// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)pragmasolidity ^0.8.1;/**
* @dev Collection of functions related to the address type
*/libraryAddress{
/**
* @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
*
* Furthermore, `isContract` will also return true if the target contract within
* the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
* which only has an effect at the end of a transaction.
* ====
*
* [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.
* ====
*/functionisContract(address account) internalviewreturns (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://consensys.net/diligence/blog/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/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/functionsendValue(addresspayable 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._
*/functionfunctionCall(address target, bytesmemory data) internalreturns (bytesmemory) {
return functionCallWithValue(target, data, 0, "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._
*/functionfunctionCall(address target,
bytesmemory data,
stringmemory errorMessage
) internalreturns (bytesmemory) {
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._
*/functionfunctionCallWithValue(address target, bytesmemory data, uint256 value) internalreturns (bytesmemory) {
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._
*/functionfunctionCallWithValue(address target,
bytesmemory data,
uint256 value,
stringmemory errorMessage
) internalreturns (bytesmemory) {
require(address(this).balance>= value, "Address: insufficient balance for call");
(bool success, bytesmemory returndata) = target.call{value: value}(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/functionfunctionStaticCall(address target, bytesmemory data) internalviewreturns (bytesmemory) {
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._
*/functionfunctionStaticCall(address target,
bytesmemory data,
stringmemory errorMessage
) internalviewreturns (bytesmemory) {
(bool success, bytesmemory returndata) = target.staticcall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/functionfunctionDelegateCall(address target, bytesmemory data) internalreturns (bytesmemory) {
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._
*/functionfunctionDelegateCall(address target,
bytesmemory data,
stringmemory errorMessage
) internalreturns (bytesmemory) {
(bool success, bytesmemory returndata) = target.delegatecall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
* the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
*
* _Available since v4.8._
*/functionverifyCallResultFromTarget(address target,
bool success,
bytesmemory returndata,
stringmemory errorMessage
) internalviewreturns (bytesmemory) {
if (success) {
if (returndata.length==0) {
// only check isContract if the call was successful and the return data is empty// otherwise we already know that it was a contractrequire(isContract(target), "Address: call to non-contract");
}
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
/**
* @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason or using the provided one.
*
* _Available since v4.3._
*/functionverifyCallResult(bool success,
bytesmemory returndata,
stringmemory errorMessage
) internalpurereturns (bytesmemory) {
if (success) {
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
function_revert(bytesmemory returndata, stringmemory errorMessage) privatepure{
// Look for revert reason and bubble it up if presentif (returndata.length>0) {
// The easiest way to bubble the revert reason is using memory via assembly/// @solidity memory-safe-assemblyassembly {
let returndata_size :=mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
// SPDX-License-Identifier: Unlicense/*
* @title Solidity Bytes Arrays Utils
* @author Gonçalo Sá <goncalo.sa@consensys.net>
*
* @dev Bytes tightly packed arrays utility library for ethereum contracts written in Solidity.
* The library lets you concatenate, slice and type cast bytes arrays both in memory and storage.
*/pragmasolidity >=0.8.0 <0.9.0;libraryBytesLib{
functionconcat(bytesmemory _preBytes, bytesmemory _postBytes) internalpurereturns (bytesmemory) {
bytesmemory tempBytes;
assembly {
// Get a location of some free memory and store it in tempBytes as// Solidity does for memory variables.
tempBytes :=mload(0x40)
// Store the length of the first bytes array at the beginning of// the memory for tempBytes.let length :=mload(_preBytes)
mstore(tempBytes, length)
// Maintain a memory counter for the current write location in the// temp bytes array by adding the 32 bytes for the array length to// the starting location.let mc :=add(tempBytes, 0x20)
// Stop copying when the memory counter reaches the length of the// first bytes array.let end :=add(mc, length)
for {
// Initialize a copy counter to the start of the _preBytes data,// 32 bytes into its memory.let cc :=add(_preBytes, 0x20)
} lt(mc, end) {
// Increase both counters by 32 bytes each iteration.
mc :=add(mc, 0x20)
cc :=add(cc, 0x20)
} {
// Write the _preBytes data into the tempBytes memory 32 bytes// at a time.mstore(mc, mload(cc))
}
// Add the length of _postBytes to the current length of tempBytes// and store it as the new length in the first 32 bytes of the// tempBytes memory.
length :=mload(_postBytes)
mstore(tempBytes, add(length, mload(tempBytes)))
// Move the memory counter back from a multiple of 0x20 to the// actual end of the _preBytes data.
mc := end
// Stop copying when the memory counter reaches the new combined// length of the arrays.
end :=add(mc, length)
for {
let cc :=add(_postBytes, 0x20)
} lt(mc, end) {
mc :=add(mc, 0x20)
cc :=add(cc, 0x20)
} {
mstore(mc, mload(cc))
}
// Update the free-memory pointer by padding our last write location// to 32 bytes: add 31 bytes to the end of tempBytes to move to the// next 32 byte block, then round down to the nearest multiple of// 32. If the sum of the length of the two arrays is zero then add// one before rounding down to leave a blank 32 bytes (the length block with 0).mstore(
0x40,
and(
add(add(end, iszero(add(length, mload(_preBytes)))), 31),
not(31) // Round down to the nearest 32 bytes.
)
)
}
return tempBytes;
}
functionconcatStorage(bytesstorage _preBytes, bytesmemory _postBytes) internal{
assembly {
// Read the first 32 bytes of _preBytes storage, which is the length// of the array. (We don't need to use the offset into the slot// because arrays use the entire slot.)let fslot :=sload(_preBytes.slot)
// Arrays of 31 bytes or less have an even value in their slot,// while longer arrays have an odd value. The actual length is// the slot divided by two for odd values, and the lowest order// byte divided by two for even values.// If the slot is even, bitwise and the slot with 255 and divide by// two to get the length. If the slot is odd, bitwise and the slot// with -1 and divide by two.let slength :=div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
let mlength :=mload(_postBytes)
let newlength :=add(slength, mlength)
// slength can contain both the length and contents of the array// if length < 32 bytes so let's prepare for that// v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storageswitchadd(lt(slength, 32), lt(newlength, 32))
case2 {
// Since the new array still fits in the slot, we just need to// update the contents of the slot.// uint256(bytes_storage) = uint256(bytes_storage) + uint256(bytes_memory) + new_lengthsstore(
_preBytes.slot,
// all the modifications to the slot are inside this// next blockadd(
// we can just add to the slot contents because the// bytes we want to change are the LSBs
fslot,
add(
mul(
div(
// load the bytes from memorymload(add(_postBytes, 0x20)),
// zero all bytes to the rightexp(0x100, sub(32, mlength))
),
// and now shift left the number of bytes to// leave space for the length in the slotexp(0x100, sub(32, newlength))
),
// increase length by the double of the memory// bytes lengthmul(mlength, 2)
)
)
)
}
case1 {
// The stored value fits in the slot, but the combined value// will exceed it.// get the keccak hash to get the contents of the arraymstore(0x0, _preBytes.slot)
let sc :=add(keccak256(0x0, 0x20), div(slength, 32))
// save new lengthsstore(_preBytes.slot, add(mul(newlength, 2), 1))
// The contents of the _postBytes array start 32 bytes into// the structure. Our first read should obtain the `submod`// bytes that can fit into the unused space in the last word// of the stored array. To get this, we read 32 bytes starting// from `submod`, so the data we read overlaps with the array// contents by `submod` bytes. Masking the lowest-order// `submod` bytes allows us to add that value directly to the// stored value.let submod :=sub(32, slength)
let mc :=add(_postBytes, submod)
let end :=add(_postBytes, mlength)
let mask :=sub(exp(0x100, submod), 1)
sstore(sc, add(and(fslot, 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff00), and(mload(mc), mask)))
for {
mc :=add(mc, 0x20)
sc :=add(sc, 1)
} lt(mc, end) {
sc :=add(sc, 1)
mc :=add(mc, 0x20)
} {
sstore(sc, mload(mc))
}
mask :=exp(0x100, sub(mc, end))
sstore(sc, mul(div(mload(mc), mask), mask))
}
default {
// get the keccak hash to get the contents of the arraymstore(0x0, _preBytes.slot)
// Start copying to the last used word of the stored array.let sc :=add(keccak256(0x0, 0x20), div(slength, 32))
// save new lengthsstore(_preBytes.slot, add(mul(newlength, 2), 1))
// Copy over the first `submod` bytes of the new data as in// case 1 above.let slengthmod :=mod(slength, 32)
let mlengthmod :=mod(mlength, 32)
let submod :=sub(32, slengthmod)
let mc :=add(_postBytes, submod)
let end :=add(_postBytes, mlength)
let mask :=sub(exp(0x100, submod), 1)
sstore(sc, add(sload(sc), and(mload(mc), mask)))
for {
sc :=add(sc, 1)
mc :=add(mc, 0x20)
} lt(mc, end) {
sc :=add(sc, 1)
mc :=add(mc, 0x20)
} {
sstore(sc, mload(mc))
}
mask :=exp(0x100, sub(mc, end))
sstore(sc, mul(div(mload(mc), mask), mask))
}
}
}
functionslice(bytesmemory _bytes,
uint _start,
uint _length
) internalpurereturns (bytesmemory) {
require(_length +31>= _length, "slice_overflow");
require(_bytes.length>= _start + _length, "slice_outOfBounds");
bytesmemory tempBytes;
assembly {
switchiszero(_length)
case0 {
// Get a location of some free memory and store it in tempBytes as// Solidity does for memory variables.
tempBytes :=mload(0x40)
// The first word of the slice result is potentially a partial// word read from the original array. To read it, we calculate// the length of that partial word and start copying that many// bytes into the array. The first word we copy will start with// data we don't care about, but the last `lengthmod` bytes will// land at the beginning of the contents of the new array. When// we're done copying, we overwrite the full first word with// the actual length of the slice.let lengthmod :=and(_length, 31)
// The multiplication in the next line is necessary// because when slicing multiples of 32 bytes (lengthmod == 0)// the following copy loop was copying the origin's length// and then ending prematurely not copying everything it should.let mc :=add(add(tempBytes, lengthmod), mul(0x20, iszero(lengthmod)))
let end :=add(mc, _length)
for {
// The multiplication in the next line has the same exact purpose// as the one above.let cc :=add(add(add(_bytes, lengthmod), mul(0x20, iszero(lengthmod))), _start)
} lt(mc, end) {
mc :=add(mc, 0x20)
cc :=add(cc, 0x20)
} {
mstore(mc, mload(cc))
}
mstore(tempBytes, _length)
//update free-memory pointer//allocating the array padded to 32 bytes like the compiler does nowmstore(0x40, and(add(mc, 31), not(31)))
}
//if we want a zero-length slice let's just return a zero-length arraydefault {
tempBytes :=mload(0x40)
//zero out the 32 bytes slice we are about to return//we need to do it because Solidity does not garbage collectmstore(tempBytes, 0)
mstore(0x40, add(tempBytes, 0x20))
}
}
return tempBytes;
}
functiontoAddress(bytesmemory _bytes, uint _start) internalpurereturns (address) {
require(_bytes.length>= _start +20, "toAddress_outOfBounds");
address tempAddress;
assembly {
tempAddress :=div(mload(add(add(_bytes, 0x20), _start)), 0x1000000000000000000000000)
}
return tempAddress;
}
functiontoUint8(bytesmemory _bytes, uint _start) internalpurereturns (uint8) {
require(_bytes.length>= _start +1, "toUint8_outOfBounds");
uint8 tempUint;
assembly {
tempUint :=mload(add(add(_bytes, 0x1), _start))
}
return tempUint;
}
functiontoUint16(bytesmemory _bytes, uint _start) internalpurereturns (uint16) {
require(_bytes.length>= _start +2, "toUint16_outOfBounds");
uint16 tempUint;
assembly {
tempUint :=mload(add(add(_bytes, 0x2), _start))
}
return tempUint;
}
functiontoUint32(bytesmemory _bytes, uint _start) internalpurereturns (uint32) {
require(_bytes.length>= _start +4, "toUint32_outOfBounds");
uint32 tempUint;
assembly {
tempUint :=mload(add(add(_bytes, 0x4), _start))
}
return tempUint;
}
functiontoUint64(bytesmemory _bytes, uint _start) internalpurereturns (uint64) {
require(_bytes.length>= _start +8, "toUint64_outOfBounds");
uint64 tempUint;
assembly {
tempUint :=mload(add(add(_bytes, 0x8), _start))
}
return tempUint;
}
functiontoUint96(bytesmemory _bytes, uint _start) internalpurereturns (uint96) {
require(_bytes.length>= _start +12, "toUint96_outOfBounds");
uint96 tempUint;
assembly {
tempUint :=mload(add(add(_bytes, 0xc), _start))
}
return tempUint;
}
functiontoUint128(bytesmemory _bytes, uint _start) internalpurereturns (uint128) {
require(_bytes.length>= _start +16, "toUint128_outOfBounds");
uint128 tempUint;
assembly {
tempUint :=mload(add(add(_bytes, 0x10), _start))
}
return tempUint;
}
functiontoUint256(bytesmemory _bytes, uint _start) internalpurereturns (uint) {
require(_bytes.length>= _start +32, "toUint256_outOfBounds");
uint tempUint;
assembly {
tempUint :=mload(add(add(_bytes, 0x20), _start))
}
return tempUint;
}
functiontoBytes32(bytesmemory _bytes, uint _start) internalpurereturns (bytes32) {
require(_bytes.length>= _start +32, "toBytes32_outOfBounds");
bytes32 tempBytes32;
assembly {
tempBytes32 :=mload(add(add(_bytes, 0x20), _start))
}
return tempBytes32;
}
functionequal(bytesmemory _preBytes, bytesmemory _postBytes) internalpurereturns (bool) {
bool success =true;
assembly {
let length :=mload(_preBytes)
// if lengths don't match the arrays are not equalswitcheq(length, mload(_postBytes))
case1 {
// cb is a circuit breaker in the for loop since there's// no said feature for inline assembly loops// cb = 1 - don't breaker// cb = 0 - breaklet cb :=1let mc :=add(_preBytes, 0x20)
let end :=add(mc, length)
for {
let cc :=add(_postBytes, 0x20)
// the next line is the loop condition:// while(uint256(mc < end) + cb == 2)
} eq(add(lt(mc, end), cb), 2) {
mc :=add(mc, 0x20)
cc :=add(cc, 0x20)
} {
// if any of these checks fails then arrays are not equalifiszero(eq(mload(mc), mload(cc))) {
// unsuccess:
success :=0
cb :=0
}
}
}
default {
// unsuccess:
success :=0
}
}
return success;
}
functionequalStorage(bytesstorage _preBytes, bytesmemory _postBytes) internalviewreturns (bool) {
bool success =true;
assembly {
// we know _preBytes_offset is 0let fslot :=sload(_preBytes.slot)
// Decode the length of the stored array like in concatStorage().let slength :=div(and(fslot, sub(mul(0x100, iszero(and(fslot, 1))), 1)), 2)
let mlength :=mload(_postBytes)
// if lengths don't match the arrays are not equalswitcheq(slength, mlength)
case1 {
// slength can contain both the length and contents of the array// if length < 32 bytes so let's prepare for that// v. http://solidity.readthedocs.io/en/latest/miscellaneous.html#layout-of-state-variables-in-storageifiszero(iszero(slength)) {
switchlt(slength, 32)
case1 {
// blank the last byte which is the length
fslot :=mul(div(fslot, 0x100), 0x100)
ifiszero(eq(fslot, mload(add(_postBytes, 0x20)))) {
// unsuccess:
success :=0
}
}
default {
// cb is a circuit breaker in the for loop since there's// no said feature for inline assembly loops// cb = 1 - don't breaker// cb = 0 - breaklet cb :=1// get the keccak hash to get the contents of the arraymstore(0x0, _preBytes.slot)
let sc :=keccak256(0x0, 0x20)
let mc :=add(_postBytes, 0x20)
let end :=add(mc, mlength)
// the next line is the loop condition:// while(uint256(mc < end) + cb == 2)for {
} eq(add(lt(mc, end), cb), 2) {
sc :=add(sc, 1)
mc :=add(mc, 0x20)
} {
ifiszero(eq(sload(sc), mload(mc))) {
// unsuccess:
success :=0
cb :=0
}
}
}
}
}
default {
// unsuccess:
success :=0
}
}
return success;
}
}
Contract Source Code
File 4 of 22: Context.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.9.4) (utils/Context.sol)pragmasolidity ^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.
*/abstractcontractContext{
function_msgSender() internalviewvirtualreturns (address) {
returnmsg.sender;
}
function_msgData() internalviewvirtualreturns (bytescalldata) {
returnmsg.data;
}
function_contextSuffixLength() internalviewvirtualreturns (uint256) {
return0;
}
}
Contract Source Code
File 5 of 22: ERC165.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)pragmasolidity ^0.8.0;import"./IERC165.sol";
/**
* @dev Implementation of the {IERC165} interface.
*
* Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
* for the additional interface id that will be supported. For example:
*
* ```solidity
* function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
* return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
* }
* ```
*
* Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
*/abstractcontractERC165isIERC165{
/**
* @dev See {IERC165-supportsInterface}.
*/functionsupportsInterface(bytes4 interfaceId) publicviewvirtualoverridereturns (bool) {
return interfaceId ==type(IERC165).interfaceId;
}
}
Contract Source Code
File 6 of 22: ExcessivelySafeCall.sol
// SPDX-License-Identifier: MIT OR Apache-2.0pragmasolidity >=0.7.6;libraryExcessivelySafeCall{
uintconstant LOW_28_MASK =0x00000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffff;
/// @notice Use when you _really_ really _really_ don't trust the called/// contract. This prevents the called contract from causing reversion of/// the caller in as many ways as we can./// @dev The main difference between this and a solidity low-level call is/// that we limit the number of bytes that the callee can cause to be/// copied to caller memory. This prevents stupid things like malicious/// contracts returning 10,000,000 bytes causing a local OOG when copying/// to memory./// @param _target The address to call/// @param _gas The amount of gas to forward to the remote contract/// @param _maxCopy The maximum number of bytes of returndata to copy/// to memory./// @param _calldata The data to send to the remote contract/// @return success and returndata, as `.call()`. Returndata is capped to/// `_maxCopy` bytes.functionexcessivelySafeCall(address _target,
uint _gas,
uint16 _maxCopy,
bytesmemory _calldata
) internalreturns (bool, bytesmemory) {
// set up for assembly calluint _toCopy;
bool _success;
bytesmemory _returnData =newbytes(_maxCopy);
// dispatch message to recipient// by assembly calling "handle" function// we call via assembly to avoid memcopying a very large returndata// returned by a malicious contractassembly {
_success :=call(
_gas, // gas
_target, // recipient0, // ether valueadd(_calldata, 0x20), // inlocmload(_calldata), // inlen0, // outloc0// outlen
)
// limit our copy to 256 bytes
_toCopy :=returndatasize()
ifgt(_toCopy, _maxCopy) {
_toCopy := _maxCopy
}
// Store the length of the copied bytesmstore(_returnData, _toCopy)
// copy the bytes from returndata[0:_toCopy]returndatacopy(add(_returnData, 0x20), 0, _toCopy)
}
return (_success, _returnData);
}
/// @notice Use when you _really_ really _really_ don't trust the called/// contract. This prevents the called contract from causing reversion of/// the caller in as many ways as we can./// @dev The main difference between this and a solidity low-level call is/// that we limit the number of bytes that the callee can cause to be/// copied to caller memory. This prevents stupid things like malicious/// contracts returning 10,000,000 bytes causing a local OOG when copying/// to memory./// @param _target The address to call/// @param _gas The amount of gas to forward to the remote contract/// @param _maxCopy The maximum number of bytes of returndata to copy/// to memory./// @param _calldata The data to send to the remote contract/// @return success and returndata, as `.call()`. Returndata is capped to/// `_maxCopy` bytes.functionexcessivelySafeStaticCall(address _target,
uint _gas,
uint16 _maxCopy,
bytesmemory _calldata
) internalviewreturns (bool, bytesmemory) {
// set up for assembly calluint _toCopy;
bool _success;
bytesmemory _returnData =newbytes(_maxCopy);
// dispatch message to recipient// by assembly calling "handle" function// we call via assembly to avoid memcopying a very large returndata// returned by a malicious contractassembly {
_success :=staticcall(
_gas, // gas
_target, // recipientadd(_calldata, 0x20), // inlocmload(_calldata), // inlen0, // outloc0// outlen
)
// limit our copy to 256 bytes
_toCopy :=returndatasize()
ifgt(_toCopy, _maxCopy) {
_toCopy := _maxCopy
}
// Store the length of the copied bytesmstore(_returnData, _toCopy)
// copy the bytes from returndata[0:_toCopy]returndatacopy(add(_returnData, 0x20), 0, _toCopy)
}
return (_success, _returnData);
}
/**
* @notice Swaps function selectors in encoded contract calls
* @dev Allows reuse of encoded calldata for functions with identical
* argument types but different names. It simply swaps out the first 4 bytes
* for the new selector. This function modifies memory in place, and should
* only be used with caution.
* @param _newSelector The new 4-byte selector
* @param _buf The encoded contract args
*/functionswapSelector(bytes4 _newSelector, bytesmemory _buf) internalpure{
require(_buf.length>=4);
uint _mask = LOW_28_MASK;
assembly {
// load the first word oflet _word :=mload(add(_buf, 0x20))
// mask out the top 4 bytes// /x
_word :=and(_word, _mask)
_word :=or(_newSelector, _word)
mstore(add(_buf, 0x20), _word)
}
}
}
Contract Source Code
File 7 of 22: ICommonOFT.sol
// SPDX-License-Identifier: MITpragmasolidity >=0.5.0;import"@openzeppelin/contracts/utils/introspection/IERC165.sol";
/**
* @dev Interface of the IOFT core standard
*/interfaceICommonOFTisIERC165{
structLzCallParams {
addresspayable refundAddress;
address zroPaymentAddress;
bytes adapterParams;
}
/**
* @dev estimate send token `_tokenId` to (`_dstChainId`, `_toAddress`)
* _dstChainId - L0 defined chain id to send tokens too
* _toAddress - dynamic bytes array which contains the address to whom you are sending tokens to on the dstChain
* _amount - amount of the tokens to transfer
* _useZro - indicates to use zro to pay L0 fees
* _adapterParam - flexible bytes array to indicate messaging adapter services in L0
*/functionestimateSendFee(uint16 _dstChainId, bytes32 _toAddress, uint _amount, bool _useZro, bytescalldata _adapterParams) externalviewreturns (uint nativeFee, uint zroFee);
functionestimateSendAndCallFee(uint16 _dstChainId, bytes32 _toAddress, uint _amount, bytescalldata _payload, uint64 _dstGasForCall, bool _useZro, bytescalldata _adapterParams) externalviewreturns (uint nativeFee, uint zroFee);
/**
* @dev returns the circulating amount of tokens on current chain
*/functioncirculatingSupply() externalviewreturns (uint);
/**
* @dev returns the address of the ERC20 token
*/functiontoken() externalviewreturns (address);
}
Contract Source Code
File 8 of 22: IERC165.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)pragmasolidity ^0.8.0;/**
* @dev Interface of the ERC165 standard, as defined in the
* https://eips.ethereum.org/EIPS/eip-165[EIP].
*
* Implementers can declare support of contract interfaces, which can then be
* queried by others ({ERC165Checker}).
*
* For an implementation, see {ERC165}.
*/interfaceIERC165{
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
* to learn more about how these ids are created.
*
* This function call must use less than 30 000 gas.
*/functionsupportsInterface(bytes4 interfaceId) externalviewreturns (bool);
}
Contract Source Code
File 9 of 22: IERC20.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)pragmasolidity ^0.8.0;/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/interfaceIERC20{
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/eventTransfer(addressindexedfrom, addressindexed 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.
*/eventApproval(addressindexed owner, addressindexed spender, uint256 value);
/**
* @dev Returns the amount of tokens in existence.
*/functiontotalSupply() externalviewreturns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/functionbalanceOf(address account) externalviewreturns (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.
*/functiontransfer(address to, uint256 amount) externalreturns (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.
*/functionallowance(address owner, address spender) externalviewreturns (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.
*/functionapprove(address spender, uint256 amount) externalreturns (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.
*/functiontransferFrom(addressfrom, address to, uint256 amount) externalreturns (bool);
}
Contract Source Code
File 10 of 22: IERC20Permit.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.9.4) (token/ERC20/extensions/IERC20Permit.sol)pragmasolidity ^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.
*
* ==== Security Considerations
*
* There are two important considerations concerning the use of `permit`. The first is that a valid permit signature
* expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be
* considered as an intention to spend the allowance in any specific way. The second is that because permits have
* built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should
* take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be
* generally recommended is:
*
* ```solidity
* function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public {
* try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {}
* doThing(..., value);
* }
*
* function doThing(..., uint256 value) public {
* token.safeTransferFrom(msg.sender, address(this), value);
* ...
* }
* ```
*
* Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of
* `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also
* {SafeERC20-safeTransferFrom}).
*
* Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so
* contracts should have entry points that don't rely on permit.
*/interfaceIERC20Permit{
/**
* @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].
*
* CAUTION: See Security Considerations above.
*/functionpermit(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.
*/functionnonces(address owner) externalviewreturns (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-mixedcasefunctionDOMAIN_SEPARATOR() externalviewreturns (bytes32);
}
Contract Source Code
File 11 of 22: ILayerZeroEndpoint.sol
// SPDX-License-Identifier: MITpragmasolidity >=0.5.0;import"./ILayerZeroUserApplicationConfig.sol";
interfaceILayerZeroEndpointisILayerZeroUserApplicationConfig{
// @notice send a LayerZero message to the specified address at a LayerZero endpoint.// @param _dstChainId - the destination chain identifier// @param _destination - the address on destination chain (in bytes). address length/format may vary by chains// @param _payload - a custom bytes payload to send to the destination contract// @param _refundAddress - if the source transaction is cheaper than the amount of value passed, refund the additional amount to this address// @param _zroPaymentAddress - the address of the ZRO token holder who would pay for the transaction// @param _adapterParams - parameters for custom functionality. e.g. receive airdropped native gas from the relayer on destinationfunctionsend(uint16 _dstChainId,
bytescalldata _destination,
bytescalldata _payload,
addresspayable _refundAddress,
address _zroPaymentAddress,
bytescalldata _adapterParams
) externalpayable;
// @notice used by the messaging library to publish verified payload// @param _srcChainId - the source chain identifier// @param _srcAddress - the source contract (as bytes) at the source chain// @param _dstAddress - the address on destination chain// @param _nonce - the unbound message ordering nonce// @param _gasLimit - the gas limit for external contract execution// @param _payload - verified payload to send to the destination contractfunctionreceivePayload(uint16 _srcChainId,
bytescalldata _srcAddress,
address _dstAddress,
uint64 _nonce,
uint _gasLimit,
bytescalldata _payload
) external;
// @notice get the inboundNonce of a lzApp from a source chain which could be EVM or non-EVM chain// @param _srcChainId - the source chain identifier// @param _srcAddress - the source chain contract addressfunctiongetInboundNonce(uint16 _srcChainId, bytescalldata _srcAddress) externalviewreturns (uint64);
// @notice get the outboundNonce from this source chain which, consequently, is always an EVM// @param _srcAddress - the source chain contract addressfunctiongetOutboundNonce(uint16 _dstChainId, address _srcAddress) externalviewreturns (uint64);
// @notice gets a quote in source native gas, for the amount that send() requires to pay for message delivery// @param _dstChainId - the destination chain identifier// @param _userApplication - the user app address on this EVM chain// @param _payload - the custom message to send over LayerZero// @param _payInZRO - if false, user app pays the protocol fee in native token// @param _adapterParam - parameters for the adapter service, e.g. send some dust native token to dstChainfunctionestimateFees(uint16 _dstChainId,
address _userApplication,
bytescalldata _payload,
bool _payInZRO,
bytescalldata _adapterParam
) externalviewreturns (uint nativeFee, uint zroFee);
// @notice get this Endpoint's immutable source identifierfunctiongetChainId() externalviewreturns (uint16);
// @notice the interface to retry failed message on this Endpoint destination// @param _srcChainId - the source chain identifier// @param _srcAddress - the source chain contract address// @param _payload - the payload to be retriedfunctionretryPayload(uint16 _srcChainId,
bytescalldata _srcAddress,
bytescalldata _payload
) external;
// @notice query if any STORED payload (message blocking) at the endpoint.// @param _srcChainId - the source chain identifier// @param _srcAddress - the source chain contract addressfunctionhasStoredPayload(uint16 _srcChainId, bytescalldata _srcAddress) externalviewreturns (bool);
// @notice query if the _libraryAddress is valid for sending msgs.// @param _userApplication - the user app address on this EVM chainfunctiongetSendLibraryAddress(address _userApplication) externalviewreturns (address);
// @notice query if the _libraryAddress is valid for receiving msgs.// @param _userApplication - the user app address on this EVM chainfunctiongetReceiveLibraryAddress(address _userApplication) externalviewreturns (address);
// @notice query if the non-reentrancy guard for send() is on// @return true if the guard is on. false otherwisefunctionisSendingPayload() externalviewreturns (bool);
// @notice query if the non-reentrancy guard for receive() is on// @return true if the guard is on. false otherwisefunctionisReceivingPayload() externalviewreturns (bool);
// @notice get the configuration of the LayerZero messaging library of the specified version// @param _version - messaging library version// @param _chainId - the chainId for the pending config change// @param _userApplication - the contract address of the user application// @param _configType - type of configuration. every messaging library has its own convention.functiongetConfig(uint16 _version,
uint16 _chainId,
address _userApplication,
uint _configType
) externalviewreturns (bytesmemory);
// @notice get the send() LayerZero messaging library version// @param _userApplication - the contract address of the user applicationfunctiongetSendVersion(address _userApplication) externalviewreturns (uint16);
// @notice get the lzReceive() LayerZero messaging library version// @param _userApplication - the contract address of the user applicationfunctiongetReceiveVersion(address _userApplication) externalviewreturns (uint16);
}
Contract Source Code
File 12 of 22: ILayerZeroReceiver.sol
// SPDX-License-Identifier: MITpragmasolidity >=0.5.0;interfaceILayerZeroReceiver{
// @notice LayerZero endpoint will invoke this function to deliver the message on the destination// @param _srcChainId - the source endpoint identifier// @param _srcAddress - the source sending contract address from the source chain// @param _nonce - the ordered message nonce// @param _payload - the signed payload is the UA bytes has encoded to be sentfunctionlzReceive(uint16 _srcChainId,
bytescalldata _srcAddress,
uint64 _nonce,
bytescalldata _payload
) external;
}
Contract Source Code
File 13 of 22: ILayerZeroUserApplicationConfig.sol
// SPDX-License-Identifier: MITpragmasolidity >=0.5.0;interfaceILayerZeroUserApplicationConfig{
// @notice set the configuration of the LayerZero messaging library of the specified version// @param _version - messaging library version// @param _chainId - the chainId for the pending config change// @param _configType - type of configuration. every messaging library has its own convention.// @param _config - configuration in the bytes. can encode arbitrary content.functionsetConfig(uint16 _version,
uint16 _chainId,
uint _configType,
bytescalldata _config
) external;
// @notice set the send() LayerZero messaging library version to _version// @param _version - new messaging library versionfunctionsetSendVersion(uint16 _version) external;
// @notice set the lzReceive() LayerZero messaging library version to _version// @param _version - new messaging library versionfunctionsetReceiveVersion(uint16 _version) external;
// @notice Only when the UA needs to resume the message flow in blocking mode and clear the stored payload// @param _srcChainId - the chainId of the source chain// @param _srcAddress - the contract address of the source contract at the source chainfunctionforceResumeReceive(uint16 _srcChainId, bytescalldata _srcAddress) external;
}
Contract Source Code
File 14 of 22: IOFTReceiverV2.sol
// SPDX-License-Identifier: BUSL-1.1pragmasolidity >=0.5.0;interfaceIOFTReceiverV2{
/**
* @dev Called by the OFT contract when tokens are received from source chain.
* @param _srcChainId The chain id of the source chain.
* @param _srcAddress The address of the OFT token contract on the source chain.
* @param _nonce The nonce of the transaction on the source chain.
* @param _from The address of the account who calls the sendAndCall() on the source chain.
* @param _amount The amount of tokens to transfer.
* @param _payload Additional data with no specified format.
*/functiononOFTReceived(uint16 _srcChainId, bytescalldata _srcAddress, uint64 _nonce, bytes32 _from, uint _amount, bytescalldata _payload) external;
}
Contract Source Code
File 15 of 22: IOFTV2.sol
// SPDX-License-Identifier: MITpragmasolidity >=0.5.0;import"./ICommonOFT.sol";
/**
* @dev Interface of the IOFT core standard
*/interfaceIOFTV2isICommonOFT{
/**
* @dev send `_amount` amount of token to (`_dstChainId`, `_toAddress`) from `_from`
* `_from` the owner of token
* `_dstChainId` the destination chain identifier
* `_toAddress` can be any size depending on the `dstChainId`.
* `_amount` the quantity of tokens in wei
* `_refundAddress` the address LayerZero refunds if too much message fee is sent
* `_zroPaymentAddress` set to address(0x0) if not paying in ZRO (LayerZero Token)
* `_adapterParams` is a flexible bytes array to indicate messaging adapter services
*/functionsendFrom(address _from, uint16 _dstChainId, bytes32 _toAddress, uint _amount, LzCallParams calldata _callParams) externalpayable;
functionsendAndCall(address _from, uint16 _dstChainId, bytes32 _toAddress, uint _amount, bytescalldata _payload, uint64 _dstGasForCall, LzCallParams calldata _callParams) externalpayable;
}
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;import"@openzeppelin/contracts/access/Ownable.sol";
import"./interfaces/ILayerZeroReceiver.sol";
import"./interfaces/ILayerZeroUserApplicationConfig.sol";
import"./interfaces/ILayerZeroEndpoint.sol";
import"../libraries/BytesLib.sol";
/*
* a generic LzReceiver implementation
*/abstractcontractLzAppisOwnable, ILayerZeroReceiver, ILayerZeroUserApplicationConfig{
usingBytesLibforbytes;
// ua can not send payload larger than this by default, but it can be changed by the ua owneruintpublicconstant DEFAULT_PAYLOAD_SIZE_LIMIT =10000;
ILayerZeroEndpoint publicimmutable lzEndpoint;
mapping(uint16=>bytes) public trustedRemoteLookup;
mapping(uint16=>mapping(uint16=>uint)) public minDstGasLookup;
mapping(uint16=>uint) public payloadSizeLimitLookup;
addresspublic precrime;
eventSetPrecrime(address precrime);
eventSetTrustedRemote(uint16 _remoteChainId, bytes _path);
eventSetTrustedRemoteAddress(uint16 _remoteChainId, bytes _remoteAddress);
eventSetMinDstGas(uint16 _dstChainId, uint16 _type, uint _minDstGas);
constructor(address _endpoint) {
lzEndpoint = ILayerZeroEndpoint(_endpoint);
}
functionlzReceive(uint16 _srcChainId,
bytescalldata _srcAddress,
uint64 _nonce,
bytescalldata _payload
) publicvirtualoverride{
// lzReceive must be called by the endpoint for securityrequire(_msgSender() ==address(lzEndpoint), "LzApp: invalid endpoint caller");
bytesmemory trustedRemote = trustedRemoteLookup[_srcChainId];
// if will still block the message pathway from (srcChainId, srcAddress). should not receive message from untrusted remote.require(
_srcAddress.length== trustedRemote.length&& trustedRemote.length>0&&keccak256(_srcAddress) ==keccak256(trustedRemote),
"LzApp: invalid source sending contract"
);
_blockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
}
// abstract function - the default behaviour of LayerZero is blocking. See: NonblockingLzApp if you dont need to enforce ordered messagingfunction_blockingLzReceive(uint16 _srcChainId,
bytesmemory _srcAddress,
uint64 _nonce,
bytesmemory _payload
) internalvirtual;
function_lzSend(uint16 _dstChainId,
bytesmemory _payload,
addresspayable _refundAddress,
address _zroPaymentAddress,
bytesmemory _adapterParams,
uint _nativeFee
) internalvirtual{
bytesmemory trustedRemote = trustedRemoteLookup[_dstChainId];
require(trustedRemote.length!=0, "LzApp: destination chain is not a trusted source");
_checkPayloadSize(_dstChainId, _payload.length);
lzEndpoint.send{value: _nativeFee}(_dstChainId, trustedRemote, _payload, _refundAddress, _zroPaymentAddress, _adapterParams);
}
function_checkGasLimit(uint16 _dstChainId,
uint16 _type,
bytesmemory _adapterParams,
uint _extraGas
) internalviewvirtual{
uint providedGasLimit = _getGasLimit(_adapterParams);
uint minGasLimit = minDstGasLookup[_dstChainId][_type];
require(minGasLimit >0, "LzApp: minGasLimit not set");
require(providedGasLimit >= minGasLimit + _extraGas, "LzApp: gas limit is too low");
}
function_getGasLimit(bytesmemory _adapterParams) internalpurevirtualreturns (uint gasLimit) {
require(_adapterParams.length>=34, "LzApp: invalid adapterParams");
assembly {
gasLimit :=mload(add(_adapterParams, 34))
}
}
function_checkPayloadSize(uint16 _dstChainId, uint _payloadSize) internalviewvirtual{
uint payloadSizeLimit = payloadSizeLimitLookup[_dstChainId];
if (payloadSizeLimit ==0) {
// use default if not set
payloadSizeLimit = DEFAULT_PAYLOAD_SIZE_LIMIT;
}
require(_payloadSize <= payloadSizeLimit, "LzApp: payload size is too large");
}
//---------------------------UserApplication config----------------------------------------functiongetConfig(uint16 _version,
uint16 _chainId,
address,
uint _configType
) externalviewreturns (bytesmemory) {
return lzEndpoint.getConfig(_version, _chainId, address(this), _configType);
}
// generic config for LayerZero user ApplicationfunctionsetConfig(uint16 _version,
uint16 _chainId,
uint _configType,
bytescalldata _config
) externaloverrideonlyOwner{
lzEndpoint.setConfig(_version, _chainId, _configType, _config);
}
functionsetSendVersion(uint16 _version) externaloverrideonlyOwner{
lzEndpoint.setSendVersion(_version);
}
functionsetReceiveVersion(uint16 _version) externaloverrideonlyOwner{
lzEndpoint.setReceiveVersion(_version);
}
functionforceResumeReceive(uint16 _srcChainId, bytescalldata _srcAddress) externaloverrideonlyOwner{
lzEndpoint.forceResumeReceive(_srcChainId, _srcAddress);
}
// _path = abi.encodePacked(remoteAddress, localAddress)// this function set the trusted path for the cross-chain communicationfunctionsetTrustedRemote(uint16 _remoteChainId, bytescalldata _path) externalonlyOwner{
trustedRemoteLookup[_remoteChainId] = _path;
emit SetTrustedRemote(_remoteChainId, _path);
}
functionsetTrustedRemoteAddress(uint16 _remoteChainId, bytescalldata _remoteAddress) externalonlyOwner{
trustedRemoteLookup[_remoteChainId] =abi.encodePacked(_remoteAddress, address(this));
emit SetTrustedRemoteAddress(_remoteChainId, _remoteAddress);
}
functiongetTrustedRemoteAddress(uint16 _remoteChainId) externalviewreturns (bytesmemory) {
bytesmemory path = trustedRemoteLookup[_remoteChainId];
require(path.length!=0, "LzApp: no trusted path record");
return path.slice(0, path.length-20); // the last 20 bytes should be address(this)
}
functionsetPrecrime(address _precrime) externalonlyOwner{
precrime = _precrime;
emit SetPrecrime(_precrime);
}
functionsetMinDstGas(uint16 _dstChainId,
uint16 _packetType,
uint _minGas
) externalonlyOwner{
minDstGasLookup[_dstChainId][_packetType] = _minGas;
emit SetMinDstGas(_dstChainId, _packetType, _minGas);
}
// if the size is 0, it means default size limitfunctionsetPayloadSizeLimit(uint16 _dstChainId, uint _size) externalonlyOwner{
payloadSizeLimitLookup[_dstChainId] = _size;
}
//--------------------------- VIEW FUNCTION ----------------------------------------functionisTrustedRemote(uint16 _srcChainId, bytescalldata _srcAddress) externalviewreturns (bool) {
bytesmemory trustedSource = trustedRemoteLookup[_srcChainId];
returnkeccak256(trustedSource) ==keccak256(_srcAddress);
}
}
Contract Source Code
File 18 of 22: NonblockingLzApp.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;import"./LzApp.sol";
import"../libraries/ExcessivelySafeCall.sol";
/*
* the default LayerZero messaging behaviour is blocking, i.e. any failed message will block the channel
* this abstract class try-catch all fail messages and store locally for future retry. hence, non-blocking
* NOTE: if the srcAddress is not configured properly, it will still block the message pathway from (srcChainId, srcAddress)
*/abstractcontractNonblockingLzAppisLzApp{
usingExcessivelySafeCallforaddress;
constructor(address _endpoint) LzApp(_endpoint) {}
mapping(uint16=>mapping(bytes=>mapping(uint64=>bytes32))) public failedMessages;
eventMessageFailed(uint16 _srcChainId, bytes _srcAddress, uint64 _nonce, bytes _payload, bytes _reason);
eventRetryMessageSuccess(uint16 _srcChainId, bytes _srcAddress, uint64 _nonce, bytes32 _payloadHash);
// overriding the virtual function in LzReceiverfunction_blockingLzReceive(uint16 _srcChainId,
bytesmemory _srcAddress,
uint64 _nonce,
bytesmemory _payload
) internalvirtualoverride{
(bool success, bytesmemory reason) =address(this).excessivelySafeCall(
gasleft(),
150,
abi.encodeWithSelector(this.nonblockingLzReceive.selector, _srcChainId, _srcAddress, _nonce, _payload)
);
if (!success) {
_storeFailedMessage(_srcChainId, _srcAddress, _nonce, _payload, reason);
}
}
function_storeFailedMessage(uint16 _srcChainId,
bytesmemory _srcAddress,
uint64 _nonce,
bytesmemory _payload,
bytesmemory _reason
) internalvirtual{
failedMessages[_srcChainId][_srcAddress][_nonce] =keccak256(_payload);
emit MessageFailed(_srcChainId, _srcAddress, _nonce, _payload, _reason);
}
functionnonblockingLzReceive(uint16 _srcChainId,
bytescalldata _srcAddress,
uint64 _nonce,
bytescalldata _payload
) publicvirtual{
// only internal transactionrequire(_msgSender() ==address(this), "NonblockingLzApp: caller must be LzApp");
_nonblockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
}
//@notice override this functionfunction_nonblockingLzReceive(uint16 _srcChainId,
bytesmemory _srcAddress,
uint64 _nonce,
bytesmemory _payload
) internalvirtual;
functionretryMessage(uint16 _srcChainId,
bytescalldata _srcAddress,
uint64 _nonce,
bytescalldata _payload
) publicpayablevirtual{
// assert there is message to retrybytes32 payloadHash = failedMessages[_srcChainId][_srcAddress][_nonce];
require(payloadHash !=bytes32(0), "NonblockingLzApp: no stored message");
require(keccak256(_payload) == payloadHash, "NonblockingLzApp: invalid payload");
// clear the stored message
failedMessages[_srcChainId][_srcAddress][_nonce] =bytes32(0);
// execute the message. revert if it fails again
_nonblockingLzReceive(_srcChainId, _srcAddress, _nonce, _payload);
emit RetryMessageSuccess(_srcChainId, _srcAddress, _nonce, payloadHash);
}
}
Contract Source Code
File 19 of 22: OFTCoreV2.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;import"../../../lzApp/NonblockingLzApp.sol";
import"../../../libraries/ExcessivelySafeCall.sol";
import"./interfaces/ICommonOFT.sol";
import"./interfaces/IOFTReceiverV2.sol";
abstractcontractOFTCoreV2isNonblockingLzApp{
usingBytesLibforbytes;
usingExcessivelySafeCallforaddress;
uintpublicconstant NO_EXTRA_GAS =0;
// packet typeuint8publicconstant PT_SEND =0;
uint8publicconstant PT_SEND_AND_CALL =1;
uint8publicimmutable sharedDecimals;
mapping(uint16=>mapping(bytes=>mapping(uint64=>bool))) public creditedPackets;
/**
* @dev Emitted when `_amount` tokens are moved from the `_sender` to (`_dstChainId`, `_toAddress`)
* `_nonce` is the outbound nonce
*/eventSendToChain(uint16indexed _dstChainId, addressindexed _from, bytes32indexed _toAddress, uint _amount);
/**
* @dev Emitted when `_amount` tokens are received from `_srcChainId` into the `_toAddress` on the local chain.
* `_nonce` is the inbound nonce.
*/eventReceiveFromChain(uint16indexed _srcChainId, addressindexed _to, uint _amount);
eventCallOFTReceivedSuccess(uint16indexed _srcChainId, bytes _srcAddress, uint64 _nonce, bytes32 _hash);
eventNonContractAddress(address _address);
// _sharedDecimals should be the minimum decimals on all chainsconstructor(uint8 _sharedDecimals, address _lzEndpoint) NonblockingLzApp(_lzEndpoint) {
sharedDecimals = _sharedDecimals;
}
/************************************************************************
* public functions
************************************************************************/functioncallOnOFTReceived(uint16 _srcChainId,
bytescalldata _srcAddress,
uint64 _nonce,
bytes32 _from,
address _to,
uint _amount,
bytescalldata _payload,
uint _gasForCall
) publicvirtual{
require(_msgSender() ==address(this), "OFTCore: caller must be OFTCore");
// send
_amount = _transferFrom(address(this), _to, _amount);
emit ReceiveFromChain(_srcChainId, _to, _amount);
// call
IOFTReceiverV2(_to).onOFTReceived{gas: _gasForCall}(_srcChainId, _srcAddress, _nonce, _from, _amount, _payload);
}
/************************************************************************
* internal functions
************************************************************************/function_estimateSendFee(uint16 _dstChainId,
bytes32 _toAddress,
uint _amount,
bool _useZro,
bytesmemory _adapterParams
) internalviewvirtualreturns (uint nativeFee, uint zroFee) {
// mock the payload for sendFrom()bytesmemory payload = _encodeSendPayload(_toAddress, _ld2sd(_amount));
return lzEndpoint.estimateFees(_dstChainId, address(this), payload, _useZro, _adapterParams);
}
function_estimateSendAndCallFee(uint16 _dstChainId,
bytes32 _toAddress,
uint _amount,
bytesmemory _payload,
uint64 _dstGasForCall,
bool _useZro,
bytesmemory _adapterParams
) internalviewvirtualreturns (uint nativeFee, uint zroFee) {
// mock the payload for sendAndCall()bytesmemory payload = _encodeSendAndCallPayload(msg.sender, _toAddress, _ld2sd(_amount), _payload, _dstGasForCall);
return lzEndpoint.estimateFees(_dstChainId, address(this), payload, _useZro, _adapterParams);
}
function_nonblockingLzReceive(uint16 _srcChainId,
bytesmemory _srcAddress,
uint64 _nonce,
bytesmemory _payload
) internalvirtualoverride{
uint8 packetType = _payload.toUint8(0);
if (packetType == PT_SEND) {
_sendAck(_srcChainId, _srcAddress, _nonce, _payload);
} elseif (packetType == PT_SEND_AND_CALL) {
_sendAndCallAck(_srcChainId, _srcAddress, _nonce, _payload);
} else {
revert("OFTCore: unknown packet type");
}
}
function_send(address _from,
uint16 _dstChainId,
bytes32 _toAddress,
uint _amount,
addresspayable _refundAddress,
address _zroPaymentAddress,
bytesmemory _adapterParams
) internalvirtualreturns (uint amount) {
_checkGasLimit(_dstChainId, PT_SEND, _adapterParams, NO_EXTRA_GAS);
(amount, ) = _removeDust(_amount);
amount = _debitFrom(_from, _dstChainId, _toAddress, amount); // amount returned should not have dustrequire(amount >0, "OFTCore: amount too small");
bytesmemory lzPayload = _encodeSendPayload(_toAddress, _ld2sd(amount));
_lzSend(_dstChainId, lzPayload, _refundAddress, _zroPaymentAddress, _adapterParams, msg.value);
emit SendToChain(_dstChainId, _from, _toAddress, amount);
}
function_sendAck(uint16 _srcChainId,
bytesmemory,
uint64,
bytesmemory _payload
) internalvirtual{
(address to, uint64 amountSD) = _decodeSendPayload(_payload);
if (to ==address(0)) {
to =address(0xdead);
}
uint amount = _sd2ld(amountSD);
amount = _creditTo(_srcChainId, to, amount);
emit ReceiveFromChain(_srcChainId, to, amount);
}
function_sendAndCall(address _from,
uint16 _dstChainId,
bytes32 _toAddress,
uint _amount,
bytesmemory _payload,
uint64 _dstGasForCall,
addresspayable _refundAddress,
address _zroPaymentAddress,
bytesmemory _adapterParams
) internalvirtualreturns (uint amount) {
_checkGasLimit(_dstChainId, PT_SEND_AND_CALL, _adapterParams, _dstGasForCall);
(amount, ) = _removeDust(_amount);
amount = _debitFrom(_from, _dstChainId, _toAddress, amount);
require(amount >0, "OFTCore: amount too small");
// encode the msg.sender into the payload instead of _frombytesmemory lzPayload = _encodeSendAndCallPayload(msg.sender, _toAddress, _ld2sd(amount), _payload, _dstGasForCall);
_lzSend(_dstChainId, lzPayload, _refundAddress, _zroPaymentAddress, _adapterParams, msg.value);
emit SendToChain(_dstChainId, _from, _toAddress, amount);
}
function_sendAndCallAck(uint16 _srcChainId,
bytesmemory _srcAddress,
uint64 _nonce,
bytesmemory _payload
) internalvirtual{
(bytes32from, address to, uint64 amountSD, bytesmemory payloadForCall, uint64 gasForCall) = _decodeSendAndCallPayload(_payload);
bool credited = creditedPackets[_srcChainId][_srcAddress][_nonce];
uint amount = _sd2ld(amountSD);
// credit to this contract first, and then transfer to receiver only if callOnOFTReceived() succeedsif (!credited) {
amount = _creditTo(_srcChainId, address(this), amount);
creditedPackets[_srcChainId][_srcAddress][_nonce] =true;
}
if (!_isContract(to)) {
emit NonContractAddress(to);
return;
}
// workaround for stack too deepuint16 srcChainId = _srcChainId;
bytesmemory srcAddress = _srcAddress;
uint64 nonce = _nonce;
bytesmemory payload = _payload;
bytes32 from_ =from;
address to_ = to;
uint amount_ = amount;
bytesmemory payloadForCall_ = payloadForCall;
// no gas limit for the call if retryuint gas = credited ? gasleft() : gasForCall;
(bool success, bytesmemory reason) =address(this).excessivelySafeCall(
gasleft(),
150,
abi.encodeWithSelector(this.callOnOFTReceived.selector, srcChainId, srcAddress, nonce, from_, to_, amount_, payloadForCall_, gas)
);
if (success) {
bytes32 hash =keccak256(payload);
emit CallOFTReceivedSuccess(srcChainId, srcAddress, nonce, hash);
} else {
// store the failed message into the nonblockingLzApp
_storeFailedMessage(srcChainId, srcAddress, nonce, payload, reason);
}
}
function_isContract(address _account) internalviewreturns (bool) {
return _account.code.length>0;
}
function_ld2sd(uint _amount) internalviewvirtualreturns (uint64) {
uint amountSD = _amount / _ld2sdRate();
require(amountSD <=type(uint64).max, "OFTCore: amountSD overflow");
returnuint64(amountSD);
}
function_sd2ld(uint64 _amountSD) internalviewvirtualreturns (uint) {
return _amountSD * _ld2sdRate();
}
function_removeDust(uint _amount) internalviewvirtualreturns (uint amountAfter, uint dust) {
dust = _amount % _ld2sdRate();
amountAfter = _amount - dust;
}
function_encodeSendPayload(bytes32 _toAddress, uint64 _amountSD) internalviewvirtualreturns (bytesmemory) {
returnabi.encodePacked(PT_SEND, _toAddress, _amountSD);
}
function_decodeSendPayload(bytesmemory _payload) internalviewvirtualreturns (address to, uint64 amountSD) {
require(_payload.toUint8(0) == PT_SEND && _payload.length==41, "OFTCore: invalid payload");
to = _payload.toAddress(13); // drop the first 12 bytes of bytes32
amountSD = _payload.toUint64(33);
}
function_encodeSendAndCallPayload(address _from,
bytes32 _toAddress,
uint64 _amountSD,
bytesmemory _payload,
uint64 _dstGasForCall
) internalviewvirtualreturns (bytesmemory) {
returnabi.encodePacked(PT_SEND_AND_CALL, _toAddress, _amountSD, _addressToBytes32(_from), _dstGasForCall, _payload);
}
function_decodeSendAndCallPayload(bytesmemory _payload)
internalviewvirtualreturns (bytes32from,
address to,
uint64 amountSD,
bytesmemory payload,
uint64 dstGasForCall
)
{
require(_payload.toUint8(0) == PT_SEND_AND_CALL, "OFTCore: invalid payload");
to = _payload.toAddress(13); // drop the first 12 bytes of bytes32
amountSD = _payload.toUint64(33);
from= _payload.toBytes32(41);
dstGasForCall = _payload.toUint64(73);
payload = _payload.slice(81, _payload.length-81);
}
function_addressToBytes32(address _address) internalpurevirtualreturns (bytes32) {
returnbytes32(uint(uint160(_address)));
}
function_debitFrom(address _from,
uint16 _dstChainId,
bytes32 _toAddress,
uint _amount
) internalvirtualreturns (uint);
function_creditTo(uint16 _srcChainId,
address _toAddress,
uint _amount
) internalvirtualreturns (uint);
function_transferFrom(address _from,
address _to,
uint _amount
) internalvirtualreturns (uint);
function_ld2sdRate() internalviewvirtualreturns (uint);
}
Contract Source Code
File 20 of 22: Ownable.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.9.0) (access/Ownable.sol)pragmasolidity ^0.8.0;import"../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.
*/abstractcontractOwnableisContext{
addressprivate _owner;
eventOwnershipTransferred(addressindexed previousOwner, addressindexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/constructor() {
_transferOwnership(_msgSender());
}
/**
* @dev Throws if called by any account other than the owner.
*/modifieronlyOwner() {
_checkOwner();
_;
}
/**
* @dev Returns the address of the current owner.
*/functionowner() publicviewvirtualreturns (address) {
return _owner;
}
/**
* @dev Throws if the sender is not the owner.
*/function_checkOwner() internalviewvirtual{
require(owner() == _msgSender(), "Ownable: caller is not the owner");
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby disabling any functionality that is only available to the owner.
*/functionrenounceOwnership() publicvirtualonlyOwner{
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/functiontransferOwnership(address newOwner) publicvirtualonlyOwner{
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) internalvirtual{
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
Contract Source Code
File 21 of 22: ProxyOFTV2.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;import"./BaseOFTV2.sol";
import"@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
contractProxyOFTV2isBaseOFTV2{
usingSafeERC20forIERC20;
IERC20 internalimmutable innerToken;
uintinternalimmutable ld2sdRate;
// total amount is transferred from this chain to other chains, ensuring the total is less than uint64.max in sduintpublic outboundAmount;
constructor(address _token,
uint8 _sharedDecimals,
address _lzEndpoint
) BaseOFTV2(_sharedDecimals, _lzEndpoint) {
innerToken = IERC20(_token);
(bool success, bytesmemory data) = _token.staticcall(abi.encodeWithSignature("decimals()"));
require(success, "ProxyOFT: failed to get token decimals");
uint8 decimals =abi.decode(data, (uint8));
require(_sharedDecimals <= decimals, "ProxyOFT: sharedDecimals must be <= decimals");
ld2sdRate =10**(decimals - _sharedDecimals);
}
/************************************************************************
* public functions
************************************************************************/functioncirculatingSupply() publicviewvirtualoverridereturns (uint) {
return innerToken.totalSupply() - outboundAmount;
}
functiontoken() publicviewvirtualoverridereturns (address) {
returnaddress(innerToken);
}
/************************************************************************
* internal functions
************************************************************************/function_debitFrom(address _from,
uint16,
bytes32,
uint _amount
) internalvirtualoverridereturns (uint) {
require(_from == _msgSender(), "ProxyOFT: owner is not send caller");
_amount = _transferFrom(_from, address(this), _amount);
// _amount still may have dust if the token has transfer fee, then give the dust back to the sender
(uint amount, uint dust) = _removeDust(_amount);
if (dust >0) innerToken.safeTransfer(_from, dust);
// check total outbound amount
outboundAmount += amount;
uint cap = _sd2ld(type(uint64).max);
require(cap >= outboundAmount, "ProxyOFT: outboundAmount overflow");
return amount;
}
function_creditTo(uint16,
address _toAddress,
uint _amount
) internalvirtualoverridereturns (uint) {
outboundAmount -= _amount;
// tokens are already in this contract, so no need to transferif (_toAddress ==address(this)) {
return _amount;
}
return _transferFrom(address(this), _toAddress, _amount);
}
function_transferFrom(address _from,
address _to,
uint _amount
) internalvirtualoverridereturns (uint) {
uint before = innerToken.balanceOf(_to);
if (_from ==address(this)) {
innerToken.safeTransfer(_to, _amount);
} else {
innerToken.safeTransferFrom(_from, _to, _amount);
}
return innerToken.balanceOf(_to) - before;
}
function_ld2sdRate() internalviewvirtualoverridereturns (uint) {
return ld2sdRate;
}
}
Contract Source Code
File 22 of 22: SafeERC20.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.9.3) (token/ERC20/utils/SafeERC20.sol)pragmasolidity ^0.8.0;import"../IERC20.sol";
import"../extensions/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.
*/librarySafeERC20{
usingAddressforaddress;
/**
* @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/functionsafeTransfer(IERC20 token, address to, uint256 value) internal{
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
/**
* @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
* calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
*/functionsafeTransferFrom(IERC20 token, addressfrom, 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.
*/functionsafeApprove(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));
}
/**
* @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/functionsafeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal{
uint256 oldAllowance = token.allowance(address(this), spender);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
}
/**
* @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/functionsafeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal{
unchecked {
uint256 oldAllowance = token.allowance(address(this), spender);
require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
}
}
/**
* @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
* to be set to zero before setting it to a non-zero value, such as USDT.
*/functionforceApprove(IERC20 token, address spender, uint256 value) internal{
bytesmemory approvalCall =abi.encodeWithSelector(token.approve.selector, spender, value);
if (!_callOptionalReturnBool(token, approvalCall)) {
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
_callOptionalReturn(token, approvalCall);
}
}
/**
* @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
* Revert on invalid signature.
*/functionsafePermit(
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, bytesmemory 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.bytesmemory returndata =address(token).functionCall(data, "SafeERC20: low-level call failed");
require(returndata.length==0||abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation 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).
*
* This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
*/function_callOptionalReturnBool(IERC20 token, bytesmemory data) privatereturns (bool) {
// 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 cannot use {Address-functionCall} here since this should return false// and not revert is the subcall reverts.
(bool success, bytesmemory returndata) =address(token).call(data);
return
success && (returndata.length==0||abi.decode(returndata, (bool))) && Address.isContract(address(token));
}
}