/*

 * 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

 * questions.

 */

package sun.security.ssl;

import java.io.IOException;

import java.nio.ByteBuffer;

import sun.security.ssl.SSLHandshake.HandshakeMessage;

/**

 * Pack of the HelloRequest handshake message.

 */

final class HelloRequest {

    static final SSLProducer kickstartProducer =

        new HelloRequestKickstartProducer();

    static final SSLConsumer handshakeConsumer =

        new HelloRequestConsumer();

    static final HandshakeProducer handshakeProducer =

        new HelloRequestProducer();

    /**

     * The HelloRequest handshake message.

     *

     * [RFC 5246] The HelloRequest message MAY be sent by the server at any

     * time.  HelloRequest is a simple notification that the client should

     * begin the negotiation process anew.

     *

     *      struct { } HelloRequest;

     */

    static final class HelloRequestMessage extends HandshakeMessage {

        HelloRequestMessage(HandshakeContext handshakeContext) {

            super(handshakeContext);

        }

        HelloRequestMessage(HandshakeContext handshakeContext,

                ByteBuffer m) throws IOException {

            super(handshakeContext);

            if (m.hasRemaining()) {

                handshakeContext.conContext.fatal(Alert.ILLEGAL_PARAMETER,

                    "Error parsing HelloRequest message: not empty");

            }

        }

        @Override

        public SSLHandshake handshakeType() {

            return SSLHandshake.HELLO_REQUEST;

        }

        @Override

        public int messageLength() {

            return 0;

        }

        @Override

        public void send(HandshakeOutStream s) throws IOException {

            // empty, nothing to send

        }

        @Override

        public String toString() {

            return "<empty>";

        }

    }

    /**

     * The "HelloRequest" handshake message kick start producer.

     */

    private static final

            class HelloRequestKickstartProducer implements SSLProducer {

        // Prevent instantiation of this class.

        private HelloRequestKickstartProducer() {

            // blank

        }

        @Override

        public byte[] produce(ConnectionContext context) throws IOException {

            // The producing happens in server side only.

            ServerHandshakeContext shc = (ServerHandshakeContext)context;

            HelloRequestMessage hrm = new HelloRequestMessage(shc);

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

                SSLLogger.fine("Produced HelloRequest handshake message", hrm);

            }

            // Output the handshake message.

            hrm.write(shc.handshakeOutput);

            shc.handshakeOutput.flush();

            // update the context

            // What's the expected response?

            shc.handshakeConsumers.put(

                    SSLHandshake.CLIENT_HELLO.id, SSLHandshake.CLIENT_HELLO);

            // The handshake message has been delivered.

            return null;

        }

    }

    /**

     * The "HelloRequest" handshake message producer.

     */

    private static final class HelloRequestProducer

            implements HandshakeProducer {

        // Prevent instantiation of this class.

        private HelloRequestProducer() {

            // blank

        }

        @Override

        public byte[] produce(ConnectionContext context,

                HandshakeMessage message) throws IOException {

            // The producing happens in server side only.

            ServerHandshakeContext shc = (ServerHandshakeContext)context;

            HelloRequestMessage hrm = new HelloRequestMessage(shc);

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

                SSLLogger.fine("Produced HelloRequest handshake message", hrm);

            }

            // Output the handshake message.

            hrm.write(shc.handshakeOutput);

            shc.handshakeOutput.flush();

            // update the context

            // What's the expected response?

            shc.handshakeConsumers.put(

                    SSLHandshake.CLIENT_HELLO.id, SSLHandshake.CLIENT_HELLO);

            // The handshake message has been delivered.

            return null;

        }

    }

    /**

     * The "HelloRequest" handshake message consumer.

     */

    private static final class HelloRequestConsumer

            implements SSLConsumer {

        // Prevent instantiation of this class.

        private HelloRequestConsumer() {

            // blank

        }

        @Override

        public void consume(ConnectionContext context,

                ByteBuffer message) throws IOException {

            // The consuming happens in client side only.

            ClientHandshakeContext chc = (ClientHandshakeContext)context;

            // For TLS 1.2 and prior versions, the HelloRequest message MAY

            // be sent by the server at any time.  Please don't clean up this

            // handshake consumer.

            HelloRequestMessage hrm = new HelloRequestMessage(chc, message);

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

                SSLLogger.fine(

                        "Consuming HelloRequest handshake message", hrm);

            }

            if (!chc.kickstartMessageDelivered) {

                if (!chc.conContext.secureRenegotiation &&

                        !HandshakeContext.allowUnsafeRenegotiation) {

                    chc.conContext.fatal(Alert.HANDSHAKE_FAILURE,

                            "Unsafe renegotiation is not allowed");

                }

                if (!chc.conContext.secureRenegotiation) {

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

                        SSLLogger.warning(

                                "Continue with insecure renegotiation");

                    }

                }

                // update the responders

                chc.handshakeProducers.put(

                        SSLHandshake.CLIENT_HELLO.id,

                        SSLHandshake.CLIENT_HELLO);

                //

                // produce response handshake message

                //

                SSLHandshake.CLIENT_HELLO.produce(context, hrm);

            } else {

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

                    SSLLogger.fine(

                            "Ingore HelloRequest, handshaking is in progress");

                }

            }

        }

    }

}