1/*
2 * Copyright (c) 2003, 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
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23 * questions.
24 */
25
26package javax.crypto.spec;
27
28import java.math.BigInteger;
29import java.security.spec.AlgorithmParameterSpec;
30import java.security.spec.MGF1ParameterSpec;
31
32/**
33 * This class specifies the set of parameters used with OAEP Padding,
34 * as defined in the
35 * <a href="http://www.ietf.org/rfc/rfc3447.txt">PKCS #1</a>
36 * standard.
37 *
38 * Its ASN.1 definition in PKCS#1 standard is described below:
39 * <pre>
40 * RSAES-OAEP-params ::= SEQUENCE {
41 *   hashAlgorithm      [0] OAEP-PSSDigestAlgorithms     DEFAULT sha1,
42 *   maskGenAlgorithm   [1] PKCS1MGFAlgorithms  DEFAULT mgf1SHA1,
43 *   pSourceAlgorithm   [2] PKCS1PSourceAlgorithms  DEFAULT pSpecifiedEmpty
44 * }
45 * </pre>
46 * where
47 * <pre>
48 * OAEP-PSSDigestAlgorithms    ALGORITHM-IDENTIFIER ::= {
49 *   { OID id-sha1 PARAMETERS NULL   }|
50 *   { OID id-sha256 PARAMETERS NULL }|
51 *   { OID id-sha384 PARAMETERS NULL }|
52 *   { OID id-sha512 PARAMETERS NULL },
53 *   ...  -- Allows for future expansion --
54 * }
55 * PKCS1MGFAlgorithms    ALGORITHM-IDENTIFIER ::= {
56 *   { OID id-mgf1 PARAMETERS OAEP-PSSDigestAlgorithms },
57 *   ...  -- Allows for future expansion --
58 * }
59 * PKCS1PSourceAlgorithms    ALGORITHM-IDENTIFIER ::= {
60 *   { OID id-pSpecified PARAMETERS OCTET STRING },
61 *   ...  -- Allows for future expansion --
62 * }
63 * </pre>
64 * <p>Note: the OAEPParameterSpec.DEFAULT uses the following:
65 *     message digest  -- "SHA-1"
66 *     mask generation function (mgf) -- "MGF1"
67 *     parameters for mgf -- MGF1ParameterSpec.SHA1
68 *     source of encoding input -- PSource.PSpecified.DEFAULT
69 *
70 * @see java.security.spec.MGF1ParameterSpec
71 * @see PSource
72 *
73 * @author Valerie Peng
74 *
75 * @since 1.5
76 */
77public class OAEPParameterSpec implements AlgorithmParameterSpec {
78
79    private String mdName = "SHA-1";
80    private String mgfName = "MGF1";
81    private AlgorithmParameterSpec mgfSpec = MGF1ParameterSpec.SHA1;
82    private PSource pSrc = PSource.PSpecified.DEFAULT;
83
84    /**
85     * The OAEP parameter set with all default values.
86     */
87    public static final OAEPParameterSpec DEFAULT = new OAEPParameterSpec();
88
89    /**
90     * Constructs a parameter set for OAEP padding as defined in
91     * the PKCS #1 standard using the default values.
92     */
93    private OAEPParameterSpec() {
94    }
95
96    /**
97     * Constructs a parameter set for OAEP padding as defined in
98     * the PKCS #1 standard using the specified message digest
99     * algorithm <code>mdName</code>, mask generation function
100     * algorithm <code>mgfName</code>, parameters for the mask
101     * generation function <code>mgfSpec</code>, and source of
102     * the encoding input P <code>pSrc</code>.
103     *
104     * @param mdName the algorithm name for the message digest.
105     * @param mgfName the algorithm name for the mask generation
106     * function.
107     * @param mgfSpec the parameters for the mask generation function.
108     * If null is specified, null will be returned by getMGFParameters().
109     * @param pSrc the source of the encoding input P.
110     * @exception NullPointerException if <code>mdName</code>,
111     * <code>mgfName</code>, or <code>pSrc</code> is null.
112     */
113    public OAEPParameterSpec(String mdName, String mgfName,
114                             AlgorithmParameterSpec mgfSpec,
115                             PSource pSrc) {
116        if (mdName == null) {
117            throw new NullPointerException("digest algorithm is null");
118        }
119        if (mgfName == null) {
120            throw new NullPointerException("mask generation function " +
121                                           "algorithm is null");
122        }
123        if (pSrc == null) {
124            throw new NullPointerException("source of the encoding input " +
125                                           "is null");
126        }
127        this.mdName =  mdName;
128        this.mgfName =  mgfName;
129        this.mgfSpec =  mgfSpec;
130        this.pSrc =  pSrc;
131    }
132
133    /**
134     * Returns the message digest algorithm name.
135     *
136     * @return the message digest algorithm name.
137     */
138    public String getDigestAlgorithm() {
139        return mdName;
140    }
141
142    /**
143     * Returns the mask generation function algorithm name.
144     *
145     * @return the mask generation function algorithm name.
146     */
147    public String getMGFAlgorithm() {
148        return mgfName;
149    }
150
151    /**
152     * Returns the parameters for the mask generation function.
153     *
154     * @return the parameters for the mask generation function.
155     */
156    public AlgorithmParameterSpec getMGFParameters() {
157        return mgfSpec;
158    }
159
160    /**
161     * Returns the source of encoding input P.
162     *
163     * @return the source of encoding input P.
164     */
165    public PSource getPSource() {
166        return pSrc;
167    }
168}
169