1/*
2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26package com.sun.crypto.provider;
27
28import javax.crypto.SecretKey;
29import javax.crypto.SecretKeyFactorySpi;
30import javax.crypto.spec.DESedeKeySpec;
31import java.security.InvalidKeyException;
32import java.security.spec.KeySpec;
33import java.security.spec.InvalidKeySpecException;
34import javax.crypto.spec.SecretKeySpec;
35
36/**
37 * This class implements the DES-EDE key factory of the Sun provider.
38 *
39 * @author Jan Luehe
40 *
41 */
42
43public final class DESedeKeyFactory extends SecretKeyFactorySpi {
44
45    /**
46     * Empty constructor
47     */
48    public DESedeKeyFactory() {
49    }
50
51    /**
52     * Generates a <code>SecretKey</code> object from the provided key
53     * specification (key material).
54     *
55     * @param keySpec the specification (key material) of the secret key
56     *
57     * @return the secret key
58     *
59     * @exception InvalidKeySpecException if the given key specification
60     * is inappropriate for this key factory to produce a public key.
61     */
62    protected SecretKey engineGenerateSecret(KeySpec keySpec)
63        throws InvalidKeySpecException {
64
65        try {
66            if (keySpec instanceof DESedeKeySpec) {
67                return new DESedeKey(((DESedeKeySpec)keySpec).getKey());
68            }
69            if (keySpec instanceof SecretKeySpec) {
70                return new DESedeKey(((SecretKeySpec)keySpec).getEncoded());
71
72            }
73            throw new InvalidKeySpecException
74                ("Inappropriate key specification");
75        } catch (InvalidKeyException e) {
76            throw new InvalidKeySpecException(e.getMessage());
77        }
78    }
79
80    /**
81     * Returns a specification (key material) of the given key
82     * in the requested format.
83     *
84     * @param key the key
85     *
86     * @param keySpec the requested format in which the key material shall be
87     * returned
88     *
89     * @return the underlying key specification (key material) in the
90     * requested format
91     *
92     * @exception InvalidKeySpecException if the requested key specification is
93     * inappropriate for the given key, or the given key cannot be processed
94     * (e.g., the given key has an unrecognized algorithm or format).
95     */
96    protected KeySpec engineGetKeySpec(SecretKey key, Class<?> keySpec)
97        throws InvalidKeySpecException {
98
99        try {
100            if ((key instanceof SecretKey)
101                && (key.getAlgorithm().equalsIgnoreCase("DESede"))
102                && (key.getFormat().equalsIgnoreCase("RAW"))) {
103
104                // Check if requested key spec is amongst the valid ones
105                if (DESedeKeySpec.class.isAssignableFrom(keySpec)) {
106                    return new DESedeKeySpec(key.getEncoded());
107
108                } else {
109                    throw new InvalidKeySpecException
110                        ("Inappropriate key specification");
111                }
112
113            } else {
114                throw new InvalidKeySpecException
115                    ("Inappropriate key format/algorithm");
116            }
117        } catch (InvalidKeyException e) {
118            throw new InvalidKeySpecException("Secret key has wrong size");
119        }
120    }
121
122    /**
123     * Translates a <code>SecretKey</code> object, whose provider may be
124     * unknown or potentially untrusted, into a corresponding
125     * <code>SecretKey</code> object of this key factory.
126     *
127     * @param key the key whose provider is unknown or untrusted
128     *
129     * @return the translated key
130     *
131     * @exception InvalidKeyException if the given key cannot be processed by
132     * this key factory.
133     */
134    protected SecretKey engineTranslateKey(SecretKey key)
135        throws InvalidKeyException {
136
137        try {
138
139            if ((key != null)
140                && (key.getAlgorithm().equalsIgnoreCase("DESede"))
141                && (key.getFormat().equalsIgnoreCase("RAW"))) {
142                // Check if key originates from this factory
143                if (key instanceof com.sun.crypto.provider.DESedeKey) {
144                    return key;
145                }
146                // Convert key to spec
147                DESedeKeySpec desEdeKeySpec
148                    = (DESedeKeySpec)engineGetKeySpec(key,
149                                                      DESedeKeySpec.class);
150                // Create key from spec, and return it
151                return engineGenerateSecret(desEdeKeySpec);
152
153            } else {
154                throw new InvalidKeyException
155                    ("Inappropriate key format/algorithm");
156            }
157
158        } catch (InvalidKeySpecException e) {
159            throw new InvalidKeyException("Cannot translate key");
160        }
161    }
162}
163