Create two contracts that each with different accounts.

Question

I'm a newbie in blockchain. I am trying to repeat DAO attack using two different contracts, in my case DAO and Hacker. I want the 2 contracts belongs to 2 separated account, so I can see that the ethereum goes from DAO contract holder to Hacker contract holder in Genache. However, I got stuck since I can only migrate my contract using the same account based on command truffle --migrate -reset

Here are the contracts for both DAO and Hacker:

pragma solidity ^0.4.24;

contract Dao {
    struct User {
        address addr;
        string name;
        uint balence;
        uint8 flag;
    }

    //Fetch User
    mapping(address=>User) users; // create HashArray<address,User>, which can be random access

    uint public userCount;

    constructor() public {
        //user = "hello"; just for testing
        //addUser("wei");
        //addUser("alex");
    }

    function addUser (address _addr, string _name, uint _balence, uint _flag) private {
        users[_addr] = User(_addr,_name,0,1);
        userCount++;
    }

    function addToBalence(string name) public payable{
        if(users[msg.sender].flag != 1) addUser(msg.sender,name,0,1);
        users[msg.sender].balence = users[msg.sender].balence + msg.value;
    }

    function showBalence(address) public returns (uint) {
        return users[msg.sender].balence;
    }

    function withdraw(uint amount) public payable{

        if(users[msg.sender].flag != 1) revert("user does not exist");
        else if (users[msg.sender].balence >= amount){
            msg.sender.call.value(amount)();
            users[msg.sender].balence -= amount;
        }
        else return false;
    }
    }
}

contract Hacker {
    // the address of the user, so the money can be transfered
    Dao dao;
    address userAddress;
    string userName;

    constructor(string name, address daoAddr) public {
        dao = Dao(daoAddr);
        userAddress = msg.sender;
        userName = name;
    }

    function payout(uint amount) public payable{
        dao.withdraw(amount);
    }
}

Answer 1

In your Truffle migration file, you are able to specify the from account which actually deploys the contract. Details are in their documentation here.

Assuming you are using a tool like Ganache for your local blockchain simulator, you should be provided with 10 accounts which you can access as shown below:

var MyContract1 = artifacts.require("MyContract1");
var MyContract2 = artifacts.require("MyContract2");

module.exports = function(deployer) {
  deployer.deploy(MyContract1, {from: web3.eth.accounts[0]});
  deployer.deploy(MyContract2, {from: web3.eth.accounts[1]});
};

Let me know if this helps.

Answer 2

I'll post the detail solution here, in case someone stumble on this. Note that all the credit goes to @Shawn Tabrizi

here is the structure of my project folder for both contract and migration

\contracts
 **MyContracts.sol**
\migrations
 1_initial_migration.js
 **2_deploy_contracts.js**

I have added *symple to the files written by me.

MyContracts.sol looks like this

pragma solidity ^0.4.24;
contract MyContract1 {...}
contract MyContract2 {...}

2_deploy_contracts.js looks like this

var MyContract1 = artifacts.require("MyContract1");
var MyContract1 = artifacts.require("MyContract2");
module.exports = function(deployer) {
deployer.deploy(MyContract1, {from: "0x2e...")); // copy paste from Genache GUI provided account
deployer.deploy(MyContract2, {from: "0xfa..."});// copy paste from Genache GUI provided account
};

As a result, I was able to migrate my contracts to local blockchain setup by Ganache and using truffle migrate --reset.