Java example source code file (TestKeyPairGeneratorLength.java)

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Java - Java tags/keywords

exception, keypair, rsa, rsapublickey, security, sunrsasign, testkeypairgeneratorlength

The TestKeyPairGeneratorLength.java Java example source code

/*
 * Copyright (c) 2004, 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     5078280
 * @summary make sure generated key pairs are exactly the requested length
 * @author  Andreas Sterbenz
 */

import java.security.*;
import java.security.interfaces.*;

public class TestKeyPairGeneratorLength {

    public static void main(String[] args) throws Exception {
        test(512);
        test(513);
        System.out.println("Done.");
    }

    private static void test(int len) throws Exception {
        KeyPairGenerator kpg = KeyPairGenerator.getInstance("RSA", "SunRsaSign");
        kpg.initialize(len);
        for (int i = 0; i < 6; i++) {
            System.out.println("Generating keypair " + len + " bit keypair " + (i + 1) + "...");
            KeyPair kp = kpg.generateKeyPair();
            RSAPublicKey key = (RSAPublicKey)kp.getPublic();
            int k = key.getModulus().bitLength();
            if (k != len) {
                throw new Exception("length mismatch: " + k);
            }
        }
    }

}