com.hierynomus.ntlm.messages.NtlmChallenge Maven / Gradle / Ivy

/*
 * Copyright (C)2016 - SMBJ Contributors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.hierynomus.ntlm.messages;

import com.hierynomus.protocol.commons.Charsets;
import com.hierynomus.protocol.commons.EnumWithValue;
import com.hierynomus.protocol.commons.buffer.Buffer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.EnumSet;

/**
 * [MS-NLMP].pdf 2.2.1.2 CHALLENGE_MESSAGE
 */
public class NtlmChallenge extends NtlmPacket {
    private static final Logger logger = LoggerFactory.getLogger(NtlmChallenge.class);

    private int targetNameLen;
    private int targetNameBufferOffset;
    private EnumSet negotiateFlags;
    private byte[] serverChallenge;
    private WindowsVersion version;
    private int targetInfoLen;
    private int targetInfoBufferOffset;
    private String targetName;
    private TargetInfo targetInfo;

    @Override
    public void read(Buffer.PlainBuffer buffer) throws Buffer.BufferException {
        buffer.readString(Charsets.UTF_8, 8); // Signature (8 bytes) (NTLMSSP\0)
        buffer.readUInt32(); // MessageType (4 bytes)
        readTargetNameFields(buffer); // TargetNameFields (8 bytes)
        negotiateFlags = EnumWithValue.EnumUtils.toEnumSet(buffer.readUInt32(), NtlmNegotiateFlag.class); // NegotiateFlags (4 bytes)
        serverChallenge = buffer.readRawBytes(8); // ServerChallenge (8 bytes)
        buffer.skip(8); // Reserved (8 bytes)
        readTargetInfoFields(buffer); // TargetInfoFields(8 bytes)
        readVersion(buffer);
        readTargetName(buffer);
        readTargetInfo(buffer);
    }

    private void readTargetInfo(Buffer.PlainBuffer buffer) throws Buffer.BufferException {
        if (targetInfoLen > 0) {
            // Move to where buffer begins
            buffer.rpos(targetInfoBufferOffset);
            this.targetInfo = new TargetInfo().readFrom(buffer);
        }
    }

    private void readTargetName(Buffer.PlainBuffer buffer) throws Buffer.BufferException {
        if (targetNameLen > 0) {
            // Move to where buffer begins
            buffer.rpos(targetNameBufferOffset);
            targetName = buffer.readString(Charsets.UTF_16LE, targetNameLen / 2);
        }
    }

    private void readVersion(Buffer.PlainBuffer buffer) throws Buffer.BufferException {
        if (negotiateFlags.contains(NtlmNegotiateFlag.NTLMSSP_NEGOTIATE_VERSION)) {
            this.version = new WindowsVersion().readFrom(buffer);
            logger.debug("Windows version = {}", this.version);
        } else {
            buffer.skip(8);
        }
    }

    private void readTargetNameFields(Buffer.PlainBuffer buffer) throws Buffer.BufferException {
        targetNameLen = buffer.readUInt16(); // TargetNameLen (2 bytes)
        buffer.skip(2); // TargetNameMaxLen (2 bytes)
        targetNameBufferOffset = buffer.readUInt32AsInt(); // TargetNameBufferOffset (4 bytes)
    }

    private void readTargetInfoFields(Buffer.PlainBuffer buffer) throws Buffer.BufferException {
        if (negotiateFlags.contains(NtlmNegotiateFlag.NTLMSSP_NEGOTIATE_TARGET_INFO)) {
            targetInfoLen = buffer.readUInt16(); // TargetInfoLen (2 bytes)
            buffer.skip(2); // TargetInfoMaxLen (2 bytes)
            targetInfoBufferOffset = buffer.readUInt32AsInt(); // TargetInfoBufferOffset (2 bytes)
        } else {
            buffer.skip(8);
        }
    }

    public String getTargetName() {
        return targetName;
    }

    public byte[] getServerChallenge() {
        return serverChallenge;
    }

    public EnumSet getNegotiateFlags() {
        return negotiateFlags;
    }

    public TargetInfo getTargetInfo() {
        return targetInfo;
    }

    public WindowsVersion getVersion() {
        return version;
    }
}