org.filesys.server.auth.ntlm.NTLMv2Blob Maven / Gradle / Ivy
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/*
* Copyright (C) 2006-2010 Alfresco Software Limited.
* Copyright (C) 2018 GK Spencer
*
* This file is part of Alfresco
*
* Alfresco is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Alfresco 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with Alfresco. If not, see Contains methods to pack/unpack and calculate the hash of an NTLMv2 blob.
*
* @author gkspencer
*/
public class NTLMv2Blob {
// Constants
public static final int HMAC_LEN = 16;
public static final int CHALLENGE_LEN = 8;
// Offsets
public static final int OFFSET_HMAC = 0;
public static final int OFFSET_HEADER = 16;
public static final int OFFSET_RESERVED = 20;
public static final int OFFSET_TIMESTAMP = 24;
public static final int OFFSET_CHALLENGE = 32;
public static final int OFFSET_UNKNOWN = 36;
public static final int OFFSET_TARGETINFO = 44;
// NTLMv2 blob
private byte[] m_blob;
private int m_offset;
private int m_len;
/**
* Class constructor
*
* @param buf byte[]
*/
public NTLMv2Blob(byte[] buf) {
m_blob = buf;
m_offset = 0;
m_len = m_blob.length;
}
/**
* Class constructor
*
* @param buf byte[]
* @param offset int
* @param len int
*/
public NTLMv2Blob(byte[] buf, int offset, int len) {
m_blob = buf;
m_offset = offset;
m_len = len;
}
/**
* Return the buffer
*
* @return byte[]
*/
public final byte[] getBuffer() {
return m_blob;
}
/**
* Return the offset
*
* @return int
*/
public final int getOffset() {
return m_offset;
}
/**
* Return the blob length
*
* @return int
*/
public final int getLength() {
return m_len;
}
/**
* Return the HMAC from the buffer
*
* @return byte[]
*/
public final byte[] getHMAC() {
byte[] hmac = new byte[HMAC_LEN];
System.arraycopy(m_blob, m_offset, hmac, 0, HMAC_LEN);
return hmac;
}
/**
* Return the timestamp from the buffer, in NT 64bit time format
*
* @return long
*/
public final long getTimeStamp() {
return DataPacker.getIntelLong(m_blob, m_offset + OFFSET_TIMESTAMP);
}
/**
* Return the client challenge
*
* @return byte[]
*/
public final byte[] getClientChallenge() {
byte[] challenge = new byte[CHALLENGE_LEN];
System.arraycopy(m_blob, m_offset + OFFSET_CHALLENGE, challenge, 0, CHALLENGE_LEN);
return challenge;
}
/**
* Get the target information list
*
* @return List of target information
*/
public final List getTargetInfo() {
// Wrap a data buffer around the target information section of the buffer
DataBuffer tBuf = new DataBuffer( getBuffer(), getOffset() + OFFSET_TARGETINFO, getLength() - OFFSET_TARGETINFO);
List tList = null;
boolean endOfList = false;
while ( endOfList == false) {
// Get the current target information type and data length
TargetInfo.Type tTyp = TargetInfo.Type.fromInt( tBuf.getShort());
int tLen = tBuf.getShort();
if ( tTyp == TargetInfo.Type.END_OF_LIST) {
endOfList = true;
continue;
}
// Get the target information value
TargetInfo tInfo = null;
switch ( tTyp) {
// String type target information
case SERVER:
case DOMAIN:
case FULL_DNS:
case DNS_DOMAIN:
case DNS_TREE:
case SPN:
String sVal = tBuf.getString( tLen/2, true);
tInfo = new StringTargetInfo( tTyp, sVal);
break;
// Timestamp type target information
case TIMESTAMP:
long lVal = tBuf.getLong();
tInfo = new TimestampTargetInfo( lVal);
break;
// Integer type target information
case FLAGS:
int iVal = tBuf.getInt();
tInfo = new FlagsTargetInfo( iVal);
break;
}
// Add the target information to the list if valid
if ( tInfo != null) {
if ( tList == null)
tList = new ArrayList<>();
tList.add( tInfo);
}
}
// Return the target information list
return tList;
}
/**
* Calculate the HMAC of the blob using the specified NTLMv2 hash and challenge
*
* @param challenge byte[]
* @param v2hash byte[]
* @return byte[]
* @exception Exception Invalid hash
*/
public final byte[] calculateHMAC(byte[] challenge, byte[] v2hash)
throws Exception {
// Create a copy of the NTLMv2 blob with room for the challenge
byte[] blob = new byte[(m_len - HMAC_LEN) + CHALLENGE_LEN];
System.arraycopy(challenge, 0, blob, 0, CHALLENGE_LEN);
System.arraycopy(m_blob, m_offset + OFFSET_HEADER, blob, CHALLENGE_LEN, m_len - HMAC_LEN);
// Generate the HMAC of the blob using the v2 hash as the key
Mac hmacMd5 = Mac.getInstance("HMACMD5");
SecretKeySpec blobKey = new SecretKeySpec(v2hash, 0, v2hash.length, "MD5");
hmacMd5.init(blobKey);
return hmacMd5.doFinal(blob);
}
/**
* Calcualte the LMv2 HMAC value
*
* @param v2hash byte[]
* @param srvChallenge byte[]
* @param clChallenge byte[]
* @return byte[]
* @exception Exception Invalid hash
*/
public final byte[] calculateLMv2HMAC(byte[] v2hash, byte[] srvChallenge, byte[] clChallenge)
throws Exception {
// Concatenate the server and client challenges
byte[] blob = new byte[16];
System.arraycopy(srvChallenge, 0, blob, 0, srvChallenge.length);
System.arraycopy(clChallenge, 0, blob, 8, clChallenge.length);
// Generate the LMv2 HMAC of the blob using the v2 hash as the key
Mac hmacMd5 = Mac.getInstance("HMACMD5");
SecretKeySpec blobKey = new SecretKeySpec(v2hash, 0, v2hash.length, "MD5");
hmacMd5.init(blobKey);
return hmacMd5.doFinal(blob);
}
/**
* Dump the NTLMv2 blob details
*/
public final void Dump() {
System.out.println("NTLMv2 blob :");
System.out.println(" HMAC : " + HexDump.hexString(getHMAC()));
System.out.println(" Header : 0x" + Integer.toHexString(DataPacker.getIntelInt(m_blob, m_offset + OFFSET_HEADER)));
System.out.println(" Timestamp : " + new Date(NTTime.toJavaDate(getTimeStamp())));
System.out.println(" Challenge : " + HexDump.hexString(getClientChallenge()));
}
}