/*

 * 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.

 */

 */

import java.security.*;

import java.util.*;

public class SignUsingNONEwithRSA {

    private static final List<byte[]> precomputedHashes = Arrays.asList(

        // A MD5 hash

        new byte[] {

            0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x10,

            0x11, 0x12, 0x13, 0x14, 0x15, 0x16

        },

        // A SHA-1 hash

        new byte[] {

            0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x10,

            0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x20

        },

        // A concatenation of SHA-1 and MD5 hashes (used during SSL handshake)

        new byte[] {

            0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x10,

            0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x20,

            0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x30,

            0x31, 0x32, 0x33, 0x34, 0x35, 0x36

        },

        // A SHA-256 hash

        new byte[] {

            0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x10,

            0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x20,

            0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x30,

            0x31, 0x32

        },

        // A SHA-384 hash

        new byte[] {

            0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x10,

            0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x20,

            0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x30,

            0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x40,

            0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48

        },

        // A SHA-512 hash

        new byte[] {

            0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x10,

            0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x20,

            0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x30,

            0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x40,

            0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x50,

            0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x60,

            0x61, 0x62, 0x63, 0x64

        });

    private static List<byte[]> generatedSignatures = new ArrayList<>();

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

        Provider[] providers = Security.getProviders("Signature.NONEwithRSA");

        if (providers == null) {

            System.out.println("No JCE providers support the " +

                "'Signature.NONEwithRSA' algorithm");

            System.out.println("Skipping this test...");

            return;

        } else {

            System.out.println("The following JCE providers support the " +

                "'Signature.NONEwithRSA' algorithm: ");

            for (Provider provider : providers) {

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

            }

        }

    }

    private static KeyPair getKeysFromKeyStore() throws Exception {

        KeyStore ks = KeyStore.getInstance("Windows-MY", "SunMSCAPI");

        ks.load(null, null);

        System.out.println("Loaded keystore: Windows-MY");

        Enumeration<String> e = ks.aliases();

        PrivateKey privateKey = null;

        PublicKey publicKey = null;

        while (e.hasMoreElements()) {

            String alias = e.nextElement();

            if (alias.equals("6578658")) {

                System.out.println("Loaded entry: " + alias);

                privateKey = (PrivateKey) ks.getKey(alias, null);

                publicKey = (PublicKey) ks.getCertificate(alias).getPublicKey();

            }

        }

        if (privateKey == null || publicKey == null) {

            throw new Exception("Cannot load the keys need to run this test");

        }

        return new KeyPair(publicKey, privateKey);

    }

    private static KeyPair generateKeys() throws Exception {

        KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");

        keyGen.initialize(1024, null);

        KeyPair pair = keyGen.generateKeyPair();

        PrivateKey privateKey = pair.getPrivate();

        PublicKey publicKey = pair.getPublic();

        if (privateKey == null || publicKey == null) {

            throw new Exception("Cannot load the keys need to run this test");

        }

        return new KeyPair(publicKey, privateKey);

    }

    private static void signAllUsing(String providerName, PrivateKey privateKey)

            throws Exception {

        Signature sig1 = Signature.getInstance("NONEwithRSA", providerName);

        if (sig1 == null) {

            throw new Exception("'NONEwithRSA' is not supported");

        }

        if (sig1.getProvider() != null) {

            System.out.println("Using NONEwithRSA signer from the " +

                sig1.getProvider().getName() + " JCE provider");

        } else {

            System.out.println(

                "Using NONEwithRSA signer from the internal JCE provider");

        }

        System.out.println("Using key: " + privateKey);

        generatedSignatures.clear();

        for (byte[] hash : precomputedHashes) {

            sig1.initSign(privateKey);

            sig1.update(hash);

            try {

                byte [] sigBytes = sig1.sign();

                System.out.println("\nGenerated RSA signature over a " +

                    hash.length + "-byte hash (signature length: " +

                    sigBytes.length * 8 + " bits)");

                System.out.println(String.format("0x%0" +

                    (sigBytes.length * 2) + "x",

                    new java.math.BigInteger(1, sigBytes)));

                generatedSignatures.add(sigBytes);

            } catch (SignatureException se) {

                System.out.println("Error generating RSA signature: " + se);

            }

        }

    }

    private static void verifyAllUsing(String providerName, PublicKey publicKey)

            throws Exception {

        Signature sig1 = Signature.getInstance("NONEwithRSA", providerName);

        if (sig1.getProvider() != null) {

            System.out.println("\nUsing NONEwithRSA verifier from the " +

                sig1.getProvider().getName() + " JCE provider");

        } else {

            System.out.println(

                "\nUsing NONEwithRSA verifier from the internal JCE provider");

        }

        System.out.println("Using key: " + publicKey);

        int i = 0;

        for (byte[] hash : precomputedHashes) {

            byte[] sigBytes = generatedSignatures.get(i++);

            System.out.println("\nVerifying RSA Signature over a " +

                hash.length + "-byte hash (signature length: " +

                sigBytes.length * 8 + " bits)");

            System.out.println(String.format("0x%0" +

                (sigBytes.length * 2) + "x",

                new java.math.BigInteger(1, sigBytes)));

            sig1.initVerify(publicKey);

            sig1.update(hash);

            if (sig1.verify(sigBytes)) {

                System.out.println("Verify PASSED");

            } else {

                throw new Exception("Verify FAILED");

            }

        }

    }

}