/* 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,
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 *  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.parameters;

import iaik.pkcs.pkcs11.TokenRuntimeException;
import iaik.pkcs.pkcs11.wrapper.CK_PBE_PARAMS;
import iaik.pkcs.pkcs11.wrapper.Constants;
import iaik.pkcs.pkcs11.wrapper.Functions;



/**
 * This class encapsulates parameters for the Mechanism.PBA_* and
 * Mechanism.PBA_SHA1_WITH_SHA1_HMAC mechanisms.
 *
 * @author Karl Scheibelhofer
 * @version 1.0
 * @invariants (initializationVector_ == null)
 *             or ((initializationVector_ <> null)
 *                 and (initializationVector_.length == 8))
 *             and (password_ <> null)
 *             and (salt_ <> null)
 */
public class PBEParameters implements Parameters {

  /**
   * The 8-byte initialization vector (IV), if an IV is required.
   */
  protected char[] initializationVector_;

  /**
   * The password to be used in the PBE key generation.
   */
  protected char[] password_;

  /**
   * The salt to be used in the PBE key generation.
   */
  protected char[] salt_;

  /**
   * The number of iterations required for the generation.
   */
  protected long iterations_;

  /**
   * Create a new PBEDeriveParameters object with the given attributes.
   *
   * @param initializationVector The 8-byte initialization vector (IV), if an
   *                             IV is required.
   * @param password The password to be used in the PBE key generation.
   * @param salt The salt to be used in the PBE key generation.
   * @param iterations The number of iterations required for the generation.
   * @preconditions (initializationVector == null)
   *                or ((initializationVector <> null)
   *                    and (initializationVector.length == 8))
   *                and (password <> null)
   *                and (salt <> null)
   * @postconditions
   */
  public PBEParameters(char[] initializationVector, char[] password,
                       char[] salt, long iterations)
  {
    if ((initializationVector != null) && (initializationVector.length != 8)) {
      throw new IllegalArgumentException("Argument \"initializationVector\" must be null or must have length " +
                                         "8, if it is not null.");
    }
    if (password == null) {
      throw new NullPointerException("Argument \"password\" must not be null.");
    }
    if (salt == null) {
      throw new NullPointerException("Argument \"salt\" must not be null.");
    }
    initializationVector_ = initializationVector;
    password_ = password;
    salt_ = salt;
    iterations_ = iterations;
  }

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

    try {
      clone = (PBEParameters) super.clone();

      clone.initializationVector_ = (char[]) this.initializationVector_.clone();
      clone.password_ = (char[]) this.password_.clone();
      clone.salt_ = (char[]) this.salt_.clone();
    } catch (CloneNotSupportedException ex) {
      // this must not happen, because this class is cloneable
      throw new TokenRuntimeException("An unexpected clone exception occurred.", ex);
    }

    return clone ;
  }

  /**
   * Get this parameters object as an object of the CK_PBE_PARAMS
   * class.
   *
   * @return This object as a CK_PBE_PARAMS object.
   * @preconditions
   * @postconditions (result <> null)
   */
  public Object getPKCS11ParamsObject() {
    CK_PBE_PARAMS params = new CK_PBE_PARAMS();

    params.pInitVector = initializationVector_;
    params.pPassword = password_;
    params.pSalt = salt_;
    params.ulIteration = iterations_;

    return params ;
  }

  /**
   * Get the 8-byte initialization vector (IV), if an IV is required.
   *
   * @return The 8-byte initialization vector (IV), if an IV is required.
   * @preconditions
   * @postconditions (result == null)
   *                 or ((result <> null)
   *                     and (result.length == 8))
   */
  public char[] getInitializationVector() {
    return initializationVector_ ;
  }

  /**
   * Get the password to be used in the PBE key generation.
   *
   * @return The password to be used in the PBE key generation.
   * @preconditions
   * @postconditions (result <> null)
   */
  public char[] getPassword() {
    return password_ ;
  }

  /**
   * Get the salt to be used in the PBE key generation.
   *
   * @return The salt to be used in the PBE key generation.
   * @preconditions
   * @postconditions (result <> null)
   */
  public char[] getSalt() {
    return salt_ ;
  }

  /**
   * Get the number of iterations required for the generation.
   *
   * @return The number of iterations required for the generation.
   * @preconditions
   * @postconditions
   */
  public long getIterations() {
    return iterations_ ;
  }

  /**
   * Set the 8-byte initialization vector (IV), if an IV is required.
   *
   * @param initializationVector The 8-byte initialization vector (IV), if an
   *                             IV is required.
   * @preconditions (initializationVector == null)
   *                or ((initializationVector <> null)
   *                    and (initializationVector.length == 8))
   * @postconditions
   */
  public void setInitializationVector(char[] initializationVector) {
    if ((initializationVector != null) && (initializationVector.length != 8)) {
      throw new IllegalArgumentException("Argument \"initializationVector\" must be null or must have length " +
                                         "8, if it is not null.");
    }
    initializationVector_ = initializationVector;
  }

  /**
   * Set the password to be used in the PBE key generation.
   *
   * @param password The password to be used in the PBE key generation.
   * @preconditions (password <> null)
   * @postconditions
   */
  public void setPassword(char[] password) {
    if (password == null) {
      throw new NullPointerException("Argument \"password\" must not be null.");
    }
    password_ = password;
  }

  /**
   * Set the salt to be used in the PBE key generation.
   *
   * @param salt The salt to be used in the PBE key generation.
   * @preconditions (salt <> null)
   * @postconditions
   */
  public void setSalt(char[] salt) {
    if (salt == null) {
      throw new NullPointerException("Argument \"salt\" must not be null.");
    }
    salt_ = salt;
  }

  /**
   * Set the number of iterations required for the generation.
   *
   * @param iterations The number of iterations required for the generation.
   * @preconditions
   * @postconditions
   */
  public void setIterations(long iterations) {
    iterations_ = iterations;
  }

  /**
   * Returns the string representation of this object. Do not parse data from
   * this string, it is for debugging only.
   *
   * @return A string representation of this object.
   */
  public String toString() {
    StringBuffer buffer = new StringBuffer();

    buffer.append(Constants.INDENT);
    buffer.append("Initialization Vector: ");
    buffer.append((initializationVector_ != null)
                  ? new String(initializationVector_)
                  : null);
    buffer.append(Constants.NEWLINE);

    buffer.append(Constants.INDENT);
    buffer.append("Password: ");
    buffer.append((password_ != null)
                  ? new String(password_)
                  : null);
    buffer.append(Constants.NEWLINE);

    buffer.append(Constants.INDENT);
    buffer.append("Salt: ");
    buffer.append((salt_ != null)
                  ? new String(salt_)
                  : null);
    buffer.append(Constants.NEWLINE);

    buffer.append(Constants.INDENT);
    buffer.append("Iterations (dec): ");
    buffer.append(iterations_);
    // buffer.append(Constants.NEWLINE);

    return buffer.toString() ;
  }

  /**
   * 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 PBEParameters) {
      PBEParameters other = (PBEParameters) otherObject;
      equal = (this == other)
              || ((Functions.equals(this.initializationVector_, other.initializationVector_)
                  && Functions.equals(this.password_, other.password_)
                  && Functions.equals(this.salt_, other.salt_)
                  && this.iterations_ == other.iterations_));
    }

    return equal ;
  }

  /**
   * The overriding of this method should ensure that the objects of this class
   * work correctly in a hashtable.
   *
   * @return The hash code of this object.
   * @preconditions
   * @postconditions
   */
  public int hashCode() {
    return Functions.hashCode(initializationVector_)
           ^ Functions.hashCode(password_)
           ^ Functions.hashCode(salt_)
           ^ ((int) iterations_) ;
  }

}