/*

 * Copyright (c) 2000, 2008, 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

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 */

/*

 *

 *  (C) Copyright IBM Corp. 1999 All Rights Reserved.

 *  Copyright 1997 The Open Group Research Institute.  All rights reserved.

 */

package sun.security.krb5;

import sun.security.util.*;

import sun.security.krb5.EncryptionKey;

import sun.security.krb5.internal.*;

import sun.security.krb5.internal.crypto.*;

import java.io.IOException;

import java.net.UnknownHostException;

import java.util.StringTokenizer;

import java.io.InterruptedIOException;

/**

 * This class encapsulates a Kerberos TGS-REQ that is sent from the

 * client to the KDC.

 */

public class KrbTgsReq extends KrbKdcReq {

    private PrincipalName princName;

    private PrincipalName servName;

    private TGSReq tgsReqMessg;

    private KerberosTime ctime;

    private Ticket secondTicket = null;

    private boolean useSubkey = false;

    EncryptionKey tgsReqKey;

    private static final boolean DEBUG = Krb5.DEBUG;

    private int defaultTimeout = 30*1000; // 30 seconds

     // Used in CredentialsUtil

    public KrbTgsReq(Credentials asCreds,

                     PrincipalName sname)

        throws KrbException, IOException {

        this(new KDCOptions(),

            asCreds,

            sname,

            null, // KerberosTime from

            null, // KerberosTime till

            null, // KerberosTime rtime

            null, // eTypes, // null, // int[] eTypes

            null, // HostAddresses addresses

            null, // AuthorizationData authorizationData

            null, // Ticket[] additionalTickets

            null); // EncryptionKey subSessionKey

    }

    // Called by Credentials, KrbCred

    KrbTgsReq(

            KDCOptions options,

            Credentials asCreds,

            PrincipalName sname,

            KerberosTime from,

            KerberosTime till,

            KerberosTime rtime,

            int[] eTypes,

            HostAddresses addresses,

            AuthorizationData authorizationData,

            Ticket[] additionalTickets,

            EncryptionKey subKey) throws KrbException, IOException {

        princName = asCreds.client;

        servName = sname;

        ctime = new KerberosTime(KerberosTime.NOW);

        // check if they are valid arguments. The optional fields

        // should be  consistent with settings in KDCOptions.

        if (options.get(KDCOptions.FORWARDABLE) &&

                (!(asCreds.flags.get(Krb5.TKT_OPTS_FORWARDABLE)))) {

            throw new KrbException(Krb5.KRB_AP_ERR_REQ_OPTIONS);

        }

        if (options.get(KDCOptions.FORWARDED)) {

            if (!(asCreds.flags.get(KDCOptions.FORWARDABLE)))

                throw new KrbException(Krb5.KRB_AP_ERR_REQ_OPTIONS);

        }

        if (options.get(KDCOptions.PROXIABLE) &&

                (!(asCreds.flags.get(Krb5.TKT_OPTS_PROXIABLE)))) {

            throw new KrbException(Krb5.KRB_AP_ERR_REQ_OPTIONS);

        }

        if (options.get(KDCOptions.PROXY)) {

            if (!(asCreds.flags.get(KDCOptions.PROXIABLE)))

                throw new KrbException(Krb5.KRB_AP_ERR_REQ_OPTIONS);

        }

        if (options.get(KDCOptions.ALLOW_POSTDATE) &&

                (!(asCreds.flags.get(Krb5.TKT_OPTS_MAY_POSTDATE)))) {

            throw new KrbException(Krb5.KRB_AP_ERR_REQ_OPTIONS);

        }

        if (options.get(KDCOptions.RENEWABLE) &&

                (!(asCreds.flags.get(Krb5.TKT_OPTS_RENEWABLE)))) {

            throw new KrbException(Krb5.KRB_AP_ERR_REQ_OPTIONS);

        }

        if (options.get(KDCOptions.POSTDATED)) {

            if (!(asCreds.flags.get(KDCOptions.POSTDATED)))

                throw new KrbException(Krb5.KRB_AP_ERR_REQ_OPTIONS);

        } else {

            if (from != null)  from = null;

        }

        if (options.get(KDCOptions.RENEWABLE)) {

            if (!(asCreds.flags.get(KDCOptions.RENEWABLE)))

                throw new KrbException(Krb5.KRB_AP_ERR_REQ_OPTIONS);

        } else {

            if (rtime != null)  rtime = null;

        }

        if (options.get(KDCOptions.ENC_TKT_IN_SKEY)) {

            if (additionalTickets == null)

                throw new KrbException(Krb5.KRB_AP_ERR_REQ_OPTIONS);

            // in TGS_REQ there could be more than one additional

            // tickets,  but in file-based credential cache,

            // there is only one additional ticket field.

                secondTicket = additionalTickets[0];

        } else {

            if (additionalTickets != null)

                additionalTickets = null;

        }

        tgsReqMessg = createRequest(

                options,

                asCreds.ticket,

                asCreds.key,

                ctime,

                princName,

                princName.getRealm(),

                servName,

                from,

                till,

                rtime,

                eTypes,

                addresses,

                authorizationData,

                additionalTickets,

                subKey);

        obuf = tgsReqMessg.asn1Encode();

        // XXX We need to revisit this to see if can't move it

        // up such that FORWARDED flag set in the options

        // is included in the marshaled request.

        /*

         * If this is based on a forwarded ticket, record that in the

         * options, because the returned TgsRep will contain the

         * FORWARDED flag set.

         */

        if (asCreds.flags.get(KDCOptions.FORWARDED))

            options.set(KDCOptions.FORWARDED, true);

    }

    /**

     * Sends a TGS request to the realm of the target.

     * @throws KrbException

     * @throws IOException

     */

    public String send() throws IOException, KrbException {

        String realmStr = null;

        if (servName != null)

            realmStr = servName.getRealmString();

        return (send(realmStr));

    }

    public KrbTgsRep getReply()

        throws KrbException, IOException {

        return new KrbTgsRep(ibuf, this);

    }

    /**

     * Sends the request, waits for a reply, and returns the Credentials.

     * Used in Credentials, KrbCred, and internal/CredentialsUtil.

     */

    public Credentials sendAndGetCreds() throws IOException, KrbException {

        KrbTgsRep tgs_rep = null;

        String kdc = null;

        try {

            kdc = send();

            tgs_rep = getReply();

        } catch (KrbException ke) {

            if (ke.returnCode() == Krb5.KRB_ERR_RESPONSE_TOO_BIG) {

                // set useTCP and retry

                send(servName.getRealmString(), kdc, true);

                tgs_rep = getReply();

            } else {

                throw ke;

            }

        }

        return tgs_rep.getCreds();

    }

    KerberosTime getCtime() {

        return ctime;

    }

    private TGSReq createRequest(

                         KDCOptions kdc_options,

                         Ticket ticket,

                         EncryptionKey key,

                         KerberosTime ctime,

                         PrincipalName cname,

                         Realm crealm,

                         PrincipalName sname,

                         KerberosTime from,

                         KerberosTime till,

                         KerberosTime rtime,

                         int[] eTypes,

                         HostAddresses addresses,

                         AuthorizationData authorizationData,

                         Ticket[] additionalTickets,

                         EncryptionKey subKey)

        throws Asn1Exception, IOException, KdcErrException, KrbApErrException,

               UnknownHostException, KrbCryptoException {

        KerberosTime req_till = null;

        if (till == null) {

            req_till = new KerberosTime();

        } else {

            req_till = till;

        }

        /*

         * RFC 4120, Section 5.4.2.

         * For KRB_TGS_REP, the ciphertext is encrypted in the

         * sub-session key from the Authenticator, or if absent,

         * the session key from the ticket-granting ticket used

         * in the request.

         *

         * To support this, use tgsReqKey to remember which key to use.

         */

        tgsReqKey = key;

        int[] req_eTypes = null;

        if (eTypes == null) {

            req_eTypes = EType.getDefaults("default_tgs_enctypes");

            if (req_eTypes == null) {

                throw new KrbCryptoException(

            "No supported encryption types listed in default_tgs_enctypes");

            }

        } else {

            req_eTypes = eTypes;

        }

        EncryptionKey reqKey = null;

        EncryptedData encAuthorizationData = null;

        if (authorizationData != null) {

            byte[] ad = authorizationData.asn1Encode();

            if (subKey != null) {

                reqKey = subKey;

                tgsReqKey = subKey;    // Key to use to decrypt reply

                useSubkey = true;

                encAuthorizationData = new EncryptedData(reqKey, ad,

                    KeyUsage.KU_TGS_REQ_AUTH_DATA_SUBKEY);

            } else

                encAuthorizationData = new EncryptedData(key, ad,

                    KeyUsage.KU_TGS_REQ_AUTH_DATA_SESSKEY);

        }

        KDCReqBody reqBody = new KDCReqBody(

                                            kdc_options,

                                            cname,

                                            // crealm,

                                            sname.getRealm(), // TO

                                            sname,

                                            from,

                                            req_till,

                                            rtime,

                                            Nonce.value(),

                                            req_eTypes,

                                            addresses,

                                            encAuthorizationData,

                                            additionalTickets);

        byte[] temp = reqBody.asn1Encode(Krb5.KRB_TGS_REQ);

        // if the checksum type is one of the keyed checksum types,

        // use session key.

        Checksum cksum;

        switch (Checksum.CKSUMTYPE_DEFAULT) {

        case Checksum.CKSUMTYPE_RSA_MD4_DES:

        case Checksum.CKSUMTYPE_DES_MAC:

        case Checksum.CKSUMTYPE_DES_MAC_K:

        case Checksum.CKSUMTYPE_RSA_MD4_DES_K:

        case Checksum.CKSUMTYPE_RSA_MD5_DES:

        case Checksum.CKSUMTYPE_HMAC_SHA1_DES3_KD:

        case Checksum.CKSUMTYPE_HMAC_MD5_ARCFOUR:

        case Checksum.CKSUMTYPE_HMAC_SHA1_96_AES128:

        case Checksum.CKSUMTYPE_HMAC_SHA1_96_AES256:

            cksum = new Checksum(Checksum.CKSUMTYPE_DEFAULT, temp, key,

                KeyUsage.KU_PA_TGS_REQ_CKSUM);

            break;

        case Checksum.CKSUMTYPE_CRC32:

        case Checksum.CKSUMTYPE_RSA_MD4:

        case Checksum.CKSUMTYPE_RSA_MD5:

        default:

            cksum = new Checksum(Checksum.CKSUMTYPE_DEFAULT, temp);

        }

        // Usage will be KeyUsage.KU_PA_TGS_REQ_AUTHENTICATOR

        byte[] tgs_ap_req = new KrbApReq(

                                         new APOptions(),

                                         ticket,

                                         key,

                                         crealm,

                                         cname,

                                         cksum,

                                         ctime,

                                         reqKey,

                                         null,

                                         null).getMessage();

        PAData[] tgsPAData = new PAData[1];

        tgsPAData[0] = new PAData(Krb5.PA_TGS_REQ, tgs_ap_req);

        return new TGSReq(tgsPAData, reqBody);

    }

    TGSReq getMessage() {

        return tgsReqMessg;

    }

    Ticket getSecondTicket() {

        return secondTicket;

    }

    private static void debug(String message) {

        //      System.err.println(">>> KrbTgsReq: " + message);

    }

    boolean usedSubkey() {

        return useSubkey;

    }

}