// SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.9.4) (metatx/ERC2771Context.sol) pragma solidity ^0.8.9; import "../utils/Context.sol"; /** * @dev Context variant with ERC2771 support. * * WARNING: The usage of `delegatecall` in this contract is dangerous and may result in context corruption. * Any forwarded request to this contract triggering a `delegatecall` to itself will result in an invalid {_msgSender} * recovery. */ abstract contract ERC2771Context is Context { /// @custom:oz-upgrades-unsafe-allow state-variable-immutable address private immutable _trustedForwarder; /// @custom:oz-upgrades-unsafe-allow constructor constructor(address trustedForwarder) { _trustedForwarder = trustedForwarder; } function isTrustedForwarder(address forwarder) public view virtual returns (bool) { return forwarder == _trustedForwarder; } function _msgSender() internal view virtual override returns (address) { uint256 calldataLength = msg.data.length; uint256 contextSuffixLength = _contextSuffixLength(); if (isTrustedForwarder(msg.sender) && calldataLength >= contextSuffixLength) { return address(bytes20(msg.data[calldataLength - contextSuffixLength:])); } else { return super._msgSender(); } } function _msgData() internal view virtual override returns (bytes calldata) { uint256 calldataLength = msg.data.length; uint256 contextSuffixLength = _contextSuffixLength(); if (isTrustedForwarder(msg.sender) && calldataLength >= contextSuffixLength) { return msg.data[:calldataLength - contextSuffixLength]; } else { return super._msgData(); } } /** * @dev ERC-2771 specifies the context as being a single address (20 bytes). */ function _contextSuffixLength() internal view virtual override returns (uint256) { return 20; } }