// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
pragma solidity ^0.8.1;
/**
* @dev Collection of functions related to the address type
*/
library AddressUpgradeable {
/**
* @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 Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason using the provided one.
*
* _Available since v4.3._
*/
function verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) internal pure returns (bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
/// @solidity memory-safe-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/cryptography/ECDSA.sol)
pragma solidity ^0.8.0;
import "../StringsUpgradeable.sol";
/**
* @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
*
* These functions can be used to verify that a message was signed by the holder
* of the private keys of a given address.
*/
library ECDSAUpgradeable {
enum RecoverError {
NoError,
InvalidSignature,
InvalidSignatureLength,
InvalidSignatureS,
InvalidSignatureV
}
function _throwError(RecoverError error) private pure {
if (error == RecoverError.NoError) {
return; // no error: do nothing
} else if (error == RecoverError.InvalidSignature) {
revert("ECDSA: invalid signature");
} else if (error == RecoverError.InvalidSignatureLength) {
revert("ECDSA: invalid signature length");
} else if (error == RecoverError.InvalidSignatureS) {
revert("ECDSA: invalid signature 's' value");
} else if (error == RecoverError.InvalidSignatureV) {
revert("ECDSA: invalid signature 'v' value");
}
}
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature` or error string. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*
* Documentation for signature generation:
* - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
* - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
*
* _Available since v4.3._
*/
function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
// Check the signature length
// - case 65: r,s,v signature (standard)
// - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._
if (signature.length == 65) {
bytes32 r;
bytes32 s;
uint8 v;
// ecrecover takes the signature parameters, and the only way to get them
// currently is to use assembly.
/// @solidity memory-safe-assembly
assembly {
r := mload(add(signature, 0x20))
s := mload(add(signature, 0x40))
v := byte(0, mload(add(signature, 0x60)))
}
return tryRecover(hash, v, r, s);
} else if (signature.length == 64) {
bytes32 r;
bytes32 vs;
// ecrecover takes the signature parameters, and the only way to get them
// currently is to use assembly.
/// @solidity memory-safe-assembly
assembly {
r := mload(add(signature, 0x20))
vs := mload(add(signature, 0x40))
}
return tryRecover(hash, r, vs);
} else {
return (address(0), RecoverError.InvalidSignatureLength);
}
}
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature`. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*/
function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, signature);
_throwError(error);
return recovered;
}
/**
* @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
*
* See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
*
* _Available since v4.3._
*/
function tryRecover(
bytes32 hash,
bytes32 r,
bytes32 vs
) internal pure returns (address, RecoverError) {
bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
uint8 v = uint8((uint256(vs) >> 255) + 27);
return tryRecover(hash, v, r, s);
}
/**
* @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
*
* _Available since v4.2._
*/
function recover(
bytes32 hash,
bytes32 r,
bytes32 vs
) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, r, vs);
_throwError(error);
return recovered;
}
/**
* @dev Overload of {ECDSA-tryRecover} that receives the `v`,
* `r` and `s` signature fields separately.
*
* _Available since v4.3._
*/
function tryRecover(
bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internal pure returns (address, RecoverError) {
// EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
// unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
// the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
// signatures from current libraries generate a unique signature with an s-value in the lower half order.
//
// If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
// with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
// vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
// these malleable signatures as well.
if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
return (address(0), RecoverError.InvalidSignatureS);
}
if (v != 27 && v != 28) {
return (address(0), RecoverError.InvalidSignatureV);
}
// If the signature is valid (and not malleable), return the signer address
address signer = ecrecover(hash, v, r, s);
if (signer == address(0)) {
return (address(0), RecoverError.InvalidSignature);
}
return (signer, RecoverError.NoError);
}
/**
* @dev Overload of {ECDSA-recover} that receives the `v`,
* `r` and `s` signature fields separately.
*/
function recover(
bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, v, r, s);
_throwError(error);
return recovered;
}
/**
* @dev Returns an Ethereum Signed Message, created from a `hash`. This
* produces hash corresponding to the one signed with the
* https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
* JSON-RPC method as part of EIP-191.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
// 32 is the length in bytes of hash,
// enforced by the type signature above
return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
}
/**
* @dev Returns an Ethereum Signed Message, created from `s`. This
* produces hash corresponding to the one signed with the
* https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
* JSON-RPC method as part of EIP-191.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", StringsUpgradeable.toString(s.length), s));
}
/**
* @dev Returns an Ethereum Signed Typed Data, created from a
* `domainSeparator` and a `structHash`. This produces hash corresponding
* to the one signed with the
* https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
* JSON-RPC method as part of EIP-712.
*
* See {recover}.
*/
function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
return keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (metatx/MinimalForwarder.sol)
pragma solidity ^0.8.0;
import "../lib/openzeppelin-contracts-upgradeable/contracts/utils/cryptography/ECDSAUpgradeable.sol";
import "../lib/openzeppelin-contracts-upgradeable/contracts/utils/cryptography/draft-EIP712Upgradeable.sol";
import "../lib/openzeppelin-contracts-upgradeable/contracts/proxy/utils/Initializable.sol";
/**
* @dev Simple minimal forwarder to be used together with an ERC2771 compatible contract. See {ERC2771Context}.
*
* MinimalForwarder is mainly meant for testing, as it is missing features to be a good production-ready forwarder. This
* contract does not intend to have all the properties that are needed for a sound forwarding system. A fully
* functioning forwarding system with good properties requires more complexity. We suggest you look at other projects
* such as the GSN which do have the goal of building a system like that.
*/
contract FranklinForwarder is Initializable, EIP712Upgradeable {
using ECDSAUpgradeable for bytes32;
struct ForwardRequest {
address from;
address to;
uint256 value;
uint256 gas;
uint256 nonce;
bytes data;
}
bytes32 private constant _TYPEHASH =
keccak256(
"ForwardRequest(address from,address to,uint256 value,uint256 gas,uint256 nonce,bytes data)"
);
mapping(address => uint256) private _nonces;
constructor() initializer {
__MinimalForwarder_init();
}
function __MinimalForwarder_init() internal onlyInitializing {
__EIP712_init_unchained("Franklin", "0.0.1");
}
function __MinimalForwarder_init_unchained() internal onlyInitializing {}
function getNonce(address from) public view returns (uint256) {
return _nonces[from];
}
function verify(ForwardRequest calldata req, bytes calldata signature)
public
view
returns (bool)
{
address signer = _hashTypedDataV4(
keccak256(
abi.encode(
_TYPEHASH,
req.from,
req.to,
req.value,
req.gas,
req.nonce,
keccak256(req.data)
)
)
).recover(signature);
return _nonces[req.from] == req.nonce && signer == req.from;
}
function execute(ForwardRequest calldata req, bytes calldata signature)
public
payable
returns (bool, bytes memory)
{
require(
verify(req, signature),
"MinimalForwarder: signature does not match request"
);
_nonces[req.from] = req.nonce + 1;
(bool success, bytes memory returndata) = req.to.call{
gas: req.gas,
value: req.value
}(abi.encodePacked(req.data, req.from));
// point of concern. If the req.value is larger than the msg.value, the forwarder will send more value to the contract than was sent to the forwarder
// Validate that the relayer has sent enough gas for the call.
// See https://ronan.eth.link/blog/ethereum-gas-dangers/
if (gasleft() <= req.gas / 63) {
// We explicitly trigger invalid opcode to consume all gas and bubble-up the effects, since
// neither revert or assert consume all gas since Solidity 0.8.0
// https://docs.soliditylang.org/en/v0.8.0/control-structures.html#panic-via-assert-and-error-via-require
/// @solidity memory-safe-assembly
assembly {
invalid()
}
}
return (success, returndata);
}
/**
* @dev This empty reserved space is put in place to allow future versions to add new
* variables without shifting down storage in the inheritance chain.
* See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
*/
uint256[49] private __gap;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (proxy/utils/Initializable.sol)
pragma solidity ^0.8.2;
import "../../utils/AddressUpgradeable.sol";
/**
* @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
* behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
* external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
* function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
*
* The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
* reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
* case an upgrade adds a module that needs to be initialized.
*
* For example:
*
* [.hljs-theme-light.nopadding]
* ```
* contract MyToken is ERC20Upgradeable {
* function initialize() initializer public {
* __ERC20_init("MyToken", "MTK");
* }
* }
* contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
* function initializeV2() reinitializer(2) public {
* __ERC20Permit_init("MyToken");
* }
* }
* ```
*
* TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
* possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
*
* CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
* that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
*
* [CAUTION]
* ====
* Avoid leaving a contract uninitialized.
*
* An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
* contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
* the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
*
* [.hljs-theme-light.nopadding]
* ```
* /// @custom:oz-upgrades-unsafe-allow constructor
* constructor() {
* _disableInitializers();
* }
* ```
* ====
*/
abstract contract Initializable {
/**
* @dev Indicates that the contract has been initialized.
* @custom:oz-retyped-from bool
*/
uint8 private _initialized;
/**
* @dev Indicates that the contract is in the process of being initialized.
*/
bool private _initializing;
/**
* @dev Triggered when the contract has been initialized or reinitialized.
*/
event Initialized(uint8 version);
/**
* @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
* `onlyInitializing` functions can be used to initialize parent contracts. Equivalent to `reinitializer(1)`.
*/
modifier initializer() {
bool isTopLevelCall = !_initializing;
require(
(isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
"Initializable: contract is already initialized"
);
_initialized = 1;
if (isTopLevelCall) {
_initializing = true;
}
_;
if (isTopLevelCall) {
_initializing = false;
emit Initialized(1);
}
}
/**
* @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
* contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
* used to initialize parent contracts.
*
* `initializer` is equivalent to `reinitializer(1)`, so a reinitializer may be used after the original
* initialization step. This is essential to configure modules that are added through upgrades and that require
* initialization.
*
* Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
* a contract, executing them in the right order is up to the developer or operator.
*/
modifier reinitializer(uint8 version) {
require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
_initialized = version;
_initializing = true;
_;
_initializing = false;
emit Initialized(version);
}
/**
* @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
* {initializer} and {reinitializer} modifiers, directly or indirectly.
*/
modifier onlyInitializing() {
require(_initializing, "Initializable: contract is not initializing");
_;
}
/**
* @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
* Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
* to any version. It is recommended to use this to lock implementation contracts that are designed to be called
* through proxies.
*/
function _disableInitializers() internal virtual {
require(!_initializing, "Initializable: contract is initializing");
if (_initialized < type(uint8).max) {
_initialized = type(uint8).max;
emit Initialized(type(uint8).max);
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Strings.sol)
pragma solidity ^0.8.0;
/**
* @dev String operations.
*/
library StringsUpgradeable {
bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
uint8 private constant _ADDRESS_LENGTH = 20;
/**
* @dev Converts a `uint256` to its ASCII `string` decimal representation.
*/
function toString(uint256 value) internal pure returns (string memory) {
// Inspired by OraclizeAPI's implementation - MIT licence
// https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
if (value == 0) {
return "0";
}
uint256 temp = value;
uint256 digits;
while (temp != 0) {
digits++;
temp /= 10;
}
bytes memory buffer = new bytes(digits);
while (value != 0) {
digits -= 1;
buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
value /= 10;
}
return string(buffer);
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
*/
function toHexString(uint256 value) internal pure returns (string memory) {
if (value == 0) {
return "0x00";
}
uint256 temp = value;
uint256 length = 0;
while (temp != 0) {
length++;
temp >>= 8;
}
return toHexString(value, length);
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
*/
function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
bytes memory buffer = new bytes(2 * length + 2);
buffer[0] = "0";
buffer[1] = "x";
for (uint256 i = 2 * length + 1; i > 1; --i) {
buffer[i] = _HEX_SYMBOLS[value & 0xf];
value >>= 4;
}
require(value == 0, "Strings: hex length insufficient");
return string(buffer);
}
/**
* @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
*/
function toHexString(address addr) internal pure returns (string memory) {
return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/cryptography/draft-EIP712.sol)
pragma solidity ^0.8.0;
import "./ECDSAUpgradeable.sol";
import "../../proxy/utils/Initializable.sol";
/**
* @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
*
* The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
* thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
* they need in their contracts using a combination of `abi.encode` and `keccak256`.
*
* This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
* scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
* ({_hashTypedDataV4}).
*
* The implementation of the domain separator was designed to be as efficient as possible while still properly updating
* the chain id to protect against replay attacks on an eventual fork of the chain.
*
* NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
* https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
*
* _Available since v3.4._
*
* @custom:storage-size 52
*/
abstract contract EIP712Upgradeable is Initializable {
/* solhint-disable var-name-mixedcase */
bytes32 private _HASHED_NAME;
bytes32 private _HASHED_VERSION;
bytes32 private constant _TYPE_HASH = keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
/* solhint-enable var-name-mixedcase */
/**
* @dev Initializes the domain separator and parameter caches.
*
* The meaning of `name` and `version` is specified in
* https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
*
* - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
* - `version`: the current major version of the signing domain.
*
* NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
* contract upgrade].
*/
function __EIP712_init(string memory name, string memory version) internal onlyInitializing {
__EIP712_init_unchained(name, version);
}
function __EIP712_init_unchained(string memory name, string memory version) internal onlyInitializing {
bytes32 hashedName = keccak256(bytes(name));
bytes32 hashedVersion = keccak256(bytes(version));
_HASHED_NAME = hashedName;
_HASHED_VERSION = hashedVersion;
}
/**
* @dev Returns the domain separator for the current chain.
*/
function _domainSeparatorV4() internal view returns (bytes32) {
return _buildDomainSeparator(_TYPE_HASH, _EIP712NameHash(), _EIP712VersionHash());
}
function _buildDomainSeparator(
bytes32 typeHash,
bytes32 nameHash,
bytes32 versionHash
) private view returns (bytes32) {
return keccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this)));
}
/**
* @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
* function returns the hash of the fully encoded EIP712 message for this domain.
*
* This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
*
* ```solidity
* bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
* keccak256("Mail(address to,string contents)"),
* mailTo,
* keccak256(bytes(mailContents))
* )));
* address signer = ECDSA.recover(digest, signature);
* ```
*/
function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
return ECDSAUpgradeable.toTypedDataHash(_domainSeparatorV4(), structHash);
}
/**
* @dev The hash of the name parameter for the EIP712 domain.
*
* NOTE: This function reads from storage by default, but can be redefined to return a constant value if gas costs
* are a concern.
*/
function _EIP712NameHash() internal virtual view returns (bytes32) {
return _HASHED_NAME;
}
/**
* @dev The hash of the version parameter for the EIP712 domain.
*
* NOTE: This function reads from storage by default, but can be redefined to return a constant value if gas costs
* are a concern.
*/
function _EIP712VersionHash() internal virtual view returns (bytes32) {
return _HASHED_VERSION;
}
/**
* @dev This empty reserved space is put in place to allow future versions to add new
* variables without shifting down storage in the inheritance chain.
* See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
*/
uint256[50] private __gap;
}
{
"compilationTarget": {
"src/FranklinForwarder.sol": "FranklinForwarder"
},
"evmVersion": "london",
"libraries": {},
"metadata": {
"bytecodeHash": "ipfs"
},
"optimizer": {
"enabled": true,
"runs": 200
},
"remappings": [
":@oz/=lib/openzeppelin-contracts/",
":@upgradeable-oz/=lib/openzeppelin-contracts-upgradeable/",
":ds-test/=lib/forge-std/lib/ds-test/src/",
":forge-std/=lib/forge-std/src/",
":openzeppelin-contracts-upgradeable/=lib/openzeppelin-contracts-upgradeable/",
":openzeppelin-contracts/=lib/openzeppelin-contracts/"
]
}
[{"inputs":[],"stateMutability":"nonpayable","type":"constructor"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"uint8","name":"version","type":"uint8"}],"name":"Initialized","type":"event"},{"inputs":[{"components":[{"internalType":"address","name":"from","type":"address"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"value","type":"uint256"},{"internalType":"uint256","name":"gas","type":"uint256"},{"internalType":"uint256","name":"nonce","type":"uint256"},{"internalType":"bytes","name":"data","type":"bytes"}],"internalType":"struct FranklinForwarder.ForwardRequest","name":"req","type":"tuple"},{"internalType":"bytes","name":"signature","type":"bytes"}],"name":"execute","outputs":[{"internalType":"bool","name":"","type":"bool"},{"internalType":"bytes","name":"","type":"bytes"}],"stateMutability":"payable","type":"function"},{"inputs":[{"internalType":"address","name":"from","type":"address"}],"name":"getNonce","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"components":[{"internalType":"address","name":"from","type":"address"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"value","type":"uint256"},{"internalType":"uint256","name":"gas","type":"uint256"},{"internalType":"uint256","name":"nonce","type":"uint256"},{"internalType":"bytes","name":"data","type":"bytes"}],"internalType":"struct FranklinForwarder.ForwardRequest","name":"req","type":"tuple"},{"internalType":"bytes","name":"signature","type":"bytes"}],"name":"verify","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"}]