Java example source code file (DHKeyFactory.java)

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Java - Java tags/keywords

biginteger, crypto, dhkeyfactory, dhparameterspec, exception, keypairgenerator, math, pkcs8encodedkeyspec, privatekey, publickey, security, sunjce, x509encodedkeyspec

The DHKeyFactory.java Java example source code

/*
 * Copyright (c) 1998, 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.
 *
 * 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.
 */

/*
 * @test
 * @bug 0000000
 * @summary DHKeyFactory
 * @author Jan Luehe
 */

import java.io.*;
import java.math.BigInteger;
import java.security.*;
import java.security.spec.*;
import java.security.interfaces.*;
import javax.crypto.*;
import javax.crypto.spec.*;
import javax.crypto.interfaces.*;
import com.sun.crypto.provider.SunJCE;

/**
 * This test creates a DH keypair, retrieves the encodings of the DH public and
 * private key, and feeds those encodings to a DH key factory, which parses
 * the encodings and creates a DH public and private key from them.
 */

public class DHKeyFactory {

    private DHKeyFactory() {}

    public static void main(String argv[]) throws Exception {
            // Add JCE to the list of providers
            SunJCE jce = new SunJCE();
            Security.addProvider(jce);

            DHKeyFactory test = new DHKeyFactory();
            test.run();
            System.out.println("Test Passed");
    }

    private void run() throws Exception {

        DHParameterSpec dhSkipParamSpec;

        // use some pre-generated, default DH parameters
        System.err.println("Using SKIP Diffie-Hellman parameters");
        dhSkipParamSpec = new DHParameterSpec(skip1024Modulus,
                                              skip1024Base);

        KeyPairGenerator kpgen = KeyPairGenerator.getInstance("DH");
        kpgen.initialize(dhSkipParamSpec);
        KeyPair kp = kpgen.generateKeyPair();

        // get the public key encoding
        byte[] pubKeyEnc = kp.getPublic().getEncoded();

        // get the private key encoding
        byte[] privKeyEnc = kp.getPrivate().getEncoded();

        KeyFactory kfac = KeyFactory.getInstance("DH");

        X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(pubKeyEnc);
        PublicKey pubKey = kfac.generatePublic(x509KeySpec);

        PKCS8EncodedKeySpec pkcsKeySpec = new PKCS8EncodedKeySpec(privKeyEnc);
        PrivateKey privKey = kfac.generatePrivate(pkcsKeySpec);
    }

    // The 1024 bit Diffie-Hellman modulus values used by SKIP
    private static final byte skip1024ModulusBytes[] = {
        (byte)0xF4, (byte)0x88, (byte)0xFD, (byte)0x58,
        (byte)0x4E, (byte)0x49, (byte)0xDB, (byte)0xCD,
        (byte)0x20, (byte)0xB4, (byte)0x9D, (byte)0xE4,
        (byte)0x91, (byte)0x07, (byte)0x36, (byte)0x6B,
        (byte)0x33, (byte)0x6C, (byte)0x38, (byte)0x0D,
        (byte)0x45, (byte)0x1D, (byte)0x0F, (byte)0x7C,
        (byte)0x88, (byte)0xB3, (byte)0x1C, (byte)0x7C,
        (byte)0x5B, (byte)0x2D, (byte)0x8E, (byte)0xF6,
        (byte)0xF3, (byte)0xC9, (byte)0x23, (byte)0xC0,
        (byte)0x43, (byte)0xF0, (byte)0xA5, (byte)0x5B,
        (byte)0x18, (byte)0x8D, (byte)0x8E, (byte)0xBB,
        (byte)0x55, (byte)0x8C, (byte)0xB8, (byte)0x5D,
        (byte)0x38, (byte)0xD3, (byte)0x34, (byte)0xFD,
        (byte)0x7C, (byte)0x17, (byte)0x57, (byte)0x43,
        (byte)0xA3, (byte)0x1D, (byte)0x18, (byte)0x6C,
        (byte)0xDE, (byte)0x33, (byte)0x21, (byte)0x2C,
        (byte)0xB5, (byte)0x2A, (byte)0xFF, (byte)0x3C,
        (byte)0xE1, (byte)0xB1, (byte)0x29, (byte)0x40,
        (byte)0x18, (byte)0x11, (byte)0x8D, (byte)0x7C,
        (byte)0x84, (byte)0xA7, (byte)0x0A, (byte)0x72,
        (byte)0xD6, (byte)0x86, (byte)0xC4, (byte)0x03,
        (byte)0x19, (byte)0xC8, (byte)0x07, (byte)0x29,
        (byte)0x7A, (byte)0xCA, (byte)0x95, (byte)0x0C,
        (byte)0xD9, (byte)0x96, (byte)0x9F, (byte)0xAB,
        (byte)0xD0, (byte)0x0A, (byte)0x50, (byte)0x9B,
        (byte)0x02, (byte)0x46, (byte)0xD3, (byte)0x08,
        (byte)0x3D, (byte)0x66, (byte)0xA4, (byte)0x5D,
        (byte)0x41, (byte)0x9F, (byte)0x9C, (byte)0x7C,
        (byte)0xBD, (byte)0x89, (byte)0x4B, (byte)0x22,
        (byte)0x19, (byte)0x26, (byte)0xBA, (byte)0xAB,
        (byte)0xA2, (byte)0x5E, (byte)0xC3, (byte)0x55,
        (byte)0xE9, (byte)0x2F, (byte)0x78, (byte)0xC7
    };

    // The SKIP 1024 bit modulus
    private static final BigInteger skip1024Modulus
    = new BigInteger(1, skip1024ModulusBytes);

    // The base used with the SKIP 1024 bit modulus
    private static final BigInteger skip1024Base = BigInteger.valueOf(2);
}