/*  Impostor.java by Mark D. LaDue */

/*  April 12, 1998 */

/*  Copyright (c) 1998 Mark D. LaDue
    You may study, use, modify, and distribute this example for any purpose.
    This example is provided WITHOUT WARRANTY either expressed or implied.  */

/*  This applet retrieves some important private fields from
    theSystemPrincipal by taking advantage of the Principal.encode()
    method.  It then uses that information to construct an impostor,
    a Principal which is distinct from theSystemPrincipal and yet which
    is declared to be equal by the Principal.equals() method.  */

import netscape.applet.*;
import netscape.security.*;
import netscape.util.*;

public class Impostor extends java.applet.Applet implements Runnable {

    Thread controller = null;
    PrivilegeManager privy = null;
    Principal princeps = null;
    Principal impostor = null;
    Principal bogus = null;
    GetPrincipalInfo sys = new GetPrincipalInfo();
    GetPrincipalInfo imp = new GetPrincipalInfo();
    GetPrincipalInfo bog = new GetPrincipalInfo();
    Target tar = null;
    Privilege tarpriv = null;

    public void init() {

    }

    public void start() {
        if (controller == null) {
        controller = new Thread(this);
        controller.start();
        }
    }

    public void stop() {}

    public void run() {

        Control.showConsole();

// Get theSystemPrincipal

        privy = PrivilegeManager.getPrivilegeManager();

        princeps = privy.getSystemPrincipal();

// Get its private fields

        try {
            princeps.encode(sys);
        }
        catch (CodingException ce) {System.out.println("CodingException!");}

// Display them

        System.out.println("\nPrivate fields from theSystemPrinicpal:\n");

        sys.printInfo();

// Create the impostor

        byte[] byter = sys.itsBinaryRep;

        impostor = new Principal(14, byter);

// Get its private fields (though we know them already)

        try {
            impostor.encode(imp);
        }
        catch (CodingException ce) {System.out.println("CodingException!");}

// Display them

        System.out.println("Private fields from the impostor:\n");

        imp.printInfo();

// They're distcinct, but what does the JVM believe?

        if (impostor.equals(princeps)) {
            System.out.println("The impostor and theSystemPrincipal are equal.");
        }
        else {System.out.println("The impostor and theSystemPrincipal are not equal.");}

// Test it further by getting a target that belongs only to theSystemPrincipal

        tar = Target.findTarget("SuperUser", impostor);

        if (tar != null) {System.out.println("SuperUser Target exists for the impostor.");}
        else {System.out.println("SuperUser Target does not exist for the impostor.");}

// Watch what happens with an obviously fake Principal

        byte[] bogusbytes = {(byte)1, (byte)2, (byte)3, (byte)4, (byte)5};

        bogus = new Principal(14, bogusbytes);

        try {
            bogus.encode(bog);
        }
        catch (CodingException ce) {System.out.println("CodingException!");}

        System.out.println("\nPrivate fields from the bogus Principal:\n");

        bog.printInfo();

        if (bogus.equals(princeps)) {
            System.out.println("The bogus Principal and theSystemPrincipal are equal.");
        }
        else {System.out.println("The bogus Principal and theSystemPrincipal are not equal.");}

        tar = Target.findTarget("SuperUser", bogus);

        if (tar != null) {System.out.println("SuperUser Target exists for the bogus Principal.");}
        else {System.out.println("SuperUser Target does not exist for the bogus Principal.");}

    }
}