/*

 * Copyright (c) 2015, 2018, 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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

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 */

package sun.security.ssl;

import java.io.IOException;

import java.nio.ByteBuffer;

import java.text.MessageFormat;

import java.util.Locale;

import sun.security.ssl.ClientHello.ClientHelloMessage;

import sun.security.ssl.SSLHandshake.HandshakeMessage;

/**

 * Pack of the HelloVerifyRequest handshake message.

 */

final class HelloVerifyRequest {

    static final SSLConsumer handshakeConsumer =

            new HelloVerifyRequestConsumer();

    static final HandshakeProducer handshakeProducer =

            new HelloVerifyRequestProducer();

    /**

     * The HelloVerifyRequest handshake message [RFC 6347].

     */

    static final class HelloVerifyRequestMessage extends HandshakeMessage {

        final int                   serverVersion;

        final byte[]                cookie;

        HelloVerifyRequestMessage(HandshakeContext context,

                HandshakeMessage message) throws IOException {

            super(context);

            // This happens in server side only.

            ServerHandshakeContext shc =

                    (ServerHandshakeContext)context;

            ClientHelloMessage clientHello = (ClientHelloMessage)message;

            HelloCookieManager hcMgr =

                shc.sslContext.getHelloCookieManager(ProtocolVersion.DTLS10);

            this.serverVersion = shc.clientHelloVersion;

            this.cookie = hcMgr.createCookie(shc, clientHello);

        }

        HelloVerifyRequestMessage(HandshakeContext context,

                ByteBuffer m) throws IOException {

            super(context);

            // This happens in client side only.

            ClientHandshakeContext chc = (ClientHandshakeContext)context;

            //  struct {

            //      ProtocolVersion server_version;

            //      opaque cookie<0..2^8-1>;

            //  } HelloVerifyRequest;

            if (m.remaining() < 3) {

                chc.conContext.fatal(Alert.ILLEGAL_PARAMETER,

                    "Invalid HelloVerifyRequest: no sufficient data");

            }

            byte major = m.get();

            byte minor = m.get();

            this.serverVersion = ((major & 0xFF) << 8) | (minor & 0xFF);

            this.cookie = Record.getBytes8(m);

        }

        @Override

        public SSLHandshake handshakeType() {

            return SSLHandshake.HELLO_VERIFY_REQUEST;

        }

        @Override

        public int messageLength() {

            return 2 + cookie.length;   // 2: the length of protocol version

        }

        @Override

        public void send(HandshakeOutStream hos) throws IOException {

            hos.putInt8((byte)((serverVersion >>> 8) & 0xFF));

            hos.putInt8((byte)(serverVersion & 0xFF));

            hos.putBytes8(cookie);

        }

        @Override

        public String toString() {

            MessageFormat messageFormat = new MessageFormat(

                "\"HelloVerifyRequest\": '{'\n" +

                "  \"server version\"      : \"{0}\",\n" +

                "  \"cookie\"              : \"{1}\",\n" +

                "'}'",

                Locale.ENGLISH);

            Object[] messageFields = {

                ProtocolVersion.nameOf(serverVersion),

                Utilities.toHexString(cookie),

            };

            return messageFormat.format(messageFields);

        }

    }

    /**

     * The "HelloVerifyRequest" handshake message producer.

     */

    private static final

            class HelloVerifyRequestProducer implements HandshakeProducer {

        // Prevent instantiation of this class.

        private HelloVerifyRequestProducer() {

            // blank

        }

        @Override

        public byte[] produce(ConnectionContext context,

                HandshakeMessage message) throws IOException {

            // The producing happens in server side only.

            ServerHandshakeContext shc = (ServerHandshakeContext)context;

            // clean up this producer

            shc.handshakeProducers.remove(SSLHandshake.HELLO_VERIFY_REQUEST.id);

            HelloVerifyRequestMessage hvrm =

                    new HelloVerifyRequestMessage(shc, message);

            if (SSLLogger.isOn && SSLLogger.isOn("ssl,handshake")) {

                SSLLogger.fine(

                        "Produced HelloVerifyRequest handshake message", hvrm);

            }

            // Output the handshake message.

            hvrm.write(shc.handshakeOutput);

            shc.handshakeOutput.flush();

            // update the context

            // TODO: stateless, clean up the handshake context?

            shc.handshakeHash.finish();     // forgot about the handshake hash

            shc.handshakeExtensions.clear();

            // What's the expected response?

            shc.handshakeConsumers.put(

                    SSLHandshake.CLIENT_HELLO.id, SSLHandshake.CLIENT_HELLO);

            // The handshake message has been delivered.

            return null;

        }

    }

    /**

     * The "HelloVerifyRequest" handshake message consumer.

     */

    private static final class HelloVerifyRequestConsumer

            implements SSLConsumer {

        // Prevent instantiation of this class.

        private HelloVerifyRequestConsumer() {

            // blank

        }

        @Override

        public void consume(ConnectionContext context,

                ByteBuffer message) throws IOException {

            // The consuming happens in client side only.

            ClientHandshakeContext chc = (ClientHandshakeContext)context;

            // clean up this consumer

            chc.handshakeConsumers.remove(SSLHandshake.HELLO_VERIFY_REQUEST.id);

            if (!chc.handshakeConsumers.isEmpty()) {

                chc.handshakeConsumers.remove(SSLHandshake.SERVER_HELLO.id);

            }

            if (!chc.handshakeConsumers.isEmpty()) {

                chc.conContext.fatal(Alert.UNEXPECTED_MESSAGE,

                        "No more message expected before " +

                        "HelloVerifyRequest is processed");

            }

            // Refresh handshake hash.

            chc.handshakeHash.finish();     // forgot about the handshake hash

            HelloVerifyRequestMessage hvrm =

                    new HelloVerifyRequestMessage(chc, message);

            if (SSLLogger.isOn && SSLLogger.isOn("ssl,handshake")) {

                SSLLogger.fine(

                        "Consuming HelloVerifyRequest handshake message", hvrm);

            }

            // Note that HelloVerifyRequest.server_version is used solely to

            // indicate packet formatting, and not as part of version

            // negotiation.  Need not to check version values match for

            // HelloVerifyRequest message.

            chc.initialClientHelloMsg.setHelloCookie(hvrm.cookie);

            //

            // produce response handshake message

            //

            SSLHandshake.CLIENT_HELLO.produce(context, hvrm);

        }

    }

}