/**
*Submitted for verification at Etherscan.io on 2018-06-12
*/
pragma solidity ^0.4.13;
contract Ownable {
address public owner;
event OwnershipRenounced(address indexed previousOwner);
event OwnershipTransferred(
address indexed previousOwner,
address indexed newOwner
);
/**
* @dev The Ownable constructor sets the original `owner` of the contract to the sender
* account.
*/
constructor() public {
owner = msg.sender;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(msg.sender == owner);
_;
}
/**
* @dev Allows the current owner to transfer control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function transferOwnership(address newOwner) public onlyOwner {
require(newOwner != address(0));
emit OwnershipTransferred(owner, newOwner);
owner = newOwner;
}
/**
* @dev Allows the current owner to relinquish control of the contract.
*/
function renounceOwnership() public onlyOwner {
emit OwnershipRenounced(owner);
owner = address(0);
}
}
contract ERC20Basic {
function totalSupply() public view returns (uint256);
function balanceOf(address who) public view returns (uint256);
function transfer(address to, uint256 value) public returns (bool);
event Transfer(address indexed from, address indexed to, uint256 value);
}
contract ERC20 is ERC20Basic {
function allowance(address owner, address spender)
public view returns (uint256);
function transferFrom(address from, address to, uint256 value)
public returns (bool);
function approve(address spender, uint256 value) public returns (bool);
event Approval(
address indexed owner,
address indexed spender,
uint256 value
);
}
contract TokenRecipient {
event ReceivedEther(address indexed sender, uint amount);
event ReceivedTokens(address indexed from, uint256 value, address indexed token, bytes extraData);
/**
* @dev Receive tokens and generate a log event
* @param from Address from which to transfer tokens
* @param value Amount of tokens to transfer
* @param token Address of token
* @param extraData Additional data to log
*/
function receiveApproval(address from, uint256 value, address token, bytes extraData) public {
ERC20 t = ERC20(token);
require(t.transferFrom(from, this, value));
emit ReceivedTokens(from, value, token, extraData);
}
/**
* @dev Receive Ether and generate a log event
*/
function () payable public {
emit ReceivedEther(msg.sender, msg.value);
}
}
contract ProxyRegistry is Ownable {
/* DelegateProxy implementation contract. Must be initialized. */
address public delegateProxyImplementation;
/* Authenticated proxies by user. */
mapping(address => OwnableDelegateProxy) public proxies;
/* Contracts pending access. */
mapping(address => uint) public pending;
/* Contracts allowed to call those proxies. */
mapping(address => bool) public contracts;
/* Delay period for adding an authenticated contract.
This mitigates a particular class of potential attack on the Wyvern DAO (which owns this registry) - if at any point the value of assets held by proxy contracts exceeded the value of half the WYV supply (votes in the DAO),
a malicious but rational attacker could buy half the Wyvern and grant themselves access to all the proxy contracts. A delay period renders this attack nonthreatening - given two weeks, if that happened, users would have
plenty of time to notice and transfer their assets.
*/
uint public DELAY_PERIOD = 2 weeks;
/**
* Start the process to enable access for specified contract. Subject to delay period.
*
* @dev ProxyRegistry owner only
* @param addr Address to which to grant permissions
*/
function startGrantAuthentication (address addr)
public
onlyOwner
{
require(!contracts[addr] && pending[addr] == 0);
pending[addr] = now;
}
/**
* End the process to nable access for specified contract after delay period has passed.
*
* @dev ProxyRegistry owner only
* @param addr Address to which to grant permissions
*/
function endGrantAuthentication (address addr)
public
onlyOwner
{
require(!contracts[addr] && pending[addr] != 0 && ((pending[addr] + DELAY_PERIOD) < now));
pending[addr] = 0;
contracts[addr] = true;
}
/**
* Revoke access for specified contract. Can be done instantly.
*
* @dev ProxyRegistry owner only
* @param addr Address of which to revoke permissions
*/
function revokeAuthentication (address addr)
public
onlyOwner
{
contracts[addr] = false;
}
/**
* Register a proxy contract with this registry
*
* @dev Must be called by the user which the proxy is for, creates a new AuthenticatedProxy
* @return New AuthenticatedProxy contract
*/
function registerProxy()
public
returns (OwnableDelegateProxy proxy)
{
require(proxies[msg.sender] == address(0));
proxy = new OwnableDelegateProxy(msg.sender, delegateProxyImplementation, abi.encodeWithSignature("initialize(address,address)", msg.sender, address(this)));
proxies[msg.sender] = proxy;
return proxy;
}
}
contract TokenTransferProxy {
/* Authentication registry. */
ProxyRegistry public registry;
/**
* Call ERC20 `transferFrom`
*
* @dev Authenticated contract only
* @param token ERC20 token address
* @param from From address
* @param to To address
* @param amount Transfer amount
*/
function transferFrom(address token, address from, address to, uint amount)
public
returns (bool)
{
require(registry.contracts(msg.sender));
return ERC20(token).transferFrom(from, to, amount);
}
}
contract WyvernTokenTransferProxy is TokenTransferProxy {
constructor (ProxyRegistry registryAddr)
public
{
registry = registryAddr;
}
}
contract OwnedUpgradeabilityStorage {
// Current implementation
address internal _implementation;
// Owner of the contract
address private _upgradeabilityOwner;
/**
* @dev Tells the address of the owner
* @return the address of the owner
*/
function upgradeabilityOwner() public view returns (address) {
return _upgradeabilityOwner;
}
/**
* @dev Sets the address of the owner
*/
function setUpgradeabilityOwner(address newUpgradeabilityOwner) internal {
_upgradeabilityOwner = newUpgradeabilityOwner;
}
/**
* @dev Tells the address of the current implementation
* @return address of the current implementation
*/
function implementation() public view returns (address) {
return _implementation;
}
/**
* @dev Tells the proxy type (EIP 897)
* @return Proxy type, 2 for forwarding proxy
*/
function proxyType() public pure returns (uint256 proxyTypeId) {
return 2;
}
}
contract AuthenticatedProxy is TokenRecipient, OwnedUpgradeabilityStorage {
/* Whether initialized. */
bool initialized = false;
/* Address which owns this proxy. */
address public user;
/* Associated registry with contract authentication information. */
ProxyRegistry public registry;
/* Whether access has been revoked. */
bool public revoked;
/* Delegate call could be used to atomically transfer multiple assets owned by the proxy contract with one order. */
enum HowToCall { Call, DelegateCall }
/* Event fired when the proxy access is revoked or unrevoked. */
event Revoked(bool revoked);
/**
* Initialize an AuthenticatedProxy
*
* @param addrUser Address of user on whose behalf this proxy will act
* @param addrRegistry Address of ProxyRegistry contract which will manage this proxy
*/
function initialize (address addrUser, ProxyRegistry addrRegistry)
public
{
require(!initialized);
initialized = true;
user = addrUser;
registry = addrRegistry;
}
/**
* Set the revoked flag (allows a user to revoke ProxyRegistry access)
*
* @dev Can be called by the user only
* @param revoke Whether or not to revoke access
*/
function setRevoke(bool revoke)
public
{
require(msg.sender == user);
revoked = revoke;
emit Revoked(revoke);
}
/**
* Execute a message call from the proxy contract
*
* @dev Can be called by the user, or by a contract authorized by the registry as long as the user has not revoked access
* @param dest Address to which the call will be sent
* @param howToCall Which kind of call to make
* @param calldata Calldata to send
* @return Result of the call (success or failure)
*/
function proxy(address dest, HowToCall howToCall, bytes calldata)
public
returns (bool result)
{
require(msg.sender == user || (!revoked && registry.contracts(msg.sender)));
if (howToCall == HowToCall.Call) {
result = dest.call(calldata);
} else if (howToCall == HowToCall.DelegateCall) {
result = dest.delegatecall(calldata);
}
return result;
}
/**
* Execute a message call and assert success
*
* @dev Same functionality as `proxy`, just asserts the return value
* @param dest Address to which the call will be sent
* @param howToCall What kind of call to make
* @param calldata Calldata to send
*/
function proxyAssert(address dest, HowToCall howToCall, bytes calldata)
public
{
require(proxy(dest, howToCall, calldata));
}
}
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 Tells the type of proxy (EIP 897)
* @return Type of proxy, 2 for upgradeable proxy
*/
function proxyType() public pure returns (uint256 proxyTypeId);
/**
* @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) }
}
}
}
contract OwnedUpgradeabilityProxy is Proxy, OwnedUpgradeabilityStorage {
/**
* @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);
/**
* @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);
/**
* @dev Upgrades the implementation address
* @param implementation representing the address of the new implementation to be set
*/
function _upgradeTo(address implementation) internal {
require(_implementation != implementation);
_implementation = implementation;
emit Upgraded(implementation);
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyProxyOwner() {
require(msg.sender == proxyOwner());
_;
}
/**
* @dev Tells the address of the proxy owner
* @return the address of the proxy owner
*/
function proxyOwner() public view returns (address) {
return upgradeabilityOwner();
}
/**
* @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 upgradeability owner to upgrade the current implementation 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 upgradeability owner to upgrade the current implementation of the proxy
* and delegatecall the new implementation for initialization.
* @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(address(this).delegatecall(data));
}
}
contract OwnableDelegateProxy is OwnedUpgradeabilityProxy {
constructor(address owner, address initialImplementation, bytes calldata)
public
{
setUpgradeabilityOwner(owner);
_upgradeTo(initialImplementation);
require(initialImplementation.delegatecall(calldata));
}
}
{
"compilationTarget": {
"WyvernTokenTransferProxy.sol": "WyvernTokenTransferProxy"
},
"evmVersion": "byzantium",
"libraries": {},
"optimizer": {
"enabled": false,
"runs": 200
},
"remappings": []
}
[{"constant":false,"inputs":[{"name":"token","type":"address"},{"name":"from","type":"address"},{"name":"to","type":"address"},{"name":"amount","type":"uint256"}],"name":"transferFrom","outputs":[{"name":"","type":"bool"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[],"name":"registry","outputs":[{"name":"","type":"address"}],"payable":false,"stateMutability":"view","type":"function"},{"inputs":[{"name":"registryAddr","type":"address"}],"payable":false,"stateMutability":"nonpayable","type":"constructor"}]