gnu.java.security.sig.rsa

Class EMSA_PKCS1_V1_5

Implemented Interfaces:
Cloneable

public class EMSA_PKCS1_V1_5
extends Object
implements Cloneable

An implementation of the EMSA-PKCS1-V1.5 encoding scheme.

EMSA-PKCS1-V1.5 is parameterised by the choice of hash function Hash and hLen which denotes the length in octets of the hash function output.

References:

  1. Public-Key Cryptography Standards (PKCS) #1:
    RSA Cryptography Specifications Version 2.1.
    Jakob Jonsson and Burt Kaliski.

Method Summary

Object
clone()
byte[]
encode(byte[] mHash, int emLen)
Frames the hash of a message, along with an ID of the hash function in a DER sequence according to the specifications of EMSA-PKCS1-V1.5 as described in RFC-3447 (see class documentation).
static EMSA_PKCS1_V1_5
getInstance(String mdName)
Returns an instance of this object given a designated name of a hash function.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

clone

public Object clone()
Overrides:
clone in interface Object

encode

public byte[] encode(byte[] mHash,
                     int emLen)
Frames the hash of a message, along with an ID of the hash function in a DER sequence according to the specifications of EMSA-PKCS1-V1.5 as described in RFC-3447 (see class documentation).
Parameters:
mHash - the byte sequence resulting from applying the message digest algorithm Hash to the message M.
emLen - intended length in octets of the encoded message, at least tLen + 11, where tLen is the octet length of the DER encoding T of a certain value computed during the encoding operation.
Returns:
encoded message, an octet string of length emLen.
Throws:
IllegalArgumentException - if the message is too long, or if the intended encoded message length is too short.

getInstance

public static final EMSA_PKCS1_V1_5 getInstance(String mdName)
Returns an instance of this object given a designated name of a hash function.
Parameters:
mdName - the canonical name of a hash function.
Returns:
an instance of this object configured for use with the designated options.
Throws:
UnsupportedOperationException - if the hash function is not implemented or does not have an ID listed in RFC-3447.

EMSA_PKCS1_V1_5.java -- Copyright (C) 2003, 2006 Free Software Foundation, Inc. This file is a part of GNU Classpath. GNU Classpath is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. GNU Classpath is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Classpath; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Linking this library statically or dynamically with other modules is making a combined work based on this library. Thus, the terms and conditions of the GNU General Public License cover the whole combination. As a special exception, the copyright holders of this library give you permission to link this library with independent modules to produce an executable, regardless of the license terms of these independent modules, and to copy and distribute the resulting executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions of the license of that module. An independent module is a module which is not derived from or based on this library. If you modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version.