hello guys, I'm just playing with BEP20 tokens and found the code on github. I want my code to be secure but the original code is using uint (and not uint256) so I'm not sure if my edit is valid: I have added 3 lines to use safemath:
pragma solidity ^0.8.2;
import 'https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/math/SafeMath.sol';
contract Token {
using SafeMath for uint256;
using SafeMath for uint;
mapping(address => uint) public balances;
mapping(address => mapping(address => uint)) public allowance;
uint public totalSupply = 123 * 10 ** 18;
string public name = "My Token";
string public symbol = "TKN";
uint public decimals = 18;
event Transfer(address indexed from, address indexed to, uint value);
event Approval(address indexed owner, address indexed spender, uint value);
constructor() {
balances[msg.sender] = totalSupply;
}
function balanceOf(address owner) public returns(uint) {
return balances[owner];
}
function transfer(address to, uint value) public returns(bool) {
require(balanceOf(msg.sender) >= value, 'balance too low');
balances[to] += value;
balances[msg.sender] -= value;
emit Transfer(msg.sender, to, value);
return true;
}
function transferFrom(address from, address to, uint value) public returns(bool) {
require(balanceOf(from) >= value, 'balance too low');
require(allowance[from][msg.sender] >= value, 'allowance too low');
balances[to] += value;
balances[from] -= value;
emit Transfer(from, to, value);
return true;
}
function approve(address spender, uint value) public returns (bool) {
allowance[msg.sender][spender] = value;
emit Approval(msg.sender, spender, value);
return true;
}
}
my added lines:
import 'https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/math/SafeMath.sol';
using SafeMath for uint256;
using SafeMath for uint;
so just import safemath, and then use safemath for uint256 BUT ALSO use safemath for uint - is this like a valid implementation and is the token code now safe? it was without safemath and I didn't like it...
