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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,

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 *

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package com.sun.security.ntlm;

import java.math.BigInteger;

import java.util.Arrays;

import java.util.Date;

import java.util.Locale;

/**

 * The NTLM client. Not multi-thread enabled.<p>

 * Example:

 * <pre>

 * Client client = new Client(null, "host", "dummy",

 *       "REALM", "t0pSeCr3t".toCharArray());

 * byte[] type1 = client.type1();

 * // Send type1 to server and receive response as type2

 * byte[] type3 = client.type3(type2, nonce);

 * // Send type3 to server

 * </pre>

 */

public final class Client extends NTLM {

    private String domain;

    private byte[] pw1, pw2;

    /**

     * Creates an NTLM Client instance.

     * @param version the NTLM version to use, which can be:

     * <ul>

     * <li>LM/NTLM: Original NTLM v1

     * <li>LM: Original NTLM v1, LM only

     * <li>NTLM: Original NTLM v1, NTLM only

     * <li>NTLM2: NTLM v1 with Client Challenge

     * <li>LMv2/NTLMv2: NTLM v2

     * <li>LMv2: NTLM v2, LM only

     * <li>NTLMv2: NTLM v2, NTLM only

     * </ul>

     * If null, "LMv2/NTLMv2" will be used.

     * @param hostname hostname of the client, can be null

     * @param username username to be authenticated, must not be null

     * @param domain domain of {@code username}, can be null

     * @param password password for {@code username}, must not be not null.

     * This method does not make any modification to this parameter, it neither

     * needs to access the content of this parameter after this method call,

     * so you are free to modify or nullify this parameter after this call.

     * @throws NTLMException if {@code username} or {@code password} is null,

     * or {@code version} is illegal.

     *

     */

    public Client(String version, String hostname, String username,

            String domain, char[] password) throws NTLMException {

        super(version);

        if ((username == null || password == null)) {

            throw new NTLMException(NTLMException.PROTOCOL,

                    "username/password cannot be null");

        }

        this.hostname = hostname;

        this.username = username;

        this.domain = domain == null ? "" : domain;

        this.pw1 = getP1(password);

        this.pw2 = getP2(password);

        debug("NTLM Client: (h,u,t,version(v)) = (%s,%s,%s,%s(%s))\n",

                    hostname, username, domain, version, v.toString());

    }

    /**

     * Generates the Type 1 message

     * @return the message generated

     */

    public byte[] type1() {

        Writer p = new Writer(1, 32);

        // Negotiate always sign, Negotiate NTLM,

        // Request Target, Negotiate OEM, Negotiate unicode

        int flags = 0x8207;

        if (v != Version.NTLM) {

            flags |= 0x80000;

        }

        p.writeInt(12, flags);

        debug("NTLM Client: Type 1 created\n");

        debug(p.getBytes());

        return p.getBytes();

    }

    /**

     * Generates the Type 3 message

     * @param type2 the responding Type 2 message from server, must not be null

     * @param nonce random 8-byte array to be used in message generation,

     * must not be null except for original NTLM v1

     * @return the message generated

     * @throws NTLMException if the incoming message is invalid, or

     * {@code nonce} is null for NTLM v1.

     */

    public byte[] type3(byte[] type2, byte[] nonce) throws NTLMException {

        if (type2 == null || (v != Version.NTLM && nonce == null)) {

            throw new NTLMException(NTLMException.PROTOCOL,

                    "type2 and nonce cannot be null");

        }

        debug("NTLM Client: Type 2 received\n");

        debug(type2);

        Reader r = new Reader(type2);

        byte[] challenge = r.readBytes(24, 8);

        int inputFlags = r.readInt(20);

        boolean unicode = (inputFlags & 1) == 1;

        // IE uses domainFromServer to generate an alist if server has not

        // provided one. Firefox/WebKit do not. Neither do we.

        //String domainFromServer = r.readSecurityBuffer(12, unicode);

        int flags = 0x88200 | (inputFlags & 3);

        Writer p = new Writer(3, 64);

        byte[] lm = null, ntlm = null;

        p.writeSecurityBuffer(28, domain, unicode);

        p.writeSecurityBuffer(36, username, unicode);

        p.writeSecurityBuffer(44, hostname, unicode);

        if (v == Version.NTLM) {

            byte[] lmhash = calcLMHash(pw1);

            byte[] nthash = calcNTHash(pw2);

            if (writeLM) lm = calcResponse (lmhash, challenge);

            if (writeNTLM) ntlm = calcResponse (nthash, challenge);

        } else if (v == Version.NTLM2) {

            byte[] nthash = calcNTHash(pw2);

            lm = ntlm2LM(nonce);

            ntlm = ntlm2NTLM(nthash, nonce, challenge);

        } else {

            byte[] nthash = calcNTHash(pw2);

            if (writeLM) lm = calcV2(nthash,

                    username.toUpperCase(Locale.US)+domain, nonce, challenge);

            if (writeNTLM) {

                // Some client create a alist even if server does not send

                // one: (i16)2 (i16)len target_in_unicode (i16)0 (i16) 0

                byte[] alist = ((inputFlags & 0x800000) != 0) ?

                    r.readSecurityBuffer(40) : new byte[0];

                byte[] blob = new byte[32+alist.length];

                System.arraycopy(new byte[]{1,1,0,0,0,0,0,0}, 0, blob, 0, 8);

                // TS

                byte[] time = BigInteger.valueOf(new Date().getTime())

                        .add(new BigInteger("11644473600000"))

                        .multiply(BigInteger.valueOf(10000))

                        .toByteArray();

                for (int i=0; i<time.length; i++) {

                    blob[8+time.length-i-1] = time[i];

                }

                System.arraycopy(nonce, 0, blob, 16, 8);

                System.arraycopy(new byte[]{0,0,0,0}, 0, blob, 24, 4);

                System.arraycopy(alist, 0, blob, 28, alist.length);

                System.arraycopy(new byte[]{0,0,0,0}, 0,

                        blob, 28+alist.length, 4);

                ntlm = calcV2(nthash, username.toUpperCase(Locale.US)+domain,

                        blob, challenge);

            }

        }

        p.writeSecurityBuffer(12, lm);

        p.writeSecurityBuffer(20, ntlm);

        p.writeSecurityBuffer(52, new byte[0]);

        p.writeInt(60, flags);

        debug("NTLM Client: Type 3 created\n");

        debug(p.getBytes());

        return p.getBytes();

    }

    /**

     * Returns the domain value provided by server after the authentication

     * is complete, or the domain value provided by the client before it.

     * @return the domain

     */

    public String getDomain() {

        return domain;

    }

    /**

     * Disposes any password-derived information.

     */

    public void dispose() {

        Arrays.fill(pw1, (byte)0);

        Arrays.fill(pw2, (byte)0);

    }

}