Contract Name:
GnosisSafeProxy
Contract Source Code:
File 1 of 1 : GnosisSafeProxy
/**
*Submitted for verification at Etherscan.io on 2021-07-09
*/
// SPDX-License-Identifier: LGPL-3.0-only
pragma solidity >=0.7.0 <0.9.0;
/// @title IProxy - Helper interface to access masterCopy of the Proxy on-chain
/// @author Richard Meissner - <richard@gnosis.io>
interface IProxy {
function masterCopy() external view returns (address);
}
/// @title GnosisSafeProxy - Generic proxy contract allows to execute all transactions applying the code of a master contract.
/// @author Stefan George - <stefan@gnosis.io>
/// @author Richard Meissner - <richard@gnosis.io>
contract GnosisSafeProxy {
// singleton always needs to be first declared variable, to ensure that it is at the same location in the contracts to which calls are delegated.
// To reduce deployment costs this variable is internal and needs to be retrieved via `getStorageAt`
address internal singleton;
/// @dev Constructor function sets address of singleton contract.
/// @param _singleton Singleton address.
constructor(address _singleton) {
require(_singleton != address(0), "Invalid singleton address provided");
singleton = _singleton;
}
/// @dev Fallback function forwards all transactions and returns all received return data.
fallback() external payable {
// solhint-disable-next-line no-inline-assembly
assembly {
let _singleton := and(sload(0), 0xffffffffffffffffffffffffffffffffffffffff)
// 0xa619486e == keccak("masterCopy()"). The value is right padded to 32-bytes with 0s
if eq(calldataload(0), 0xa619486e00000000000000000000000000000000000000000000000000000000) {
mstore(0, _singleton)
return(0, 0x20)
}
calldatacopy(0, 0, calldatasize())
let success := delegatecall(gas(), _singleton, 0, calldatasize(), 0, 0)
returndatacopy(0, 0, returndatasize())
if eq(success, 0) {
revert(0, returndatasize())
}
return(0, returndatasize())
}
}
}
/// @title Proxy Factory - Allows to create new proxy contact and execute a message call to the new proxy within one transaction.
/// @author Stefan George - <stefan@gnosis.pm>
contract GnosisSafeProxyFactory {
event ProxyCreation(GnosisSafeProxy proxy, address singleton);
/// @dev Allows to create new proxy contact and execute a message call to the new proxy within one transaction.
/// @param singleton Address of singleton contract.
/// @param data Payload for message call sent to new proxy contract.
function createProxy(address singleton, bytes memory data) public returns (GnosisSafeProxy proxy) {
proxy = new GnosisSafeProxy(singleton);
if (data.length > 0)
// solhint-disable-next-line no-inline-assembly
assembly {
if eq(call(gas(), proxy, 0, add(data, 0x20), mload(data), 0, 0), 0) {
revert(0, 0)
}
}
emit ProxyCreation(proxy, singleton);
}
/// @dev Allows to retrieve the runtime code of a deployed Proxy. This can be used to check that the expected Proxy was deployed.
function proxyRuntimeCode() public pure returns (bytes memory) {
return type(GnosisSafeProxy).runtimeCode;
}
/// @dev Allows to retrieve the creation code used for the Proxy deployment. With this it is easily possible to calculate predicted address.
function proxyCreationCode() public pure returns (bytes memory) {
return type(GnosisSafeProxy).creationCode;
}
/// @dev Allows to create new proxy contact using CREATE2 but it doesn't run the initializer.
/// This method is only meant as an utility to be called from other methods
/// @param _singleton Address of singleton contract.
/// @param initializer Payload for message call sent to new proxy contract.
/// @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
function deployProxyWithNonce(
address _singleton,
bytes memory initializer,
uint256 saltNonce
) internal returns (GnosisSafeProxy proxy) {
// If the initializer changes the proxy address should change too. Hashing the initializer data is cheaper than just concatinating it
bytes32 salt = keccak256(abi.encodePacked(keccak256(initializer), saltNonce));
bytes memory deploymentData = abi.encodePacked(type(GnosisSafeProxy).creationCode, uint256(uint160(_singleton)));
// solhint-disable-next-line no-inline-assembly
assembly {
proxy := create2(0x0, add(0x20, deploymentData), mload(deploymentData), salt)
}
require(address(proxy) != address(0), "Create2 call failed");
}
/// @dev Allows to create new proxy contact and execute a message call to the new proxy within one transaction.
/// @param _singleton Address of singleton contract.
/// @param initializer Payload for message call sent to new proxy contract.
/// @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
function createProxyWithNonce(
address _singleton,
bytes memory initializer,
uint256 saltNonce
) public returns (GnosisSafeProxy proxy) {
proxy = deployProxyWithNonce(_singleton, initializer, saltNonce);
if (initializer.length > 0)
// solhint-disable-next-line no-inline-assembly
assembly {
if eq(call(gas(), proxy, 0, add(initializer, 0x20), mload(initializer), 0, 0), 0) {
revert(0, 0)
}
}
emit ProxyCreation(proxy, _singleton);
}
/// @dev Allows to create new proxy contact, execute a message call to the new proxy and call a specified callback within one transaction
/// @param _singleton Address of singleton contract.
/// @param initializer Payload for message call sent to new proxy contract.
/// @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
/// @param callback Callback that will be invoced after the new proxy contract has been successfully deployed and initialized.
function createProxyWithCallback(
address _singleton,
bytes memory initializer,
uint256 saltNonce,
IProxyCreationCallback callback
) public returns (GnosisSafeProxy proxy) {
uint256 saltNonceWithCallback = uint256(keccak256(abi.encodePacked(saltNonce, callback)));
proxy = createProxyWithNonce(_singleton, initializer, saltNonceWithCallback);
if (address(callback) != address(0)) callback.proxyCreated(proxy, _singleton, initializer, saltNonce);
}
/// @dev Allows to get the address for a new proxy contact created via `createProxyWithNonce`
/// This method is only meant for address calculation purpose when you use an initializer that would revert,
/// therefore the response is returned with a revert. When calling this method set `from` to the address of the proxy factory.
/// @param _singleton Address of singleton contract.
/// @param initializer Payload for message call sent to new proxy contract.
/// @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
function calculateCreateProxyWithNonceAddress(
address _singleton,
bytes calldata initializer,
uint256 saltNonce
) external returns (GnosisSafeProxy proxy) {
proxy = deployProxyWithNonce(_singleton, initializer, saltNonce);
revert(string(abi.encodePacked(proxy)));
}
}
interface IProxyCreationCallback {
function proxyCreated(
GnosisSafeProxy proxy,
address _singleton,
bytes calldata initializer,
uint256 saltNonce
) external;
}