package com.clement.security;

import java.io.IOException;
import java.net.Socket;
import java.net.UnknownHostException;

/**
 *
 * This class will scan the ports of a given IP.
 *
 * @author Mallize
 *
 */
public class PortScanner {
    final static int DEFAULT_LOW_RANGE = 27014;
    final static int DEFAULT_HIGH_RANGE = 27020;
    final static int EXPECTED_PARAMETERS = 3;
	final static int HOST_ONLY = 1;

    public static void main(String[] args) {
        //This is the IP you want to scan
        String host = "127.0.0.1";
        int lowRange = DEFAULT_LOW_RANGE;
        int highRange = DEFAULT_HIGH_RANGE;

        if (args.length == EXPECTED_PARAMETERS) {
            host = args[0];
            lowRange = (int) new Integer(args[1]).intValue();
            highRange = (int) new Integer(args[2]).intValue();
            scanPorts(host, lowRange, highRange);
        }
        else if (args.length == HOST_ONLY){
        	host = args[0];
        	scanPorts(host, lowRange, highRange);
        }
        else {
            scanPorts(host, lowRange, highRange);
        }
    }

    public static void scanPorts(String host, int lowRange, int highRange) {
        Socket connect = null;

		System.out.println("Scanning host " + host);
        for (int count = lowRange; count <= highRange; count++) {
            System.out.print("Checking port " + count + "...");
            try {
                connect = new Socket(host, count);
                System.out.println("Server responding on port " + count + " of " + host);
            }
            catch (UnknownHostException e) {
                System.err.println("Host is invalid.");
                break;
            }
            catch (IOException e) {
                System.out.println("No server found");
            }
            finally {
                try {
                    connect.close();
                }
                catch (Exception e) {
                }
            }
        }
    }
}