/*

 * 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 8008296

 * @summary Store and retrieve user passwords using PKCS#12 keystore

 */

import java.io.*;

import java.security.*;

import java.util.*;

import javax.crypto.*;

import javax.crypto.spec.*;

/*

 * Store and retrieve passwords protected by a selection of PBE algorithms,

 * using a PKCS#12 keystore.

 */

public class StorePasswords {

    private static final String[] PBE_ALGORITHMS = new String[] {

        "default PBE algorithm",

        "PBEWithMD5AndDES",

        "PBEWithSHA1AndDESede",

        "PBEWithSHA1AndRC2_40",

        "PBEWithSHA1AndRC2_128",

        "PBEWithSHA1AndRC4_40",

        "PBEWithSHA1AndRC4_128",

        "PBEWithHmacSHA1AndAES_128",

        "PBEWithHmacSHA224AndAES_128",

        "PBEWithHmacSHA256AndAES_128",

        "PBEWithHmacSHA384AndAES_128",

        "PBEWithHmacSHA512AndAES_128",

        "PBEWithHmacSHA1AndAES_256",

        "PBEWithHmacSHA224AndAES_256",

        "PBEWithHmacSHA256AndAES_256",

        "PBEWithHmacSHA384AndAES_256",

        "PBEWithHmacSHA512AndAES_256"

    };

    private static final String KEYSTORE = "mykeystore.p12";

    private static final char[] KEYSTORE_PWD = "changeit".toCharArray();

    private static final char[] ENTRY_PWD = "protectit".toCharArray();

    private static final char[] USER_PWD = "hello1".toCharArray();

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

        new File(KEYSTORE).delete();

        int storeCount = store();

        int recoverCount = recover();

        if (recoverCount != storeCount) {

            throw new Exception("Stored " + storeCount + " user passwords, " +

                "recovered " + recoverCount + " user passwords");

        }

        System.out.println("\nStored " + storeCount + " user passwords, " +

            "recovered " + recoverCount + " user passwords");

        new File(KEYSTORE).delete();

    }

    private static int store() throws Exception {

        int count = 0;

        // Load an empty PKCS#12 keystore

        KeyStore keystore = KeyStore.getInstance("PKCS12");

        System.out.println("\nLoading PKCS#12 keystore...");

        keystore.load(null, null);

        // Derive a PBE key from the password

        PBEKeySpec keySpec = new PBEKeySpec(USER_PWD);

        SecretKeyFactory factory = SecretKeyFactory.getInstance("PBE");

        SecretKey key = factory.generateSecret(keySpec);

        PBEParameterSpec specWithEightByteSalt =

            new PBEParameterSpec("NaClNaCl".getBytes(), 1024);

        // Store the user password in a keystore entry (for each algorithm)

        for (String algorithm : PBE_ALGORITHMS) {

            try {

                System.out.println("Storing user password '" +

                    new String(USER_PWD) + "' (protected by " + algorithm +

                    ")");

                if (algorithm.equals("default PBE algorithm")) {

                     keystore.setKeyEntry(

                         "this entry is protected by " + algorithm, key,

                         ENTRY_PWD, null);

                } else {

                    keystore.setEntry(

                        "this entry is protected by " + algorithm,

                        new KeyStore.SecretKeyEntry(key),

                        new KeyStore.PasswordProtection(ENTRY_PWD, algorithm,

                            null));

                }

                count++;

            } catch (KeyStoreException e) {

                Throwable inner = e.getCause();

                if (inner instanceof UnrecoverableKeyException) {

                    Throwable inner2 = inner.getCause();

                    if (inner2 instanceof InvalidAlgorithmParameterException) {

                        System.out.println("...re-trying due to: " +

                            inner2.getMessage());

                        // Some PBE algorithms demand an 8-byte salt

                        keystore.setEntry(

                            "this entry is protected by " + algorithm,

                            new KeyStore.SecretKeyEntry(key),

                            new KeyStore.PasswordProtection(ENTRY_PWD,

                                algorithm, specWithEightByteSalt));

                        count++;

                    } else if (inner2  instanceof InvalidKeyException) {

                        System.out.println("...skipping due to: " +

                            inner2.getMessage());

                        // Unsupported crypto keysize

                        continue;

                    }

                } else {

                    throw e;

                }

            }

        }

        // Store the PKCS#12 keystore

        System.out.println("Storing PKCS#12 keystore to: " + KEYSTORE);

        try (FileOutputStream out = new FileOutputStream(KEYSTORE)) {

            keystore.store(out, KEYSTORE_PWD);

        }

        return count;

    }

    private static int recover() throws Exception {

        int count = 0;

        // Load the PKCS#12 keystore

        KeyStore keystore = KeyStore.getInstance("PKCS12");

        System.out.println("\nLoading PKCS#12 keystore from: " + KEYSTORE);

        try (FileInputStream in = new FileInputStream(KEYSTORE)) {

            keystore.load(in, KEYSTORE_PWD);

        }

        SecretKey key;

        SecretKeyFactory factory;

        PBEKeySpec keySpec;

        // Retrieve each user password from the keystore

        for (String algorithm : PBE_ALGORITHMS) {

            key = (SecretKey) keystore.getKey("this entry is protected by " +

                algorithm, ENTRY_PWD);

            if (key != null) {

                count++;

                factory = SecretKeyFactory.getInstance(key.getAlgorithm());

                keySpec =

                    (PBEKeySpec) factory.getKeySpec(key, PBEKeySpec.class);

                char[] pwd = keySpec.getPassword();

                System.out.println("Recovered user password '" +

                     new String(pwd) + "' (protected by " + algorithm + ")");

                if (!Arrays.equals(USER_PWD, pwd)) {

                    throw new Exception("Failed to recover the user password " +

                        "protected by " + algorithm);

                }

            }

        }

        return count;

    }

}