javax/crypto/spec/DHGenParameterSpec.java

/*
 * Copyright (c) 1997, 2007, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package javax.crypto.spec;

import java.math.BigInteger;
import java.security.spec.AlgorithmParameterSpec;

/**
 * This class specifies the set of parameters used for generating
 * Diffie-Hellman (system) parameters for use in Diffie-Hellman key
 * agreement. This is typically done by a central
 * authority.
 *
 * <p> The central authority, after computing the parameters, must send this
 * information to the parties looking to agree on a secret key.
 *
 * @author Jan Luehe
 *
 * @see DHParameterSpec
 * @since 1.4
 */
public class DHGenParameterSpec implements AlgorithmParameterSpec {

    // The size in bits of the prime modulus
    private int primeSize;

    // The size in bits of the random exponent (private value)
    private int exponentSize;

    /**
     * Constructs a parameter set for the generation of Diffie-Hellman
     * (system) parameters. The constructed parameter set can be used to
     * initialize an
     * {@link java.security.AlgorithmParameterGenerator AlgorithmParameterGenerator}
     * object for the generation of Diffie-Hellman parameters.
     *
     * @param primeSize the size (in bits) of the prime modulus.
     * @param exponentSize the size (in bits) of the random exponent.
     */
    public DHGenParameterSpec(int primeSize, int exponentSize) {
        this.primeSize = primeSize;
        this.exponentSize = exponentSize;
    }

    /**
     * Returns the size in bits of the prime modulus.
     *
     * @return the size in bits of the prime modulus
     */
    public int getPrimeSize() {
        return this.primeSize;
    }

    /**
     * Returns the size in bits of the random exponent (private value).
     *
     * @return the size in bits of the random exponent (private value)
     */
    public int getExponentSize() {
        return this.exponentSize;
    }
}