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 * 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.

 *

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package sun.security.jgss.spnego;

import java.io.*;

import java.util.*;

import org.ietf.jgss.*;

import sun.security.jgss.*;

import sun.security.util.*;

/**

 * Implements the SPNEGO NegTokenTarg token

 * as specified in RFC 2478

 *

 * NegTokenTarg ::= SEQUENCE {

 *      negResult   [0] ENUMERATED {

 *              accept_completed        (0),

 *              accept_incomplete       (1),

 *              reject                  (2) }   OPTIONAL,

 *      supportedMech   [1] MechType            OPTIONAL,

 *      responseToken   [2] OCTET STRING        OPTIONAL,

 *      mechListMIC     [3] OCTET STRING        OPTIONAL

 * }

 *

 * MechType::= OBJECT IDENTIFIER

 *

 *

 * @author Seema Malkani

 * @since 1.6

 */

public class NegTokenTarg extends SpNegoToken {

    private int negResult = 0;

    private Oid supportedMech = null;

    private byte[] responseToken = null;

    private byte[] mechListMIC = null;

    NegTokenTarg(int result, Oid mech, byte[] token, byte[] mechListMIC)

    {

        super(NEG_TOKEN_TARG_ID);

        this.negResult = result;

        this.supportedMech = mech;

        this.responseToken = token;

        this.mechListMIC = mechListMIC;

    }

    // Used by sun.security.jgss.wrapper.NativeGSSContext

    // to parse SPNEGO tokens

    public NegTokenTarg(byte[] in) throws GSSException {

        super(NEG_TOKEN_TARG_ID);

        parseToken(in);

    }

    final byte[] encode() throws GSSException {

        try {

            // create negTargToken

            DerOutputStream targToken = new DerOutputStream();

            // write the negotiated result with CONTEXT 00

            DerOutputStream result = new DerOutputStream();

            result.putEnumerated(negResult);

            targToken.write(DerValue.createTag(DerValue.TAG_CONTEXT,

                                true, (byte) 0x00), result);

            // supportedMech with CONTEXT 01

            if (supportedMech != null) {

                DerOutputStream mech = new DerOutputStream();

                byte[] mechType = supportedMech.getDER();

                mech.write(mechType);

                targToken.write(DerValue.createTag(DerValue.TAG_CONTEXT,

                                                true, (byte) 0x01), mech);

            }

            // response Token with CONTEXT 02

            if (responseToken != null) {

                DerOutputStream rspToken = new DerOutputStream();

                rspToken.putOctetString(responseToken);

                targToken.write(DerValue.createTag(DerValue.TAG_CONTEXT,

                                        true, (byte) 0x02), rspToken);

            }

            // mechListMIC with CONTEXT 03

            if (mechListMIC != null) {

                if (DEBUG) {

                    System.out.println("SpNegoToken NegTokenTarg: " +

                                                "sending MechListMIC");

                }

                DerOutputStream mic = new DerOutputStream();

                mic.putOctetString(mechListMIC);

                targToken.write(DerValue.createTag(DerValue.TAG_CONTEXT,

                                        true, (byte) 0x03), mic);

            } else if (GSSUtil.useMSInterop()) {

                // required for MS-interoperability

                if (responseToken != null) {

                    if (DEBUG) {

                        System.out.println("SpNegoToken NegTokenTarg: " +

                                "sending additional token for MS Interop");

                    }

                    DerOutputStream rspToken = new DerOutputStream();

                    rspToken.putOctetString(responseToken);

                    targToken.write(DerValue.createTag(DerValue.TAG_CONTEXT,

                                                true, (byte) 0x03), rspToken);

                }

            }

            // insert in a SEQUENCE

            DerOutputStream out = new DerOutputStream();

            out.write(DerValue.tag_Sequence, targToken);

            return out.toByteArray();

        } catch (IOException e) {

            throw new GSSException(GSSException.DEFECTIVE_TOKEN, -1,

                "Invalid SPNEGO NegTokenTarg token : " + e.getMessage());

        }

    }

    private void parseToken(byte[] in) throws GSSException {

        try {

            DerValue der = new DerValue(in);

            // verify NegotiationToken type token

            if (!der.isContextSpecific((byte) NEG_TOKEN_TARG_ID)) {

                throw new IOException("SPNEGO NegoTokenTarg : " +

                        "did not have the right token type");

            }

            DerValue tmp1 = der.data.getDerValue();

            if (tmp1.tag != DerValue.tag_Sequence) {

                throw new IOException("SPNEGO NegoTokenTarg : " +

                        "did not have the Sequence tag");

            }

            // parse various fields if present

            int lastField = -1;

            while (tmp1.data.available() > 0) {

                DerValue tmp2 = tmp1.data.getDerValue();

                if (tmp2.isContextSpecific((byte)0x00)) {

                    lastField = checkNextField(lastField, 0);

                    negResult = tmp2.data.getEnumerated();

                    if (DEBUG) {

                        System.out.println("SpNegoToken NegTokenTarg: negotiated" +

                                    " result = " + getNegoResultString(negResult));

                    }

                } else if (tmp2.isContextSpecific((byte)0x01)) {

                    lastField = checkNextField(lastField, 1);

                    ObjectIdentifier mech = tmp2.data.getOID();

                    supportedMech = new Oid(mech.toString());

                    if (DEBUG) {

                        System.out.println("SpNegoToken NegTokenTarg: " +

                                    "supported mechanism = " + supportedMech);

                    }

                } else if (tmp2.isContextSpecific((byte)0x02)) {

                    lastField = checkNextField(lastField, 2);

                    responseToken = tmp2.data.getOctetString();

                } else if (tmp2.isContextSpecific((byte)0x03)) {

                    lastField = checkNextField(lastField, 3);

                    if (!GSSUtil.useMSInterop()) {

                        mechListMIC = tmp2.data.getOctetString();

                        if (DEBUG) {

                            System.out.println("SpNegoToken NegTokenTarg: " +

                                                "MechListMIC Token = " +

                                                getHexBytes(mechListMIC));

                        }

                    }

                }

            }

        } catch (IOException e) {

            throw new GSSException(GSSException.DEFECTIVE_TOKEN, -1,

                "Invalid SPNEGO NegTokenTarg token : " + e.getMessage());

        }

    }

    int getNegotiatedResult() {

        return negResult;

    }

    // Used by sun.security.jgss.wrapper.NativeGSSContext

    // to find the supported mech in SPNEGO tokens

    public Oid getSupportedMech() {

        return supportedMech;

    }

    byte[] getResponseToken() {

        return responseToken;

    }

    byte[] getMechListMIC() {

        return mechListMIC;

    }

}