Contract Name:
O3EthereumUniswapV3Aggregator
Contract Source Code:
// SPDX-License-Identifier: AGPL-3.0
pragma solidity ^0.8.0;
import "../../access/Ownable.sol";
import "../../swap/interfaces/IPool.sol";
import "../../assets/interfaces/IWETH.sol";
import "../interfaces/IUniswapV3SwapRouter.sol";
import "../../crossChain/interfaces/IWrapper.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
contract O3EthereumUniswapV3Aggregator is Ownable {
using SafeERC20 for IERC20;
event LOG_AGG_SWAP (
uint256 amountOut,
uint256 fee
);
address public WETH = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
address public router = 0x68b3465833fb72A70ecDF485E0e4C7bD8665Fc45;
address public O3Wrapper = 0xeCF2B548e5c21028B0b60363207700fA421B6EcB;
address public feeCollector;
constructor (address _feeCollector) {
require(_feeCollector != address(0), 'feeCollector address cannot be zero');
feeCollector = _feeCollector;
}
modifier ensure(uint deadline) {
require(deadline >= block.timestamp, 'O3Aggregator: EXPIRED');
_;
}
receive() external payable { }
function setWETH(address _weth) external onlyOwner {
require(_weth != address(0), 'WETH address cannot be zero');
WETH = _weth;
}
function setRouter(address _router) external onlyOwner {
require(_router != address(0), 'router address cannot be zero');
router = _router;
}
function setO3Wrapper(address _wrapper) external onlyOwner {
require(_wrapper != address(0), 'wrapper address cannot be zero');
O3Wrapper = _wrapper;
}
function setFeeCollector(address _feeCollector) external onlyOwner {
require(_feeCollector != address(0), 'feeCollector address cannot be zero');
feeCollector = _feeCollector;
}
function rescueFund(address tokenAddress) external onlyOwner {
IERC20 token = IERC20(tokenAddress);
if (tokenAddress == WETH && address(this).balance > 0) {
(bool success,) = _msgSender().call{value: address(this).balance}(new bytes(0));
require(success, 'ETH_TRANSFER_FAILED');
}
token.safeTransfer(_msgSender(), token.balanceOf(address(this)));
}
function exactInputSinglePToken(
uint256 amountIn,
address poolAddress,
uint poolAmountOutMin,
address[] calldata path,
uint24 v3PoolFee,
address to,
uint deadline,
uint aggSwapAmountOutMin,
bool unwrapETH
) external ensure(deadline) {
if (amountIn == 0) {
amountIn = IERC20(path[0]).allowance(_msgSender(), address(this));
}
require(amountIn != 0, 'O3Aggregator: ZERO_AMOUNT_IN');
IERC20(path[0]).safeTransferFrom(_msgSender(), address(this), amountIn);
{
IERC20(path[0]).safeApprove(poolAddress, amountIn);
require(address(IPool(poolAddress).coins(0)) == path[1], "O3Aggregator: INVALID_PATH");
uint balanceBefore = IERC20(path[1]).balanceOf(address(this));
IPool(poolAddress).swap(1, 0, amountIn, poolAmountOutMin, deadline);
amountIn = IERC20(path[1]).balanceOf(address(this)) - balanceBefore;
}
require(path.length >= 3, 'O3Aggregator: INVALID_PATH');
IUniswapV3SwapRouter.ExactInputSingleParams memory params = IUniswapV3SwapRouter.ExactInputSingleParams(
path[1], path[path.length-1], v3PoolFee, address(this), amountIn, aggSwapAmountOutMin, 0
);
(uint amountOut, uint feeAmount, ) = _swap(params);
if (unwrapETH) {
require(params.tokenOut == WETH, 'O3Aggregator: INVALID_TOKEN_OUT');
IWETH(WETH).withdraw(amountOut);
_sendETH(to, amountOut - feeAmount);
_sendETH(feeCollector, feeAmount);
} else {
IERC20(params.tokenOut).safeTransfer(to, amountOut - feeAmount);
IERC20(params.tokenOut).safeTransfer(feeCollector, feeAmount);
}
}
function exactInputSingle(
IUniswapV3SwapRouter.ExactInputSingleParams memory params,
bool unwrapETH,
uint deadline
) external payable ensure(deadline) {
_pull(params.tokenIn, params.amountIn, 0);
(uint amountOut, uint feeAmount, address receiver) = _swap(params);
if (unwrapETH) {
require(params.tokenOut == WETH, 'O3Aggregator: INVALID_TOKEN_OUT');
IWETH(WETH).withdraw(amountOut);
_sendETH(receiver, amountOut - feeAmount);
_sendETH(feeCollector, feeAmount);
} else {
IERC20(params.tokenOut).safeTransfer(receiver, amountOut - feeAmount);
IERC20(params.tokenOut).safeTransfer(feeCollector, feeAmount);
}
}
function _pull(address token, uint amountIn, uint netFee) internal {
if (msg.value - netFee > 0) {
require(token == WETH, 'O3Aggregator: INVALID_TOKEN_IN');
IWETH(WETH).deposit{value: msg.value - netFee}();
} else {
require(amountIn > 0, 'O3Aggregator: INSUFFICIENT_INPUT_AMOUNT');
IERC20(token).safeTransferFrom(msg.sender, address(this), amountIn);
}
}
function _swap(IUniswapV3SwapRouter.ExactInputSingleParams memory params) internal returns (uint, uint, address) {
require(params.recipient != address(0), 'O3Aggregator: INVALID_RECIPIENT');
address receiver = params.recipient;
params.recipient = address(this);
IERC20(params.tokenIn).safeApprove(router, params.amountIn);
uint balanceBefore = IERC20(params.tokenOut).balanceOf(address(this));
IUniswapV3SwapRouter(router).exactInputSingle(params);
uint amountOut = IERC20(params.tokenOut).balanceOf(address(this)) - balanceBefore;
uint feeAmount = amountOut * params.fee / 1000000;
emit LOG_AGG_SWAP(amountOut, feeAmount);
return (amountOut, feeAmount, receiver);
}
function exactInputSingleCrossChain(
IUniswapV3SwapRouter.ExactInputSingleParams memory params,
address poolAddress, address tokenTo, uint256 minDy, uint256 deadline, // args for swap
uint fee, uint64 toChainId, bytes memory callData // args for wrapper
) external payable ensure(deadline) {
_pull(params.tokenIn, params.amountIn, fee);
uint swapperAmountIn;
address receiver;
{
uint amountOut;
uint feeAmount;
(amountOut, feeAmount, receiver) = _swap(params);
IERC20(params.tokenOut).safeTransfer(feeCollector, feeAmount);
swapperAmountIn = amountOut - feeAmount;
}
IERC20(params.tokenOut).safeApprove(O3Wrapper, swapperAmountIn);
IWrapper(O3Wrapper).swapAndBridgeOut{value: fee}(
poolAddress, params.tokenOut, tokenTo, swapperAmountIn, minDy, deadline,
toChainId, abi.encodePacked(receiver), callData
);
}
function _sendETH(address to, uint256 amount) internal {
(bool success,) = to.call{value:amount}(new bytes(0));
require(success, 'O3Aggregator: ETH_TRANSFER_FAILED');
}
}
// SPDX-License-Identifier: AGPL-3.0
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
interface IPool {
function coins(uint256 index) external view returns(IERC20);
function getA() external view returns (uint256);
function getTokenIndex(address token) external view returns (uint8);
function getVirtualPrice() external view returns (uint256);
function calculateSwap(uint8 tokenIndexFrom, uint8 tokenIndexTo, uint256 dx) external view returns (uint256 dy);
function calculateRemoveLiquidity(uint256 amount) external view returns (uint256[] memory);
function calculateTokenAmount(uint256[] calldata amounts, bool deposit) external view returns (uint256);
function calculateWithdrawOneToken(uint256 tokenAmount, uint8 tokenIndex) external view returns (uint256 amount);
function swap(uint8 tokenIndexFrom, uint8 tokenIndexTo, uint256 dx, uint256 minDy, uint256 deadline) external returns (uint256);
function addLiquidity(uint256[] memory amounts, uint256 minToMint, uint256 deadline) external returns (uint256);
function removeLiquidity(uint256 amount, uint256[] calldata minAmounts, uint256 deadline) external returns (uint256[] memory);
function removeLiquidityOneToken(uint256 tokenAmount, uint8 tokenIndex, uint256 minAmount, uint256 deadline) external returns (uint256);
function removeLiquidityImbalance(uint256[] calldata amounts, uint256 maxBurnAmount, uint256 deadline) external returns (uint256);
function applySwapFee(uint256 newSwapFee) external;
function applyAdminFee(uint256 newAdminFee) external;
function getAdminBalance(uint256 index) external view returns (uint256);
function withdrawAdminFee(address receiver) external;
function rampA(uint256 _futureA, uint256 _futureTime) external;
function stopRampA() external;
}
// SPDX-License-Identifier: AGPL-3.0
pragma solidity ^0.8.0;
interface IWrapper {
function bridgeOut(
address pTokenAddress,
uint256 amount,
uint64 toChainId,
bytes memory toAddress,
bytes memory callData
) external payable returns(bool);
function swapAndBridgeOut(
address poolAddress, address tokenFrom, address tokenTo, uint256 dx, uint256 minDy, uint256 deadline, // args for swap
uint64 toChainId, bytes memory toAddress, bytes memory callData // args for bridge
) external payable returns(bool);
function swapAndBridgeOutNativeToken(
address poolAddress, address tokenTo, uint256 dx, uint256 minDy, uint256 deadline, // args for swap
uint64 toChainId, bytes memory toAddress, bytes memory callData // args for bridge
) external payable returns(bool);
function depositAndBridgeOut(
address originalToken,
address pTokenAddress,
uint256 amount,
uint64 toChainId,
bytes memory toAddress,
bytes memory callData
) external payable returns(bool);
function depositAndBridgeOutNativeToken(
address pTokenAddress,
uint256 amount,
uint64 toChainId,
bytes memory toAddress,
bytes memory callData
) external payable returns(bool);
function bridgeOutAndWithdraw(
address pTokenAddress,
uint64 toChainId,
bytes memory toAddress,
uint256 amount
) external payable returns(bool);
}
// SPDX-License-Identifier: AGPL-3.0
pragma solidity ^0.8.0;
interface IWETH {
function deposit() external payable;
function withdraw(uint wad) external;
function transfer(address dst, uint wad) external returns (bool);
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.5;
pragma abicoder v2;
/// @title Callback for IUniswapV3PoolActions#swap
/// @notice Any contract that calls IUniswapV3PoolActions#swap must implement this interface
interface IUniswapV3SwapCallback {
/// @notice Called to `msg.sender` after executing a swap via IUniswapV3Pool#swap.
/// @dev In the implementation you must pay the pool tokens owed for the swap.
/// The caller of this method must be checked to be a UniswapV3Pool deployed by the canonical UniswapV3Factory.
/// amount0Delta and amount1Delta can both be 0 if no tokens were swapped.
/// @param amount0Delta The amount of token0 that was sent (negative) or must be received (positive) by the pool by
/// the end of the swap. If positive, the callback must send that amount of token0 to the pool.
/// @param amount1Delta The amount of token1 that was sent (negative) or must be received (positive) by the pool by
/// the end of the swap. If positive, the callback must send that amount of token1 to the pool.
/// @param data Any data passed through by the caller via the IUniswapV3PoolActions#swap call
function uniswapV3SwapCallback(
int256 amount0Delta,
int256 amount1Delta,
bytes calldata data
) external;
}
/// @title Router token swapping functionality
/// @notice Functions for swapping tokens via Uniswap V3
interface IUniswapV3SwapRouter is IUniswapV3SwapCallback {
struct ExactInputSingleParams {
address tokenIn;
address tokenOut;
uint24 fee;
address recipient;
uint256 amountIn;
uint256 amountOutMinimum;
uint160 sqrtPriceLimitX96;
}
/// @notice Swaps `amountIn` of one token for as much as possible of another token
/// @dev Setting `amountIn` to 0 will cause the contract to look up its own balance,
/// and swap the entire amount, enabling contracts to send tokens before calling this function.
/// @param params The parameters necessary for the swap, encoded as `ExactInputSingleParams` in calldata
/// @return amountOut The amount of the received token
function exactInputSingle(ExactInputSingleParams calldata params) external payable returns (uint256 amountOut);
struct ExactInputParams {
bytes path;
address recipient;
uint256 amountIn;
uint256 amountOutMinimum;
}
/// @notice Swaps `amountIn` of one token for as much as possible of another along the specified path
/// @dev Setting `amountIn` to 0 will cause the contract to look up its own balance,
/// and swap the entire amount, enabling contracts to send tokens before calling this function.
/// @param params The parameters necessary for the multi-hop swap, encoded as `ExactInputParams` in calldata
/// @return amountOut The amount of the received token
function exactInput(ExactInputParams calldata params) external payable returns (uint256 amountOut);
struct ExactOutputSingleParams {
address tokenIn;
address tokenOut;
uint24 fee;
address recipient;
uint256 amountOut;
uint256 amountInMaximum;
uint160 sqrtPriceLimitX96;
}
/// @notice Swaps as little as possible of one token for `amountOut` of another token
/// that may remain in the router after the swap.
/// @param params The parameters necessary for the swap, encoded as `ExactOutputSingleParams` in calldata
/// @return amountIn The amount of the input token
function exactOutputSingle(ExactOutputSingleParams calldata params) external payable returns (uint256 amountIn);
struct ExactOutputParams {
bytes path;
address recipient;
uint256 amountOut;
uint256 amountInMaximum;
}
/// @notice Swaps as little as possible of one token for `amountOut` of another along the specified path (reversed)
/// that may remain in the router after the swap.
/// @param params The parameters necessary for the multi-hop swap, encoded as `ExactOutputParams` in calldata
/// @return amountIn The amount of the input token
function exactOutput(ExactOutputParams calldata params) external payable returns (uint256 amountIn);
}
// SPDX-License-Identifier: AGPL-3.0
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/utils/Context.sol";
/**
* @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.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* 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.
*/
abstract 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() {
_transferOwnership(_msgSender());
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
* @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 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.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
pragma solidity ^0.8.1;
/**
* @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
* ====
*
* [IMPORTANT]
* ====
* You shouldn't rely on `isContract` to protect against flash loan attacks!
*
* Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
* like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
* constructor.
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize/address.code.length, which returns 0
// for contracts in construction, since the code is only stored at the end
// of the constructor execution.
return account.code.length > 0;
}
/**
* @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].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value
) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
(bool success, bytes memory returndata) = target.call{value: value}(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(
address target,
bytes memory data,
string memory errorMessage
) internal view returns (bytes memory) {
require(isContract(target), "Address: static call to non-contract");
(bool success, bytes memory returndata) = target.staticcall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
require(isContract(target), "Address: delegate call to non-contract");
(bool success, bytes memory returndata) = target.delegatecall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason using the provided one.
*
* _Available since v4.3._
*/
function verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) internal pure returns (bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
/// @solidity memory-safe-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
import "../extensions/draft-IERC20Permit.sol";
import "../../../utils/Address.sol";
/**
* @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 IERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20 {
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));
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IERC20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
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'
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) + value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
function safeDecreaseAllowance(
IERC20 token,
address spender,
uint256 value
) internal {
unchecked {
uint256 oldAllowance = token.allowance(address(this), spender);
require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
uint256 newAllowance = oldAllowance - value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
}
function safePermit(
IERC20Permit token,
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) internal {
uint256 nonceBefore = token.nonces(owner);
token.permit(owner, spender, value, deadline, v, r, s);
uint256 nonceAfter = token.nonces(owner);
require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
}
/**
* @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. We use {Address.functionCall} to perform this call, which verifies that
// the target address contains contract code and also asserts for success in the low-level call.
bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
if (returndata.length > 0) {
// Return data is optional
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
* https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
*
* Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
* presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
* need to send a transaction, and thus is not required to hold Ether at all.
*/
interface IERC20Permit {
/**
* @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
* given ``owner``'s signed approval.
*
* IMPORTANT: The same issues {IERC20-approve} has related to transaction
* ordering also apply here.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `deadline` must be a timestamp in the future.
* - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
* over the EIP712-formatted function arguments.
* - the signature must use ``owner``'s current nonce (see {nonces}).
*
* For more information on the signature format, see the
* https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
* section].
*/
function permit(
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) external;
/**
* @dev Returns the current nonce for `owner`. This value must be
* included whenever a signature is generated for {permit}.
*
* Every successful call to {permit} increases ``owner``'s nonce by one. This
* prevents a signature from being used multiple times.
*/
function nonces(address owner) external view returns (uint256);
/**
* @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
*/
// solhint-disable-next-line func-name-mixedcase
function DOMAIN_SEPARATOR() external view returns (bytes32);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @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 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 `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, 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 `from` to `to` 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 from,
address to,
uint256 amount
) external returns (bool);
}