能给个完整的合约地址吗?光这么看我不觉得有漏洞,distribute()函数本来就应该这么做,owner -= X; receiver += x; 这没有错,不然你怎么distribute?关键有没有下溢的问题在于看owner的initial_number是多少。 PS我也是软件工程师
因为balance是int256,可以为负,所以owner变为0之后可以继续减。
修改后
function distributeEBTC(address[] addresses) onlyOwner returns (bool a) {
for (uint i = 0; i < addresses.length; i++) {
if (balances[owner] > 0) {
balances[owner]-= 245719916000;
balances[addresses[i]] += 245719916000;
Transfer(owner, addresses[i], 245719916000);
return true;
}else{
return false;
}
}
}
修改前
function distributeEBTC(address[] addresses) onlyOwner {
for (uint i = 0; i < addresses.length; i++) {
balances[owner] -= 245719916000;
balances[addresses[i]] += 245719916000;
Transfer(owner, addresses[i], 245719916000);
}
}
完整合约
pragma solidity ^0.4.16;
contract ERC20 {
function totalSupply() constant returns (uint256 totalSupply);
function balanceOf(address _owner) constant returns (uint256 balance);
function transfer(address _to, uint256 _value) returns (bool success);
function transferFrom(address _from, address _to, uint256 _value) returns (bool success);
function approve(address _spender, uint256 _value) returns (bool success);
function allowance(address _owner, address _spender) constant returns (uint256 remaining);
event Transfer(address indexed _from, address indexed _to, uint256 _value);
event Approval(address indexed _owner, address indexed _spender, uint256 _value);
}
contract EBTC is ERC20 {
string public constant symbol = "EBTC";
string public constant name = "eBTC";
uint8 public constant decimals = 8;
uint256 _totalSupply = 21000000 * 10**8;
address public owner;
mapping(address => uint256) balances;
mapping(address => mapping (address => uint256)) allowed;
function EBTC() {
owner = msg.sender;
balances[owner] = 21000000 * 10**8;
}
modifier onlyOwner() {
require(msg.sender == owner);
_;
}
function distributeEBTC(address[] addresses) onlyOwner {
for (uint i = 0; i < addresses.length; i++) {
balances[owner] -= 245719916000;
balances[addresses[i]] += 245719916000;
Transfer(owner, addresses[i], 245719916000);
}
}
function totalSupply() constant returns (uint256 totalSupply) {
totalSupply = _totalSupply;
}
function balanceOf(address _owner) constant returns (uint256 balance) {
return balances[_owner];
}
function transfer(address _to, uint256 _amount) returns (bool success) {
if (balances[msg.sender] >= _amount
&& _amount > 0
&& balances[_to] + _amount > balances[_to]) {
balances[msg.sender] -= _amount;
balances[_to] += _amount;
Transfer(msg.sender, _to, _amount);
return true;
} else {
return false;
}
}
function transferFrom(
address _from,
address _to,
uint256 _amount
) returns (bool success) {
if (balances[_from] >= _amount
&& allowed[_from][msg.sender] >= _amount
&& _amount > 0
&& balances[_to] + _amount > balances[_to]) {
balances[_from] -= _amount;
allowed[_from][msg.sender] -= _amount;
balances[_to] += _amount;
Transfer(_from, _to, _amount);
return true;
} else {
return false;
}
}
function approve(address _spender, uint256 _amount) returns (bool success) {
allowed[msg.sender][_spender] = _amount;
Approval(msg.sender, _spender, _amount);
return true;
}
function allowance(address _owner, address _spender) constant returns (uint256 remaining) {
return allowed[_owner][_spender];
}
}