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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

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 * 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).

 *

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 * 2 along with this work; if not, write to the Free Software Foundation,

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/**

 * @test

 * @bug 4853305 4865198 4888410 4963723

 * @summary Verify that the RSA KeyPairGenerator works

 * @author Andreas Sterbenz

 */

import java.io.*;

import java.util.*;

import java.math.BigInteger;

import java.security.*;

import java.security.interfaces.*;

import java.security.spec.*;

public class TestKeyPairGenerator {

    private static Provider provider;

    private static byte[] data;

    private static void testSignature(String algorithm, PrivateKey privateKey, PublicKey publicKey) throws Exception {

        System.out.println("Testing " + algorithm + "...");

        Signature s = Signature.getInstance(algorithm, provider);

        s.initSign(privateKey);

        s.update(data);

        byte[] sig = s.sign();

        s.initVerify(publicKey);

        s.update(data);

        boolean result = s.verify(sig);

        if (result == false) {

            throw new Exception("Verification failed");

        }

    }

    private static void test(PrivateKey privateKey, PublicKey publicKey) throws Exception {

        testSignature("MD2withRSA", privateKey, publicKey);

        testSignature("MD5withRSA", privateKey, publicKey);

        testSignature("SHA1withRSA", privateKey, publicKey);

        testSignature("SHA224withRSA", privateKey, publicKey);

        testSignature("SHA256withRSA", privateKey, publicKey);

        RSAPublicKey rsaKey = (RSAPublicKey)publicKey;

        if (rsaKey.getModulus().bitLength() > 512) {

            // for SHA384 and SHA512 the data is too long for 512 bit keys

            testSignature("SHA384withRSA", privateKey, publicKey);

            testSignature("SHA512withRSA", privateKey, publicKey);

        }

    }

    // regression test for 4865198

    private static void testInvalidSignature(KeyPair kp1, KeyPair kp2) throws Exception {

        System.out.println("Testing signature with incorrect key...");

        Signature sig = Signature.getInstance("MD5withRSA", provider);

        sig.initSign(kp1.getPrivate());

        byte[] data = new byte[100];

        sig.update(data);

        byte[] signature = sig.sign();

        sig.initVerify(kp1.getPublic());

        sig.update(data);

        if (sig.verify(signature) == false) {

            throw new Exception("verification failed");

        }

        sig.initVerify(kp2.getPublic());

        sig.update(data);

        // verify needs to return false and not throw an Exception

        try {

            if (sig.verify(signature)) {

                throw new Exception("verification unexpectedly succeeded");

            }

        } catch (SignatureException se) {

            // Yet another kind of failure, OK.

        }

    }

    public static void main(String[] args) throws Exception {

        long start = System.currentTimeMillis();

        provider = Security.getProvider("SunRsaSign");

        data = new byte[2048];

        // keypair generation is very slow, test only a few short keys

        int[] keyLengths = {512, 512, 1024};

        BigInteger[] pubExps = {null, BigInteger.valueOf(3), null};

        KeyPair[] keyPairs = new KeyPair[3];

        new Random().nextBytes(data);

        KeyPairGenerator kpg = KeyPairGenerator.getInstance("RSA", provider);

        for (int i = 0; i < keyLengths.length; i++) {

            int len = keyLengths[i];

            BigInteger exp = pubExps[i];

            System.out.println("Generating " + len + " bit keypair...");

            if (exp == null) {

                kpg.initialize(len);

            } else {

                kpg.initialize(new RSAKeyGenParameterSpec(len, exp));

            }

            KeyPair kp = kpg.generateKeyPair();

            keyPairs[i] = kp;

            RSAPublicKey publicKey = (RSAPublicKey)kp.getPublic();

            System.out.println(publicKey);

            RSAPrivateCrtKey privateKey = (RSAPrivateCrtKey)kp.getPrivate();

            if (publicKey.getModulus().equals(privateKey.getModulus()) == false) {

                throw new Exception("Moduli do not match");

            }

            if (publicKey.getPublicExponent().equals(privateKey.getPublicExponent()) == false) {

                throw new Exception("Exponents do not match");

            }

            int keyLen = publicKey.getModulus().bitLength();

            if ((keyLen > len) || (keyLen < len - 1)) {

                throw new Exception("Incorrect key length: " + keyLen);

            }

            if (exp != null) {

                if (exp.equals(publicKey.getPublicExponent()) == false) {

                    throw new Exception("Incorrect exponent");

                }

            }

            test(privateKey, publicKey);

        }

        testInvalidSignature(keyPairs[0], keyPairs[1]);

        testInvalidSignature(keyPairs[0], keyPairs[2]);

        testInvalidSignature(keyPairs[2], keyPairs[0]);

        long stop = System.currentTimeMillis();

        System.out.println("All tests passed (" + (stop - start) + " ms).");

    }

}