/
MetaContext.sol
36 lines (30 loc) · 1.16 KB
/
MetaContext.sol
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//SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/access/Ownable.sol";
contract MetaContext is Ownable {
mapping(address => bool) private _isTrustedForwarder;
function setTrustedForwarder(address _forwarder, bool _bool) external onlyOwner {
_isTrustedForwarder[_forwarder] = _bool;
}
function isTrustedForwarder(address _forwarder) external view returns (bool) {
return _isTrustedForwarder[_forwarder];
}
function _msgSender() internal view virtual override returns (address sender) {
if (_isTrustedForwarder[msg.sender]) {
// The assembly code is more direct than the Solidity version using `abi.decode`.
/// @solidity memory-safe-assembly
assembly {
sender := shr(96, calldataload(sub(calldatasize(), 20)))
}
} else {
return super._msgSender();
}
}
function _msgData() internal view virtual override returns (bytes calldata) {
if (_isTrustedForwarder[msg.sender]) {
return msg.data[:msg.data.length - 20];
} else {
return super._msgData();
}
}
}