/*

 * Copyright (c) 2015, 2019, 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.security.PrivateKey;

import java.security.cert.X509Certificate;

import java.text.MessageFormat;

import java.util.ArrayList;

import java.util.Collection;

import java.util.Collections;

import java.util.HashSet;

import java.util.LinkedList;

import java.util.List;

import java.util.Locale;

import javax.net.ssl.SSLEngine;

import javax.net.ssl.SSLSocket;

import javax.net.ssl.X509ExtendedKeyManager;

import javax.security.auth.x500.X500Principal;

import sun.security.ssl.CipherSuite.KeyExchange;

import sun.security.ssl.SSLHandshake.HandshakeMessage;

import sun.security.ssl.X509Authentication.X509Possession;

/**

 * Pack of the CertificateRequest handshake message.

 */

final class CertificateRequest {

    static final SSLConsumer t10HandshakeConsumer =

        new T10CertificateRequestConsumer();

    static final HandshakeProducer t10HandshakeProducer =

        new T10CertificateRequestProducer();

    static final SSLConsumer t12HandshakeConsumer =

        new T12CertificateRequestConsumer();

    static final HandshakeProducer t12HandshakeProducer =

        new T12CertificateRequestProducer();

    static final SSLConsumer t13HandshakeConsumer =

        new T13CertificateRequestConsumer();

    static final HandshakeProducer t13HandshakeProducer =

        new T13CertificateRequestProducer();

    // TLS 1.2 and prior versions

    private static enum ClientCertificateType {

        // RFC 2246

        RSA_SIGN            ((byte)0x01, "rsa_sign", "RSA", true),

        DSS_SIGN            ((byte)0x02, "dss_sign", "DSA", true),

        RSA_FIXED_DH        ((byte)0x03, "rsa_fixed_dh"),

        DSS_FIXED_DH        ((byte)0x04, "dss_fixed_dh"),

        // RFC 4346

        RSA_EPHEMERAL_DH    ((byte)0x05, "rsa_ephemeral_dh"),

        DSS_EPHEMERAL_DH    ((byte)0x06, "dss_ephemeral_dh"),

        FORTEZZA_DMS        ((byte)0x14, "fortezza_dms"),

        // RFC 4492

        ECDSA_SIGN          ((byte)0x40, "ecdsa_sign",

                                             "EC", JsseJce.isEcAvailable()),

        RSA_FIXED_ECDH      ((byte)0x41, "rsa_fixed_ecdh"),

        ECDSA_FIXED_ECDH    ((byte)0x42, "ecdsa_fixed_ecdh");

        private static final byte[] CERT_TYPES =

                JsseJce.isEcAvailable() ? new byte[] {

                        ECDSA_SIGN.id,

                        RSA_SIGN.id,

                        DSS_SIGN.id

                    } :  new byte[] {

                        RSA_SIGN.id,

                        DSS_SIGN.id

                    };

        final byte id;

        final String name;

        final String keyAlgorithm;

        final boolean isAvailable;

        private ClientCertificateType(byte id, String name) {

            this(id, name, null, false);

        }

        private ClientCertificateType(byte id, String name,

                String keyAlgorithm, boolean isAvailable) {

            this.id = id;

            this.name = name;

            this.keyAlgorithm = keyAlgorithm;

            this.isAvailable = isAvailable;

        }

        private static String nameOf(byte id) {

            for (ClientCertificateType cct : ClientCertificateType.values()) {

                if (cct.id == id) {

                    return cct.name;

                }

            }

            return "UNDEFINED-CLIENT-CERTIFICATE-TYPE(" + (int)id + ")";

        }

        private static ClientCertificateType valueOf(byte id) {

            for (ClientCertificateType cct : ClientCertificateType.values()) {

                if (cct.id == id) {

                    return cct;

                }

            }

            return null;

        }

        private static String[] getKeyTypes(byte[] ids) {

            ArrayList<String> keyTypes = new ArrayList<>(3);

            for (byte id : ids) {

                ClientCertificateType cct = ClientCertificateType.valueOf(id);

                if (cct.isAvailable) {

                    keyTypes.add(cct.keyAlgorithm);

                }

            }

            return keyTypes.toArray(new String[0]);

        }

    }

    /**

     * The "CertificateRequest" handshake message for SSL 3.0 and TLS 1.0/1.1.

     */

    static final class T10CertificateRequestMessage extends HandshakeMessage {

        final byte[] types;                 // certificate types

        final List<byte[]> authorities;     // certificate authorities

        T10CertificateRequestMessage(HandshakeContext handshakeContext,

                X509Certificate[] trustedCerts, KeyExchange keyExchange) {

            super(handshakeContext);

            this.authorities = new ArrayList<>(trustedCerts.length);

            for (X509Certificate cert : trustedCerts) {

                X500Principal x500Principal = cert.getSubjectX500Principal();

                authorities.add(x500Principal.getEncoded());

            }

            this.types = ClientCertificateType.CERT_TYPES;

        }

        T10CertificateRequestMessage(HandshakeContext handshakeContext,

                ByteBuffer m) throws IOException {

            super(handshakeContext);

            // struct {

            //     ClientCertificateType certificate_types<1..2^8-1>;

            //     DistinguishedName certificate_authorities<0..2^16-1>;

            // } CertificateRequest;

            if (m.remaining() < 4) {

                throw handshakeContext.conContext.fatal(Alert.ILLEGAL_PARAMETER,

                    "Incorrect CertificateRequest message: no sufficient data");

            }

            this.types = Record.getBytes8(m);

            int listLen = Record.getInt16(m);

            if (listLen > m.remaining()) {

                throw handshakeContext.conContext.fatal(Alert.ILLEGAL_PARAMETER,

                    "Incorrect CertificateRequest message:no sufficient data");

            }

            if (listLen > 0) {

                this.authorities = new LinkedList<>();

                while (listLen > 0) {

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

                    byte[] encoded = Record.getBytes16(m);

                    listLen -= (2 + encoded.length);

                    authorities.add(encoded);

                }

            } else {

                this.authorities = Collections.emptyList();

            }

        }

        String[] getKeyTypes() {

            return  ClientCertificateType.getKeyTypes(types);

        }

        X500Principal[] getAuthorities() {

            List<X500Principal> principals =

                    new ArrayList<>(authorities.size());

            for (byte[] encoded : authorities) {

                X500Principal principal = new X500Principal(encoded);

                principals.add(principal);

            }

            return principals.toArray(new X500Principal[0]);

        }

        @Override

        public SSLHandshake handshakeType() {

            return SSLHandshake.CERTIFICATE_REQUEST;

        }

        @Override

        public int messageLength() {

            int len = 1 + types.length + 2;

            for (byte[] encoded : authorities) {

                len += encoded.length + 2;

            }

            return len;

        }

        @Override

        public void send(HandshakeOutStream hos) throws IOException {

            hos.putBytes8(types);

            int listLen = 0;

            for (byte[] encoded : authorities) {

                listLen += encoded.length + 2;

            }

            hos.putInt16(listLen);

            for (byte[] encoded : authorities) {

                hos.putBytes16(encoded);

            }

        }

        @Override

        public String toString() {

            MessageFormat messageFormat = new MessageFormat(

                    "\"CertificateRequest\": '{'\n" +

                    "  \"certificate types\": {0}\n" +

                    "  \"certificate authorities\": {1}\n" +

                    "'}'",

                    Locale.ENGLISH);

            List<String> typeNames = new ArrayList<>(types.length);

            for (byte type : types) {

                typeNames.add(ClientCertificateType.nameOf(type));

            }

            List<String> authorityNames = new ArrayList<>(authorities.size());

            for (byte[] encoded : authorities) {

                X500Principal principal = new X500Principal(encoded);

                authorityNames.add(principal.toString());

            }

            Object[] messageFields = {

                typeNames,

                authorityNames

            };

            return messageFormat.format(messageFields);

        }

    }

    /**

     * The "CertificateRequest" handshake message producer for SSL 3.0 and

     * TLS 1.0/1.1.

     */

    private static final

            class T10CertificateRequestProducer implements HandshakeProducer {

        // Prevent instantiation of this class.

        private T10CertificateRequestProducer() {

            // blank

        }

        @Override

        public byte[] produce(ConnectionContext context,

                HandshakeMessage message) throws IOException {

            // The producing happens in server side only.

            ServerHandshakeContext shc = (ServerHandshakeContext)context;

            X509Certificate[] caCerts =

                    shc.sslContext.getX509TrustManager().getAcceptedIssuers();

            T10CertificateRequestMessage crm = new T10CertificateRequestMessage(

                    shc, caCerts, shc.negotiatedCipherSuite.keyExchange);

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

                SSLLogger.fine(

                    "Produced CertificateRequest handshake message", crm);

            }

            // Output the handshake message.

            crm.write(shc.handshakeOutput);

            shc.handshakeOutput.flush();

            //

            // update

            //

            shc.handshakeConsumers.put(SSLHandshake.CERTIFICATE.id,

                    SSLHandshake.CERTIFICATE);

            shc.handshakeConsumers.put(SSLHandshake.CERTIFICATE_VERIFY.id,

                    SSLHandshake.CERTIFICATE_VERIFY);

            // The handshake message has been delivered.

            return null;

        }

    }

    /**

     * The "CertificateRequest" handshake message consumer for SSL 3.0 and

     * TLS 1.0/1.1.

     */

    private static final

            class T10CertificateRequestConsumer implements SSLConsumer {

        // Prevent instantiation of this class.

        private T10CertificateRequestConsumer() {

            // 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.CERTIFICATE_REQUEST.id);

            SSLConsumer certStatCons = chc.handshakeConsumers.remove(

                    SSLHandshake.CERTIFICATE_STATUS.id);

            if (certStatCons != null) {

                // Stapling was active but no certificate status message

                // was sent.  We need to run the absence handler which will

                // check the certificate chain.

                CertificateStatus.handshakeAbsence.absent(context, null);

            }

            T10CertificateRequestMessage crm =

                    new T10CertificateRequestMessage(chc, message);

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

                SSLLogger.fine(

                        "Consuming CertificateRequest handshake message", crm);

            }

            //

            // validate

            //

            // blank

            //

            // update

            //

            // An empty client Certificate handshake message may be allow.

            chc.handshakeProducers.put(SSLHandshake.CERTIFICATE.id,

                    SSLHandshake.CERTIFICATE);

            X509ExtendedKeyManager km = chc.sslContext.getX509KeyManager();

            String clientAlias = null;

            if (chc.conContext.transport instanceof SSLSocketImpl) {

                clientAlias = km.chooseClientAlias(crm.getKeyTypes(),

                    crm.getAuthorities(), (SSLSocket)chc.conContext.transport);

            } else if (chc.conContext.transport instanceof SSLEngineImpl) {

                clientAlias = km.chooseEngineClientAlias(crm.getKeyTypes(),

                    crm.getAuthorities(), (SSLEngine)chc.conContext.transport);

            }

            if (clientAlias == null) {

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

                    SSLLogger.warning("No available client authentication");

                }

                return;

            }

            PrivateKey clientPrivateKey = km.getPrivateKey(clientAlias);

            if (clientPrivateKey == null) {

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

                    SSLLogger.warning("No available client private key");

                }

                return;

            }

            X509Certificate[] clientCerts = km.getCertificateChain(clientAlias);

            if ((clientCerts == null) || (clientCerts.length == 0)) {

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

                    SSLLogger.warning("No available client certificate");

                }

                return;

            }

            chc.handshakePossessions.add(

                    new X509Possession(clientPrivateKey, clientCerts));

            chc.handshakeProducers.put(SSLHandshake.CERTIFICATE_VERIFY.id,

                    SSLHandshake.CERTIFICATE_VERIFY);

        }

    }

    /**

     * The CertificateRequest handshake message for TLS 1.2.

     */

    static final class T12CertificateRequestMessage extends HandshakeMessage {

        final byte[] types;                 // certificate types

        final int[] algorithmIds;           // supported signature algorithms

        final List<byte[]> authorities;     // certificate authorities

        T12CertificateRequestMessage(HandshakeContext handshakeContext,

                X509Certificate[] trustedCerts, KeyExchange keyExchange,

                List<SignatureScheme> signatureSchemes) throws IOException {

            super(handshakeContext);

            this.types = ClientCertificateType.CERT_TYPES;

            if (signatureSchemes == null || signatureSchemes.isEmpty()) {

                throw handshakeContext.conContext.fatal(Alert.ILLEGAL_PARAMETER,

                        "No signature algorithms specified for " +

                        "CertificateRequest hanshake message");

            }

            this.algorithmIds = new int[signatureSchemes.size()];

            int i = 0;

            for (SignatureScheme scheme : signatureSchemes) {

                algorithmIds[i++] = scheme.id;

            }

            this.authorities = new ArrayList<>(trustedCerts.length);

            for (X509Certificate cert : trustedCerts) {

                X500Principal x500Principal = cert.getSubjectX500Principal();

                authorities.add(x500Principal.getEncoded());

            }

        }

        T12CertificateRequestMessage(HandshakeContext handshakeContext,

                ByteBuffer m) throws IOException {

            super(handshakeContext);

            // struct {

            //     ClientCertificateType certificate_types<1..2^8-1>;

            //     SignatureAndHashAlgorithm

            //       supported_signature_algorithms<2..2^16-2>;

            //     DistinguishedName certificate_authorities<0..2^16-1>;

            // } CertificateRequest;

            // certificate_authorities

            if (m.remaining() < 8) {

                throw handshakeContext.conContext.fatal(Alert.ILLEGAL_PARAMETER,

                        "Invalid CertificateRequest handshake message: " +

                        "no sufficient data");

            }

            this.types = Record.getBytes8(m);

            // supported_signature_algorithms

            if (m.remaining() < 6) {

                throw handshakeContext.conContext.fatal(Alert.ILLEGAL_PARAMETER,

                        "Invalid CertificateRequest handshake message: " +

                        "no sufficient data");

            }

            byte[] algs = Record.getBytes16(m);

            if (algs == null || algs.length == 0 || (algs.length & 0x01) != 0) {

                throw handshakeContext.conContext.fatal(Alert.ILLEGAL_PARAMETER,

                        "Invalid CertificateRequest handshake message: " +

                        "incomplete signature algorithms");

            }

            this.algorithmIds = new int[(algs.length >> 1)];

            for (int i = 0, j = 0; i < algs.length;) {

                byte hash = algs[i++];

                byte sign = algs[i++];

                algorithmIds[j++] = ((hash & 0xFF) << 8) | (sign & 0xFF);

            }

            // certificate_authorities

            if (m.remaining() < 2) {

                throw handshakeContext.conContext.fatal(Alert.ILLEGAL_PARAMETER,

                        "Invalid CertificateRequest handshake message: " +

                        "no sufficient data");

            }

            int listLen = Record.getInt16(m);

            if (listLen > m.remaining()) {

                throw handshakeContext.conContext.fatal(Alert.ILLEGAL_PARAMETER,

                    "Invalid CertificateRequest message: no sufficient data");

            }

            if (listLen > 0) {

                this.authorities = new LinkedList<>();

                while (listLen > 0) {

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

                    byte[] encoded = Record.getBytes16(m);

                    listLen -= (2 + encoded.length);

                    authorities.add(encoded);

                }

            } else {

                this.authorities = Collections.emptyList();

            }

        }

        String[] getKeyTypes() {

            return ClientCertificateType.getKeyTypes(types);

        }

        X500Principal[] getAuthorities() {

            List<X500Principal> principals =

                    new ArrayList<>(authorities.size());

            for (byte[] encoded : authorities) {

                X500Principal principal = new X500Principal(encoded);

                principals.add(principal);

            }

            return principals.toArray(new X500Principal[0]);

        }

        @Override

        public SSLHandshake handshakeType() {

            return SSLHandshake.CERTIFICATE_REQUEST;

        }

        @Override

        public int messageLength() {

            int len = 1 + types.length + 2 + (algorithmIds.length << 1) + 2;

            for (byte[] encoded : authorities) {