Contract Name:
OwnedUpgradeabilityProxy
Contract Source Code:
pragma solidity ^0.4.24;
library Address {
/**
* Returns whether the target address is a contract
* @dev This function will return false if invoked during the constructor of a contract,
* as the code is not actually created until after the constructor finishes.
* @param account address of the account to check
* @return whether the target address is a contract
*/
function isContract(address account) internal view returns (bool) {
uint256 size;
// XXX Currently there is no better way to check if there is a contract in an address
// than to check the size of the code at that address.
// See https://ethereum.stackexchange.com/a/14016/36603
// for more details about how this works.
// TODO Check this again before the Serenity release, because all addresses will be
// contracts then.
// solhint-disable-next-line no-inline-assembly
assembly { size := extcodesize(account) }
return size > 0;
}
}
pragma solidity ^0.4.24;
import './UpgradeabilityProxy.sol';
/**
* @title OwnedUpgradeabilityProxy
* @dev This contract combines an upgradeability proxy with basic authorization control functionalities
*/
contract OwnedUpgradeabilityProxy is UpgradeabilityProxy {
/**
* @dev Event to show ownership has been transferred
* @param previousOwner representing the address of the previous owner
* @param newOwner representing the address of the new owner
*/
event ProxyOwnershipTransferred(address previousOwner, address newOwner);
// Storage position of the owner of the contract
bytes32 private constant proxyOwnerPosition = keccak256("org.zeppelinos.proxy.owner");
/**
* @dev the constructor sets the original owner of the contract to the sender account.
*/
constructor() public {
setUpgradeabilityOwner(msg.sender);
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyProxyOwner() {
require(msg.sender == proxyOwner());
_;
}
/**
* @dev Tells the address of the owner
* @return the address of the owner
*/
function proxyOwner() public view returns (address owner) {
bytes32 position = proxyOwnerPosition;
assembly {
owner := sload(position)
}
}
/**
* @dev Sets the address of the owner
*/
function setUpgradeabilityOwner(address newProxyOwner) internal {
bytes32 position = proxyOwnerPosition;
assembly {
sstore(position, newProxyOwner)
}
}
/**
* @dev Allows the current owner to transfer control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function transferProxyOwnership(address newOwner) public onlyProxyOwner {
require(newOwner != address(0));
emit ProxyOwnershipTransferred(proxyOwner(), newOwner);
setUpgradeabilityOwner(newOwner);
}
/**
* @dev Allows the proxy owner to upgrade the current version of the proxy.
* @param implementation representing the address of the new implementation to be set.
*/
function upgradeTo(address implementation) public onlyProxyOwner {
_upgradeTo(implementation);
}
/**
* @dev Allows the proxy owner to upgrade the current version of the proxy and call the new implementation
* to initialize whatever is needed through a low level call.
* @param implementation representing the address of the new implementation to be set.
* @param data represents the msg.data to bet sent in the low level call. This parameter may include the function
* signature of the implementation to be called with the needed payload
*/
function upgradeToAndCall(address implementation, bytes data) payable public onlyProxyOwner {
upgradeTo(implementation);
require(implementation.delegatecall(data));
}
}
pragma solidity ^0.4.24;
/**
* @title Proxy
* @dev Gives the possibility to delegate any call to a foreign implementation.
*/
contract Proxy {
/**
* @dev Tells the address of the implementation where every call will be delegated.
* @return address of the implementation to which it will be delegated
*/
function implementation() public view returns (address);
/**
* @dev Fallback function allowing to perform a delegatecall to the given implementation.
* This function will return whatever the implementation call returns
*/
function () payable public {
address _impl = implementation();
require(_impl != address(0));
assembly {
let ptr := mload(0x40)
calldatacopy(ptr, 0, calldatasize)
let result := delegatecall(gas, _impl, ptr, calldatasize, 0, 0)
let size := returndatasize
returndatacopy(ptr, 0, size)
switch result
case 0 { revert(ptr, size) }
default { return(ptr, size) }
}
}
}
pragma solidity ^0.4.24;
import './Proxy.sol';
import './Address.sol';
/**
* @title UpgradeabilityProxy
* @dev This contract represents a proxy where the implementation address to which it will delegate can be upgraded
*/
contract UpgradeabilityProxy is Proxy {
/**
* @dev This event will be emitted every time the implementation gets upgraded
* @param implementation representing the address of the upgraded implementation
*/
event Upgraded(address indexed implementation);
// Storage position of the address of the current implementation
bytes32 private constant implementationPosition = keccak256("org.zeppelinos.proxy.implementation");
/**
* @dev Constructor function
*/
constructor() public {}
/**
* @dev Tells the address of the current implementation
* @return address of the current implementation
*/
function implementation() public view returns (address impl) {
bytes32 position = implementationPosition;
assembly {
impl := sload(position)
}
}
/**
* @dev Sets the address of the current implementation
* @param newImplementation address representing the new implementation to be set
*/
function setImplementation(address newImplementation) internal {
require(Address.isContract(newImplementation),"newImplementation is not a contractAddress");
bytes32 position = implementationPosition;
assembly {
sstore(position, newImplementation)
}
}
/**
* @dev Upgrades the implementation address
* @param newImplementation representing the address of the new implementation to be set
*/
function _upgradeTo(address newImplementation) internal {
address currentImplementation = implementation();
require(currentImplementation != newImplementation);
setImplementation(newImplementation);
emit Upgraded(newImplementation);
}
}