1/*
2 * Copyright (c) 1998, 2007, 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 java.math.*;
29import java.io.*;
30import sun.security.x509.AlgorithmId;
31import sun.security.util.*;
32
33
34/**
35 * This class implements the <code>PrivateKeyInfo</code> type,
36 * which is defined in PKCS #8 as follows:
37 *
38 * <pre>
39 * PrivateKeyInfo ::=  SEQUENCE {
40 *     version   INTEGER,
41 *     privateKeyAlgorithm   AlgorithmIdentifier,
42 *     privateKey   OCTET STRING,
43 *     attributes   [0] IMPLICIT Attributes OPTIONAL }
44 * </pre>
45 *
46 * @author Jan Luehe
47 */
48final class PrivateKeyInfo {
49
50    // the version number defined by the PKCS #8 standard
51    private static final BigInteger VERSION = BigInteger.ZERO;
52
53    // the private-key algorithm
54    private AlgorithmId algid;
55
56    // the private-key value
57    private byte[] privkey;
58
59    /**
60     * Constructs a PKCS#8 PrivateKeyInfo from its ASN.1 encoding.
61     */
62    PrivateKeyInfo(byte[] encoded) throws IOException {
63        DerValue val = new DerValue(encoded);
64
65        if (val.tag != DerValue.tag_Sequence)
66            throw new IOException("private key parse error: not a sequence");
67
68        // version
69        BigInteger parsedVersion = val.data.getBigInteger();
70        if (!parsedVersion.equals(VERSION)) {
71            throw new IOException("version mismatch: (supported: " +
72                                  VERSION + ", parsed: " + parsedVersion);
73        }
74
75        // privateKeyAlgorithm
76        this.algid = AlgorithmId.parse(val.data.getDerValue());
77
78        // privateKey
79        this.privkey = val.data.getOctetString();
80
81        // OPTIONAL attributes not supported yet
82    }
83
84    /**
85     * Returns the private-key algorithm.
86     */
87    AlgorithmId getAlgorithm() {
88        return this.algid;
89    }
90}
91