001 /*
002 * Copyright 2003-2006 Sun Microsystems, Inc. All Rights Reserved.
003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004 *
005 * This code is free software; you can redistribute it and/or modify it
006 * under the terms of the GNU General Public License version 2 only, as
007 * published by the Free Software Foundation. Sun designates this
008 * particular file as subject to the "Classpath" exception as provided
009 * by Sun in the LICENSE file that accompanied this code.
010 *
011 * This code is distributed in the hope that it will be useful, but WITHOUT
012 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
013 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
014 * version 2 for more details (a copy is included in the LICENSE file that
015 * accompanied this code).
016 *
017 * You should have received a copy of the GNU General Public License version
018 * 2 along with this work; if not, write to the Free Software Foundation,
019 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
020 *
021 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
022 * CA 95054 USA or visit www.sun.com if you need additional information or
023 * have any questions.
024 */
025
026 package java.security.spec;
027
028 import java.security.spec.AlgorithmParameterSpec;
029
030 /**
031 * This class specifies the set of parameters used with mask generation
032 * function MGF1 in OAEP Padding and RSA-PSS signature scheme, as
033 * defined in the
034 * <a href="http://www.ietf.org/rfc/rfc3447.txt">PKCS #1 v2.1</a>
035 * standard.
036 *
037 * <p>Its ASN.1 definition in PKCS#1 standard is described below:
038 * <pre>
039 * MGF1Parameters ::= OAEP-PSSDigestAlgorthms
040 * </pre>
041 * where
042 * <pre>
043 * OAEP-PSSDigestAlgorithms ALGORITHM-IDENTIFIER ::= {
044 * { OID id-sha1 PARAMETERS NULL }|
045 * { OID id-sha256 PARAMETERS NULL }|
046 * { OID id-sha384 PARAMETERS NULL }|
047 * { OID id-sha512 PARAMETERS NULL },
048 * ... -- Allows for future expansion --
049 * }
050 * </pre>
051 * @see PSSParameterSpec
052 * @see javax.crypto.spec.OAEPParameterSpec
053 *
054 * @author Valerie Peng
055 *
056 * @version 1.11, 05/05/07
057 * @since 1.5
058 */
059 public class MGF1ParameterSpec implements AlgorithmParameterSpec {
060
061 /**
062 * The MGF1ParameterSpec which uses "SHA-1" message digest.
063 */
064 public static final MGF1ParameterSpec SHA1 = new MGF1ParameterSpec(
065 "SHA-1");
066 /**
067 * The MGF1ParameterSpec which uses "SHA-256" message digest.
068 */
069 public static final MGF1ParameterSpec SHA256 = new MGF1ParameterSpec(
070 "SHA-256");
071 /**
072 * The MGF1ParameterSpec which uses "SHA-384" message digest.
073 */
074 public static final MGF1ParameterSpec SHA384 = new MGF1ParameterSpec(
075 "SHA-384");
076 /**
077 * The MGF1ParameterSpec which uses SHA-512 message digest.
078 */
079 public static final MGF1ParameterSpec SHA512 = new MGF1ParameterSpec(
080 "SHA-512");
081
082 private String mdName;
083
084 /**
085 * Constructs a parameter set for mask generation function MGF1
086 * as defined in the PKCS #1 standard.
087 *
088 * @param mdName the algorithm name for the message digest
089 * used in this mask generation function MGF1.
090 * @exception NullPointerException if <code>mdName</code> is null.
091 */
092 public MGF1ParameterSpec(String mdName) {
093 if (mdName == null) {
094 throw new NullPointerException("digest algorithm is null");
095 }
096 this .mdName = mdName;
097 }
098
099 /**
100 * Returns the algorithm name of the message digest used by the mask
101 * generation function.
102 *
103 * @return the algorithm name of the message digest.
104 */
105 public String getDigestAlgorithm() {
106 return mdName;
107 }
108 }
|