smartbugs-curated/dataset/arithmetic/BECToken.sol

307 lines
9.0 KiB
Solidity

/*
* @source: https://smartcontractsecurity.github.io/SWC-registry/docs/SWC-101#bectokensol
* @author: -
* @vulnerable_at_lines: 264
*/
pragma solidity ^0.4.16;
/**
* @title SafeMath
* @dev Math operations with safety checks that throw on error
*/
library SafeMath {
function mul(uint256 a, uint256 b) internal constant returns (uint256) {
uint256 c = a * b;
require(a == 0 || c / a == b);
return c;
}
function div(uint256 a, uint256 b) internal constant returns (uint256) {
// require(b > 0); // Solidity automatically throws when dividing by 0
uint256 c = a / b;
// require(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
function sub(uint256 a, uint256 b) internal constant returns (uint256) {
require(b <= a);
return a - b;
}
function add(uint256 a, uint256 b) internal constant returns (uint256) {
uint256 c = a + b;
require(c >= a);
return c;
}
}
/**
* @title ERC20Basic
* @dev Simpler version of ERC20 interface
* @dev see https://github.com/ethereum/EIPs/issues/179
*/
contract ERC20Basic {
uint256 public totalSupply;
function balanceOf(address who) public constant returns (uint256);
function transfer(address to, uint256 value) public returns (bool);
event Transfer(address indexed from, address indexed to, uint256 value);
}
/**
* @title Basic token
* @dev Basic version of StandardToken, with no allowances.
*/
contract BasicToken is ERC20Basic {
using SafeMath for uint256;
mapping(address => uint256) balances;
/**
* @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, uint256 _value) public returns (bool) {
require(_to != address(0));
require(_value > 0 && _value <= balances[msg.sender]);
// SafeMath.sub will throw if there is not enough balance.
balances[msg.sender] = balances[msg.sender].sub(_value);
balances[_to] = balances[_to].add(_value);
Transfer(msg.sender, _to, _value);
return true;
}
/**
* @dev Gets the balance of the specified address.
* @param _owner The address to query the the balance of.
* @return An uint256 representing the amount owned by the passed address.
*/
function balanceOf(address _owner) public constant returns (uint256 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) public constant 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);
}
/**
* @title Standard ERC20 token
*
* @dev Implementation of the basic standard 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 ERC20, BasicToken {
mapping (address => mapping (address => uint256)) internal 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 uint256 the amount of tokens to be transferred
*/
function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
require(_to != address(0));
require(_value > 0 && _value <= balances[_from]);
require(_value <= allowed[_from][msg.sender]);
balances[_from] = balances[_from].sub(_value);
balances[_to] = balances[_to].add(_value);
allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value);
Transfer(_from, _to, _value);
return true;
}
/**
* @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
*
* 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
* @param _spender The address which will spend the funds.
* @param _value The amount of tokens to be spent.
*/
function approve(address _spender, uint256 _value) public returns (bool) {
allowed[msg.sender][_spender] = _value;
Approval(msg.sender, _spender, _value);
return true;
}
/**
* @dev Function to check the amount of tokens that 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 uint256 specifying the amount of tokens still available for the spender.
*/
function allowance(address _owner, address _spender) public constant returns (uint256 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;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev The Ownable constructor sets the original `owner` of the contract to the sender
* account.
*/
function Ownable() {
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) onlyOwner public {
require(newOwner != address(0));
OwnershipTransferred(owner, newOwner);
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 make a function callable only when the contract is not paused.
*/
modifier whenNotPaused() {
require(!paused);
_;
}
/**
* @dev Modifier to make a function callable only when the contract is paused.
*/
modifier whenPaused() {
require(paused);
_;
}
/**
* @dev called by the owner to pause, triggers stopped state
*/
function pause() onlyOwner whenNotPaused public {
paused = true;
Pause();
}
/**
* @dev called by the owner to unpause, returns to normal state
*/
function unpause() onlyOwner whenPaused public {
paused = false;
Unpause();
}
}
/**
* @title Pausable token
*
* @dev StandardToken modified with pausable transfers.
**/
contract PausableToken is StandardToken, Pausable {
function transfer(address _to, uint256 _value) public whenNotPaused returns (bool) {
return super.transfer(_to, _value);
}
function transferFrom(address _from, address _to, uint256 _value) public whenNotPaused returns (bool) {
return super.transferFrom(_from, _to, _value);
}
function approve(address _spender, uint256 _value) public whenNotPaused returns (bool) {
return super.approve(_spender, _value);
}
function batchTransfer(address[] _receivers, uint256 _value) public whenNotPaused returns (bool) {
uint cnt = _receivers.length;
// <yes> <report> ARITHMETIC
uint256 amount = uint256(cnt) * _value;
require(cnt > 0 && cnt <= 20);
require(_value > 0 && balances[msg.sender] >= amount);
balances[msg.sender] = balances[msg.sender].sub(amount);
for (uint i = 0; i < cnt; i++) {
balances[_receivers[i]] = balances[_receivers[i]].add(_value);
Transfer(msg.sender, _receivers[i], _value);
}
return true;
}
}
/**
* @title Bec Token
*
* @dev Implementation of Bec Token based on the basic standard token.
*/
contract BecToken is PausableToken {
/**
* Public variables of the token
* The following variables are OPTIONAL vanities. One does not have to include them.
* They allow one to customise the token contract & in no way influences the core functionality.
* Some wallets/interfaces might not even bother to look at this information.
*/
string public name = "BeautyChain";
string public symbol = "BEC";
string public version = '1.0.0';
uint8 public decimals = 18;
/**
* @dev Function to check the amount of tokens that an owner allowed to a spender.
*/
function BecToken() {
totalSupply = 7000000000 * (10**(uint256(decimals)));
balances[msg.sender] = totalSupply; // Give the creator all initial tokens
}
function () {
//if ether is sent to this address, send it back.
revert();
}
}