Hackknowledge 2013 Final bin500 CrackMe

gistfile1.java

import java.util.Scanner;


public class Prism 
{

	public static final int ROTATE_LEFT = 1;
	public static final int ROTATE_RIGHT = 2;
	
	public static int calcmask(int bitstorotate, int direction)
		{
			int mask = 0;
			int c;
			
			if (bitstorotate == 0)
				return 0;
				
		   c = 0x80000000;
		   mask = (c >> bitstorotate);
		   if (direction == ROTATE_RIGHT)
		   {
		   	mask = (c >> (32 - bitstorotate));
		   	mask = ~mask;
		   }
		   else
		   	mask = (c >> bitstorotate);
			
			return mask;
		}
		
	public static int rotl(int value, int bitstorotate, int sizet)
		{
			int tmprslt =0;
			int mask=0;;
			int target=0;
			
			bitstorotate %= sizet;
	
	   		// determine which bits will be impacted by the rotate
			mask = calcmask(bitstorotate, ROTATE_LEFT);
			// shift the mask into the correct place (i.e. if we are delaying with a byte rotate, we
			// need to ensure we have the mask setup for a byte or 8 bits)
			mask >>>= (32 - sizet);
			
			// save off the affected bits
			tmprslt = value & mask;
			
			// perform the actual rotate
			target = (value  << bitstorotate);
			
			// now shift the saved off bits
			tmprslt >>>= (sizet - bitstorotate);
			
			// add the rotated bits back in (in the proper location)
			target |= tmprslt;
	
	   		// now return the result
			return target;
		}
	
	public static byte rotl(byte value, int bitstorotate)
	{
		byte result;
		
		result = (byte) rotl((0x000000ff & value), bitstorotate, 8);
		
		return result;
		
	}
	
	public static String convertHexToString(String hex){
			 
			  StringBuilder sb = new StringBuilder();
			  StringBuilder temp = new StringBuilder();
		 
			  //49204c6f7665204a617661 split into two characters 49, 20, 4c...
			  for( int i=0; i<hex.length()-1; i+=2 ){
		 
			      //grab the hex in pairs
			      String output = hex.substring(i, (i + 2));
			      //convert hex to decimal
			      int decimal = Integer.parseInt(output, 16);
			      //convert the decimal to character
			      sb.append((char)decimal);
		 
			      temp.append(decimal);
			  }
		 
			  return sb.toString();
		  }
		
	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		System.out.println("Name ? : ");
		String str = sc.nextLine();
		String serial = "";
		
		boolean found = false;

		for ( int c= 0; c< str.length(); c++)
		{
			found = false;
			for ( int i = 0x20; i <= 0x7E; i++)
			{
				for (int j= 0x20; j <= 0x7E; j++)
				{
					int x = (i - 0x41) << 4;
					int y = j - 0x41;
					int z = (x + y) ^ 0x43; //0x48
					int f = rotl((byte) z, 3);	
					f = rotl((byte) z, 3);
					f = rotl((byte) z, 3);
					
					if(f == str.charAt(c) && !found)
					{
						found = true;
						serial = serial + convertHexToString((Integer.toHexString(i))) + convertHexToString((Integer.toHexString(j)));
					}
					
				}
			}
		}
		System.out.println(serial);

	}
}