Name: nt126004 Date: 09/14/2001


java version "1.3.1"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.1-b24)
Java HotSpot(TM) Client VM (build 1.3.1-b24, mixed mode)


When converting between RSAPrivateCrtKey and RSAPrivateCrtKeySpec objects, you
can get private keys that throw ArrayIndexOutOfBoundsException when calling
getPublicExponent().

A test program:

import java.security.*;
import java.security.interfaces.*;
import java.security.spec.*;
import java.math.BigInteger;

public class JCATestCase
{
  public static void main(String[] args)
  {
    try
    {
      KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA");
      generator.initialize(512);
      
      KeyPair pair = generator.generateKeyPair();

      RSAPrivateCrtKey privatekey = (RSAPrivateCrtKey) pair.getPrivate();

      RSAPrivateCrtKeySpec spec
        = new RSAPrivateCrtKeySpec(privatekey.getModulus(),
                                   privatekey.getPublicExponent(),
                                   privatekey.getPrivateExponent(),
                                   privatekey.getPrimeP(),
                                   privatekey.getPrimeQ(),
                                   privatekey.getPrimeExponentP(),
                                   privatekey.getPrimeExponentQ(),
                                   privatekey.getCrtCoefficient());

      KeyFactory factory = KeyFactory.getInstance("RSA");
      
      PrivateKey privatekey2 = factory.generatePrivate(spec);

      BigInteger pe = ((RSAPrivateCrtKey) privatekey2).getPublicExponent();

      System.out.print("public exponent: " + pe);
    }
    catch (Exception e)
    {
      e.printStackTrace();
    }
  }
}


Output:

java.lang.ArrayIndexOutOfBoundsException
        at
com.sun.rsajca.JSA_RSAPrivateKey.getPublicExponent([DashoPro-V1.2-120198])
        at JCATestCase.main(JCATestCase.java:33)
(Review ID: 131697)
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