Contract Name:
SignatureMerkleDrop128
Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity 0.8.15;
pragma abicoder v1;
import "@openzeppelin/contracts/utils/math/Math.sol";
import "@openzeppelin/contracts/utils/Address.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@1inch/solidity-utils/contracts/libraries/SafeERC20.sol";
import "@1inch/solidity-utils/contracts/libraries/ECDSA.sol";
import "./interfaces/ISignatureMerkleDrop128.sol";
contract SignatureMerkleDrop128 is ISignatureMerkleDrop128, Ownable {
using Address for address payable;
using SafeERC20 for IERC20;
address public immutable override token;
bytes16 public immutable override merkleRoot;
uint256 public immutable override depth;
// This is a packed array of booleans.
mapping(uint256 => uint256) private _claimedBitMap;
uint256 private constant _CLAIM_GAS_COST = 60000;
receive() external payable {} // solhint-disable-line no-empty-blocks
constructor(address token_, bytes16 merkleRoot_, uint256 depth_) {
token = token_;
merkleRoot = merkleRoot_;
depth = depth_;
}
function claim(address receiver, uint256 amount, bytes calldata merkleProof, bytes calldata signature) external override {
bytes32 signedHash = ECDSA.toEthSignedMessageHash(keccak256(abi.encodePacked(receiver)));
address account = ECDSA.recover(signedHash, signature);
// Verify the merkle proof.
bytes16 node = bytes16(keccak256(abi.encodePacked(account, amount)));
(bool valid, uint256 index) = _verifyAsm(merkleProof, merkleRoot, node);
require(valid, "MD: Invalid proof");
_invalidate(index);
IERC20(token).safeTransfer(receiver, amount);
_cashback();
}
function verify(bytes calldata proof, bytes16 root, bytes16 leaf) external view returns (bool valid, uint256 index) {
return _verifyAsm(proof, root, leaf);
}
function verify(bytes calldata proof, bytes16 leaf) external view returns (bool valid, uint256 index) {
return _verifyAsm(proof, merkleRoot, leaf);
}
function isClaimed(uint256 index) external view override returns (bool) {
uint256 claimedWordIndex = index / 256;
uint256 claimedBitIndex = index % 256;
uint256 claimedWord = _claimedBitMap[claimedWordIndex];
uint256 mask = (1 << claimedBitIndex);
return claimedWord & mask == mask;
}
function _cashback() private {
uint256 balance = address(this).balance;
if (balance > 0) {
// solhint-disable-next-line avoid-tx-origin
payable(tx.origin).sendValue(Math.min(block.basefee * _CLAIM_GAS_COST, balance));
}
}
function _invalidate(uint256 index) private {
uint256 claimedWordIndex = index >> 8;
uint256 claimedBitIndex = index & 0xff;
uint256 claimedWord = _claimedBitMap[claimedWordIndex];
uint256 newClaimedWord = claimedWord | (1 << claimedBitIndex);
require(claimedWord != newClaimedWord, "MD: Drop already claimed");
_claimedBitMap[claimedWordIndex] = newClaimedWord;
}
function _verifyAsm(bytes calldata proof, bytes16 root, bytes16 leaf) private view returns (bool valid, uint256 index) {
/// @solidity memory-safe-assembly
assembly { // solhint-disable-line no-inline-assembly
let ptr := proof.offset
let mask := 1
for { let end := add(ptr, proof.length) } lt(ptr, end) { ptr := add(ptr, 0x10) } {
let node := calldataload(ptr)
switch lt(leaf, node)
case 1 {
mstore(0x00, leaf)
mstore(0x10, node)
}
default {
mstore(0x00, node)
mstore(0x10, leaf)
index := or(mask, index)
}
leaf := keccak256(0x00, 0x20)
mask := shl(1, mask)
}
valid := iszero(shr(128, xor(root, leaf)))
}
unchecked {
index <<= depth - proof.length / 16;
}
}
function rescueFunds(address token_, uint256 amount) external onlyOwner {
if (token_ == address(0)) {
payable(msg.sender).sendValue(amount);
} else {
IERC20(token_).safeTransfer(msg.sender, amount);
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/math/Math.sol)
pragma solidity ^0.8.0;
/**
* @dev Standard math utilities missing in the Solidity language.
*/
library Math {
/**
* @dev Returns the largest of two numbers.
*/
function max(uint256 a, uint256 b) internal pure returns (uint256) {
return a >= b ? a : b;
}
/**
* @dev Returns the smallest of two numbers.
*/
function min(uint256 a, uint256 b) internal pure returns (uint256) {
return a < b ? a : b;
}
/**
* @dev Returns the average of two numbers. The result is rounded towards
* zero.
*/
function average(uint256 a, uint256 b) internal pure returns (uint256) {
// (a + b) / 2 can overflow.
return (a & b) + (a ^ b) / 2;
}
/**
* @dev Returns the ceiling of the division of two numbers.
*
* This differs from standard division with `/` in that it rounds up instead
* of rounding down.
*/
function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
// (a + b - 1) / b can overflow on addition, so we distribute.
return a / b + (a % b == 0 ? 0 : 1);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (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
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)
pragma solidity ^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.
*/
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 Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public 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
pragma solidity ^0.8.0;
pragma abicoder v1;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/extensions/draft-IERC20Permit.sol";
import "../interfaces/IDaiLikePermit.sol";
import "../libraries/RevertReasonForwarder.sol";
library SafeERC20 {
error SafeTransferFailed();
error SafeTransferFromFailed();
error ForceApproveFailed();
error SafeIncreaseAllowanceFailed();
error SafeDecreaseAllowanceFailed();
error SafePermitBadLength();
// Ensures method do not revert or return boolean `true`, admits call to non-smart-contract
function safeTransferFrom(IERC20 token, address from, address to, uint256 amount) internal {
bytes4 selector = token.transferFrom.selector;
bool success;
/// @solidity memory-safe-assembly
assembly { // solhint-disable-line no-inline-assembly
let data := mload(0x40)
mstore(data, selector)
mstore(add(data, 0x04), from)
mstore(add(data, 0x24), to)
mstore(add(data, 0x44), amount)
let status := call(gas(), token, 0, data, 100, 0x0, 0x20)
success := and(status, or(iszero(returndatasize()), and(gt(returndatasize(), 31), eq(mload(0), 1))))
}
if (!success) {
revert SafeTransferFromFailed();
}
}
// Ensures method do not revert or return boolean `true`, admits call to non-smart-contract
function safeTransfer(IERC20 token, address to, uint256 value) internal {
if (!_makeCall(token, token.transfer.selector, to, value)) {
revert SafeTransferFailed();
}
}
// If `approve(from, to, amount)` fails, try to `approve(from, to, 0)` before retry
function forceApprove(IERC20 token, address spender, uint256 value) internal {
if (!_makeCall(token, token.approve.selector, spender, value)) {
if (!_makeCall(token, token.approve.selector, spender, 0) ||
!_makeCall(token, token.approve.selector, spender, value))
{
revert ForceApproveFailed();
}
}
}
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 allowance = token.allowance(address(this), spender);
if (value > type(uint256).max - allowance) revert SafeIncreaseAllowanceFailed();
forceApprove(token, spender, allowance + value);
}
function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 allowance = token.allowance(address(this), spender);
if (value > allowance) revert SafeDecreaseAllowanceFailed();
forceApprove(token, spender, allowance - value);
}
function safePermit(IERC20 token, bytes calldata permit) internal {
bool success;
if (permit.length == 32 * 7) {
// solhint-disable-next-line avoid-low-level-calls
success = _makeCalldataCall(token, IERC20Permit.permit.selector, permit);
} else if (permit.length == 32 * 8) {
// solhint-disable-next-line avoid-low-level-calls
success = _makeCalldataCall(token, IDaiLikePermit.permit.selector, permit);
} else {
revert SafePermitBadLength();
}
if (!success) {
RevertReasonForwarder.reRevert();
}
}
function _makeCall(IERC20 token, bytes4 selector, address to, uint256 amount) private returns(bool done) {
/// @solidity memory-safe-assembly
assembly { // solhint-disable-line no-inline-assembly
let data := mload(0x40)
mstore(data, selector)
mstore(add(data, 0x04), to)
mstore(add(data, 0x24), amount)
let success := call(gas(), token, 0, data, 68, 0x0, 0x20)
done := and(
success,
or(
iszero(returndatasize()),
and(gt(returndatasize(), 31), eq(mload(0), 1))
)
)
}
}
function _makeCalldataCall(IERC20 token, bytes4 selector, bytes calldata args) private returns(bool done) {
/// @solidity memory-safe-assembly
assembly { // solhint-disable-line no-inline-assembly
let len := add(4, args.length)
let data := mload(0x40)
mstore(data, selector)
calldatacopy(add(data, 0x04), args.offset, args.length)
let success := call(gas(), token, 0, data, len, 0x0, 0x20)
done := and(
success,
or(
iszero(returndatasize()),
and(gt(returndatasize(), 31), eq(mload(0), 1))
)
)
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
pragma abicoder v1;
import "@openzeppelin/contracts/interfaces/IERC1271.sol";
library ECDSA {
function recover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal view returns(address signer) {
/// @solidity memory-safe-assembly
assembly { // solhint-disable-line no-inline-assembly
let ptr := mload(0x40)
mstore(ptr, hash)
mstore(add(ptr, 0x20), v)
mstore(add(ptr, 0x40), r)
mstore(add(ptr, 0x60), s)
if staticcall(gas(), 0x1, ptr, 0x80, 0, 0x20) {
signer := mload(0)
}
}
}
function recover(bytes32 hash, bytes32 r, bytes32 vs) internal view returns(address signer) {
/// @solidity memory-safe-assembly
assembly { // solhint-disable-line no-inline-assembly
let ptr := mload(0x40)
mstore(ptr, hash)
mstore(add(ptr, 0x20), add(27, shr(255, vs)))
mstore(add(ptr, 0x40), r)
mstore(add(ptr, 0x60), shr(1, shl(1, vs)))
if staticcall(gas(), 0x1, ptr, 0x80, 0, 0x20) {
signer := mload(0)
}
}
}
function recover(bytes32 hash, bytes calldata signature) internal view returns(address signer) {
/// @solidity memory-safe-assembly
assembly { // solhint-disable-line no-inline-assembly
let ptr := mload(0x40)
// memory[ptr:ptr+0x80] = (hash, v, r, s)
switch signature.length
case 65 {
// memory[ptr+0x20:ptr+0x80] = (v, r, s)
mstore(add(ptr, 0x20), byte(0, calldataload(add(signature.offset, 0x40))))
calldatacopy(add(ptr, 0x40), signature.offset, 0x40)
}
case 64 {
// memory[ptr+0x20:ptr+0x80] = (v, r, s)
let vs := calldataload(add(signature.offset, 0x20))
mstore(add(ptr, 0x20), add(27, shr(255, vs)))
calldatacopy(add(ptr, 0x40), signature.offset, 0x20)
mstore(add(ptr, 0x60), shr(1, shl(1, vs)))
}
default {
ptr := 0
}
if ptr {
if gt(mload(add(ptr, 0x60)), 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
ptr := 0
}
if ptr {
// memory[ptr:ptr+0x20] = (hash)
mstore(ptr, hash)
if staticcall(gas(), 0x1, ptr, 0x80, 0, 0x20) {
signer := mload(0)
}
}
}
}
}
function recoverOrIsValidSignature(address signer, bytes32 hash, bytes calldata signature) internal view returns(bool success) {
if ((signature.length == 64 || signature.length == 65) && recover(hash, signature) == signer) {
return true;
}
return isValidSignature(signer, hash, signature);
}
function recoverOrIsValidSignature(address signer, bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal view returns(bool success) {
if (recover(hash, v, r, s) == signer) {
return true;
}
return isValidSignature(signer, hash, v, r, s);
}
function recoverOrIsValidSignature(address signer, bytes32 hash, bytes32 r, bytes32 vs) internal view returns(bool success) {
if (recover(hash, r, vs) == signer) {
return true;
}
return isValidSignature(signer, hash, r, vs);
}
function recoverOrIsValidSignature65(address signer, bytes32 hash, bytes32 r, bytes32 vs) internal view returns(bool success) {
if (recover(hash, r, vs) == signer) {
return true;
}
return isValidSignature65(signer, hash, r, vs);
}
function isValidSignature(address signer, bytes32 hash, bytes calldata signature) internal view returns(bool success) {
// (bool success, bytes memory data) = signer.staticcall(abi.encodeWithSelector(IERC1271.isValidSignature.selector, hash, signature));
// return success && data.length >= 4 && abi.decode(data, (bytes4)) == IERC1271.isValidSignature.selector;
bytes4 selector = IERC1271.isValidSignature.selector;
/// @solidity memory-safe-assembly
assembly { // solhint-disable-line no-inline-assembly
let ptr := mload(0x40)
let len := add(0x64, signature.length)
mstore(ptr, selector)
mstore(add(ptr, 0x04), hash)
mstore(add(ptr, 0x24), 0x40)
mstore(add(ptr, 0x44), signature.length)
calldatacopy(add(ptr, 0x64), signature.offset, signature.length)
mstore(0, 0)
if staticcall(gas(), signer, ptr, len, 0, 0x20) {
success := eq(selector, mload(0))
}
}
}
function isValidSignature(address signer, bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal view returns(bool success) {
bytes4 selector = IERC1271.isValidSignature.selector;
/// @solidity memory-safe-assembly
assembly { // solhint-disable-line no-inline-assembly
let ptr := mload(0x40)
let len := add(0x64, 65)
mstore(ptr, selector)
mstore(add(ptr, 0x04), hash)
mstore(add(ptr, 0x24), 0x40)
mstore(add(ptr, 0x44), 65)
mstore(add(ptr, 0x64), r)
mstore(add(ptr, 0x84), s)
mstore8(add(ptr, 0xa4), v)
mstore(0, 0)
if staticcall(gas(), signer, ptr, len, 0, 0x20) {
success := eq(selector, mload(0))
}
}
}
function isValidSignature(address signer, bytes32 hash, bytes32 r, bytes32 vs) internal view returns(bool success) {
// (bool success, bytes memory data) = signer.staticcall(abi.encodeWithSelector(IERC1271.isValidSignature.selector, hash, abi.encodePacked(r, vs)));
// return success && data.length >= 4 && abi.decode(data, (bytes4)) == IERC1271.isValidSignature.selector;
bytes4 selector = IERC1271.isValidSignature.selector;
/// @solidity memory-safe-assembly
assembly { // solhint-disable-line no-inline-assembly
let ptr := mload(0x40)
let len := add(0x64, 64)
mstore(ptr, selector)
mstore(add(ptr, 0x04), hash)
mstore(add(ptr, 0x24), 0x40)
mstore(add(ptr, 0x44), 64)
mstore(add(ptr, 0x64), r)
mstore(add(ptr, 0x84), vs)
mstore(0, 0)
if staticcall(gas(), signer, ptr, len, 0, 0x20) {
success := eq(selector, mload(0))
}
}
}
function isValidSignature65(address signer, bytes32 hash, bytes32 r, bytes32 vs) internal view returns(bool success) {
// (bool success, bytes memory data) = signer.staticcall(abi.encodeWithSelector(IERC1271.isValidSignature.selector, hash, abi.encodePacked(r, vs & ~uint256(1 << 255), uint8(vs >> 255))));
// return success && data.length >= 4 && abi.decode(data, (bytes4)) == IERC1271.isValidSignature.selector;
bytes4 selector = IERC1271.isValidSignature.selector;
/// @solidity memory-safe-assembly
assembly { // solhint-disable-line no-inline-assembly
let ptr := mload(0x40)
let len := add(0x64, 65)
mstore(ptr, selector)
mstore(add(ptr, 0x04), hash)
mstore(add(ptr, 0x24), 0x40)
mstore(add(ptr, 0x44), 65)
mstore(add(ptr, 0x64), r)
mstore(add(ptr, 0x84), shr(1, shl(1, vs)))
mstore8(add(ptr, 0xa4), add(27, shr(255, vs)))
mstore(0, 0)
if staticcall(gas(), signer, ptr, len, 0, 0x20) {
success := eq(selector, mload(0))
}
}
}
function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32 res) {
// 32 is the length in bytes of hash, enforced by the type signature above
// return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
/// @solidity memory-safe-assembly
assembly { // solhint-disable-line no-inline-assembly
mstore(0, 0x19457468657265756d205369676e6564204d6573736167653a0a333200000000) // "\x19Ethereum Signed Message:\n32"
mstore(28, hash)
res := keccak256(0, 60)
}
}
function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32 res) {
// return keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
/// @solidity memory-safe-assembly
assembly { // solhint-disable-line no-inline-assembly
let ptr := mload(0x40)
mstore(ptr, 0x1901000000000000000000000000000000000000000000000000000000000000) // "\x19\x01"
mstore(add(ptr, 0x02), domainSeparator)
mstore(add(ptr, 0x22), structHash)
res := keccak256(ptr, 66)
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
pragma abicoder v1;
// Allows anyone to claim a token if they exist in a merkle root.
interface ISignatureMerkleDrop128 {
// Returns the address of the token distributed by this contract.
function token() external view returns (address);
// Returns the merkle root of the merkle tree containing account balances available to claim.
function merkleRoot() external view returns (bytes16);
// Returns the tree depth of the merkle tree containing account balances available to claim.
function depth() external view returns (uint256);
// Claim the given amount of the token to the given address. Reverts if the inputs are invalid.
function claim(address receiver, uint256 amount, bytes calldata merkleProof, bytes calldata signature) external;
// Verifies that given leaf and merkle proof matches given merkle root and returns leaf index.
function verify(bytes calldata proof, bytes16 root, bytes16 leaf) external view returns (bool valid, uint256 index);
// Returns true if the index has been marked claimed.
function isClaimed(uint256 index) external view returns (bool);
}
// 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 v4.6.0) (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);
}
// 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
pragma solidity ^0.8.0;
pragma abicoder v1;
interface IDaiLikePermit {
function permit(address holder, address spender, uint256 nonce, uint256 expiry, bool allowed, uint8 v, bytes32 r, bytes32 s) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
pragma abicoder v1;
library RevertReasonForwarder {
function reRevert() internal pure {
// bubble up revert reason from latest external call
/// @solidity memory-safe-assembly
assembly { // solhint-disable-line no-inline-assembly
let ptr := mload(0x40)
returndatacopy(ptr, 0, returndatasize())
revert(ptr, returndatasize())
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (interfaces/IERC1271.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC1271 standard signature validation method for
* contracts as defined in https://eips.ethereum.org/EIPS/eip-1271[ERC-1271].
*
* _Available since v4.1._
*/
interface IERC1271 {
/**
* @dev Should return whether the signature provided is valid for the provided data
* @param hash Hash of the data to be signed
* @param signature Signature byte array associated with _data
*/
function isValidSignature(bytes32 hash, bytes memory signature) external view returns (bytes4 magicValue);
}