/* DHParameterSpec.java -- Parameters for Diffie-Hellman keys. Copyright (C) 2004 Free Software Foundation, Inc. This file is 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, 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; see the file COPYING. If not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 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. */ package javax.crypto.spec; import java.math.BigInteger; import java.security.spec.AlgorithmParameterSpec; /** * The base set of parameters necessary to perform Diffie-Hellman key * exchange. Each party in the key exchange shares these parameters. * *

Each set of parameters consists of a base generator * g, a prime modulus p, and an * optional length, in bits, of the private exponent. * *

See PKCS * #3 - Diffie-Hellman Key Agreement Standard for more information. * * @author Casey Marshall (csm@gnu.org) * @since 1.4 * @see javax.crypto.KeyAgreement */ public class DHParameterSpec implements AlgorithmParameterSpec { // Variables. // ------------------------------------------------------------------------ /** The base generator g. */ private BigInteger g; /** The prime modulus p. */ private BigInteger p; /** The length, in bits, of the private exponent. */ private int l; // Constructors. // ------------------------------------------------------------------------ /** * Create a new set of Diffie-Hellman parameters. * * @param p The prime modulus. * @param g The base generator. */ public DHParameterSpec(BigInteger p, BigInteger g) { this(p, g, 0); } /** * Create a new set of Diffie-Hellman parameters. * * @param p The prime modulus. * @param g The base generator. * @param l The size of the private exponent, in bits. */ public DHParameterSpec(BigInteger p, BigInteger g, int l) { this.p = p; this.g = g; this.l = l; } // Instance methods. // ------------------------------------------------------------------------ /** * Get the base generator, g. * * @return The base generator g. */ public BigInteger getG() { return g; } /** * Get the length of the private exponent, in bits. * * @return The length of the private exponent, in bits, or 0 if this * has not been explicitly set. */ public int getL() { return l; } /** * Get the prime modulus, p. * * @return The prime modulus, p. */ public BigInteger getP() { return p; } }