/*
* Copyright (c) 2015, 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.
*
* 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
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package test;
import java.io.*;
import java.nio.file.*;
import java.math.BigInteger;
import java.net.*;
import java.util.*;
import java.util.regex.*;
import javax.xml.bind.DatatypeConverter;
/*
* A dummy LDAP server.
*
* Loads a sequence of LDAP messages from a capture file into its cache.
* It listens for LDAP requests, finds a match in its cache and sends the
* corresponding LDAP responses.
*
* The capture file contains an LDAP protocol exchange in the hexadecimal
* dump format emitted by sun.misc.HexDumpEncoder:
*
* xxxx: 00 11 22 33 44 55 66 77 88 99 aa bb cc dd ee ff ................
*
* Typically, LDAP protocol exchange is generated by running the LDAP client
* application program against a real LDAP server and setting the JNDI/LDAP
* environment property: com.sun.jndi.ldap.trace.ber to activate LDAP message
* tracing.
*/
public class LDAPServer {
/*
* A cache of LDAP requests and responses.
* Messages with the same ID are stored in a list.
* The first element in the list is the LDAP request,
* the remaining elements are the LDAP responses.
*/
private final Map<Integer,List<byte[]>> cache = new HashMap<>();
public LDAPServer(ServerSocket serverSocket, String filename)
throws Exception {
System.out.println("LDAPServer: Loading LDAP cache from: " + filename);
loadCaptureFile(filename);
System.out.println("LDAPServer: listening on port " +
serverSocket.getLocalPort());
try (Socket clientSocket = serverSocket.accept();
OutputStream out = clientSocket.getOutputStream();
InputStream in = clientSocket.getInputStream();) {
byte[] inBuffer = new byte[8192];
int count;
while ((count = in.read(inBuffer)) > 0) {
byte[] request = Arrays.copyOf(inBuffer, count);
int[] ids = getIDs(request);
int messageID = ids[0];
String operation = getOperation(ids[1]);
System.out.println("\nLDAPServer: received LDAP " + operation +
" [message ID " + messageID + "]");
List<byte[]> encodings = cache.get(messageID);
if (encodings == null ||
(!Arrays.equals(request, encodings.get(0)))) {
throw new Exception(
"LDAPServer: ERROR: received an LDAP " + operation +
" (ID=" + messageID + ") not present in cache");
}
for (int i = 1; i < encodings.size(); i++) {
// skip the request (at index 0)
byte[] response = encodings.get(i);
out.write(response, 0, response.length);
ids = getIDs(response);
System.out.println("\nLDAPServer: Sent LDAP " +
getOperation(ids[1]) + " [message ID " + ids[0] + "]");
}
}
} catch (IOException e) {
System.out.println("LDAPServer: ERROR: " + e);
throw e;
}
System.out.println("\n[LDAP server exited normally]");
}
/*
* Load a capture file containing an LDAP protocol exchange in the
* hexadecimal dump format emitted by sun.misc.HexDumpEncoder:
*
* xxxx: 00 11 22 33 44 55 66 77 88 99 aa bb cc dd ee ff ................
*/
private void loadCaptureFile(String filename) throws IOException {
StringBuilder hexString = new StringBuilder();
String pattern = "(....): (..) (..) (..) (..) (..) (..) (..) (..) (..) (..) (..) (..) (..) (..) (..) (..).*";
try (Scanner fileScanner = new Scanner(Paths.get(filename))) {
while (fileScanner.hasNextLine()){
try (Scanner lineScanner =
new Scanner(fileScanner.nextLine())) {
if (lineScanner.findInLine(pattern) == null) {
continue;
}
MatchResult result = lineScanner.match();
for (int i = 1; i <= result.groupCount(); i++) {
String digits = result.group(i);
if (digits.length() == 4) {
if (digits.equals("0000")) { // start-of-message
if (hexString.length() > 0) {
addToCache(hexString.toString());
hexString = new StringBuilder();
}
}
continue;
} else if (digits.equals(" ")) { // short message
continue;
}
hexString.append(digits);
}
}
}
}
addToCache(hexString.toString());
}
/*
* Add an LDAP encoding to the cache (by messageID key).
*/
private void addToCache(String hexString) throws IOException {
byte[] encoding = DatatypeConverter.parseHexBinary(hexString);
int[] ids = getIDs(encoding);
int messageID = ids[0];
List<byte[]> encodings = cache.get(messageID);
if (encodings == null) {
encodings = new ArrayList<>();
}
System.out.println(" adding LDAP " + getOperation(ids[1]) +
" with message ID " + messageID + " to the cache");
encodings.add(encoding);
cache.put(messageID, encodings);
}
/*
* Extracts the message ID and operation ID from an LDAP protocol encoding
* and returns them in a 2-element array of integers.
*/
private static int[] getIDs(byte[] encoding) throws IOException {
if (encoding[0] != 0x30) {
throw new IOException("Error: bad LDAP encoding in capture file: " +
"expected ASN.1 SEQUENCE tag (0x30), encountered " +
encoding[0]);
}
int index = 2;
if ((encoding[1] & 0x80) == 0x80) {
index += (encoding[1] & 0x0F);
}
if (encoding[index] != 0x02) {
throw new IOException("Error: bad LDAP encoding in capture file: " +
"expected ASN.1 INTEGER tag (0x02), encountered " +
encoding[index]);
}
int length = encoding[index + 1];
index += 2;
int messageID =
new BigInteger(1,
Arrays.copyOfRange(encoding, index, index + length)).intValue();
index += length;
int operationID = encoding[index];
return new int[]{messageID, operationID};
}
/*
* Maps an LDAP operation ID to a string description
*/
private static String getOperation(int operationID) {
switch (operationID) {
case 0x60:
return "BindRequest"; // [APPLICATION 0]
case 0x61:
return "BindResponse"; // [APPLICATION 1]
case 0x42:
return "UnbindRequest"; // [APPLICATION 2]
case 0x63:
return "SearchRequest"; // [APPLICATION 3]
case 0x64:
return "SearchResultEntry"; // [APPLICATION 4]
case 0x65:
return "SearchResultDone"; // [APPLICATION 5]
case 0x66:
return "ModifyRequest"; // [APPLICATION 6]
case 0x67:
return "ModifyResponse"; // [APPLICATION 7]
case 0x68:
return "AddRequest"; // [APPLICATION 8]
case 0x69:
return "AddResponse"; // [APPLICATION 9]
case 0x4A:
return "DeleteRequest"; // [APPLICATION 10]
case 0x6B:
return "DeleteResponse"; // [APPLICATION 11]
case 0x6C:
return "ModifyDNRequest"; // [APPLICATION 12]
case 0x6D:
return "ModifyDNResponse"; // [APPLICATION 13]
case 0x6E:
return "CompareRequest"; // [APPLICATION 14]
case 0x6F:
return "CompareResponse"; // [APPLICATION 15]
case 0x50:
return "AbandonRequest"; // [APPLICATION 16]
case 0x73:
return "SearchResultReference"; // [APPLICATION 19]
case 0x77:
return "ExtendedRequest"; // [APPLICATION 23]
case 0x78:
return "ExtendedResponse"; // [APPLICATION 24]
case 0x79:
return "IntermediateResponse"; // [APPLICATION 25]
default:
return "Unknown";
}
}
}