// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;/**
* @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
* ====
*/functionisContract(address account) internalviewreturns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in// construction, since the code is only stored at the end of the// constructor execution.uint256 size;
assembly {
size :=extcodesize(account)
}
return size >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].
*/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 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._
*/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");
require(isContract(target), "Address: call to non-contract");
(bool success, bytesmemory 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._
*/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) {
require(isContract(target), "Address: static call to non-contract");
(bool success, bytesmemory 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._
*/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) {
require(isContract(target), "Address: delegate call to non-contract");
(bool success, bytesmemory 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._
*/functionverifyCallResult(bool success,
bytesmemory returndata,
stringmemory errorMessage
) internalpurereturns (bytesmemory) {
if (success) {
return returndata;
} else {
// 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 assemblyassembly {
let returndata_size :=mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
Contract Source Code
File 2 of 14: BasicIronSafe.sol
// SPDX-License-Identifier: MITpragmasolidity 0.8.2;import"../common/IFerrumDeployer.sol";
import"@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import"../common/SafeAmount.sol";
import"../common/signature/PublicMultiSigCheckable.sol";
/**
@notice Basic implementation of IronSafe
IronSafe is a multisig wallet with a veto functionality
*/contractBasicIronSafeisPublicMultiSigCheckable{
usingSafeERC20forIERC20;
stringconstantpublic NAME ="FERRUM_BASIC_IRON_SAFE";
stringconstantpublic VERSION ="000.001";
addressconstantpublic DEFAULT_QUORUM_ID =address(1);
bytes32public deploySalt; // To control the deployed addressmapping(address=>bool) public vetoRights;
uint256public vetoRightsLength;
boolprivate _locked;
modifierlocked() {
require(!_locked, "BIS: Locked");
_locked =true;
_;
_locked =false;
}
constructor () EIP712(NAME, VERSION) {
(uint256 minSignatures,
address[] memory addresses,
bytes32 _deploySalt) =abi.decode(IFerrumDeployer(msg.sender).initData(),
(uint256, address[], bytes32));
deploySalt = _deploySalt;
_initialize(DEFAULT_QUORUM_ID, 1, uint16(minSignatures), 0, addresses);
}
/**
@notice Allow the contract to receive ETH
*/receive() externalpayable{}
/**
@notice Override the initialize method to
*/functioninitialize(address/*quorumId*/,
uint64/*groupId*/,
uint16/*minSignatures*/,
uint8/*ownerGroupId*/,
address[] calldata/*addresses*/) publicpureoverride{
revert("BIS: not supported");
}
bytes32constantprivate SET_VETO =keccak256(
"SetVeto(address to,bytes32 salt,uint64 expiry)");
/**
@notice Sets the veto right
@param to The to
@param salt The salt
@param multiSignature The multiSignature
*/functionsetVeto(address to, bytes32 salt, uint64 expiry, bytesmemory multiSignature
) externalexpiryRange(expiry) {
require(!vetoRights[to], "BIS: already has veto");
require(quorumSubscriptions[to].id !=address(0), "BIS: Not a quorum subscriber");
bytes32 message =keccak256(
abi.encode(SET_VETO, to, salt, expiry));
verifyMsg(message, salt, multiSignature);
vetoRights[to] =true;
vetoRightsLength +=1;
}
bytes32constantprivate UNSET_VETO =keccak256(
"UnsetVeto(address to,bytes32 salt,uint64 expiry)");
/**
@notice Unset the veto right
@param to Who to set the veto to
@param salt The signature salt
@param expiry The signature expiry
@param multiSignature The multi signature
*/functionunsetVeto(address to, bytes32 salt, uint64 expiry, bytesmemory multiSignature
) externalexpiryRange(expiry) {
require(vetoRights[to], "BSI: has no veto");
bytes32 message =keccak256(
abi.encode(UNSET_VETO, to, salt, expiry));
verifyMsg(message, salt, multiSignature);
_unsetVeto(to);
}
bytes32constantprivate SEND_ETH_SIGNED_METHOD =keccak256(
"SendEthSignedMethod(address to,uint256 amount,bytes32 salt,uint64 expiry)");
/**
@notice Sent ETH
@param to The receiver
@param amount The amount
@param salt The signature salt
@param multiSignature The multi signature
*/functionsendEthSigned(address to, uint256 amount,
bytes32 salt, uint64 expiry, bytesmemory multiSignature)
externalexpiryRange(expiry) locked{
bytes32 message =keccak256(
abi.encode(SEND_ETH_SIGNED_METHOD, to, amount, salt, expiry));
verifyMsg(message, salt, multiSignature);
SafeAmount.safeTransferETH(to, amount);
}
bytes32constantprivate SEND_SIGNED_METHOD =keccak256(
"SendSignedMethod(address to,address token,uint256 amount,bytes32 salt,uint64 expiry)");
functionsendSigned(address to, address token, uint256 amount,
bytes32 salt, uint64 expiry, bytesmemory multiSignature
) externalexpiryRange(expiry) {
bytes32 message =keccak256(
abi.encode(SEND_SIGNED_METHOD, to, token, amount, salt, expiry));
verifyMsg(message, salt, multiSignature);
IERC20(token).safeTransfer(to, amount);
}
/**
@notice Removes an address from the quorum. Note the number of addresses
in the quorum cannot drop below minSignatures.
For owned quorums, only owning quorum can execute this action. For non-owned
only quorum itself.
Also removes veto right if _address is a veto holder.
@param _address The address to remove
@param salt The signature salt
@param expiry The expiry
@param multiSignature The multisig encoded signature
*/functioninternalRemoveFromQuorum(address _address,
bytes32 salt,
uint64 expiry,
bytesmemory multiSignature
) internalvirtualoverride{
super.internalRemoveFromQuorum(_address, salt, expiry, multiSignature);
if (vetoRights[_address]) {
_unsetVeto(_address);
}
}
/*
@notice Unset the veto right
@param to Who to set the veto to
@param salt The signature salt
@param expiry The signature expiry
@param multiSignature The multi signature
*/function_unsetVeto(address to
) internal{
vetoRightsLength -=1;
delete vetoRights[to];
}
functionverifyMsg(bytes32 message, bytes32 salt, bytesmemory multisig
) internal{
require(!usedHashes[salt], "MSC: Message already used");
bytes32 digest = _hashTypedDataV4(message);
(bool result, address[] memory signers) = tryVerifyDigestWithAddress(
digest,
1,
multisig);
require(result, "BIS: invalid signature");
usedHashes[salt] =true;
// ensure there is at least one vetoif (vetoRightsLength ==0) {
return;
}
for (uint i=0; i<signers.length; i++) {
if (vetoRights[signers[i]]) {
return;
}
}
require(vetoRightsLength ==0, "BIS: no veto signature");
}
/**
@notice Override to use the veto signatures
@param message The message to verify
@param salt The salt to be unique
@param expectedGroupId The expected group ID
@param multiSignature The signatures formatted as a multisig
*/functionverifyUniqueSalt(bytes32 message,
bytes32 salt,
uint64 expectedGroupId,
bytesmemory multiSignature
) internaloverride{
require(expectedGroupId ==0, "BIS: Unsupported group ID");
verifyMsg(message, salt, multiSignature);
}
functionverifyUniqueSaltWithQuorumId(bytes32 message,
address expectedQuorumId,
bytes32 salt,
uint64 expectedGroupId,
bytesmemory multiSignature
) internaloverride{
require(multiSignature.length!=0, "MSC: multiSignature required");
bytes32 digest = _hashTypedDataV4(message);
(bool result, address[] memory signers) = tryVerifyDigestWithAddress(digest, expectedGroupId, multiSignature);
require(result, "MSC: Invalid signature");
require(!usedHashes[salt], "MSC: Message already used");
require(
expectedQuorumId ==address(0) ||
quorumSubscriptions[signers[0]].id == expectedQuorumId, "MSC: wrong quorum");
usedHashes[salt] =true;
for (uint i=0; i<signers.length; i++) {
if (vetoRights[signers[i]]) {
return;
}
}
require(vetoRightsLength ==0, "BIS: no veto signature");
}
}
Contract Source Code
File 3 of 14: Context.sol
// SPDX-License-Identifier: MITpragmasolidity ^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;
}
}
Contract Source Code
File 4 of 14: ECDSA.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;/**
* @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.
*/libraryECDSA{
enumRecoverError {
NoError,
InvalidSignature,
InvalidSignatureLength,
InvalidSignatureS,
InvalidSignatureV
}
function_throwError(RecoverError error) privatepure{
if (error == RecoverError.NoError) {
return; // no error: do nothing
} elseif (error == RecoverError.InvalidSignature) {
revert("ECDSA: invalid signature");
} elseif (error == RecoverError.InvalidSignatureLength) {
revert("ECDSA: invalid signature length");
} elseif (error == RecoverError.InvalidSignatureS) {
revert("ECDSA: invalid signature 's' value");
} elseif (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._
*/functiontryRecover(bytes32 hash, bytesmemory signature) internalpurereturns (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.assembly {
r :=mload(add(signature, 0x20))
s :=mload(add(signature, 0x40))
v :=byte(0, mload(add(signature, 0x60)))
}
return tryRecover(hash, v, r, s);
} elseif (signature.length==64) {
bytes32 r;
bytes32 vs;
// ecrecover takes the signature parameters, and the only way to get them// currently is to use 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.
*/functionrecover(bytes32 hash, bytesmemory signature) internalpurereturns (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._
*/functiontryRecover(bytes32 hash,
bytes32 r,
bytes32 vs
) internalpurereturns (address, RecoverError) {
bytes32 s;
uint8 v;
assembly {
s :=and(vs, 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
v :=add(shr(255, vs), 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._
*/functionrecover(bytes32 hash,
bytes32 r,
bytes32 vs
) internalpurereturns (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._
*/functiontryRecover(bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internalpurereturns (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 addressaddress 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.
*/functionrecover(bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internalpurereturns (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}.
*/functiontoEthSignedMessageHash(bytes32 hash) internalpurereturns (bytes32) {
// 32 is the length in bytes of hash,// enforced by the type signature abovereturnkeccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
}
/**
* @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}.
*/functiontoTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internalpurereturns (bytes32) {
returnkeccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
}
}
Contract Source Code
File 5 of 14: IERC20.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/interfaceIERC20{
/**
* @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 `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/functiontransfer(address recipient, 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 `sender` to `recipient` 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(address sender,
address recipient,
uint256 amount
) externalreturns (bool);
/**
* @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);
}
// SPDX-License-Identifier: MITpragmasolidity 0.8.2;import"@openzeppelin/contracts/utils/cryptography/draft-EIP712.sol";
import"@openzeppelin/contracts/utils/cryptography/ECDSA.sol";
import"../WithAdmin.sol";
import"./MultiSigLib.sol";
/**
@notice
Base class for contracts handling multisig transactions
Rules:
- First set up the master governance quorum (groupId 1). onlyOwner
- Owner can remove public or custom quorums, but cannot remove governance
quorums.
- Once master governance is setup, governance can add / remove any quorums
- All actions can only be submitted to chain by admin or owner
*/abstractcontractMultiSigCheckableisWithAdmin, EIP712{
uint16publicconstant GOVERNANCE_GROUP_ID_MAX =256;
uint32constant WEEK =3600*24*7;
structQuorum {
address id;
uint64 groupId; // GroupId: 0 => General, 1 => Governance, >1 => Customuint16 minSignatures;
// If the quorum is owned, only owner can change its config.// Owner must be a governence q (id <256)uint8 ownerGroupId;
}
eventQuorumCreated(Quorum quorum);
eventQuorumUpdated(Quorum quorum);
eventAddedToQuorum(address quorumId, address subscriber);
eventRemovedFromQuorum(address quorumId, address subscriber);
mapping(bytes32=>bool) public usedHashes;
mapping(address=> Quorum) public quorumSubscriptions; // Repeating quorum defs to reduce readsmapping(address=> Quorum) public quorums;
mapping(address=>uint256) public quorumsSubscribers;
mapping(uint256=>bool) internal groupIds; // List of registered group IDsaddress[] public quorumList; // Only for transparency. Not used. To sanity check quorums offchainmodifiergovernanceGroupId(uint64 expectedGroupId) {
require(
expectedGroupId < GOVERNANCE_GROUP_ID_MAX,
"MSC: must be governance"
);
_;
}
modifierexpiryRange(uint64 expiry) {
require(block.timestamp< expiry, "CR: signature timed out");
require(expiry <block.timestamp+ WEEK, "CR: expiry too far");
_;
}
/**
@notice Force remove from quorum (if managed)
to allow last resort option in case a quorum
goes rogue. Overwrite if you don't need an admin control
No check on minSig so if the no of members drops below
minSig, the quorum becomes unusable.
@param _address The address to be removed from quorum
*/functionforceRemoveFromQuorum(address _address)
externalvirtualonlyAdmin{
Quorum memory q = quorumSubscriptions[_address];
require(q.id !=address(0), "MSC: subscription not found");
_removeFromQuorum(_address, q.id);
}
bytes32constant REMOVE_FROM_QUORUM_METHOD =keccak256("RemoveFromQuorum(address _address,bytes32 salt,uint64 expiry)");
/**
@notice Removes an address from the quorum. Note the number of addresses
in the quorum cannot drop below minSignatures.
For owned quorums, only owning quorum can execute this action. For non-owned
only quorum itself.
@param _address The address to remove
@param salt The signature salt
@param expiry The expiry
@param multiSignature The multisig encoded signature
*/functionremoveFromQuorum(address _address,
bytes32 salt,
uint64 expiry,
bytesmemory multiSignature
) externalvirtual{
internalRemoveFromQuorum(_address, salt, expiry, multiSignature);
}
bytes32constant ADD_TO_QUORUM_METHOD =keccak256(
"AddToQuorum(address _address,address quorumId,bytes32 salt,uint64 expiry)"
);
/**
@notice Adds an address to the quorum.
For owned quorums, only owning quorum can execute this action. For non-owned
only quorum itself.
@param _address The address to be added
@param quorumId The quorum ID
@param salt The signature salt
@param expiry The expiry
@param multiSignature The multisig encoded signature
*/functionaddToQuorum(address _address,
address quorumId,
bytes32 salt,
uint64 expiry,
bytesmemory multiSignature
) externalexpiryRange(expiry) {
require(quorumId !=address(0), "MSC: quorumId required");
require(_address !=address(0), "MSC: address required");
require(salt !=0, "MSC: salt required");
bytes32 message =keccak256(
abi.encode(ADD_TO_QUORUM_METHOD, _address, quorumId, salt, expiry)
);
Quorum memory q = quorums[quorumId];
require(q.id !=address(0), "MSC: quorum not found");
uint64 expectedGroupId = q.ownerGroupId !=0
? q.ownerGroupId
: q.groupId;
verifyUniqueSaltWithQuorumId(message,
q.ownerGroupId !=0 ? address(0) : q.id,
salt, expectedGroupId, multiSignature);
require(quorumSubscriptions[_address].id ==address(0), "MSC: user already in a quorum");
quorumSubscriptions[_address] = q;
quorumsSubscribers[q.id] +=1;
emit AddedToQuorum(quorumId, _address);
}
bytes32constant UPDATE_MIN_SIGNATURE_METHOD =keccak256(
"UpdateMinSignature(address quorumId,uint16 minSignature,bytes32 salt,uint64 expiry)"
);
/**
@notice Updates the min signature for a quorum.
For owned quorums, only owning quorum can execute this action. For non-owned
only quorum itself.
@param quorumId The quorum ID
@param minSignature The new minSignature
@param salt The signature salt
@param expiry The expiry
@param multiSignature The multisig encoded signature
*/functionupdateMinSignature(address quorumId,
uint16 minSignature,
bytes32 salt,
uint64 expiry,
bytesmemory multiSignature
) externalexpiryRange(expiry) {
require(quorumId !=address(0), "MSC: quorumId required");
require(minSignature >0, "MSC: minSignature required");
require(salt !=0, "MSC: salt required");
Quorum memory q = quorums[quorumId];
require(q.id !=address(0), "MSC: quorumId not found");
require(
quorumsSubscribers[q.id] >= minSignature,
"MSC: minSignature is too large"
);
bytes32 message =keccak256(
abi.encode(
UPDATE_MIN_SIGNATURE_METHOD,
quorumId,
minSignature,
salt,
expiry
)
);
uint64 expectedGroupId = q.ownerGroupId !=0
? q.ownerGroupId
: q.groupId;
verifyUniqueSaltWithQuorumId(message,
q.ownerGroupId !=0 ? address(0) : q.id,
salt, expectedGroupId, multiSignature);
quorums[quorumId].minSignatures = minSignature;
}
bytes32constant CANCEL_SALTED_SIGNATURE =keccak256("CancelSaltedSignature(bytes32 salt)");
/**
@notice Cancel a salted signature
Remove this method if public can create groupIds.
People can write bots to prevent a person to execute a signed message.
This is useful for cases that the signers have signed a message
and decide to change it.
They can cancel the salt first, then issue a new signed message.
@param salt The signature salt
@param expectedGroupId Expected group ID for the signature
@param multiSignature The multisig encoded signature
*/functioncancelSaltedSignature(bytes32 salt,
uint64 expectedGroupId,
bytesmemory multiSignature
) externalvirtual{
require(salt !=0, "MSC: salt required");
bytes32 message =keccak256(abi.encode(CANCEL_SALTED_SIGNATURE, salt));
require(
expectedGroupId !=0&& expectedGroupId <256,
"MSC: not governance groupId"
);
verifyUniqueSalt(message, salt, expectedGroupId, multiSignature);
}
/**
@notice Initialize a quorum
Override this to allow public creatig new quorums.
If you allow public creating quorums, you MUST NOT have
customized groupIds. Make sure groupId is created from
hash of a quorum and is not duplicate.
@param quorumId The unique quorumID
@param groupId The groupID, which can be shared by quorums (if managed)
@param minSignatures The minimum number of signatures for the quorum
@param ownerGroupId The owner group ID. Can modify this quorum (if managed)
@param addresses List of addresses in the quorum
*/functioninitialize(address quorumId,
uint64 groupId,
uint16 minSignatures,
uint8 ownerGroupId,
address[] calldata addresses
) publicvirtualonlyAdmin{
_initialize(quorumId, groupId, minSignatures, ownerGroupId, addresses);
}
/**
@notice Initializes a quorum
@param quorumId The quorum ID
@param groupId The group ID
@param minSignatures The min signatures
@param ownerGroupId The owner group ID
@param addresses The initial addresses in the quorum
*/function_initialize(address quorumId,
uint64 groupId,
uint16 minSignatures,
uint8 ownerGroupId,
address[] memory addresses
) internalvirtual{
require(quorumId !=address(0), "MSC: quorumId required");
require(addresses.length>0, "MSC: addresses required");
require(minSignatures !=0, "MSC: minSignatures required");
require(
minSignatures <= addresses.length,
"MSC: minSignatures too large"
);
require(quorums[quorumId].id ==address(0), "MSC: already initialized");
require(ownerGroupId ==0|| ownerGroupId != groupId, "MSC: self ownership not allowed");
if (groupId !=0) {
ensureUniqueGroupId(groupId);
}
Quorum memory q = Quorum({
id: quorumId,
groupId: groupId,
minSignatures: minSignatures,
ownerGroupId: ownerGroupId
});
quorums[quorumId] = q;
quorumList.push(quorumId);
for (uint256 i =0; i < addresses.length; i++) {
require(
quorumSubscriptions[addresses[i]].id ==address(0),
"MSC: only one quorum per subscriber"
);
quorumSubscriptions[addresses[i]] = q;
}
quorumsSubscribers[quorumId] = addresses.length;
emit QuorumCreated(q);
}
/**
@notice Ensures groupID is unique. Override this method if your business
logic requires special management of groupId and ownerGroupIds such that
duplicate groupIds are allowed.
@param groupId The groupId
*/functionensureUniqueGroupId(uint256 groupId
) internalvirtual{
require(groupId !=0, "MSC: groupId required");
require(!groupIds[groupId], "MSC: groupId is not unique");
groupIds[groupId] =true;
}
/**
@notice Removes an address from the quorum. Note the number of addresses
in the quorum cannot drop below minSignatures.
For owned quorums, only owning quorum can execute this action. For non-owned
only quorum itself.
@param _address The address to remove
@param salt The signature salt
@param expiry The expiry
@param multiSignature The multisig encoded signature
*/functioninternalRemoveFromQuorum(address _address,
bytes32 salt,
uint64 expiry,
bytesmemory multiSignature
) internalvirtualexpiryRange(expiry) {
require(_address !=address(0), "MSC: address required");
require(salt !=0, "MSC: salt required");
Quorum memory q = quorumSubscriptions[_address];
require(q.id !=address(0), "MSC: subscription not found");
bytes32 message =keccak256(
abi.encode(REMOVE_FROM_QUORUM_METHOD, _address, salt, expiry)
);
uint64 expectedGroupId = q.ownerGroupId !=0
? q.ownerGroupId
: q.groupId;
verifyUniqueSaltWithQuorumId(message,
q.ownerGroupId !=0 ? address(0) : q.id,
salt, expectedGroupId, multiSignature);
uint256 subs = quorumsSubscribers[q.id];
require(subs >= quorums[q.id].minSignatures +1, "MSC: quorum becomes ususable");
_removeFromQuorum(_address, q.id);
}
/**
@notice Remove an address from the quorum
@param _address the address
@param qId The quorum ID
*/function_removeFromQuorum(address _address, address qId) internal{
delete quorumSubscriptions[_address];
quorumsSubscribers[qId] = quorumsSubscribers[qId] -1;
emit RemovedFromQuorum(qId, _address);
}
/**
@notice Checking salt's uniqueness because same message can be signed with different people.
@param message The message to verify
@param salt The salt to be unique
@param expectedGroupId The expected group ID
@param multiSignature The signatures formatted as a multisig
*/functionverifyUniqueSalt(bytes32 message,
bytes32 salt,
uint64 expectedGroupId,
bytesmemory multiSignature
) internalvirtual{
require(multiSignature.length!=0, "MSC: multiSignature required");
(, bool result) = tryVerify(message, expectedGroupId, multiSignature);
require(result, "MSC: Invalid signature");
require(!usedHashes[salt], "MSC: Message already used");
usedHashes[salt] =true;
}
functionverifyUniqueSaltWithQuorumId(bytes32 message,
address expectedQuorumId,
bytes32 salt,
uint64 expectedGroupId,
bytesmemory multiSignature
) internalvirtual{
require(multiSignature.length!=0, "MSC: multiSignature required");
bytes32 digest = _hashTypedDataV4(message);
(bool result, address[] memory signers) = tryVerifyDigestWithAddress(digest, expectedGroupId, multiSignature);
require(result, "MSC: Invalid signature");
require(!usedHashes[salt], "MSC: Message already used");
require(
expectedQuorumId ==address(0) ||
quorumSubscriptions[signers[0]].id == expectedQuorumId, "MSC: wrong quorum");
usedHashes[salt] =true;
}
/**
@notice Verifies the a unique un-salted message
@param message The message hash
@param expectedGroupId The expected group ID
@param multiSignature The signatures formatted as a multisig
*/functionverifyUniqueMessageDigest(bytes32 message,
uint64 expectedGroupId,
bytesmemory multiSignature
) internal{
require(multiSignature.length!=0, "MSC: multiSignature required");
(bytes32 salt, bool result) = tryVerify(
message,
expectedGroupId,
multiSignature
);
require(result, "MSC: Invalid signature");
require(!usedHashes[salt], "MSC: Message digest already used");
usedHashes[salt] =true;
}
/**
@notice Tries to verify a digest message
@param digest The digest
@param expectedGroupId The expected group ID
@param multiSignature The signatures formatted as a multisig
@return result Identifies success or failure
*/functiontryVerifyDigest(bytes32 digest,
uint64 expectedGroupId,
bytesmemory multiSignature
) internalviewreturns (bool result) {
(result, ) = tryVerifyDigestWithAddress(
digest,
expectedGroupId,
multiSignature
);
}
/**
@notice Returns if the digest can be verified
@param digest The digest
@param expectedGroupId The expected group ID
@param multiSignature The signatures formatted as a multisig. Note that this
format requires signatures to be sorted in the order of signers (as bytes)
@return result Identifies success or failure
@return signers Lis of signers.
*/functiontryVerifyDigestWithAddress(bytes32 digest,
uint64 expectedGroupId,
bytesmemory multiSignature
) internalviewreturns (bool result, address[] memory signers) {
require(multiSignature.length!=0, "MSC: multiSignature required");
MultiSigLib.Sig[] memory signatures = MultiSigLib.parseSig(
multiSignature
);
require(signatures.length>0, "MSC: no zero len signatures");
signers =newaddress[](signatures.length);
address _signer = ECDSA.recover(
digest,
signatures[0].v,
signatures[0].r,
signatures[0].s
);
signers[0] = _signer;
address quorumId = quorumSubscriptions[_signer].id;
if (quorumId ==address(0)) {
return (false, newaddress[](0));
}
require(
expectedGroupId ==0|| quorumSubscriptions[_signer].groupId == expectedGroupId,
"MSC: invalid groupId for signer"
);
Quorum memory q = quorums[quorumId];
for (uint256 i =1; i < signatures.length; i++) {
_signer = ECDSA.recover(
digest,
signatures[i].v,
signatures[i].r,
signatures[i].s
);
quorumId = quorumSubscriptions[_signer].id;
if (quorumId ==address(0)) {
return (false, newaddress[](0));
}
require(
q.id == quorumId,
"MSC: all signers must be of same quorum"
);
require(
expectedGroupId ==0|| q.groupId == expectedGroupId,
"MSC: invalid groupId for signer"
);
signers[i] = _signer;
// This ensures there are no duplicate signersrequire(signers[i -1] < _signer, "MSC: Sigs not sorted");
}
require(
signatures.length>= q.minSignatures,
"MSC: not enough signatures"
);
return (true, signers);
}
/**
@notice Tries to verify a message hash
@dev example message;
bytes32 constant METHOD_SIG =
keccak256("WithdrawSigned(address token,address payee,uint256 amount,bytes32 salt)");
bytes32 message = keccak256(abi.encode(
METHOD_SIG,
token,
payee,
amount,
salt
@param message The message
@param expectedGroupId The expected group ID
@param multiSignature The signatures formatted as a multisig
*/functiontryVerify(bytes32 message,
uint64 expectedGroupId,
bytesmemory multiSignature
) internalviewreturns (bytes32 digest, bool result) {
digest = _hashTypedDataV4(message);
result = tryVerifyDigest(digest, expectedGroupId, multiSignature);
}
}
Contract Source Code
File 8 of 14: MultiSigLib.sol
// SPDX-License-Identifier: MITpragmasolidity 0.8.2;libraryMultiSigLib{
structSig { uint8 v; bytes32 r; bytes32 s; }
/**
* Signature is encoded as below:
* every two bytes32, is an (r, s) pair.
* last bytes32 is the v's array.
* If we have more than 32 sigs, more
* bytes at the end are dedicated to vs.
*/functionparseSig(bytesmemory multiSig)
internalpurereturns (Sig[] memory sigs) {
uint cnt = multiSig.length/32;
cnt = cnt *32*2/ (2*32+1);
uint vLen = (multiSig.length/32) - cnt;
require(cnt - (cnt /2*2) ==0, "MSL: Invalid sig size");
sigs =new Sig[](cnt /2);
uint rPtr =0x20;
uint sPtr =0x40;
uint vPtr = multiSig.length- (vLen *0x20) +1;
for (uint i=0; i<cnt /2; i++) {
bytes32 r;
bytes32 s;
uint8 v;
assembly {
r :=mload(add(multiSig, rPtr))
s :=mload(add(multiSig, sPtr))
v :=mload(add(multiSig, vPtr))
}
rPtr = rPtr +0x40;
sPtr = sPtr +0x40;
vPtr = vPtr +1;
sigs[i].v = v;
sigs[i].r = r;
sigs[i].s = s;
}
}
}
Contract Source Code
File 9 of 14: Ownable.sol
// SPDX-License-Identifier: MITpragmasolidity ^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() {
_setOwner(_msgSender());
}
/**
* @dev Returns the address of the current owner.
*/functionowner() publicviewvirtualreturns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/modifieronlyOwner() {
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.
*/functionrenounceOwnership() publicvirtualonlyOwner{
_setOwner(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");
_setOwner(newOwner);
}
function_setOwner(address newOwner) private{
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
Contract Source Code
File 10 of 14: PublicMultiSigCheckable.sol
// SPDX-License-Identifier: MITpragmasolidity 0.8.2;import"./MultiSigCheckable.sol";
/**
* @dev This removes adminOnly and other relevant methods from a multiSigCheckable.
*/abstractcontractPublicMultiSigCheckableisMultiSigCheckable{
/**
@notice Initialize a quorum
Override this to allow public creatig new quorums.
If you allow public creating quorums, you MUST NOT have
customized groupIds. Make sure groupId is created from
hash of a quorum and is not duplicate.
@param quorumId The unique quorumID
@param groupId The groupID, which can be shared by quorums (if managed)
@param minSignatures The minimum number of signatures for the quorum
@param ownerGroupId The owner group ID. Can modify this quorum (if managed)
@param addresses List of addresses in the quorum
*/functioninitialize(address quorumId,
uint64 groupId,
uint16 minSignatures,
uint8 ownerGroupId,
address[] calldata addresses
) publicoverridevirtual{
_initialize(quorumId, groupId, minSignatures, ownerGroupId, addresses);
}
/**
@notice Disable force removal
*/functionforceRemoveFromQuorum(address) externaloverridevirtual{
revert("PMSC: Not supported");
}
/**
@notice Disable cancellation
*/functioncancelSaltedSignature(bytes32,
uint64,
bytesmemory) externaloverridevirtual{
revert("PMSC: Not supported");
}
}
Contract Source Code
File 11 of 14: SafeAmount.sol
// SPDX-License-Identifier: MITpragmasolidity 0.8.2;import"@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
librarySafeAmount{
usingSafeERC20forIERC20;
/**
@notice transfer tokens from. Incorporate fee on transfer tokens
@param token The token
@param from From address
@param to To address
@param amount The amount
@return result The actual amount transferred
*/functionsafeTransferFrom(address token,
addressfrom,
address to,
uint256 amount) internalreturns (uint256 result) {
uint256 preBalance = IERC20(token).balanceOf(to);
IERC20(token).safeTransferFrom(from, to, amount);
uint256 postBalance = IERC20(token).balanceOf(to);
result = postBalance - preBalance;
require(result <= amount, "SA: actual amount larger than transfer amount");
}
/**
@notice Sends ETH
@param to The to address
@param value The amount
*/functionsafeTransferETH(address to, uint256 value) internal{
(bool success, ) = to.call{value: value}(newbytes(0));
require(success, 'TransferHelper::safeTransferETH: ETH transfer failed');
}
}
Contract Source Code
File 12 of 14: SafeERC20.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;import"../IERC20.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;
functionsafeTransfer(
IERC20 token,
address to,
uint256 value
) internal{
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
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));
}
functionsafeIncreaseAllowance(
IERC20 token,
address spender,
uint256 value
) internal{
uint256 newAllowance = token.allowance(address(this), spender) + value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
functionsafeDecreaseAllowance(
IERC20 token,
address spender,
uint256 value
) internal{
unchecked {
uint256 oldAllowance = token.allowance(address(this), spender);
require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
uint256 newAllowance = oldAllowance - value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
}
/**
* @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");
if (returndata.length>0) {
// Return data is optionalrequire(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
// SPDX-License-Identifier: MITpragmasolidity ^0.8.0;import"./ECDSA.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._
*/abstractcontractEIP712{
/* solhint-disable var-name-mixedcase */// Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to// invalidate the cached domain separator if the chain id changes.bytes32privateimmutable _CACHED_DOMAIN_SEPARATOR;
uint256privateimmutable _CACHED_CHAIN_ID;
bytes32privateimmutable _HASHED_NAME;
bytes32privateimmutable _HASHED_VERSION;
bytes32privateimmutable _TYPE_HASH;
/* 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].
*/constructor(stringmemory name, stringmemory version) {
bytes32 hashedName =keccak256(bytes(name));
bytes32 hashedVersion =keccak256(bytes(version));
bytes32 typeHash =keccak256(
"EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
);
_HASHED_NAME = hashedName;
_HASHED_VERSION = hashedVersion;
_CACHED_CHAIN_ID =block.chainid;
_CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator(typeHash, hashedName, hashedVersion);
_TYPE_HASH = typeHash;
}
/**
* @dev Returns the domain separator for the current chain.
*/function_domainSeparatorV4() internalviewreturns (bytes32) {
if (block.chainid== _CACHED_CHAIN_ID) {
return _CACHED_DOMAIN_SEPARATOR;
} else {
return _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION);
}
}
function_buildDomainSeparator(bytes32 typeHash,
bytes32 nameHash,
bytes32 versionHash
) privateviewreturns (bytes32) {
returnkeccak256(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) internalviewvirtualreturns (bytes32) {
return ECDSA.toTypedDataHash(_domainSeparatorV4(), structHash);
}
}