1/*
2 *  Licensed to the Apache Software Foundation (ASF) under one or more
3 *  contributor license agreements.  See the NOTICE file distributed with
4 *  this work for additional information regarding copyright ownership.
5 *  The ASF licenses this file to You under the Apache License, Version 2.0
6 *  (the "License"); you may not use this file except in compliance with
7 *  the License.  You may obtain a copy of the License at
8 *
9 *     http://www.apache.org/licenses/LICENSE-2.0
10 *
11 *  Unless required by applicable law or agreed to in writing, software
12 *  distributed under the License is distributed on an "AS IS" BASIS,
13 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 *  See the License for the specific language governing permissions and
15 *  limitations under the License.
16 */
17
18package org.apache.harmony.security.x509;
19
20import java.io.IOException;
21import org.apache.harmony.security.asn1.ASN1BitString;
22import org.apache.harmony.security.asn1.ASN1Type;
23
24/**
25 * Key Usage Extension (OID = 2.5.29.15).
26 *
27 * The ASN.1 definition for Key Usage Extension is:
28 *
29 * <pre>
30 * id-ce-keyUsage OBJECT IDENTIFIER ::=  { id-ce 15 }
31 *
32 * KeyUsage ::= BIT STRING {
33 *     digitalSignature        (0),
34 *     nonRepudiation          (1),
35 *     keyEncipherment         (2),
36 *     dataEncipherment        (3),
37 *     keyAgreement            (4),
38 *     keyCertSign             (5),
39 *     cRLSign                 (6),
40 *     encipherOnly            (7),
41 *     decipherOnly            (8)
42 * }
43 * </pre>
44 * (as specified in RFC 3280 http://www.ietf.org/rfc/rfc3280.txt)
45 */
46public final class KeyUsage extends ExtensionValue {
47
48    /** The names of the usages. */
49    private static final String[] USAGES = {
50        "digitalSignature",
51        "nonRepudiation",
52        "keyEncipherment",
53        "dataEncipherment",
54        "keyAgreement",
55        "keyCertSign",
56        "cRLSign",
57        "encipherOnly",
58        "decipherOnly",
59    };
60
61    /** the value of extension */
62    private final boolean[] keyUsage;
63
64    /**
65     * Creates the extension object on the base of its encoded form.
66     */
67    public KeyUsage(byte[] encoding) throws IOException {
68        super(encoding);
69        this.keyUsage = (boolean[]) ASN1.decode(encoding);
70    }
71
72    public boolean[] getKeyUsage() {
73        return keyUsage;
74    }
75
76    @Override public byte[] getEncoded() {
77        if (encoding == null) {
78            encoding = ASN1.encode(keyUsage);
79        }
80        return encoding;
81    }
82
83    @Override public void dumpValue(StringBuilder sb, String prefix) {
84        sb.append(prefix).append("KeyUsage [\n");
85        for (int i = 0; i < keyUsage.length; i++) {
86            if (keyUsage[i]) {
87                sb.append(prefix).append("  ").append(USAGES[i]).append('\n');
88            }
89        }
90        sb.append(prefix).append("]\n");
91    }
92
93    /**
94     * X.509 Extension value encoder/decoder.
95     */
96    private static final ASN1Type ASN1 = new ASN1BitString.ASN1NamedBitList(9);
97
98}
99