/* Copyright  (c) 2002 Graz University of Technology. All rights reserved.
 *
 * Redistribution and use in  source and binary forms, with or without 
 * modification, are permitted  provided that the following conditions are met:
 *
 * 1. Redistributions of  source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in  binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *  
 * 3. The end-user documentation included with the redistribution, if any, must
 *    include the following acknowledgment:
 * 
 *    "This product includes software developed by IAIK of Graz University of
 *     Technology."
 * 
 *    Alternately, this acknowledgment may appear in the software itself, if 
 *    and wherever such third-party acknowledgments normally appear.
 *  
 * 4. The names "Graz University of Technology" and "IAIK of Graz University of
 *    Technology" must not be used to endorse or promote products derived from 
 *    this software without prior written permission.
 *  
 * 5. Products derived from this software may not be called 
 *    "IAIK PKCS Wrapper", nor may "IAIK" appear in their name, without prior 
 *    written permission of Graz University of Technology.
 *  
 *  THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESSED OR IMPLIED
 *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 *  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 *  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE LICENSOR BE
 *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 *  OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 *  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
 *  OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 *  ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 *  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 *  OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *  POSSIBILITY  OF SUCH DAMAGE.
 */

package iaik.pkcs.pkcs11.objects;

import iaik.pkcs.pkcs11.Session;
import iaik.pkcs.pkcs11.TokenException;
import iaik.pkcs.pkcs11.wrapper.Constants;



/**
 * Objects of this class represent DSA private keys as specified by PKCS#11
 * v2.11.
 *
 * @author Karl Scheibelhofer
 * @version 1.0
 * @invariants (prime_ <> null)
 *             and (subprime_ <> null)
 *             and (base_ <> null)
 *             and (value_ <> null)
 */
public class DSAPrivateKey extends PrivateKey {

  /**
   * The prime (p) of this DSA key.
   */
  protected ByteArrayAttribute prime_;

  /**
   * The subprime (q) of this DSA key.
   */
  protected ByteArrayAttribute subprime_;

  /**
   * The base (g) of this DSA key.
   */
  protected ByteArrayAttribute base_;

  /**
   * The private value (x) of this DSA key.
   */
  protected ByteArrayAttribute value_;

  /**
   * Deafult Constructor.
   *
   * @preconditions
   * @postconditions
   */
  public DSAPrivateKey() {
    super();
    keyType_.setLongValue(KeyType.DSA);
  }

  /**
   * Called by getInstance to create an instance of a PKCS#11 DSA private key.
   *
   * @param session The session to use for reading attributes.
   *                This session must have the appropriate rights; i.e.
   *                it must be a user-session, if it is a private object.
   * @param objectHandle The object handle as given from the PKCS#111 module.
   * @exception TokenException If getting the attributes failed.
   * @preconditions (session <> null)
   * @postconditions
   */
  protected DSAPrivateKey(Session session, long objectHandle)
      throws TokenException
  {
    super(session, objectHandle);
    keyType_.setLongValue(KeyType.DSA);
  }

  /**
   * The getInstance method of the PrivateKey class uses this method to create
   * an instance of a PKCS#11 DSA private key.
   *
   * @param session The session to use for reading attributes.
   *                This session must have the appropriate rights; i.e.
   *                it must be a user-session, if it is a private object.
   * @param objectHandle The object handle as given from the PKCS#111 module.
   * @return The object representing the PKCS#11 object.
   *         The returned object can be casted to the
   *         according sub-class.
   * @exception TokenException If getting the attributes failed.
   * @preconditions (session <> null)
   * @postconditions (result <> null) 
   */
  public static Object getInstance(Session session, long objectHandle)
      throws TokenException
  {
    return new DSAPrivateKey(session, objectHandle) ;
  }

  /**
   * Put all attributes of the given object into the attributes table of this
   * object. This method is only static to be able to access invoke the
   * implementation of this method for each class separately (see use in
   * clone()).
   *
   * @param object The object to handle.
   * @preconditions (object <> null)
   * @postconditions
   */
  protected static void putAttributesInTable(DSAPrivateKey object) {
    if (object == null) {
      throw new NullPointerException("Argument \"object\" must not be null.");
    }

    object.attributeTable_.put(Attribute.PRIME, object.prime_);
    object.attributeTable_.put(Attribute.SUBPRIME, object.subprime_);
    object.attributeTable_.put(Attribute.BASE, object.base_);
    object.attributeTable_.put(Attribute.VALUE, object.value_);
  }

  /**
   * Allocates the attribute objects for this class and adds them to the
   * attribute table.
   *
   * @preconditions
   * @postconditions
   */
  protected void allocateAttributes() {
    super.allocateAttributes();

    prime_ = new ByteArrayAttribute(Attribute.PRIME);
    subprime_ = new ByteArrayAttribute(Attribute.SUBPRIME);
    base_ = new ByteArrayAttribute(Attribute.BASE);
    value_ = new ByteArrayAttribute(Attribute.VALUE);

    putAttributesInTable(this);
  }

  /**
   * Create a (deep) clone of this object.
   *
   * @return A clone of this object.
   * @preconditions
   * @postconditions (result <> null)
   *                 and (result instanceof DSAPrivateKey)
   *                 and (result.equals(this))
   */
  public java.lang.Object clone() {
    DSAPrivateKey clone = (DSAPrivateKey) super.clone();

    clone.prime_ = (ByteArrayAttribute) this.prime_.clone();
    clone.subprime_ = (ByteArrayAttribute) this.subprime_.clone();
    clone.base_ = (ByteArrayAttribute) this.base_.clone();
    clone.value_ = (ByteArrayAttribute) this.value_.clone();

    putAttributesInTable(clone); // put all cloned attributes into the new table

    return clone ;
  }

  /**
   * Compares all member variables of this object with the other object.
   * Returns only true, if all are equal in both objects.
   *
   * @param otherObject The other object to compare to.
   * @return True, if other is an instance of this class and all member
   *         variables of both objects are equal. False, otherwise.
   * @preconditions
   * @postconditions
   */
  public boolean equals(java.lang.Object otherObject) {
    boolean equal = false;

    if (otherObject instanceof DSAPrivateKey) {
      DSAPrivateKey other = (DSAPrivateKey) otherObject;
      equal = (this == other)
              || (super.equals(other)
                  && this.prime_.equals(other.prime_)
                  && this.subprime_.equals(other.subprime_)
                  && this.base_.equals(other.base_)
                  && this.value_.equals(other.value_));
    }

    return equal ;
  }

  /**
   * Gets the prime attribute of this DSA key.
   *
   * @return The prime attribute.
   * @preconditions
   * @postconditions (result <> null)
   */
  public ByteArrayAttribute getPrime() {
    return prime_ ;
  }

  /**
   * Gets the subprime attribute of this DSA key.
   *
   * @return The subprime attribute.
   * @preconditions
   * @postconditions (result <> null)
   */
  public ByteArrayAttribute getSubprime() {
    return subprime_ ;
  }

  /**
   * Gets the base attribute of this DSA key.
   *
   * @return The base attribute.
   * @preconditions
   * @postconditions (result <> null)
   */
  public ByteArrayAttribute getBase() {
    return base_ ;
  }

  /**
   * Gets the value attribute of this DSA key.
   *
   * @return The value attribute.
   * @preconditions
   * @postconditions (result <> null)
   */
  public ByteArrayAttribute getValue() {
    return value_ ;
  }

  /**
   * Read the values of the attributes of this object from the token.
   *
   * @param session The session handle to use for reading attributes.
   *                This session must have the appropriate rights; i.e.
   *                it must be a user-session, if it is a private object.
   * @exception TokenException If getting the attributes failed.
   * @preconditions (session <> null)
   * @postconditions
   */
  public void readAttributes(Session session)
      throws TokenException
  {
    super.readAttributes(session);

    Object.getAttributeValue(session, objectHandle_, prime_);
    Object.getAttributeValue(session, objectHandle_, subprime_);
    Object.getAttributeValue(session, objectHandle_, base_);
    Object.getAttributeValue(session, objectHandle_, value_);
  }
  
  /**
   * This method returns a string representation of the current object. The
   * output is only for debugging purposes and should not be used for other
   * purposes.
   *
   * @return A string presentation of this object for debugging output.
   * @preconditions
   * @postconditions (result <> null)
   */
  public String toString() {
    StringBuffer buffer = new StringBuffer(1024);

    buffer.append(super.toString());

    buffer.append(Constants.NEWLINE);
    buffer.append(Constants.INDENT);
    buffer.append("Prime (hex): ");
    buffer.append(prime_.toString());

    buffer.append(Constants.NEWLINE);
    buffer.append(Constants.INDENT);
    buffer.append("Subprime (hex): ");
    buffer.append(subprime_.toString());

    buffer.append(Constants.NEWLINE);
    buffer.append(Constants.INDENT);
    buffer.append("Base (hex): ");
    buffer.append(base_.toString());

    buffer.append(Constants.NEWLINE);
    buffer.append(Constants.INDENT);
    buffer.append("Value (hex): ");
    buffer.append(value_.toString());

    return buffer.toString() ;
  }

}
