/* TMMHParameterSpec.java --
   Copyright (C) 2002, 2006  Free Software Foundation, Inc.

This file is a part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
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General Public License for more details.

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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301
USA

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
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package gnu.javax.crypto.jce.spec;

import gnu.java.security.prng.IRandom;

import java.security.spec.AlgorithmParameterSpec;

/**
 * This class represents the algorithm parameters for the Truncated
 * Multi-Modular Hash function for use with JCE-derived instances of
 * {@link gnu.javax.crypto.mac.TMMH16}.
 * <p>
 * This class is little more than a container for the key stream, tag length,
 * and prefix parameters for the TMMH algorithm.
 */
public class TMMHParameterSpec
    implements AlgorithmParameterSpec
{
  /** The keystream. */
  protected IRandom keystream;
  /** The tag length. */
  protected Integer tagLength;
  /** The prefix. */
  protected byte[] prefix;

  /**
   * Create a new parameter specification.
   *
   * @param keystream The (PRNG) key stream.
   * @param tagLength The tag length.
   * @param prefix The prefix.
   */
  public TMMHParameterSpec(IRandom keystream, Integer tagLength, byte[] prefix)
  {
    this.keystream = keystream;
    this.tagLength = tagLength;
    this.prefix = prefix;
  }

  /**
   * Create a new parameter specification with no prefix.
   *
   * @param keystream The (PRNG) key stream.
   * @param tagLength The tag length.
   */
  public TMMHParameterSpec(IRandom keystream, Integer tagLength)
  {
    this(keystream, tagLength, null);
  }

  /**
   * Return the key stream this specification was initialized with.
   *
   * @return The key stream.
   */
  public IRandom getKeystream()
  {
    return keystream;
  }

  /**
   * Return the tag length this specification was initialized with.
   *
   * @return The tag length.
   */
  public Integer getTagLength()
  {
    return tagLength;
  }

  /**
   * Return the prefix, or <code>null</code> if no prefix was specified.
   *
   * @return The prefix.
   */
  public byte[] getPrefix()
  {
    return prefix;
  }
}