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getKey throws an exception on multi-thread env even if it is synchronized

843811May 7 2009 — edited May 20 2009

Hello,

I got the following exception when I used KeyStore#getKey method on multi-thread environment.

java.security.UnrecoverableKeyException: Given final block not properly padded
at com.sun.crypto.provider.SunJCE_z.a(DashoA13*..)
at com.sun.crypto.provider.JceKeyStore.engineGetKey(DashoA13*..)
at java.security.KeyStore.getKey(KeyStore.java:763)
at KeyStoreTest.run(KeyStoreTest.java:43)
at java.lang.Thread.run(Thread.java:619)

This is similar to the topic "Is KeyStore thread safe?"(Jan 29, 2008 8:40 PM), I suppose.
In the topic, KeyStore#getKey should be synchronized because it isn't thread safe.
Therefore I synchronized it, but this problem still occurred.

I used the following program for a duration test.
About in 1 hour, the exception always occurs.

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.security.Key;
import java.security.KeyStore;

public class KeyStoreTest implements Runnable {

public final static String KSFILE = ".\\.jcekeystore"; // Please change here. Your "JCEKS" file name.
public static String sLock = "lock";

public static void main(String[] args) {
Thread[] threads;
int count = 20;
while (true) {
threads = new Thread[count];
for (int i = 0; i < count; i++) {
threads[i] = new Thread(new KeyStoreTest());
threads.start();
}
for (int i = 0; i < count; i++) {
if (threads[i].isAlive()) {
try {
threads[i].join();
} catch (InterruptedException e) {}
}
}
}
}

public void run() {
InputStream is = null;
try {
is = new FileInputStream(KSFILE);
Key key;
synchronized (sLock) {
//System.out.print("start - ");
KeyStore store = KeyStore.getInstance("jceks");
store.load(is, "12345678".toCharArray()); // Please change here. PIN code.
String alias = "alias"; // Please change here. Alias.
String keypassed = "keypasswd"; // Please change here. Key Password.
key = store.getKey(alias, keypassed.toCharArray());
//System.out.println("end");
}
System.out.println(key.getAlgorithm());
} catch (Exception e) {
e.printStackTrace(System.err);
System.exit(0);
} finally {
if (is != null) {
try {
is.close();
} catch (IOException e) {}
is = null;
}
}
}
}

I think there's no problem in my test program.
Do you have any information about the problem?

My test environment is below:
Java : jre1.6.0 update 13
OS : Windows XP

I tested this code with jre1.5.0 update 18, too.
But I didn't get the exception.

Thanks,
Masanori Hayashi

darrylburke

Probably not very efficient, but seems to work ... fairly clean imho :-)

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Rectangle;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextPane;
import javax.swing.SwingUtilities;
import javax.swing.event.CaretEvent;
import javax.swing.event.CaretListener;
import javax.swing.plaf.basic.BasicTextPaneUI;
import javax.swing.text.BadLocationException;

public class LineHighlightTextPane {
   
   public LineHighlightTextPane () {
   }
   
   void makeUI () {
      
      JTextPane textPane = new JTextPane ();
      textPane.setUI (new LineHighlightTextPaneUI (textPane));
      
      JScrollPane scrollPane = new JScrollPane (textPane);
      
      JFrame frame = new JFrame ("Line Highlight Text Pane");
      frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
      frame.setSize (300, 300);
      
      frame.add (scrollPane, BorderLayout.CENTER);
      frame.setVisible (true);
   }
   
   public static void main (String[] args) {
      SwingUtilities.invokeLater (new Runnable () {
         public void run () {
            new LineHighlightTextPane ().makeUI ();
         }
      });
   }
}

class LineHighlightTextPaneUI extends BasicTextPaneUI {
   
   JTextPane tc;
   
   LineHighlightTextPaneUI (JTextPane t) {
      
      tc = t;
      tc.addCaretListener (new CaretListener () {
         public void caretUpdate (CaretEvent e) {
            
            tc.repaint ();
         }
      });
   }
   
   @Override
   public void paintBackground (Graphics g) {
      
      super.paintBackground (g);
      
      try {
         Rectangle rect = modelToView(tc, tc.getCaretPosition ());
         int y = rect.y;
         int h = rect.height;
         g.setColor (Color.YELLOW);
         g.fillRect (0, y, tc.getWidth (), h);
      } catch (BadLocationException ex) {
         ex.printStackTrace();
      }
   }
}

Is that what you wanted or have I misread the requirement?

db

camickr

Or some code that should work on any JTextComponent:

http://www.discoverteenergy.com/files/LinePainter.java

843806

Thanks a lot for the help guys! I was able to do exactly what I needed.

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Added on May 7 2009

#cryptography

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Java Security

getKey throws an exception on multi-thread env even if it is synchronized

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