/*
* Adito
*
* Copyright (C) 2003-2006 3SP LTD. All Rights Reserved
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
* This program 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 for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
package com.maverick.http;
import java.io.IOException;
import com.maverick.crypto.encoders.Base64;
import com.maverick.crypto.engines.DESEngine;
/**
*
* @author Lee David Painter <a href="mailto:lee@localhost"><lee@localhost></a>
*/
class NTLM {
/** Character encoding */
public static final String DEFAULT_CHARSET = "ASCII"; //$NON-NLS-1$
/** The current response */
private byte[] currentResponse;
/** The current position */
private int currentPosition = 0;
/** The character set to use for encoding the credentials */
private String credentialCharset = DEFAULT_CHARSET;
/**
* Returns the response for the given message.
*
* @param message the message that was received from the server.
* @param username the username to authenticate with.
* @param password the password to authenticate with.
* @param host The host.
* @param domain the NT domain to authenticate in.
* @return The response.
* @throws ProxyException If the messages cannot be retrieved.
*/
public String getResponseFor(String message, String username, String password, String host, String domain) throws IOException {
final String response;
if (message == null || message.trim().equals("")) { //$NON-NLS-1$
response = getType1Message(host, domain);
} else {
response = getType3Message(username, password, host, domain, parseType2Message(message));
}
return response;
}
/**
* Return the cipher for the specified key.
*
* @param key The key.
* @return Cipher The cipher.
* @throws IOException If the cipher cannot be retrieved.
*/
private DESEngine getCipher(byte[] key) throws IOException {
DESEngine cipher = new DESEngine();
key = setupKey(key);
cipher.init(true, key);
return cipher;
}
/**
* Adds parity bits to the key.
*
* @param key56 The key
* @return The modified key.
*/
private byte[] setupKey(byte[] key56) {
byte[] key = new byte[8];
key[0] = (byte) ((key56[0] >> 1) & 0xff);
key[1] = (byte) ((((key56[0] & 0x01) << 6) | (((key56[1] & 0xff) >> 2) & 0xff)) & 0xff);
key[2] = (byte) ((((key56[1] & 0x03) << 5) | (((key56[2] & 0xff) >> 3) & 0xff)) & 0xff);
key[3] = (byte) ((((key56[2] & 0x07) << 4) | (((key56[3] & 0xff) >> 4) & 0xff)) & 0xff);
key[4] = (byte) ((((key56[3] & 0x0f) << 3) | (((key56[4] & 0xff) >> 5) & 0xff)) & 0xff);
key[5] = (byte) ((((key56[4] & 0x1f) << 2) | (((key56[5] & 0xff) >> 6) & 0xff)) & 0xff);
key[6] = (byte) ((((key56[5] & 0x3f) << 1) | (((key56[6] & 0xff) >> 7) & 0xff)) & 0xff);
key[7] = (byte) (key56[6] & 0x7f);
for (int i = 0; i < key.length; i++) {
key[i] = (byte) (key[i] << 1);
}
return key;
}
/**
* Encrypt the data.
*
* @param key The key.
* @param bytes The data
* @return byte[] The encrypted data
* @throws HttpException If {@link Cipher.doFinal(byte[])} fails
*/
private byte[] encrypt(byte[] key, byte[] bytes) throws IOException {
DESEngine cipher = getCipher(key);
byte[] enc = cipher.doFinal(bytes);
return enc;
}
/**
* Prepares the object to create a response of the given length.
*
* @param length the length of the response to prepare.
*/
private void prepareResponse(int length) {
currentResponse = new byte[length];
currentPosition = 0;
}
/**
* Adds the given byte to the response.
*
* @param b the byte to add.
*/
private void addByte(byte b) {
currentResponse[currentPosition] = b;
currentPosition++;
}
/**
* Adds the given bytes to the response.
*
* @param bytes the bytes to add.
*/
private void addBytes(byte[] bytes) {
for (int i = 0; i < bytes.length; i++) {
currentResponse[currentPosition] = bytes[i];
currentPosition++;
}
}
/**
* Returns the response that has been generated after shrinking the array if
* required and base64 encodes the response.
*
* @return The response as above.
*/
private String getResponse() {
byte[] resp;
if (currentResponse.length > currentPosition) {
byte[] tmp = new byte[currentPosition];
for (int i = 0; i < currentPosition; i++) {
tmp[i] = currentResponse[i];
}
resp = tmp;
} else {
resp = currentResponse;
}
return new String(Base64.encode(resp));
}
/**
* Creates the first message (type 1 message) in the NTLM authentication
* sequence. This message includes the user name, domain and host for the
* authentication session.
*
* @param host the computer name of the host requesting authentication.
* @param domain The domain to authenticate with.
* @return String the message to add to the HTTP request header.
*/
public String getType1Message(String host, String domain) {
host = host.toUpperCase();
domain = domain.toUpperCase();
byte[] hostBytes = host.getBytes();
byte[] domainBytes = domain.getBytes();
int finalLength = 32 + hostBytes.length + domainBytes.length;
prepareResponse(finalLength);
// The initial id string.
byte[] protocol = "NTLMSSP".getBytes(); //$NON-NLS-1$
addBytes(protocol);
addByte((byte) 0);
// Type
addByte((byte) 1);
addByte((byte) 0);
addByte((byte) 0);
addByte((byte) 0);
// Flags
addByte((byte) 6);
addByte((byte) 82);
addByte((byte) 0);
addByte((byte) 0);
// Domain length (first time).
int iDomLen = domainBytes.length;
byte[] domLen = convertShort(iDomLen);
addByte(domLen[0]);
addByte(domLen[1]);
// Domain length (second time).
addByte(domLen[0]);
addByte(domLen[1]);
// Domain offset.
byte[] domOff = convertShort(hostBytes.length + 32);
addByte(domOff[0]);
addByte(domOff[1]);
addByte((byte) 0);
addByte((byte) 0);
// Host length (first time).
byte[] hostLen = convertShort(hostBytes.length);
addByte(hostLen[0]);
addByte(hostLen[1]);
// Host length (second time).
addByte(hostLen[0]);
addByte(hostLen[1]);
// Host offset (always 32).
byte[] hostOff = convertShort(32);
addByte(hostOff[0]);
addByte(hostOff[1]);
addByte((byte) 0);
addByte((byte) 0);
// Host String.
addBytes(hostBytes);
// Domain String.
addBytes(domainBytes);
return getResponse();
}
/**
* Extracts the server nonce out of the given message type 2.
*
* @param message the String containing the base64 encoded message.
* @return an array of 8 bytes that the server sent to be used when hashing
* the password.
*/
public byte[] parseType2Message(String message) {
// Decode the message first.
byte[] msg = Base64.decode(message);
byte[] nonce = new byte[8];
// The nonce is the 8 bytes starting from the byte in position 24.
for (int i = 0; i < 8; i++) {
nonce[i] = msg[i + 24];
}
return nonce;
}
/**
* Creates the type 3 message using the given server nonce. The type 3
* message includes all the information for authentication, host, domain,
* username and the result of encrypting the nonce sent by the server using
* the user's password as the key.
*
* @param user The user name. This should not include the domain name.
* @param password The password.
* @param host The host that is originating the authentication request.
* @param domain The domain to authenticate within.
* @param nonce the 8 byte array the server sent.
* @return The type 3 message.
* @throws IOException If {@encrypt(byte[],byte[])} fails.
*/
public String getType3Message(String user, String password, String host, String domain, byte[] nonce) throws IOException {
int ntRespLen = 0;
int lmRespLen = 24;
domain = domain.toUpperCase();
host = host.toUpperCase();
user = user.toUpperCase();
byte[] domainBytes = domain.getBytes();
byte[] hostBytes = host.getBytes();
byte[] userBytes = user.getBytes();
int domainLen = domainBytes.length;
int hostLen = hostBytes.length;
int userLen = userBytes.length;
int finalLength = 64 + ntRespLen + lmRespLen + domainLen + userLen + hostLen;
prepareResponse(finalLength);
byte[] ntlmssp = "NTLMSSP".getBytes(); //$NON-NLS-1$
addBytes(ntlmssp);
addByte((byte) 0);
addByte((byte) 3);
addByte((byte) 0);
addByte((byte) 0);
addByte((byte) 0);
// LM Resp Length (twice)
addBytes(convertShort(24));
addBytes(convertShort(24));
// LM Resp Offset
addBytes(convertShort(finalLength - 24));
addByte((byte) 0);
addByte((byte) 0);
// NT Resp Length (twice)
addBytes(convertShort(0));
addBytes(convertShort(0));
// NT Resp Offset
addBytes(convertShort(finalLength));
addByte((byte) 0);
addByte((byte) 0);
// Domain length (twice)
addBytes(convertShort(domainLen));
addBytes(convertShort(domainLen));
// Domain offset.
addBytes(convertShort(64));
addByte((byte) 0);
addByte((byte) 0);
// User Length (twice)
addBytes(convertShort(userLen));
addBytes(convertShort(userLen));
// User offset
addBytes(convertShort(64 + domainLen));
addByte((byte) 0);
addByte((byte) 0);
// Host length (twice)
addBytes(convertShort(hostLen));
addBytes(convertShort(hostLen));
// Host offset
addBytes(convertShort(64 + domainLen + userLen));
for (int i = 0; i < 6; i++) {
addByte((byte) 0);
}
// Message length
addBytes(convertShort(finalLength));
addByte((byte) 0);
addByte((byte) 0);
// Flags
addByte((byte) 6);
addByte((byte) 82);
addByte((byte) 0);
addByte((byte) 0);
addBytes(domainBytes);
addBytes(userBytes);
addBytes(hostBytes);
addBytes(hashPassword(password, nonce));
return getResponse();
}
/**
* Creates the LANManager and NT response for the given password using the
* given nonce.
*
* @param password the password to create a hash for.
* @param nonce the nonce sent by the server.
* @return The response.
* @throws HttpException If {@link #encrypt(byte[],byte[])} fails.
*/
private byte[] hashPassword(String password, byte[] nonce) throws IOException {
byte[] passw = password.toUpperCase().getBytes();
byte[] lmPw1 = new byte[7];
byte[] lmPw2 = new byte[7];
int len = passw.length;
if (len > 7) {
len = 7;
}
int idx;
for (idx = 0; idx < len; idx++) {
lmPw1[idx] = passw[idx];
}
for (; idx < 7; idx++) {
lmPw1[idx] = (byte) 0;
}
len = passw.length;
if (len > 14) {
len = 14;
}
for (idx = 7; idx < len; idx++) {
lmPw2[idx - 7] = passw[idx];
}
for (; idx < 14; idx++) {
lmPw2[idx - 7] = (byte) 0;
}
// Create LanManager hashed Password
byte[] magic = { (byte) 0x4B, (byte) 0x47, (byte) 0x53, (byte) 0x21, (byte) 0x40, (byte) 0x23, (byte) 0x24, (byte) 0x25 };
byte[] lmHpw1;
lmHpw1 = encrypt(lmPw1, magic);
byte[] lmHpw2 = encrypt(lmPw2, magic);
byte[] lmHpw = new byte[21];
for (int i = 0; i < lmHpw1.length; i++) {
lmHpw[i] = lmHpw1[i];
}
for (int i = 0; i < lmHpw2.length; i++) {
lmHpw[i + 8] = lmHpw2[i];
}
for (int i = 0; i < 5; i++) {
lmHpw[i + 16] = (byte) 0;
}
// Create the responses.
byte[] lmResp = new byte[24];
calcResp(lmHpw, nonce, lmResp);
return lmResp;
}
/**
* Takes a 21 byte array and treats it as 3 56-bit DES keys. The 8 byte
* plaintext is encrypted with each key and the resulting 24 bytes are
* stored in the results array.
*
* @param keys The keys.
* @param plaintext The plain text to encrypt.
* @param results Where the results are stored.
* @throws IOException If {@link #encrypt(byte[],byte[])} fails.
*/
private void calcResp(byte[] keys, byte[] plaintext, byte[] results) throws IOException {
byte[] keys1 = new byte[7];
byte[] keys2 = new byte[7];
byte[] keys3 = new byte[7];
for (int i = 0; i < 7; i++) {
keys1[i] = keys[i];
}
for (int i = 0; i < 7; i++) {
keys2[i] = keys[i + 7];
}
for (int i = 0; i < 7; i++) {
keys3[i] = keys[i + 14];
}
byte[] results1 = encrypt(keys1, plaintext);
byte[] results2 = encrypt(keys2, plaintext);
byte[] results3 = encrypt(keys3, plaintext);
for (int i = 0; i < 8; i++) {
results[i] = results1[i];
}
for (int i = 0; i < 8; i++) {
results[i + 8] = results2[i];
}
for (int i = 0; i < 8; i++) {
results[i + 16] = results3[i];
}
}
/**
* Converts a given number to a two byte array in little endian order.
*
* @param num the number to convert.
* @return The byte representation of <i>num</i> in little endian order.
*/
private byte[] convertShort(int num) {
byte[] val = new byte[2];
String hex = Integer.toString(num, 16);
while (hex.length() < 4) {
hex = "0" + hex; //$NON-NLS-1$
}
String low = hex.substring(2, 4);
String high = hex.substring(0, 2);
val[0] = (byte) Integer.parseInt(low, 16);
val[1] = (byte) Integer.parseInt(high, 16);
return val;
}
/**
* @return Returns the credentialCharset.
*/
public String getCredentialCharset() {
return credentialCharset;
}
/**
* @param credentialCharset The credentialCharset to set.
*/
public void setCredentialCharset(String credentialCharset) {
this.credentialCharset = credentialCharset;
}
}