/*

 * Copyright (c) 2013, 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 8020081

 * @summary encryption/decryption test for using OAEPPadding with

 * OAEPParameterSpec specified and not specified during a Cipher.init().

 * @author Anthony Scarpino

 */

import java.util.Arrays;

import java.security.Security;

import java.security.Provider;

import java.security.KeyPair;

import java.security.KeyPairGenerator;

import java.security.interfaces.RSAPrivateKey;

import java.security.interfaces.RSAPublicKey;

import java.security.spec.MGF1ParameterSpec;

import javax.crypto.Cipher;

import javax.crypto.spec.OAEPParameterSpec;

import javax.crypto.IllegalBlockSizeException;

import javax.crypto.spec.PSource;

public class TestOAEPPadding {

    private static RSAPrivateKey privateKey;

    private static RSAPublicKey publicKey;

    static Provider cp;

    static boolean failed = false;

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

        cp = Security.getProvider("SunJCE");

        System.out.println("Testing provider " + cp.getName() + "...");

        Provider kfp = Security.getProvider("SunRsaSign");

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

        kpg.initialize(2048);

        KeyPair kp = kpg.generateKeyPair();

        privateKey = (RSAPrivateKey)kp.getPrivate();

        publicKey = (RSAPublicKey)kp.getPublic();

        // Test using a spec with each digest algorithm case

        test(new OAEPParameterSpec("MD5", "MGF1",

                MGF1ParameterSpec.SHA1, PSource.PSpecified.DEFAULT));

        test(new OAEPParameterSpec("SHA1", "MGF1",

                MGF1ParameterSpec.SHA1, PSource.PSpecified.DEFAULT));

        // For default OAEPParameterSpec case (SHA1)

        test(null);

        test(new OAEPParameterSpec("SHA-224", "MGF1",

                MGF1ParameterSpec.SHA1, PSource.PSpecified.DEFAULT));

        test(new OAEPParameterSpec("SHA-256", "MGF1",

                MGF1ParameterSpec.SHA1, PSource.PSpecified.DEFAULT));

        test(new OAEPParameterSpec("SHA-384", "MGF1",

                MGF1ParameterSpec.SHA1, PSource.PSpecified.DEFAULT));

        test(new OAEPParameterSpec("SHA-512", "MGF1",

                MGF1ParameterSpec.SHA1, PSource.PSpecified.DEFAULT));

        if (failed) {

            throw new Exception("Test failed");

        }

    }

    /*

     * Test with one byte, the max bytes, and the max + 1 bytes allowed by

     * the RSA key size and the digest algorithm

     */

    static void test(OAEPParameterSpec spec) throws Exception {

        int dlen = 0;

        String algo;

        // For default OAEPParameterSpec case (SHA1)

        if (spec == null) {

            dlen = 20;

            algo = "Default";

        } else {

            // Use the digest algorith provided in the spec

            algo = spec.getDigestAlgorithm();

            if (algo.equals("MD5")) {

                dlen = 16;

            } else if (algo.equals("SHA1")) {

                dlen = 20;

            } else if (algo.equals("SHA-224")) {

                dlen = 28;

            } else if (algo.equals("SHA-256")) {

                dlen = 32;

            } else if (algo.equals("SHA-384")) {

                dlen = 48;

            } else if (algo.equals("SHA-512")) {

                dlen = 64;

            }

        }

        // OAEP maximum length for a given digest algorith & RSA key length

        int max = ((publicKey.getModulus().bitLength() / 8) - (2 * dlen) - 2);

        // Test with data length of 1

        try {

            testEncryptDecrypt(spec, 1);

        } catch (Exception e) {

            System.out.println(algo + " failed with data length of 1");

            e.printStackTrace();

            failed = true;

        }

        // Test with data length of maximum allowed

        try {

            testEncryptDecrypt(spec, max);

        } catch (Exception e) {

            System.out.println(algo + " failed with data length of " + max);

            e.printStackTrace();

            failed = true;

        }

        // Test with data length of maximum allowed + 1

        try {

            testEncryptDecrypt(spec, max + 1);

            throw new Exception();

        } catch (IllegalBlockSizeException ie) {

                // expected to fail

        } catch (Exception e) {

            System.err.println(algo + " failed with data length of " +

                    (max + 1));

            e.printStackTrace();

            failed = true;

        }

    }

    private static void testEncryptDecrypt(OAEPParameterSpec spec,

            int dataLength) throws Exception {

        System.out.println("Testing OAEP with hash " +

                ((spec != null) ? spec.getDigestAlgorithm() : "Default") +

                ", " + dataLength + " bytes");

        Cipher c = Cipher.getInstance("RSA/ECB/OAEPPadding", cp);

        if (spec != null) {

            c.init(Cipher.ENCRYPT_MODE, publicKey, spec);

        } else {

            c.init(Cipher.ENCRYPT_MODE, publicKey);

        }

        byte[] data = new byte[dataLength];

        byte[] enc = c.doFinal(data);

        if (spec != null) {

            c.init(Cipher.DECRYPT_MODE, privateKey, spec);

        } else {

            c.init(Cipher.DECRYPT_MODE, privateKey);

        }

        byte[] dec = c.doFinal(enc);

        if (Arrays.equals(data, dec) == false) {

            throw new Exception("Data does not match");

        }

    }

}