001 /* SecretKeySpec.java -- Wrapper for secret keys.
002 Copyright (C) 2004 Free Software Foundation, Inc.
003
004 This file is part of GNU Classpath.
005
006 GNU Classpath is free software; you can redistribute it and/or modify
007 it under the terms of the GNU General Public License as published by
008 the Free Software Foundation; either version 2, or (at your option)
009 any later version.
010
011 GNU Classpath is distributed in the hope that it will be useful, but
012 WITHOUT ANY WARRANTY; without even the implied warranty of
013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
014 General Public License for more details.
015
016 You should have received a copy of the GNU General Public License
017 along with GNU Classpath; see the file COPYING. If not, write to the
018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019 02110-1301 USA.
020
021 Linking this library statically or dynamically with other modules is
022 making a combined work based on this library. Thus, the terms and
023 conditions of the GNU General Public License cover the whole
024 combination.
025
026 As a special exception, the copyright holders of this library give you
027 permission to link this library with independent modules to produce an
028 executable, regardless of the license terms of these independent
029 modules, and to copy and distribute the resulting executable under
030 terms of your choice, provided that you also meet, for each linked
031 independent module, the terms and conditions of the license of that
032 module. An independent module is a module which is not derived from
033 or based on this library. If you modify this library, you may extend
034 this exception to your version of the library, but you are not
035 obligated to do so. If you do not wish to do so, delete this
036 exception statement from your version. */
037
038
039 package javax.crypto.spec;
040
041 import java.security.spec.KeySpec;
042
043 import 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 */
057 public 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 }