For Loop help In a Hash Cracker Homework.
- by aaron burns
On the homework I am working on we are making a hash cracker. I am implementing it so as to have my cracker. java call worker.java. Worker.java implements Runnable. Worker is to take the start and end of a list of char, the hash it is to crack, and the max length of the password that made the hash. I know I want to do a loop in run() BUT I cannot think of how I would do it so it would go to the given max pasword length. I have posted the code I have so far. Any directions or areas I should look into.... I thought there was a way to do this with a certain way to write the loop but I don't know or can't find the correct syntax.
Oh.. also. In main I divide up so x amount of threads can be chosen and I know that as of write now it only works for an even number of the 40 possible char given.
package HashCracker;
import java.util.*;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
public class Cracker {
// Array of chars used to produce strings
public static final char[] CHARS = "abcdefghijklmnopqrstuvwxyz0123456789.,-!".toCharArray();
public static final int numOfChar=40;
/*
Given a byte[] array, produces a hex String,
such as "234a6f". with 2 chars for each byte in the array.
(provided code)
*/
public static String hexToString(byte[] bytes) {
StringBuffer buff = new StringBuffer();
for (int i=0; i<bytes.length; i++) {
int val = bytes[i];
val = val & 0xff; // remove higher bits, sign
if (val<16) buff.append('0'); // leading 0
buff.append(Integer.toString(val, 16));
}
return buff.toString();
}
/*
Given a string of hex byte values such as "24a26f", creates
a byte[] array of those values, one byte value -128..127
for each 2 chars.
(provided code)
*/
public static byte[] hexToArray(String hex) {
byte[] result = new byte[hex.length()/2];
for (int i=0; i<hex.length(); i+=2) {
result[i/2] = (byte) Integer.parseInt(hex.substring(i, i+2), 16);
}
return result;
}
public static void main(String args[]) throws NoSuchAlgorithmException
{
if(args.length==1)//Hash Maker
{
//create a byte array , meassage digestand put password into it
//and get out a hash value printed to the screen using provided methods.
byte[] myByteArray=args[0].getBytes();
MessageDigest hasher=MessageDigest.getInstance("SHA-1");
hasher.update(myByteArray);
byte[] digestedByte=hasher.digest();
String hashValue=Cracker.hexToString(digestedByte);
System.out.println(hashValue);
}
else//Hash Cracker
{
ArrayList<Thread> myRunnables=new ArrayList<Thread>();
int numOfThreads = Integer.parseInt(args[2]);
int charPerThread=Cracker.numOfChar/numOfThreads;
int start=0;
int end=charPerThread-1;
for(int i=0; i<numOfThreads; i++)
{
//creates, stores and starts threads.
Runnable tempWorker=new Worker(start, end, args[1], Integer.parseInt(args[1]));
Thread temp=new Thread(tempWorker);
myRunnables.add(temp);
temp.start();
start=end+1;
end=end+charPerThread;
}
}
}
import java.util.*;
public class Worker implements Runnable{
private int charStart;
private int charEnd;
private String Hash2Crack;
private int maxLength;
public Worker(int start, int end, String hashValue, int maxPWlength)
{
charStart=start;
charEnd=end;
Hash2Crack=hashValue;
maxLength=maxPWlength;
}
public void run()
{
byte[] myHash2Crack_=Cracker.hexToArray(Hash2Crack);
for(int i=charStart; i<charEnd+1; i++)
{
Cracker.numOfChar[i]////// this is where I am stuck.
}
}
}
