/*

 * 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

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 */

package sun.security.ssl;

import java.io.IOException;

import java.nio.ByteBuffer;

import java.text.MessageFormat;

import java.util.Arrays;

import java.util.Locale;

import javax.net.ssl.SSLProtocolException;

import sun.security.ssl.ClientHello.ClientHelloMessage;

import static sun.security.ssl.SSLExtension.CH_RENEGOTIATION_INFO;

import sun.security.ssl.SSLExtension.ExtensionConsumer;

import static sun.security.ssl.SSLExtension.SH_RENEGOTIATION_INFO;

import sun.security.ssl.SSLExtension.SSLExtensionSpec;

import sun.security.ssl.SSLHandshake.HandshakeMessage;

/**

 * Pack of the "renegotiation_info" extensions [RFC 5746].

 */

final class RenegoInfoExtension {

    static final HandshakeProducer chNetworkProducer =

            new CHRenegotiationInfoProducer();

    static final ExtensionConsumer chOnLoadConsumer =

            new CHRenegotiationInfoConsumer();

    static final HandshakeAbsence chOnLoadAbsence =

            new CHRenegotiationInfoAbsence();

    static final HandshakeProducer shNetworkProducer =

            new SHRenegotiationInfoProducer();

    static final ExtensionConsumer shOnLoadConsumer =

            new SHRenegotiationInfoConsumer();

    static final HandshakeAbsence shOnLoadAbsence =

            new SHRenegotiationInfoAbsence();

    /**

     * The "renegotiation_info" extension.

     */

    static final class RenegotiationInfoSpec implements SSLExtensionSpec {

        // A nominal object that does not holding any real renegotiation info.

        static final RenegotiationInfoSpec NOMINAL =

                new RenegotiationInfoSpec(new byte[0]);

        private final byte[] renegotiatedConnection;

        private RenegotiationInfoSpec(byte[] renegotiatedConnection) {

            this.renegotiatedConnection = Arrays.copyOf(

                    renegotiatedConnection, renegotiatedConnection.length);

        }

        private RenegotiationInfoSpec(ByteBuffer m) throws IOException {

            // Parse the extension.

            if (!m.hasRemaining() || m.remaining() < 1) {

                throw new SSLProtocolException(

                    "Invalid renegotiation_info extension data: " +

                    "insufficient data");

            }

            this.renegotiatedConnection = Record.getBytes8(m);

        }

        @Override

        public String toString() {

            MessageFormat messageFormat = new MessageFormat(

                "\"renegotiated connection\": '['{0}']'", Locale.ENGLISH);

            if (renegotiatedConnection.length == 0) {

                Object[] messageFields = {

                        "<no renegotiated connection>"

                    };

                return messageFormat.format(messageFields);

            } else {

                Object[] messageFields = {

                        Utilities.toHexString(renegotiatedConnection)

                    };

                return messageFormat.format(messageFields);

            }

        }

    }

    private static final

        @Override

        public String toString(ByteBuffer buffer) {

            try {

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

            } catch (IOException ioe) {

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

                return ioe.getMessage();

            }

        }

    }

    /**

     * Network data producer of a "renegotiation_info" extension in

     * the ClientHello handshake message.

     */

    private static final

            class CHRenegotiationInfoProducer implements HandshakeProducer {

        // Prevent instantiation of this class.

        private CHRenegotiationInfoProducer() {

            // blank

        }

        @Override

        public byte[] produce(ConnectionContext context,

                HandshakeMessage message) throws IOException {

            // The producing happens in client side only.

            ClientHandshakeContext chc = (ClientHandshakeContext)context;

            // Is it a supported and enabled extension?

            if (!chc.sslConfig.isAvailable(CH_RENEGOTIATION_INFO)) {

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

                    SSLLogger.fine(

                            "Ignore unavailable renegotiation_info extension");

                }

                return null;

            }

            if (!chc.conContext.isNegotiated) {

                if (chc.activeCipherSuites.contains(

                        CipherSuite.TLS_EMPTY_RENEGOTIATION_INFO_SCSV)) {

                    // Using the the TLS_EMPTY_RENEGOTIATION_INFO_SCSV instead.

                    return null;

                }

                // initial handshaking.

                //

                // If this is the initial handshake for a connection, then the

                // "renegotiated_connection" field is of zero length in both

                // the ClientHello and the ServerHello. [RFC 5746]

                byte[] extData = new byte[] { 0x00 };

                chc.handshakeExtensions.put(

                        CH_RENEGOTIATION_INFO, RenegotiationInfoSpec.NOMINAL);

                return extData;

            } else if (chc.conContext.secureRenegotiation) {

                // secure renegotiation

                //

                // For ClientHello handshake message in renegotiation, this

                // field contains the "client_verify_data".

                byte[] extData =

                        new byte[chc.conContext.clientVerifyData.length + 1];

                ByteBuffer m = ByteBuffer.wrap(extData);

                Record.putBytes8(m, chc.conContext.clientVerifyData);

                // The conContext.clientVerifyData will be used for further

                // processing, so it does not matter to save whatever in the

                // RenegotiationInfoSpec object.

                chc.handshakeExtensions.put(

                        CH_RENEGOTIATION_INFO, RenegotiationInfoSpec.NOMINAL);

                return extData;

            } else {    // not secure renegotiation

                if (HandshakeContext.allowUnsafeRenegotiation) {

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

                        SSLLogger.warning("Using insecure renegotiation");

                    }

                    return null;

                } else {

                    // terminate the session.

                    chc.conContext.fatal(Alert.HANDSHAKE_FAILURE,

                            "insecure renegotiation is not allowed");

                }

            }

            return null;

        }

    }

    /**

     * Network data producer of a "renegotiation_info" extension in

     * the ServerHello handshake message.

     */

    private static final

            class CHRenegotiationInfoConsumer implements ExtensionConsumer {

        // Prevent instantiation of this class.

        private CHRenegotiationInfoConsumer() {

            // 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(CH_RENEGOTIATION_INFO)) {

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

                    SSLLogger.fine("Ignore unavailable extension: " +

                            CH_RENEGOTIATION_INFO.name);

                }

                return;     // ignore the extension

            }

            // Parse the extension.

            RenegotiationInfoSpec spec;

            try {

                spec = new RenegotiationInfoSpec(buffer);

            } catch (IOException ioe) {

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

                return;     // fatal() always throws, make the compiler happy.

            }

            if (!shc.conContext.isNegotiated) {

                // initial handshaking.

                if (spec.renegotiatedConnection.length != 0) {

                    shc.conContext.fatal(Alert.UNEXPECTED_MESSAGE,

                        "Invalid renegotiation_info extension data: not empty");

                }

                shc.conContext.secureRenegotiation = true;

            } else {

                if (!shc.conContext.secureRenegotiation) {

                    // Unexpected RI extension for insecure renegotiation,

                    // abort the handshake with a fatal handshake_failure alert.

                    shc.conContext.fatal(Alert.HANDSHAKE_FAILURE,

                            "The renegotiation_info is present in a insecure " +

                            "renegotiation");

                } else {

                    // verify the client_verify_data value

                    if (!Arrays.equals(shc.conContext.clientVerifyData,

                            spec.renegotiatedConnection)) {

                        shc.conContext.fatal(Alert.UNEXPECTED_MESSAGE,

                            "Invalid renegotiation_info extension data: " +

                            "incorrect verify data in ClientHello");

                    }

                }

            }

            // Update the context.

            //

            // The conContext.clientVerifyData will be used for further

            // processing, so it does not matter to save whatever in the

            // RenegotiationInfoSpec object.

            shc.handshakeExtensions.put(

                    CH_RENEGOTIATION_INFO, RenegotiationInfoSpec.NOMINAL);

            // No impact on session resumption.

        }

    }

    /**

     * The absence processing if a "renegotiation_info" extension is

     * not present in the ClientHello handshake message.

     */

    private static final

            class CHRenegotiationInfoAbsence implements HandshakeAbsence {

        @Override

        public void absent(ConnectionContext context,

                HandshakeMessage message) throws IOException {

            // The producing happens in server side only.

            ServerHandshakeContext shc = (ServerHandshakeContext)context;

            ClientHelloMessage clientHello = (ClientHelloMessage)message;

            if (!shc.conContext.isNegotiated) {

                // initial handshaking.

                for (int id : clientHello.cipherSuiteIds) {

                    if (id ==

                            CipherSuite.TLS_EMPTY_RENEGOTIATION_INFO_SCSV.id) {

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

                            SSLLogger.finest(

                                "Safe renegotiation, using the SCSV signgling");

                        }

                        shc.conContext.secureRenegotiation = true;

                        return;

                    }

                }

                if (!HandshakeContext.allowLegacyHelloMessages) {

                    shc.conContext.fatal(Alert.HANDSHAKE_FAILURE,

                        "Failed to negotiate the use of secure renegotiation");

                }   // otherwise, allow legacy hello message

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

                    SSLLogger.warning("Warning: No renegotiation " +

                        "indication in ClientHello, allow legacy ClientHello");

                }

                shc.conContext.secureRenegotiation = false;

            } else if (shc.conContext.secureRenegotiation) {

                // Require secure renegotiation, terminate the connection.

                shc.conContext.fatal(Alert.HANDSHAKE_FAILURE,

                        "Inconsistent secure renegotiation indication");

            } else {    // renegotiation, not secure

                if (HandshakeContext.allowUnsafeRenegotiation) {

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

                        SSLLogger.warning("Using insecure renegotiation");

                    }

                } else {

                    // Unsafe renegotiation should have been aborted in

                    // ealier processes.

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

                        SSLLogger.fine("Terminate insecure renegotiation");

                    }

                    shc.conContext.fatal(Alert.HANDSHAKE_FAILURE,

                        "Unsafe renegotiation is not allowed");

                }

            }

        }

    }

    /**

     * Network data producer of a "renegotiation_info" extension in

     * the ServerHello handshake message.

     */

    private static final

            class SHRenegotiationInfoProducer implements HandshakeProducer {

        // Prevent instantiation of this class.

        private SHRenegotiationInfoProducer() {

            // blank

        }

        @Override

        public byte[] produce(ConnectionContext context,

                HandshakeMessage message) throws IOException {

            // The producing happens in server side only.

            ServerHandshakeContext shc = (ServerHandshakeContext)context;

            // In response to "renegotiation_info" extension request only.

            RenegotiationInfoSpec requestedSpec = (RenegotiationInfoSpec)

                    shc.handshakeExtensions.get(CH_RENEGOTIATION_INFO);

            if (requestedSpec == null && !shc.conContext.secureRenegotiation) {

                // Ignore, no renegotiation_info extension or SCSV signgling

                // requested.

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

                    SSLLogger.finest(

                        "Ignore unavailable renegotiation_info extension");

                }

                return null;        // ignore the extension

            }

            if (!shc.conContext.secureRenegotiation) {

                // Ignore, no secure renegotiation is negotiated.

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

                    SSLLogger.finest(

                        "No secure renegotiation has been negotiated");

                }

                return null;        // ignore the extension

            }

            if (!shc.conContext.isNegotiated) {

                // initial handshaking.

                //

                // If this is the initial handshake for a connection, then the

                // "renegotiated_connection" field is of zero length in both

                // the ClientHello and the ServerHello. [RFC 5746]

                byte[] extData = new byte[] { 0x00 };

                // The conContext.client/serverVerifyData will be used for

                // further processing, so it does not matter to save whatever

                // in the RenegotiationInfoSpec object.

                shc.handshakeExtensions.put(

                        SH_RENEGOTIATION_INFO, RenegotiationInfoSpec.NOMINAL);

                return extData;

            } else {

                // secure renegotiation

                //

                // For secure renegotiation, the server MUST include a

                // "renegotiation_info" extension containing the saved

                // client_verify_data and server_verify_data in the ServerHello.

                int infoLen = shc.conContext.clientVerifyData.length +

                              shc.conContext.serverVerifyData.length;

                byte[] extData = new byte[infoLen + 1];

                ByteBuffer m = ByteBuffer.wrap(extData);

                Record.putInt8(m, infoLen);

                m.put(shc.conContext.clientVerifyData);

                m.put(shc.conContext.serverVerifyData);

                // The conContext.client/serverVerifyData will be used for

                // further processing, so it does not matter to save whatever

                // in the RenegotiationInfoSpec object.

                shc.handshakeExtensions.put(

                        SH_RENEGOTIATION_INFO, RenegotiationInfoSpec.NOMINAL);

                return extData;

            }

        }

    }

    /**

     * Network data consumer of a "renegotiation_info" extension in

     * the ServerHello handshake message.

     */

    private static final

            class SHRenegotiationInfoConsumer implements ExtensionConsumer {

        // Prevent instantiation of this class.

        private SHRenegotiationInfoConsumer() {

            // blank

        }

        @Override

        public void consume(ConnectionContext context,

            HandshakeMessage message, ByteBuffer buffer) throws IOException {

            // The producing happens in client side only.

            ClientHandshakeContext chc = (ClientHandshakeContext)context;

            // In response to the client renegotiation_info extension request

            // or SCSV signling, which is mandatory for ClientHello message.

            RenegotiationInfoSpec requestedSpec = (RenegotiationInfoSpec)

                    chc.handshakeExtensions.get(CH_RENEGOTIATION_INFO);

            if (requestedSpec == null &&

                    !chc.activeCipherSuites.contains(

                            CipherSuite.TLS_EMPTY_RENEGOTIATION_INFO_SCSV)) {

                chc.conContext.fatal(Alert.INTERNAL_ERROR,

                    "Missing renegotiation_info and SCSV detected in " +

                    "ClientHello");

            }

            // Parse the extension.

            RenegotiationInfoSpec spec;

            try {

                spec = new RenegotiationInfoSpec(buffer);

            } catch (IOException ioe) {

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

                return;     // fatal() always throws, make the compiler happy.

            }

            if (!chc.conContext.isNegotiated) {     // initial handshake

                // If the extension is present, set the secure_renegotiation

                // flag to TRUE.  The client MUST then verify that the

                // length of the "renegotiated_connection" field is zero,

                // and if it is not, MUST abort the handshake (by sending

                // a fatal handshake_failure alert). [RFC 5746]

                if (spec.renegotiatedConnection.length != 0) {

                    chc.conContext.fatal(Alert.HANDSHAKE_FAILURE,

                        "Invalid renegotiation_info in ServerHello: " +

                        "not empty renegotiated_connection");

                }

                chc.conContext.secureRenegotiation = true;

            } else {        // renegotiation

                // The client MUST then verify that the first half of the

                // "renegotiated_connection" field is equal to the saved

                // client_verify_data value, and the second half is equal to the

                // saved server_verify_data value.  If they are not, the client

                // MUST abort the handshake. [RFC 5746]

                int infoLen = chc.conContext.clientVerifyData.length +

                              chc.conContext.serverVerifyData.length;

                if (spec.renegotiatedConnection.length != infoLen) {

                    chc.conContext.fatal(Alert.HANDSHAKE_FAILURE,

                        "Invalid renegotiation_info in ServerHello: " +

                        "invalid renegotiated_connection length (" +

                        spec.renegotiatedConnection.length + ")");

                }

                byte[] cvd = chc.conContext.clientVerifyData;

                if (!Arrays.equals(spec.renegotiatedConnection,

                        0, cvd.length, cvd, 0, cvd.length)) {

                    chc.conContext.fatal(Alert.HANDSHAKE_FAILURE,

                        "Invalid renegotiation_info in ServerHello: " +

                        "unmatched client_verify_data value");

                }

                byte[] svd = chc.conContext.serverVerifyData;

                if (!Arrays.equals(spec.renegotiatedConnection,

                        cvd.length, infoLen, svd, 0, svd.length)) {

                    chc.conContext.fatal(Alert.HANDSHAKE_FAILURE,

                        "Invalid renegotiation_info in ServerHello: " +

                        "unmatched server_verify_data value");

                }

            }

            // Update the context.

            chc.handshakeExtensions.put(

                    SH_RENEGOTIATION_INFO, RenegotiationInfoSpec.NOMINAL);

            // No impact on session resumption.