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 * Copyright (c) 2010, 2011, 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 com.sun.security.sasl.ntlm;

import com.sun.security.ntlm.NTLMException;

import com.sun.security.ntlm.Server;

import java.io.IOException;

import java.security.GeneralSecurityException;

import java.util.Map;

import java.util.Random;

import javax.security.auth.callback.Callback;

import javax.security.auth.callback.CallbackHandler;

import javax.security.auth.callback.NameCallback;

import javax.security.auth.callback.PasswordCallback;

import javax.security.auth.callback.UnsupportedCallbackException;

import javax.security.sasl.*;

/**

  * Required callbacks:

  * - RealmCallback

  *      used as key by handler to fetch password, optional

  * - NameCallback

  *      used as key by handler to fetch password

  * - PasswordCallback

  *      handler must enter password for username/realm supplied

  *

  * Environment properties that affect the implementation:

  *

  * javax.security.sasl.qop

  *    String, quality of protection; only "auth" is accepted, default "auth"

  *

  * com.sun.security.sasl.ntlm.version

  *    String, name a specific version to accept:

  *      LM/NTLM: Original NTLM v1

  *      LM: Original NTLM v1, LM only

  *      NTLM: Original NTLM v1, NTLM only

  *      NTLM2: NTLM v1 with Client Challenge

  *      LMv2/NTLMv2: NTLM v2

  *      LMv2: NTLM v2, LM only

  *      NTLMv2: NTLM v2, NTLM only

  *    If not specified, use system property "ntlm.version". If also

  *    not specfied, all versions are accepted.

  *

  * com.sun.security.sasl.ntlm.domain

  *    String, the domain of the server, default is server name (fqdn parameter)

  *

  * com.sun.security.sasl.ntlm.random

  *    java.util.Random, the nonce source. Default null, an internal

  *    java.util.Random object will be used

  *

  * Negotiated Properties:

  *

  * javax.security.sasl.qop

  *    Always "auth"

  *

  * com.sun.security.sasl.ntlm.hostname

  *    The hostname for the user, provided by the client

  *

  */

final class NTLMServer implements SaslServer {

    private final static String NTLM_VERSION =

            "com.sun.security.sasl.ntlm.version";

    private final static String NTLM_DOMAIN =

            "com.sun.security.sasl.ntlm.domain";

    private final static String NTLM_HOSTNAME =

            "com.sun.security.sasl.ntlm.hostname";

    private static final String NTLM_RANDOM =

            "com.sun.security.sasl.ntlm.random";

    private final Random random;

    private final Server server;

    private byte[] nonce;

    private int step = 0;

    private String authzId;

    private final String mech;

    private String hostname;

    /**

     * @param mech not null

     * @param protocol not null for Sasl, ignored in NTLM

     * @param serverName not null for Sasl, can be null in NTLM. If non-null,

     * might be used as domain if not provided in props

     * @param props can be null

     * @param cbh can be null for Sasl, already null-checked in factory

     * @throws SaslException

     */

    NTLMServer(String mech, String protocol, String serverName,

            Map<String, ?> props, final CallbackHandler cbh)

            throws SaslException {

        this.mech = mech;

        String version = null;

        String domain = null;

        Random rtmp = null;

        if (props != null) {

            domain = (String) props.get(NTLM_DOMAIN);

            version = (String)props.get(NTLM_VERSION);

            rtmp = (Random)props.get(NTLM_RANDOM);

        }

        random = rtmp != null ? rtmp : new Random();

        if (version == null) {

            version = System.getProperty("ntlm.version");

        }

        if (domain == null) {

            domain = serverName;

        }

        if (domain == null) {

            throw new SaslException("Domain must be provided as"

                    + " the serverName argument or in props");

        }

        try {

            server = new Server(version, domain) {

                public char[] getPassword(String ntdomain, String username) {

                    try {

                        RealmCallback rcb = new RealmCallback(

                                "Domain: ", ntdomain);

                        NameCallback ncb = new NameCallback(

                                "Name: ", username);

                        PasswordCallback pcb = new PasswordCallback(

                                "Password: ", false);

                        cbh.handle(new Callback[] { rcb, ncb, pcb });

                        char[] passwd = pcb.getPassword();

                        pcb.clearPassword();

                        return passwd;

                    } catch (IOException ioe) {

                        return null;

                    } catch (UnsupportedCallbackException uce) {

                        return null;

                    }

                }

            };

        } catch (NTLMException ne) {

            throw new SaslException(

                    "NTLM: server creation failure", ne);

        }

        nonce = new byte[8];

    }

    @Override

    public String getMechanismName() {

        return mech;

    }

    @Override

    public byte[] evaluateResponse(byte[] response) throws SaslException {

        try {

            step++;

            if (step == 1) {

                random.nextBytes(nonce);

                return server.type2(response, nonce);

            } else {

                String[] out = server.verify(response, nonce);

                authzId = out[0];

                hostname = out[1];

                return null;

            }

        } catch (NTLMException ex) {

            throw new SaslException("NTLM: generate response failure", ex);

        }

    }

    @Override

    public boolean isComplete() {

        return step >= 2;

    }

    @Override

    public String getAuthorizationID() {

        if (!isComplete()) {

            throw new IllegalStateException("authentication not complete");

        }

        return authzId;

    }

    @Override

    public byte[] unwrap(byte[] incoming, int offset, int len)

            throws SaslException {

        throw new IllegalStateException("Not supported yet.");

    }

    @Override

    public byte[] wrap(byte[] outgoing, int offset, int len)

            throws SaslException {

        throw new IllegalStateException("Not supported yet.");

    }

    @Override

    public Object getNegotiatedProperty(String propName) {

        if (!isComplete()) {

            throw new IllegalStateException("authentication not complete");

        }

        switch (propName) {

            case Sasl.QOP:

                return "auth";

            case NTLM_HOSTNAME:

                return hostname;

            default:

                return null;

        }

    }

    @Override

    public void dispose() throws SaslException {

        return;

    }

}