001/* SecretKeySpec.java -- Wrapper for secret keys.
002   Copyright (C) 2004  Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038
039package javax.crypto.spec;
040
041import java.security.spec.KeySpec;
042
043import javax.crypto.SecretKey;
044
045/**
046 * This is a simple wrapper around a raw byte array, for ciphers that do
047 * not require any key parameters other than the bytes themselves.
048 *
049 * <p>Since this class implements {@link javax.crypto.SecretKey}, which
050 * in turn extends {@link java.security.Key}, so instances of this class
051 * may be passed directly to the <code>init()</code> methods of {@link
052 * javax.crypto.Cipher}.
053 *
054 * @see javax.crypto.SecretKey
055 * @see javax.crypto.SecretKeyFactory
056 */
057public class SecretKeySpec implements KeySpec, SecretKey
058{
059
060  // Constants and fields.
061  // ------------------------------------------------------------------------
062
063  /** Compatible with JDK1.4. */
064  private static final long serialVersionUID = 6577238317307289933L;
065
066  /** The key bytes. */
067  private byte[] key;
068
069  /** The algorithm's name. */
070  private String algorithm;
071
072  // Constructors.
073  // ------------------------------------------------------------------------
074
075  /**
076   * Create a new secret key spec from an entire byte array.
077   *
078   * @param key       The key material.
079   * @param algorithm The name of the algorithm using this key.
080   */
081  public SecretKeySpec(byte[] key, String algorithm)
082  {
083    this(key, 0, key.length, algorithm);
084  }
085
086  /**
087   * Create a new secret key spec from part of a byte array.
088   *
089   * @param key       The key material.
090   * @param off       The offset at which key material begins.
091   * @param len       The length of key material.
092   * @param algorithm The name of the algorithm using this key.
093   */
094  public SecretKeySpec(byte[] key, int off, int len, String algorithm)
095  {
096    this.key = new byte[len];
097    this.algorithm = algorithm;
098    System.arraycopy(key, off, this.key, 0, len);
099  }
100
101  // Instance methods.
102  // ------------------------------------------------------------------------
103
104  /**
105   * Return the name of the algorithm associated with this secret key.
106   *
107   * @return The algorithm's name.
108   */
109  public String getAlgorithm()
110  {
111    return algorithm;
112  }
113
114  /**
115   * Return the key as a byte array.
116   *
117   * @return The key material.
118   */
119  public byte[] getEncoded()
120  {
121    return key;
122  }
123
124  /**
125   * This key's format, which is always "RAW".
126   *
127   * @return "RAW"
128   */
129  public String getFormat()
130  {
131    return "RAW";
132  }
133
134  public boolean equals(Object o)
135  {
136    if (o instanceof SecretKeySpec)
137      {
138        byte[] okey = ((SecretKeySpec) o).getEncoded();
139        if (key.length != okey.length)
140          return false;
141        for (int i = 0; i < key.length; i++)
142          {
143            if (key[i] != okey[i])
144              return false;
145          }
146        return algorithm.equals(((SecretKeySpec) o).getAlgorithm());
147      }
148    else
149      {
150        return false;
151      }
152  }
153
154  public int hashCode()
155  {
156    int code = 0;
157    for (int i = 0; i < key.length; i++)
158      {
159        code ^= (key[i] & 0xff) << (i << 3 & 31);
160      }
161    return code ^ algorithm.hashCode();
162  }
163}