Is it an bug in SunJCE Cipher implementation?

Question

i encountered an issue running the following piece of codes
public static void main(String[] args) {
          try {
               String clearText = args[0];
               KeyGenerator kg = KeyGenerator.getInstance("DESede", "SunJCE");
               kg.init(new SecureRandom());
               SecretKey secretKey = kg.generateKey();
               Cipher c = Cipher.getInstance("DESede/ECB/PKCS5Padding", "SunJCE");
               c.init(Cipher.ENCRYPT_MODE, secretKey);
               c.update(clearText.getBytes("ISO8859_1"));
               byte[] encrypted = c.doFinal();
               System.out.println("Size of encrypted byte array:" + encrypted.length);
               c.init(Cipher.DECRYPT_MODE, secretKey);
               c.update(encrypted);
               byte[] decrypted = c.doFinal();
               System.out.println("Size of encrypted byte array:" + decrypted.length);
               String msg = new String(decrypted, "ISO8859_1");
               System.out.println("Decrypted text:" + msg);     
          } catch (Exception e) {
               System.out.println(e.toString());
when starting with comandline parameter as "1", "12", ...., until "1234567", it runs fine, the size of encrypted byte array is 8, as expected, and the decrypted text mataches the original. however, when given the parameter as "12345678", a 8-character string, the DES block size, the size of the encrypted byte array is 0, no encrypted data generated. when given the parameter as "123456789", the size of encypted byte array is 8, the size of decrypted byte array is 1, and decrypted text is "9", the first block of the original data is lost. This pattern remains with other input data, seems when the size of input string is a multiple of DES block size, the entire data is lost. when it is not, then only the one in the last block remains.
it's hard for me to believe this is caused by a bug in SunJCE, it's so obvious that it would be reported long ago, but i also could not find any coding issue in the code above. Any one can give me some suggestions/hints? i really appreciate it.
I run the code on winXP box, with sun jdk 1.5.0_06 or jdk 1.4.2_11, same result. i also run the code on my linux box, with sun jdk 1.4.1_03, same result.

Answer 1

Please use code tags the next time you post.
The bug is in your code. You're throwing away the byte [] returned by Cipher.update().
In your small example you're better off just skipping the update method and only using the doFinal(byte []) method e.g. ...
Cipher c = Cipher.getInstance("DESede/ECB/PKCS5Padding", "SunJCE");
c.init(Cipher.ENCRYPT_MODE, secretKey);
byte[] encrypted = c.doFinal(clearText.getBytes("ISO8859_1"));