amount) internal {
if (!isETH(token)) {
if (amount == 0) {
token.safeApprove(to, 0);
return;
}
uint256 allowance = token.allowance(address(this), to);
if (allowance < amount) {
if (allowance > 0) {
token.safeApprove(to, 0);
}
token.safeApprove(to, amount);
}
}
}
function universalBalanceOf(IERC20 token, address who) internal view returns (uint256) {
if (isETH(token)) {
return who.balance;
} else {
return token.balanceOf(who);
}
}
function universalDecimals(IERC20 token) internal view returns (uint256) {
if (isETH(token)) {
return 18;
}
(bool success, bytes memory data) = address(token).staticcall.gas(10000)(
abi.encodeWithSignature("decimals()")
);
if (!success || data.length == 0) {
(success, data) = address(token).staticcall.gas(10000)(
abi.encodeWithSignature("DECIMALS()")
);
}
return (success && data.length > 0) ? abi.decode(data, (uint256)) : 18;
}
function isETH(IERC20 token) internal pure returns(bool) {
return (address(token) == address(ZERO_ADDRESS) || address(token) == address(ETH_ADDRESS));
}
function notExist(IERC20 token) internal pure returns(bool) {
return (address(token) == address(-1));
}
}
// File: contracts/interface/IUniswapV2Exchange.sol
pragma solidity ^0.5.0;
interface IUniswapV2Exchange {
function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
}
library UniswapV2ExchangeLib {
using SafeMath for uint256;
using UniversalERC20 for IERC20;
function getReturn(
IUniswapV2Exchange exchange,
IERC20 fromToken,
IERC20 destToken,
uint amountIn
) internal view returns (uint256) {
uint256 reserveIn = fromToken.universalBalanceOf(address(exchange));
uint256 reserveOut = destToken.universalBalanceOf(address(exchange));
uint256 amountInWithFee = amountIn.mul(997);
uint256 numerator = amountInWithFee.mul(reserveOut);
uint256 denominator = reserveIn.mul(1000).add(amountInWithFee);
return (denominator == 0) ? 0 : numerator.div(denominator);
}
}
// File: contracts/IOneSplit.sol
pragma solidity ^0.5.0;
//
// [ msg.sender ]
// | |
// | |
// \_/
// +---------------+ ________________________________
// | OneSplitAudit | _______________________________ \
// +---------------+ \ \
// | | ______________ | | (staticcall)
// | | / ____________ \ | |
// | | (call) / / \ \ | |
// | | / / | | | |
// \_/ | | \_/ \_/
// +--------------+ | | +----------------------+
// | OneSplitWrap | | | | OneSplitViewWrap |
// +--------------+ | | +----------------------+
// | | | | | |
// | | (delegatecall) | | (staticcall) | | (staticcall)
// \_/ | | \_/
// +--------------+ | | +------------------+
// | OneSplit | | | | OneSplitView |
// +--------------+ | | +------------------+
// | | / /
// \ \________________/ /
// \__________________/
//
contract IOneSplitConsts {
// flags = FLAG_DISABLE_UNISWAP + FLAG_DISABLE_BANCOR + ...
uint256 internal constant FLAG_DISABLE_UNISWAP = 0x01;
uint256 internal constant DEPRECATED_FLAG_DISABLE_KYBER = 0x02; // Deprecated
uint256 internal constant FLAG_DISABLE_BANCOR = 0x04;
uint256 internal constant FLAG_DISABLE_OASIS = 0x08;
uint256 internal constant FLAG_DISABLE_COMPOUND = 0x10;
uint256 internal constant FLAG_DISABLE_FULCRUM = 0x20;
uint256 internal constant FLAG_DISABLE_CHAI = 0x40;
uint256 internal constant FLAG_DISABLE_AAVE = 0x80;
uint256 internal constant FLAG_DISABLE_SMART_TOKEN = 0x100;
uint256 internal constant DEPRECATED_FLAG_ENABLE_MULTI_PATH_ETH = 0x200; // Deprecated, Turned off by default
uint256 internal constant FLAG_DISABLE_BDAI = 0x400;
uint256 internal constant FLAG_DISABLE_IEARN = 0x800;
uint256 internal constant FLAG_DISABLE_CURVE_COMPOUND = 0x1000;
uint256 internal constant FLAG_DISABLE_CURVE_USDT = 0x2000;
uint256 internal constant FLAG_DISABLE_CURVE_Y = 0x4000;
uint256 internal constant FLAG_DISABLE_CURVE_BINANCE = 0x8000;
uint256 internal constant DEPRECATED_FLAG_ENABLE_MULTI_PATH_DAI = 0x10000; // Deprecated, Turned off by default
uint256 internal constant DEPRECATED_FLAG_ENABLE_MULTI_PATH_USDC = 0x20000; // Deprecated, Turned off by default
uint256 internal constant FLAG_DISABLE_CURVE_SYNTHETIX = 0x40000;
uint256 internal constant FLAG_DISABLE_WETH = 0x80000;
uint256 internal constant FLAG_DISABLE_UNISWAP_COMPOUND = 0x100000; // Works only when one of assets is ETH or FLAG_ENABLE_MULTI_PATH_ETH
uint256 internal constant FLAG_DISABLE_UNISWAP_CHAI = 0x200000; // Works only when ETH<>DAI or FLAG_ENABLE_MULTI_PATH_ETH
uint256 internal constant FLAG_DISABLE_UNISWAP_AAVE = 0x400000; // Works only when one of assets is ETH or FLAG_ENABLE_MULTI_PATH_ETH
uint256 internal constant FLAG_DISABLE_IDLE = 0x800000;
uint256 internal constant FLAG_DISABLE_MOONISWAP = 0x1000000;
uint256 internal constant FLAG_DISABLE_UNISWAP_V2 = 0x2000000;
uint256 internal constant FLAG_DISABLE_UNISWAP_V2_ETH = 0x4000000;
uint256 internal constant FLAG_DISABLE_UNISWAP_V2_DAI = 0x8000000;
uint256 internal constant FLAG_DISABLE_UNISWAP_V2_USDC = 0x10000000;
uint256 internal constant FLAG_DISABLE_ALL_SPLIT_SOURCES = 0x20000000;
uint256 internal constant FLAG_DISABLE_ALL_WRAP_SOURCES = 0x40000000;
uint256 internal constant FLAG_DISABLE_CURVE_PAX = 0x80000000;
uint256 internal constant FLAG_DISABLE_CURVE_RENBTC = 0x100000000;
uint256 internal constant FLAG_DISABLE_CURVE_TBTC = 0x200000000;
uint256 internal constant DEPRECATED_FLAG_ENABLE_MULTI_PATH_USDT = 0x400000000; // Deprecated, Turned off by default
uint256 internal constant DEPRECATED_FLAG_ENABLE_MULTI_PATH_WBTC = 0x800000000; // Deprecated, Turned off by default
uint256 internal constant DEPRECATED_FLAG_ENABLE_MULTI_PATH_TBTC = 0x1000000000; // Deprecated, Turned off by default
uint256 internal constant DEPRECATED_FLAG_ENABLE_MULTI_PATH_RENBTC = 0x2000000000; // Deprecated, Turned off by default
uint256 internal constant FLAG_DISABLE_DFORCE_SWAP = 0x4000000000;
uint256 internal constant FLAG_DISABLE_SHELL = 0x8000000000;
uint256 internal constant FLAG_ENABLE_CHI_BURN = 0x10000000000;
uint256 internal constant FLAG_DISABLE_MSTABLE_MUSD = 0x20000000000;
uint256 internal constant FLAG_DISABLE_CURVE_SBTC = 0x40000000000;
uint256 internal constant FLAG_DISABLE_DMM = 0x80000000000;
uint256 internal constant FLAG_DISABLE_UNISWAP_ALL = 0x100000000000;
uint256 internal constant FLAG_DISABLE_CURVE_ALL = 0x200000000000;
uint256 internal constant FLAG_DISABLE_UNISWAP_V2_ALL = 0x400000000000;
uint256 internal constant FLAG_DISABLE_SPLIT_RECALCULATION = 0x800000000000;
uint256 internal constant FLAG_DISABLE_BALANCER_ALL = 0x1000000000000;
uint256 internal constant FLAG_DISABLE_BALANCER_1 = 0x2000000000000;
uint256 internal constant FLAG_DISABLE_BALANCER_2 = 0x4000000000000;
uint256 internal constant FLAG_DISABLE_BALANCER_3 = 0x8000000000000;
uint256 internal constant DEPRECATED_FLAG_ENABLE_KYBER_UNISWAP_RESERVE = 0x10000000000000; // Deprecated, Turned off by default
uint256 internal constant DEPRECATED_FLAG_ENABLE_KYBER_OASIS_RESERVE = 0x20000000000000; // Deprecated, Turned off by default
uint256 internal constant DEPRECATED_FLAG_ENABLE_KYBER_BANCOR_RESERVE = 0x40000000000000; // Deprecated, Turned off by default
uint256 internal constant FLAG_ENABLE_REFERRAL_GAS_SPONSORSHIP = 0x80000000000000; // Turned off by default
uint256 internal constant DEPRECATED_FLAG_ENABLE_MULTI_PATH_COMP = 0x100000000000000; // Deprecated, Turned off by default
uint256 internal constant FLAG_DISABLE_KYBER_ALL = 0x200000000000000;
uint256 internal constant FLAG_DISABLE_KYBER_1 = 0x400000000000000;
uint256 internal constant FLAG_DISABLE_KYBER_2 = 0x800000000000000;
uint256 internal constant FLAG_DISABLE_KYBER_3 = 0x1000000000000000;
uint256 internal constant FLAG_DISABLE_KYBER_4 = 0x2000000000000000;
uint256 internal constant FLAG_ENABLE_CHI_BURN_BY_ORIGIN = 0x4000000000000000;
}
contract IOneSplit is IOneSplitConsts {
function getExpectedReturn(
IERC20 fromToken,
IERC20 destToken,
uint256 amount,
uint256 parts,
uint256 flags // See constants in IOneSplit.sol
)
public
view
returns(
uint256 returnAmount,
uint256[] memory distribution
);
function getExpectedReturnWithGas(
IERC20 fromToken,
IERC20 destToken,
uint256 amount,
uint256 parts,
uint256 flags, // See constants in IOneSplit.sol
uint256 destTokenEthPriceTimesGasPrice
)
public
view
returns(
uint256 returnAmount,
uint256 estimateGasAmount,
uint256[] memory distribution
);
function swap(
IERC20 fromToken,
IERC20 destToken,
uint256 amount,
uint256 minReturn,
uint256[] memory distribution,
uint256 flags
)
public
payable
returns(uint256 returnAmount);
}
contract IOneSplitMulti is IOneSplit {
function getExpectedReturnWithGasMulti(
IERC20[] memory tokens,
uint256 amount,
uint256[] memory parts,
uint256[] memory flags,
uint256[] memory destTokenEthPriceTimesGasPrices
)
public
view
returns(
uint256[] memory returnAmounts,
uint256 estimateGasAmount,
uint256[] memory distribution
);
function swapMulti(
IERC20[] memory tokens,
uint256 amount,
uint256 minReturn,
uint256[] memory distribution,
uint256[] memory flags
)
public
payable
returns(uint256 returnAmount);
}
// File: contracts/OneSplitAudit.sol
pragma solidity ^0.5.0;
contract IFreeFromUpTo is IERC20 {
function freeFromUpTo(address from, uint256 value) external returns(uint256 freed);
}
interface IReferralGasSponsor {
function makeGasDiscount(
uint256 gasSpent,
uint256 returnAmount,
bytes calldata msgSenderCalldata
) external;
}
library Array {
function first(IERC20[] memory arr) internal pure returns(IERC20) {
return arr[0];
}
function last(IERC20[] memory arr) internal pure returns(IERC20) {
return arr[arr.length - 1];
}
}
//
// Security assumptions:
// 1. It is safe to have infinite approves of any tokens to this smart contract,
// since it could only call `transferFrom()` with first argument equal to msg.sender
// 2. It is safe to call `swap()` with reliable `minReturn` argument,
// if returning amount will not reach `minReturn` value whole swap will be reverted.
// 3. Additionally CHI tokens could be burned from caller in case of FLAG_ENABLE_CHI_BURN (0x10000000000)
// presented in `flags` or from transaction origin in case of FLAG_ENABLE_CHI_BURN_BY_ORIGIN (0x4000000000000000)
// presented in `flags`. Burned amount would refund up to 43% of gas fees.
//
contract OneSplitAudit is IOneSplit, Ownable {
using SafeMath for uint256;
using UniversalERC20 for IERC20;
using Array for IERC20[];
IWETH constant internal weth = IWETH(0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2);
IFreeFromUpTo public constant chi = IFreeFromUpTo(0x0000000000004946c0e9F43F4Dee607b0eF1fA1c);
IOneSplitMulti public oneSplitImpl;
event ImplementationUpdated(address indexed newImpl);
event Swapped(
IERC20 indexed fromToken,
IERC20 indexed destToken,
uint256 fromTokenAmount,
uint256 destTokenAmount,
uint256 minReturn,
uint256[] distribution,
uint256[] flags,
address referral,
uint256 feePercent
);
constructor(IOneSplitMulti impl) public {
setNewImpl(impl);
}
function() external payable {
// solium-disable-next-line security/no-tx-origin
require(msg.sender != tx.origin, "OneSplit: do not send ETH directly");
}
function setNewImpl(IOneSplitMulti impl) public onlyOwner {
oneSplitImpl = impl;
emit ImplementationUpdated(address(impl));
}
/// @notice Calculate expected returning amount of `destToken`
/// @param fromToken (IERC20) Address of token or `address(0)` for Ether
/// @param destToken (IERC20) Address of token or `address(0)` for Ether
/// @param amount (uint256) Amount for `fromToken`
/// @param parts (uint256) Number of pieces source volume could be splitted,
/// works like granularity, higly affects gas usage. Should be called offchain,
/// but could be called onchain if user swaps not his own funds, but this is still considered as not safe.
/// @param flags (uint256) Flags for enabling and disabling some features, default 0
function getExpectedReturn(
IERC20 fromToken,
IERC20 destToken,
uint256 amount,
uint256 parts,
uint256 flags // See contants in IOneSplit.sol
)
public
view
returns(
uint256 returnAmount,
uint256[] memory distribution
)
{
(returnAmount, , distribution) = getExpectedReturnWithGas(
fromToken,
destToken,
amount,
parts,
flags,
0
);
}
/// @notice Calculate expected returning amount of `destToken`
/// @param fromToken (IERC20) Address of token or `address(0)` for Ether
/// @param destToken (IERC20) Address of token or `address(0)` for Ether
/// @param amount (uint256) Amount for `fromToken`
/// @param parts (uint256) Number of pieces source volume could be splitted,
/// works like granularity, higly affects gas usage. Should be called offchain,
/// but could be called onchain if user swaps not his own funds, but this is still considered as not safe.
/// @param flags (uint256) Flags for enabling and disabling some features, default 0
/// @param destTokenEthPriceTimesGasPrice (uint256) destToken price to ETH multiplied by gas price
function getExpectedReturnWithGas(
IERC20 fromToken,
IERC20 destToken,
uint256 amount,
uint256 parts,
uint256 flags, // See constants in IOneSplit.sol
uint256 destTokenEthPriceTimesGasPrice
)
public
view
returns(
uint256 returnAmount,
uint256 estimateGasAmount,
uint256[] memory distribution
)
{
return oneSplitImpl.getExpectedReturnWithGas(
fromToken,
destToken,
amount,
parts,
flags,
destTokenEthPriceTimesGasPrice
);
}
/// @notice Calculate expected returning amount of first `tokens` element to
/// last `tokens` element through ann the middle tokens with corresponding
/// `parts`, `flags` and `destTokenEthPriceTimesGasPrices` array values of each step
/// @param tokens (IERC20[]) Address of token or `address(0)` for Ether
/// @param amount (uint256) Amount for `fromToken`
/// @param parts (uint256[]) Number of pieces source volume could be splitted
/// @param flags (uint256[]) Flags for enabling and disabling some features, default 0
/// @param destTokenEthPriceTimesGasPrices (uint256[]) destToken price to ETH multiplied by gas price
function getExpectedReturnWithGasMulti(
IERC20[] memory tokens,
uint256 amount,
uint256[] memory parts,
uint256[] memory flags,
uint256[] memory destTokenEthPriceTimesGasPrices
)
public
view
returns(
uint256[] memory returnAmounts,
uint256 estimateGasAmount,
uint256[] memory distribution
)
{
return oneSplitImpl.getExpectedReturnWithGasMulti(
tokens,
amount,
parts,
flags,
destTokenEthPriceTimesGasPrices
);
}
/// @notice Swap `amount` of `fromToken` to `destToken`
/// @param fromToken (IERC20) Address of token or `address(0)` for Ether
/// @param destToken (IERC20) Address of token or `address(0)` for Ether
/// @param amount (uint256) Amount for `fromToken`
/// @param minReturn (uint256) Minimum expected return, else revert
/// @param distribution (uint256[]) Array of weights for volume distribution returned by `getExpectedReturn`
/// @param flags (uint256) Flags for enabling and disabling some features, default 0
function swap(
IERC20 fromToken,
IERC20 destToken,
uint256 amount,
uint256 minReturn,
uint256[] memory distribution,
uint256 flags // See contants in IOneSplit.sol
) public payable returns(uint256) {
return swapWithReferral(
fromToken,
destToken,
amount,
minReturn,
distribution,
flags,
address(0),
0
);
}
/// @notice Swap `amount` of `fromToken` to `destToken`
/// param fromToken (IERC20) Address of token or `address(0)` for Ether
/// param destToken (IERC20) Address of token or `address(0)` for Ether
/// @param amount (uint256) Amount for `fromToken`
/// @param minReturn (uint256) Minimum expected return, else revert
/// @param distribution (uint256[]) Array of weights for volume distribution returned by `getExpectedReturn`
/// @param flags (uint256) Flags for enabling and disabling some features, default 0
/// @param referral (address) Address of referral
/// @param feePercent (uint256) Fees percents normalized to 1e18, limited to 0.03e18 (3%)
function swapWithReferral(
IERC20 fromToken,
IERC20 destToken,
uint256 amount,
uint256 minReturn,
uint256[] memory distribution,
uint256 flags, // See contants in IOneSplit.sol
address referral,
uint256 feePercent
) public payable returns(uint256) {
IERC20[] memory tokens = new IERC20[](2);
tokens[0] = fromToken;
tokens[1] = destToken;
uint256[] memory flagsArray = new uint256[](1);
flagsArray[0] = flags;
swapWithReferralMulti(
tokens,
amount,
minReturn,
distribution,
flagsArray,
referral,
feePercent
);
}
/// @notice Swap `amount` of first element of `tokens` to the latest element of `destToken`
/// @param tokens (IERC20[]) Addresses of token or `address(0)` for Ether
/// @param amount (uint256) Amount for `fromToken`
/// @param minReturn (uint256) Minimum expected return, else revert
/// @param distribution (uint256[]) Array of weights for volume distribution returned by `getExpectedReturn`
/// @param flags (uint256[]) Flags for enabling and disabling some features, default 0
function swapMulti(
IERC20[] memory tokens,
uint256 amount,
uint256 minReturn,
uint256[] memory distribution,
uint256[] memory flags
) public payable returns(uint256) {
swapWithReferralMulti(
tokens,
amount,
minReturn,
distribution,
flags,
address(0),
0
);
}
/// @notice Swap `amount` of first element of `tokens` to the latest element of `destToken`
/// @param tokens (IERC20[]) Addresses of token or `address(0)` for Ether
/// @param amount (uint256) Amount for `fromToken`
/// @param minReturn (uint256) Minimum expected return, else revert
/// @param distribution (uint256[]) Array of weights for volume distribution returned by `getExpectedReturn`
/// @param flags (uint256[]) Flags for enabling and disabling some features, default 0
/// @param referral (address) Address of referral
/// @param feePercent (uint256) Fees percents normalized to 1e18, limited to 0.03e18 (3%)
function swapWithReferralMulti(
IERC20[] memory tokens,
uint256 amount,
uint256 minReturn,
uint256[] memory distribution,
uint256[] memory flags,
address referral,
uint256 feePercent
) public payable returns(uint256 returnAmount) {
require(tokens.length >= 2 && amount > 0, "OneSplit: swap makes no sense");
require(flags.length == tokens.length - 1, "OneSplit: flags array length is invalid");
require((msg.value != 0) == tokens.first().isETH(), "OneSplit: msg.value should be used only for ETH swap");
require(feePercent <= 0.03e18, "OneSplit: feePercent out of range");
uint256 gasStart = gasleft();
Balances memory beforeBalances = _getFirstAndLastBalances(tokens, true);
// Transfer From
tokens.first().universalTransferFromSenderToThis(amount);
uint256 confirmed = tokens.first().universalBalanceOf(address(this)).sub(beforeBalances.ofFromToken);
// Swap
tokens.first().universalApprove(address(oneSplitImpl), confirmed);
oneSplitImpl.swapMulti.value(tokens.first().isETH() ? confirmed : 0)(
tokens,
confirmed,
minReturn,
distribution,
flags
);
Balances memory afterBalances = _getFirstAndLastBalances(tokens, false);
// Return
returnAmount = afterBalances.ofDestToken.sub(beforeBalances.ofDestToken);
require(returnAmount >= minReturn, "OneSplit: actual return amount is less than minReturn");
tokens.last().universalTransfer(referral, returnAmount.mul(feePercent).div(1e18));
tokens.last().universalTransfer(msg.sender, returnAmount.sub(returnAmount.mul(feePercent).div(1e18)));
emit Swapped(
tokens.first(),
tokens.last(),
amount,
returnAmount,
minReturn,
distribution,
flags,
referral,
feePercent
);
// Return remainder
if (afterBalances.ofFromToken > beforeBalances.ofFromToken) {
tokens.first().universalTransfer(msg.sender, afterBalances.ofFromToken.sub(beforeBalances.ofFromToken));
}
if ((flags[0] & (FLAG_ENABLE_CHI_BURN | FLAG_ENABLE_CHI_BURN_BY_ORIGIN)) > 0) {
uint256 gasSpent = 21000 + gasStart - gasleft() + 16 * msg.data.length;
_chiBurnOrSell(
((flags[0] & FLAG_ENABLE_CHI_BURN_BY_ORIGIN) > 0) ? tx.origin : msg.sender,
(gasSpent + 14154) / 41947
);
}
else if ((flags[0] & FLAG_ENABLE_REFERRAL_GAS_SPONSORSHIP) > 0) {
uint256 gasSpent = 21000 + gasStart - gasleft() + 16 * msg.data.length;
IReferralGasSponsor(referral).makeGasDiscount(gasSpent, returnAmount, msg.data);
}
}
function claimAsset(IERC20 asset, uint256 amount) public onlyOwner {
asset.universalTransfer(msg.sender, amount);
}
function _chiBurnOrSell(address payable sponsor, uint256 amount) internal {
IUniswapV2Exchange exchange = IUniswapV2Exchange(0xa6f3ef841d371a82ca757FaD08efc0DeE2F1f5e2);
uint256 sellRefund = UniswapV2ExchangeLib.getReturn(exchange, chi, weth, amount);
uint256 burnRefund = amount.mul(18_000).mul(tx.gasprice);
if (sellRefund < burnRefund.add(tx.gasprice.mul(36_000))) {
chi.freeFromUpTo(sponsor, amount);
}
else {
chi.transferFrom(sponsor, address(exchange), amount);
exchange.swap(0, sellRefund, address(this), "");
weth.withdraw(weth.balanceOf(address(this)));
sponsor.transfer(address(this).balance);
}
}
struct Balances {
uint256 ofFromToken;
uint256 ofDestToken;
}
function _getFirstAndLastBalances(IERC20[] memory tokens, bool subValue) internal view returns(Balances memory) {
return Balances({
ofFromToken: tokens.first().universalBalanceOf(address(this)).sub(subValue ? msg.value : 0),
ofDestToken: tokens.last().universalBalanceOf(address(this))
});
}
}