Contract Source Code:
File 1 of 1 : CNYToken
pragma solidity ^0.4.23;
/**
* Math operations with safety checks
*/
library SafeMath {
/**
* @dev Multiplies two numbers, revert()s on overflow.
*/
function mul(uint256 a, uint256 b) internal returns (uint256 c) {
if (a == 0) {
return 0;
}
c = a * b;
assert(c / a == b);
return c;
}
/**
* @dev Integer division of two numbers, truncating the quotient.
*/
function div(uint256 a, uint256 b) internal returns (uint256) {
// assert(b > 0); // Solidity automatically revert()s when dividing by 0
// uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return a / b;
}
/**
* @dev Subtracts two numbers, revert()s on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 a, uint256 b) internal returns (uint256) {
assert(b <= a);
return a - b;
}
/**
* @dev Adds two numbers, revert()s on overflow.
*/
function add(uint256 a, uint256 b) internal returns (uint256 c) {
c = a + b;
assert(c >= a && c >= b);
return c;
}
function assert(bool assertion) internal {
if (!assertion) {
revert();
}
}
}
/**
* @title ERC20Basic
* @dev Simpler version of ERC20 interface
* @dev see https://github.com/ethereum/EIPs/issues/20
*/
contract ERC20Basic {
function balanceOf(address who) constant returns (uint);
function transfer(address to, uint value);
event Transfer(address indexed from, address indexed to, uint value);
}
/**
* @title Basic token
* @dev Basic version of StandardToken, with no allowances.
*/
contract BasicToken is ERC20Basic {
using SafeMath for uint;
mapping(address => uint) balances;
/**
* @dev Fix for the ERC20 short address attack.
*/
modifier onlyPayloadSize(uint size) {
if(msg.data.length < size.add(4)) {
revert();
}
_;
}
/**
* @dev transfer token for a specified address
* @param _to The address to transfer to.
* @param _value The amount to be transferred.
*/
function transfer(address _to, uint _value) onlyPayloadSize(2 * 32) {
require(_to != 0x0);
balances[msg.sender] = balances[msg.sender].sub(_value);
balances[_to] = balances[_to].add(_value);
emit Transfer(msg.sender, _to, _value);
}
/**
* @dev Gets the balance of the specified address.
* @param _owner The address to query the the balance of.
* @return An uint representing the amount owned by the passed address.
*/
function balanceOf(address _owner) constant returns (uint balance) {
return balances[_owner];
}
}
/**
* @title ERC20 interface
* @dev see https://github.com/ethereum/EIPs/issues/20
*/
contract ERC20 is ERC20Basic {
function allowance(address owner, address spender) constant returns (uint);
function transferFrom(address from, address to, uint value);
function approve(address spender, uint value);
event Approval(address indexed owner, address indexed spender, uint value);
}
/**
* @title Standard ERC20 token
*
* @dev Implemantation of the basic standart token.
* @dev https://github.com/ethereum/EIPs/issues/20
* @dev Based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
*/
contract StandardToken is BasicToken, ERC20 {
mapping (address => mapping (address => uint)) allowed;
/**
* @dev Transfer tokens from one address to another
* @param _from address The address which you want to send tokens from
* @param _to address The address which you want to transfer to
* @param _value uint the amout of tokens to be transfered
*/
function transferFrom(address _from, address _to, uint _value) onlyPayloadSize(3 * 32) {
require(_to != 0x0);
uint _allowance = allowed[_from][msg.sender];
// Check is not needed because sub(_allowance, _value) will already revert() if this condition is not met
// if (_value > _allowance) revert();
balances[_to] = balances[_to].add(_value);
balances[_from] = balances[_from].sub(_value);
allowed[_from][msg.sender] = _allowance.sub(_value);
emit Transfer(_from, _to, _value);
}
/**
* @dev Aprove the passed address to spend the specified amount of tokens on beahlf of msg.sender.
* @param _spender The address which will spend the funds.
* @param _value The amount of tokens to be spent.
*/
function approve(address _spender, uint _value) {
// To change the approve amount you first have to reduce the addresses`
// allowance to zero by calling `approve(_spender, 0)` if it is not
// already 0 to mitigate the race condition described here:
// https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
if ((_value != 0) && (allowed[msg.sender][_spender] != 0)) revert();
allowed[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
}
/**
* @dev Function to check the amount of tokens than an owner allowed to a spender.
* @param _owner address The address which owns the funds.
* @param _spender address The address which will spend the funds.
* @return A uint specifing the amount of tokens still avaible for the spender.
*/
function allowance(address _owner, address _spender) constant returns (uint remaining) {
return allowed[_owner][_spender];
}
}
/**
* @title Ownable
* @dev The Ownable contract has an owner address, and provides basic authorization control
* functions, this simplifies the implementation of "user permissions".
*/
contract Ownable {
address public owner;
/**
* @dev The Ownable constructor sets the original `owner` of the contract to the sender
* account.
*/
function Ownable() {
owner = msg.sender;
}
/**
* @dev revert()s if called by any account other than the owner.
*/
modifier onlyOwner() {
if (msg.sender != owner) {
revert();
}
_;
}
/**
* @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) onlyOwner {
if (newOwner != address(0)) {
owner = newOwner;
}
}
}
/**
* @title Pausable
* @dev Base contract which allows children to implement an emergency stop mechanism.
*/
contract Pausable is Ownable {
event Pause();
event Unpause();
bool public paused = false;
/**
* @dev modifier to allow actions only when the contract IS paused
*/
modifier whenNotPaused() {
if (paused) revert();
_;
}
/**
* @dev modifier to allow actions only when the contract IS NOT paused
*/
modifier whenPaused {
if (!paused) revert();
_;
}
/**
* @dev called by the owner to pause, triggers stopped state
*/
function pause() onlyOwner whenNotPaused returns (bool) {
paused = true;
emit Pause();
return true;
}
/**
* @dev called by the owner to unpause, returns to normal state
*/
function unpause() onlyOwner whenPaused returns (bool) {
paused = false;
emit Unpause();
return true;
}
}
/**
* Pausable token
*
* Simple ERC20 Token example, with pausable token creation
**/
contract PausableToken is StandardToken, Pausable {
function transfer(address _to, uint _value) whenNotPaused {
super.transfer(_to, _value);
}
function transferFrom(address _from, address _to, uint _value) whenNotPaused {
super.transferFrom(_from, _to, _value);
}
}
/**
* @title CNYToken
* @dev CNY Token contract
*/
contract CNYToken is PausableToken {
using SafeMath for uint256;
function () {
//if ether is sent to this address, send it back.
revert();
}
string public name = "CNYToken";
string public symbol = "CNYt";
uint8 public decimals = 18;
uint public totalSupply = 100000000000000000000000000;
string public version = 'CNYt 2.0';
// The nonce for avoid transfer replay attacks
mapping(address => uint256) nonces;
event Burn(address indexed burner, uint256 value);
function CNYToken() {
balances[msg.sender] = totalSupply; // Give the creator all initial tokens
}
/**
* @dev Burns a specific amount of tokens.
* @param _value The amount of token to be burned.
*/
function burn(uint256 _value) onlyOwner whenNotPaused {
_burn(msg.sender, _value);
}
function _burn(address _who, uint256 _value) internal {
require(_value <= balances[_who]);
// no need to require value <= totalSupply, since that would imply the
// sender's balance is greater than the totalSupply, which *should* be an assertion failure
balances[_who] = balances[_who].sub(_value);
totalSupply = totalSupply.sub(_value);
emit Burn(_who, _value);
emit Transfer(_who, address(0), _value);
}
/*
* Proxy transfer HC token. When some users of the ethereum account don't have ether,
* Who can authorize the agent for broadcast transactions, the agents may charge fees
* @param _from
* @param _to
* @param _value
* @param fee
* @param _v
* @param _r
* @param _s
* @param _comment
*/
function transferProxy(address _from, address _to, uint256 _value, uint256 _fee,
uint8 _v, bytes32 _r, bytes32 _s) whenNotPaused {
require((balances[_from] >= _fee.add(_value)));
require(balances[_to].add(_value) >= balances[_to]);
require(balances[msg.sender].add(_fee) >= balances[msg.sender]);
uint256 nonce = nonces[_from];
bytes32 hash = keccak256(_from,_to,_value,_fee,nonce);
bytes memory prefix = "\x19Ethereum Signed Message:\n32";
bytes32 prefixedHash = keccak256(prefix, hash);
require(_from == ecrecover(prefixedHash,_v,_r,_s));
balances[_from] = balances[_from].sub(_value.add(_fee));
balances[_to] = balances[_to].add(_value);
balances[msg.sender] = balances[msg.sender].add(_fee);
nonces[_from] = nonce.add(1);
emit Transfer(_from, _to, _value);
emit Transfer(_from, msg.sender, _fee);
}
// Allocate tokens to the users
// @param _to The owner of the token
// @param _value The value of the token
function allocateTokens(address _to, uint256 _value) onlyOwner {
require(totalSupply.add(_value) > totalSupply);
require(balances[_to].add(_value) > balances[_to]);
totalSupply = totalSupply.add(_value);
balances[_to] = balances[_to].add(_value);
emit Transfer(msg.sender, _to, _value);
}
}