/*

 * Copyright (c) 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 java.text.MessageFormat;

import java.util.Locale;

import javax.net.ssl.SSLProtocolException;

import sun.security.ssl.ClientHello.ClientHelloMessage;

import sun.security.ssl.SSLExtension.ExtensionConsumer;

import sun.security.ssl.SSLHandshake.HandshakeMessage;

import sun.security.ssl.SSLExtension.SSLExtensionSpec;

import sun.security.ssl.ServerHello.ServerHelloMessage;

import sun.security.util.HexDumpEncoder;

public class CookieExtension {

    static final HandshakeProducer chNetworkProducer =

            new CHCookieProducer();

    static final ExtensionConsumer chOnLoadConsumer =

            new CHCookieConsumer();

    static final HandshakeConsumer chOnTradeConsumer =

            new CHCookieUpdate();

    static final HandshakeProducer hrrNetworkProducer =

            new HRRCookieProducer();

    static final ExtensionConsumer hrrOnLoadConsumer =

            new HRRCookieConsumer();

    static final HandshakeProducer hrrNetworkReproducer =

            new HRRCookieReproducer();

    static final CookieStringizer cookieStringizer =

            new CookieStringizer();

    /**

     * The "cookie" extension.

     */

    static class CookieSpec implements SSLExtensionSpec {

        final byte[] cookie;

        private CookieSpec(ByteBuffer m) throws IOException {

            // opaque cookie<1..2^16-1>;

            if (m.remaining() < 3) {

                throw new SSLProtocolException(

                    "Invalid cookie extension: insufficient data");

            }

            this.cookie = Record.getBytes16(m);

        }

        @Override

        public String toString() {

            MessageFormat messageFormat = new MessageFormat(

                    "\"cookie\": '{'\n" +

                    "{0}\n" +

                    "'}',", Locale.ENGLISH);

            HexDumpEncoder hexEncoder = new HexDumpEncoder();

            Object[] messageFields = {

                Utilities.indent(hexEncoder.encode(cookie))

            };

            return messageFormat.format(messageFields);

        }

    }

    private static final class CookieStringizer implements SSLStringizer {

        @Override

        public String toString(ByteBuffer buffer) {

            try {

                return (new CookieSpec(buffer)).toString();

            } catch (IOException ioe) {

                // For debug logging only, so please swallow exceptions.

                return ioe.getMessage();

            }

        }

    }

    private static final

            class CHCookieProducer implements HandshakeProducer {

        // Prevent instantiation of this class.

        private CHCookieProducer() {

            // blank

        }

        @Override

        public byte[] produce(ConnectionContext context,

                HandshakeMessage message) throws IOException {

            ClientHandshakeContext chc = (ClientHandshakeContext) context;

            // Is it a supported and enabled extension?

            if (!chc.sslConfig.isAvailable(SSLExtension.CH_COOKIE)) {

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

                    SSLLogger.fine(

                            "Ignore unavailable cookie extension");

                }

                return null;

            }

            // response to an HelloRetryRequest cookie

            CookieSpec spec = (CookieSpec)chc.handshakeExtensions.get(

                    SSLExtension.HRR_COOKIE);

            if (spec != null &&

                    spec.cookie != null && spec.cookie.length != 0) {

                byte[] extData = new byte[spec.cookie.length + 2];

                ByteBuffer m = ByteBuffer.wrap(extData);

                Record.putBytes16(m, spec.cookie);

                return extData;

            }

            return null;

        }

    }

    private static final

            class CHCookieConsumer implements ExtensionConsumer {

        // Prevent instantiation of this class.

        private CHCookieConsumer() {

            // blank

        }

        @Override

        public void consume(ConnectionContext context,

            HandshakeMessage message, ByteBuffer buffer) throws IOException {

            // The consuming happens in server side only.

            ServerHandshakeContext shc = (ServerHandshakeContext)context;

            // Is it a supported and enabled extension?

            if (!shc.sslConfig.isAvailable(SSLExtension.CH_COOKIE)) {

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

                    SSLLogger.fine(

                            "Ignore unavailable cookie extension");

                }

                return;     // ignore the extension

            }

            CookieSpec spec;

            try {

                spec = new CookieSpec(buffer);

            } catch (IOException ioe) {

                throw shc.conContext.fatal(Alert.UNEXPECTED_MESSAGE, ioe);

            }

            shc.handshakeExtensions.put(SSLExtension.CH_COOKIE, spec);

            // No impact on session resumption.

            //

            // Note that the protocol version negotiation happens before the

            // session resumption negotiation.  And the session resumption

            // negotiation depends on the negotiated protocol version.

        }

    }

    private static final

            class CHCookieUpdate implements HandshakeConsumer {

        // Prevent instantiation of this class.

        private CHCookieUpdate() {

            // blank

        }

        @Override

        public void consume(ConnectionContext context,

                HandshakeMessage message) throws IOException {

            // The consuming happens in server side only.

            ServerHandshakeContext shc = (ServerHandshakeContext)context;

            ClientHelloMessage clientHello = (ClientHelloMessage)message;

            CookieSpec spec = (CookieSpec)

                    shc.handshakeExtensions.get(SSLExtension.CH_COOKIE);

            if (spec == null) {

                // Ignore, no "cookie" extension requested.

                return;

            }

            HelloCookieManager hcm =

                shc.sslContext.getHelloCookieManager(shc.negotiatedProtocol);

            if (!hcm.isCookieValid(shc, clientHello, spec.cookie)) {

                throw shc.conContext.fatal(Alert.UNEXPECTED_MESSAGE,

                        "unrecognized cookie");

            }

        }

    }

    private static final

            class HRRCookieProducer implements HandshakeProducer {

        // Prevent instantiation of this class.

        private HRRCookieProducer() {

            // blank

        }

        @Override

        public byte[] produce(ConnectionContext context,

                HandshakeMessage message) throws IOException {

            // The producing happens in server side only.

            ServerHandshakeContext shc = (ServerHandshakeContext)context;

            ServerHelloMessage hrrm = (ServerHelloMessage)message;

            // Is it a supported and enabled extension?

            if (!shc.sslConfig.isAvailable(SSLExtension.HRR_COOKIE)) {

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

                    SSLLogger.fine(

                            "Ignore unavailable cookie extension");

                }

                return null;

            }

            HelloCookieManager hcm =

                shc.sslContext.getHelloCookieManager(shc.negotiatedProtocol);

            byte[] cookie = hcm.createCookie(shc, hrrm.clientHello);

            byte[] extData = new byte[cookie.length + 2];

            ByteBuffer m = ByteBuffer.wrap(extData);

            Record.putBytes16(m, cookie);

            return extData;

        }

    }

    private static final

            class HRRCookieConsumer implements ExtensionConsumer {

        // Prevent instantiation of this class.

        private HRRCookieConsumer() {

            // blank

        }

        @Override

        public void consume(ConnectionContext context,

            HandshakeMessage message, ByteBuffer buffer) throws IOException {

            // The consuming happens in client side only.

            ClientHandshakeContext chc = (ClientHandshakeContext)context;

            // Is it a supported and enabled extension?

            if (!chc.sslConfig.isAvailable(SSLExtension.HRR_COOKIE)) {

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

                    SSLLogger.fine(

                            "Ignore unavailable cookie extension");

                }

                return;     // ignore the extension

            }

            CookieSpec spec;

            try {

                spec = new CookieSpec(buffer);

            } catch (IOException ioe) {

                throw chc.conContext.fatal(Alert.UNEXPECTED_MESSAGE, ioe);

            }

            chc.handshakeExtensions.put(SSLExtension.HRR_COOKIE, spec);

        }

    }

    private static final

            class HRRCookieReproducer implements HandshakeProducer {

        // Prevent instantiation of this class.

        private HRRCookieReproducer() {

            // blank

        }

        @Override

        public byte[] produce(ConnectionContext context,

                HandshakeMessage message) throws IOException {

            // The producing happens in server side only.

            ServerHandshakeContext shc = (ServerHandshakeContext) context;

            // Is it a supported and enabled extension?

            if (!shc.sslConfig.isAvailable(SSLExtension.HRR_COOKIE)) {

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

                    SSLLogger.fine(

                            "Ignore unavailable cookie extension");

                }

                return null;

            }

            // copy of the ClientHello cookie

            CookieSpec spec = (CookieSpec)shc.handshakeExtensions.get(

                    SSLExtension.CH_COOKIE);

            if (spec != null &&

                    spec.cookie != null && spec.cookie.length != 0) {

                byte[] extData = new byte[spec.cookie.length + 2];

                ByteBuffer m = ByteBuffer.wrap(extData);

                Record.putBytes16(m, spec.cookie);

                return extData;

            }

            return null;

        }

    }

}