peermanager/utils/BTPeerIDByteDecoder.java

/*
 * Created on Nov 12, 2003
 * Created by Alon Rohter
 * Copyright (C) 2003-2004 Alon Rohter, All Rights Reserved.
 * Copyright (C) 2003, 2004, 2005, 2006 Aelitis, 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * AELITIS, SAS au capital de 46,603.30 euros
 * 8 Allee Lenotre, La Grille Royale, 78600 Le Mesnil le Roi, France.
 * 
 */
package com.aelitis.azureus.core.peermanager.utils;

import org.gudy.azureus2.core3.internat.MessageText;
import org.gudy.azureus2.core3.util.AEDiagnostics;
import org.gudy.azureus2.core3.util.AEDiagnosticsLogger;
import org.gudy.azureus2.core3.util.ByteFormatter;
import org.gudy.azureus2.core3.util.Constants;
import org.gudy.azureus2.core3.util.Debug;

import java.io.*;
import java.util.HashSet;


/**
 * Used for identifying clients by their peerID.
 */
public class BTPeerIDByteDecoder {

        final static boolean LOG_UNKNOWN;

        static {
                String  prop = System.getProperty("log.unknown.peerids");
                LOG_UNKNOWN = prop == null || prop.equals("1");
        }

        private static String logUnknownClient0(byte[] peer_id_bytes) throws IOException {
                String text = new String(peer_id_bytes, 0, 20, Constants.BYTE_ENCODING);
                text = text.replace((char)12, (char)32);
                text = text.replace((char)10, (char)32);

                return "[" + text + "] " + ByteFormatter.encodeString(peer_id_bytes) + " ";
        }
        
        private static String asUTF8ByteString(String text) {
                try {
                        byte[] utf_bytes = text.getBytes(Constants.DEFAULT_ENCODING);
                        return ByteFormatter.encodeString(utf_bytes);
                }
                catch (UnsupportedEncodingException uee) {return "";}
        }
        
        private static HashSet logged_discrepancies = new HashSet();
        public static void logClientDiscrepancy(String peer_id_name, String handshake_name, String discrepancy, String protocol, byte[] peer_id) {
                if (!client_logging_allowed) {return;}
                
                // Generate the string used that we will log.
                String line_to_log = discrepancy + " [" + protocol + "]: ";
                line_to_log += "\"" + peer_id_name + "\" / \"" + handshake_name + "\" ";
                
                // We'll encode the name in byte form to help us decode it.
                line_to_log += "[" + asUTF8ByteString(handshake_name) + "]";
                
                // Avoid logging the same combination of things again.
                boolean log_to_debug_out = Constants.isCVSVersion();
                if (log_to_debug_out || LOG_UNKNOWN) {
                        // If this text has been recorded before, then avoid doing it again.
                        if (!logged_discrepancies.add(line_to_log)) {return;}
                }
                
                // Add peer ID bytes.
                if (peer_id != null) {
                        line_to_log += ", Peer ID: " + ByteFormatter.encodeString(peer_id);
                }
                
                // Enable this block for now - just until we get more feedback about
                // problematic clients.
                if (log_to_debug_out) {
                        Debug.outNoStack("Conflicting peer identification: " + line_to_log);
                }
                
                if (!LOG_UNKNOWN) {return;}
                logClientDiscrepancyToFile(line_to_log);
        }
        
        private static AEDiagnosticsLogger logger = null;
        private synchronized static void logClientDiscrepancyToFile(String line_to_log) {
                if (logger == null) {logger = AEDiagnostics.getLogger("clientid");}
                try {logger.log(line_to_log);}
                catch (Throwable e) {Debug.printStackTrace(e);}
        }
        
        static boolean client_logging_allowed = true;

        // I don't expect this to grow too big, and it won't grow if there's no logging going on.
        private static HashSet logged_ids = new HashSet();
        static void logUnknownClient(byte[] peer_id_bytes) {logUnknownClient(peer_id_bytes, true);}
        static void logUnknownClient(byte[] peer_id_bytes, boolean to_debug_out) {
                
                if (!client_logging_allowed) {return;}
                
                // Avoid logging the same client ID multiple times.
                boolean log_to_debug_out = to_debug_out && Constants.isCVSVersion();
                if (log_to_debug_out || LOG_UNKNOWN) {
                        // If the ID has been recorded before, then avoid doing it again.
                        if (!logged_ids.add(makePeerIDReadableAndUsable(peer_id_bytes))) {return;}
                }
                
                // Enable this block for now - just until we get more feedback about
                // unknown clients.
                if (log_to_debug_out) {
                        Debug.outNoStack("Unable to decode peer correctly - peer ID bytes: " + makePeerIDReadableAndUsable(peer_id_bytes));
                }
                
                if (!LOG_UNKNOWN) {return;}
                try {logClientDiscrepancyToFile(logUnknownClient0(peer_id_bytes));}
                catch (Throwable t) {Debug.printStackTrace(t);}
                
        }

        static void logUnknownClient(String peer_id) {
                try {logUnknownClient(peer_id.getBytes(Constants.BYTE_ENCODING));}
                catch (UnsupportedEncodingException uee) {}
        }

        public static String decode0(byte[] peer_id_bytes) {

                final String UNKNOWN = MessageText.getString("PeerSocket.unknown");
                final String FAKE = MessageText.getString("PeerSocket.fake_client");
                final String BAD_PEER_ID = MessageText.getString("PeerSocket.bad_peer_id");
                
                String peer_id = null;
                try {peer_id = new String(peer_id_bytes, Constants.BYTE_ENCODING);}
                catch (UnsupportedEncodingException uee) {return "";}

                // We store the result here.
                String client = null;

                /**
                 * If the client reuses parts of the peer ID of other peers, then try to determine this
                 * first (before we misidentify the client).
                 */
                if (BTPeerIDByteDecoderUtils.isPossibleSpoofClient(peer_id)) {
                        client = decodeBitSpiritClient(peer_id, peer_id_bytes);
                        if (client != null) {return client;}
                        client = decodeBitCometClient(peer_id, peer_id_bytes);
                        if (client != null) {return client;}
                        return "BitSpirit? (" + BAD_PEER_ID + ")";
                }

                /**
                 * See if the client uses Az style identification.
                 */
                if (BTPeerIDByteDecoderUtils.isAzStyle(peer_id)) {
                        client = BTPeerIDByteDecoderDefinitions.getAzStyleClientName(peer_id);
                        if (client != null) {
                                String client_with_version = BTPeerIDByteDecoderDefinitions.getAzStyleClientVersion(client, peer_id);

                                /**
                                 * Hack for fake ZipTorrent clients - there seems to be some clients
                                 * which use the same identifier, but they aren't valid ZipTorrent clients.
                                 */ 
                                if (client.startsWith("ZipTorrent") && peer_id.startsWith("bLAde", 8)) {
                                        String client_name = (client_with_version == null) ? client : client_with_version; 
                                        return UNKNOWN + " [" + FAKE  + ": " + client_name + "]";
                                }
                                
                                /**
                                 * BitTorrent 6.0 Beta currently misidentifies itself.
                                 */
                                if ("\u00B5Torrent 6.0.0 Beta".equals(client_with_version)) {
                                        return "Mainline 6.0 Beta";
                                }
                                
                                /**
                                 * If it's the rakshasa libtorrent, then it's probably rTorrent.
                                 */
                                if (client.startsWith("libTorrent (Rakshasa)")) {
                                        String client_name = (client_with_version == null) ? client : client_with_version;
                                        return client_name + " / rTorrent*";
                                }
                                
                                if (client_with_version != null) {return client_with_version;}
                                
                                return client;
                        }
                
                }

                /**
                 * See if the client uses Shadow style identification.
                 */
                if (BTPeerIDByteDecoderUtils.isShadowStyle(peer_id)) {
                        client = BTPeerIDByteDecoderDefinitions.getShadowStyleClientName(peer_id);
                        if (client != null) {
                                String client_ver = BTPeerIDByteDecoderUtils.getShadowStyleVersionNumber(peer_id);
                                if (client_ver != null) {return client + " " + client_ver;}
                                return client;
                        }
                }

                /**
                 * See if the client uses Mainline style identification.
                 */
                client = BTPeerIDByteDecoderDefinitions.getMainlineStyleClientName(peer_id);
                if (client != null) {
                        /**
                         * We haven't got a good way of detecting whether this is a Mainline style
                         * version of peer ID until we start decoding peer ID information. So for
                         * that reason, we wait until we get client version information here - if
                         * we don't manage to determine a version number, then we assume that it
                         * has been misidentified and carry on with it.
                         */
                        String client_ver = BTPeerIDByteDecoderUtils.getMainlineStyleVersionNumber(peer_id);
                        
                        if (client_ver != null) {
                                String result = client + " " + client_ver;
                                return result;
                        }
                }

                /**
                 * Check for BitSpirit / BitComet (non possible spoof client mode).
                 */
                client = decodeBitSpiritClient(peer_id, peer_id_bytes);
                if (client != null) {return client;}
                client = decodeBitCometClient(peer_id, peer_id_bytes);
                if (client != null) {return client;}


                /**
                 * See if the client identifies itself using a particular substring.
                 */
                BTPeerIDByteDecoderDefinitions.ClientData client_data = BTPeerIDByteDecoderDefinitions.getSubstringStyleClient(peer_id); 
                if (client_data != null) {
                        client = client_data.client_name;
                        String client_with_version = BTPeerIDByteDecoderDefinitions.getSubstringStyleClientVersion(client_data, peer_id, peer_id_bytes);
                        if (client_with_version != null) {return client_with_version;}
                        return client;
                }

                client = identifyAwkwardClient(peer_id_bytes);
                if (client != null) {return client;}
                return null;
        }

        /**
         * Decodes the given peerID, returning an identification string.
         */  
        public static String 
        decode(byte[] peer_id) 
        {
                if ( peer_id.length > 0 ){
                        
                        try {
                                String client = decode0(peer_id);
        
                                if (client != null ){
                                        
                                        return client;
                                }               
                        }catch (Throwable e) {
                                
                                Debug.out( "Failed to decode peer id " + ByteFormatter.encodeString(peer_id) + ": " + Debug.getNestedExceptionMessageAndStack( e ));
                        }
        
                        try {
                                String peer_id_as_string = new String(peer_id, Constants.BYTE_ENCODING);
                        
                                boolean is_az_style = BTPeerIDByteDecoderUtils.isAzStyle(peer_id_as_string);
                                
                                boolean is_shadow_style = BTPeerIDByteDecoderUtils.isShadowStyle(peer_id_as_string);
                                
                                logUnknownClient(peer_id, !(is_az_style || is_shadow_style));
                
                                if (is_az_style) {
                                        return BTPeerIDByteDecoderDefinitions.formatUnknownAzStyleClient(peer_id_as_string);
                                }
                                else if (is_shadow_style) {
                                        return BTPeerIDByteDecoderDefinitions.formatUnknownShadowStyleClient(peer_id_as_string);
                                }
                        }catch( Throwable e ){
                                
                                Debug.out( "Failed to decode peer id " + ByteFormatter.encodeString(peer_id) + ": " + Debug.getNestedExceptionMessageAndStack( e ));    
                        }
                }
                
                String sPeerID = getPrintablePeerID(peer_id);
                return MessageText.getString("PeerSocket.unknown") + " [" + sPeerID + "]";
        }

        public static String identifyAwkwardClient(byte[] peer_id) { 

                int iFirstNonZeroPos = 0;

                iFirstNonZeroPos = 20;
                for( int i=0; i < 20; i++ ) {
                        if( peer_id[i] != (byte)0 ) {
                                iFirstNonZeroPos = i;
                                break;
                        }
                }      

                //Shareaza check
                if( iFirstNonZeroPos == 0 ) {
                        boolean bShareaza = true;
                        for( int i=0; i < 16; i++ ) {
                                if( peer_id[i] == (byte)0 ) {
                                        bShareaza = false;
                                        break;
                                }
                        }
                        if( bShareaza ) {
                                for( int i=16; i < 20; i++ ) {
                                        if( peer_id[i] != ( peer_id[i % 16] ^ peer_id[15 - (i % 16)] ) ) {
                                                bShareaza = false;
                                                break;
                                        }
                                }
                                if( bShareaza )  return "Shareaza";
                        }
                }

                byte three = (byte)3;
                if ((iFirstNonZeroPos == 9)
                                && (peer_id[9] == three)
                                && (peer_id[10] == three)
                                && (peer_id[11] == three)) {
                        return "Snark";
                }

                if ((iFirstNonZeroPos == 12) && (peer_id[12] == (byte)97) && (peer_id[13] == (byte)97)) {
                        return "Experimental 3.2.1b2";
                }
                if ((iFirstNonZeroPos == 12) && (peer_id[12] == (byte)0) && (peer_id[13] == (byte)0)) {
                        return "Experimental 3.1";
                }
                if (iFirstNonZeroPos == 12) return "Mainline";

                return null;

        }

        private static String decodeBitSpiritClient(String peer_id, byte[] peer_id_bytes) {
                if (!peer_id.substring(2, 4).equals("BS")) {return null;}
                String version = BTPeerIDByteDecoderUtils.decodeNumericValueOfByte(peer_id_bytes[1]);
                if ("0".equals(version)) {version = "1";}
                return "BitSpirit v" + version;
        }

        private static String decodeBitCometClient(String peer_id, byte[] peer_id_bytes) {
                String mod_name = null;
                if (peer_id.startsWith("exbc")) {mod_name = "";}
                else if (peer_id.startsWith("FUTB")) {mod_name  = "(Solidox Mod) ";}
                else if (peer_id.startsWith("xUTB")) {mod_name  = "(Mod 2) ";}
                else {return null;}

                boolean is_bitlord = (peer_id.substring(6, 10).equals("LORD"));

                /**
                 * Older versions of BitLord are of the form x.yy, whereas new versions (1 and onwards),
                 * are of the form x.y. BitComet is of the form x.yy.
                 */
                String client_name = (is_bitlord) ? "BitLord " : "BitComet ";
                String maj_version = BTPeerIDByteDecoderUtils.decodeNumericValueOfByte(peer_id_bytes[4]);
                int min_version_length = (is_bitlord && !maj_version.equals("0")) ? 1 : 2;

                return client_name + mod_name + maj_version + "." +
                BTPeerIDByteDecoderUtils.decodeNumericValueOfByte(peer_id_bytes[5], min_version_length);          
        }


        protected static String getPrintablePeerID(byte[] peer_id) {
                return getPrintablePeerID(peer_id, '-');
        }
        
        protected static String getPrintablePeerID(byte[] peer_id, char fallback_char) {
                String  sPeerID = "";
                byte[] peerID = new byte[ peer_id.length ];
                System.arraycopy( peer_id, 0, peerID, 0, peer_id.length );

                try {
                        for (int i = 0; i < peerID.length; i++) {
                                int b = (0xFF & peerID[i]);
                                if (b < 32 || b > 127)
                                        peerID[i] = (byte)fallback_char;
                        }
                        sPeerID = new String(peerID, Constants.BYTE_ENCODING);
                }
                catch (UnsupportedEncodingException ignore) {}
                catch (Throwable e) {}

                return( sPeerID );
        }
        
        private static String makePeerIDReadableAndUsable(byte[] peer_id) {
                boolean as_ascii = true;
                for (int i=0; i<peer_id.length; i++) {
                        int b = 0xFF & peer_id[i];
                        if (b < 32 || b > 127 || b == 10 || b == 9 || b==13) {
                                as_ascii = false;
                                break;
                        }
                }
                if (as_ascii) {
                        try {return new String(peer_id, Constants.BYTE_ENCODING);}
                        catch (UnsupportedEncodingException uee) {return "";}
                }
                else {return ByteFormatter.encodeString(peer_id);}
        }
        
        static byte[] peerIDStringToBytes(String peer_id) throws Exception {
                if (peer_id.length() > 40) {
                        peer_id = peer_id.replaceAll("[ ]", "");
                }

                byte[] byte_peer_id = null;
                if (peer_id.length() == 40) {
                        byte_peer_id = ByteFormatter.decodeString(peer_id);
                        String readable_peer_id = makePeerIDReadableAndUsable(byte_peer_id);
                        if (!peer_id.equals(readable_peer_id)) {
                                throw new RuntimeException("Use alternative format for peer ID - from " + peer_id + " to " + readable_peer_id);
                        }
                }
                else if (peer_id.length() == 20) {
                        byte_peer_id = peer_id.getBytes(Constants.BYTE_ENCODING);
                }
                else {
                        throw new IllegalArgumentException(peer_id);
                }
                return byte_peer_id;
        }

        private static void assertDecode(String client_result, String peer_id) throws Exception {
                assertDecode(client_result, peerIDStringToBytes(peer_id));
        }
        
        private static void assertDecode(String client_result, byte[] peer_id) throws Exception {
                String peer_id_as_string = getPrintablePeerID(peer_id, '*');
                System.out.println("   Peer ID: " + peer_id_as_string + "   Client: " + client_result);
                
                // Do not log any clients.
                String decoded_result = decode(peer_id);
                if (client_result.equals(decoded_result)) {return;}
                throw new RuntimeException("assertion failure - expected \"" + client_result + "\", got \"" + decoded_result + "\": " + peer_id_as_string);
        }

        public static void main(String[] args) throws Exception {
                client_logging_allowed = false;
                
                final String FAKE = MessageText.getString("PeerSocket.fake_client");
                final String UNKNOWN = MessageText.getString("PeerSocket.unknown");
                final String BAD_PEER_ID = MessageText.getString("PeerSocket.bad_peer_id");
                
                System.out.println("Testing AZ style clients...");
                assertDecode("Ares 2.0.5.3", "-AG2053-Em6o1EmvwLtD");
                assertDecode("Ares 1.6.7.0", "-AR1670-3Ql6wM3hgtCc");
                assertDecode("Artemis 2.5.2.0", "-AT2520-vEEt0wO6v0cr");
                assertDecode("Azureus 2.2.0.0", "-AZ2200-6wfG2wk6wWLc");
                assertDecode("BT Next Evolution 1.0.9", "-NE1090002IKyMn4g7Ko");
                assertDecode("BitRocket 0.3(32)", "-BR0332-!XVceSn(*KIl");
                assertDecode("Mainline 6.0 Beta", "2D555436 3030422D A78DC290 C3F7BDE0 15EC3CC7");
                assertDecode("FlashGet 1.80", "2D464730 31383075 F8005782 1359D64B B3DFD265");
                assertDecode("GetRight 6.3", "-GR6300-13s3iFKmbArc");
                assertDecode("Halite 0.2.9", "-HL0290-xUO*9ugvENUE");
                assertDecode("KTorrent 1.1 RC1", "-KT11R1-693649213030");
                assertDecode("KTorrent 3.0", "2D4B543330302D006A7139727958377731756A4B");
                assertDecode("libTorrent (Rakshasa) 0.11.2 / rTorrent*", "2D6C74304232302D0D739B93E6BE21FEBB557B20");
                assertDecode("libtorrent (Rasterbar) 0.13.0", "-LT0D00-eZ0PwaDDr-~v"); // The latest version at time of writing is v0.12, but I'll assume this is valid.
                assertDecode("linkage 0.1.4", "-LK0140-ATIV~nbEQAMr");
                assertDecode("LimeWire", "2D4C57303030312D31E0B3A0B46F7D4E954F4103");
                assertDecode("Lphant 3.02", "2D4C5030 3330322D 00383336 35363935 37373030");
                assertDecode("Shareaza 2.1.3.2", "2D535A323133322D000000000000000000000000");
                assertDecode("SymTorrent 1.17", "-ST0117-01234567890!");
                assertDecode("Transmission 0.6", "-TR0006-01234567890!");
                assertDecode("Transmission 0.72 (Dev)", "-TR072Z-zihst5yvg22f");
                assertDecode("Transmission 0.72", "-TR0072-8vd6hrmp04an");
                assertDecode("TuoTu 2.1.0", "-TT210w-dq!nWf~Qcext");
                assertDecode("\u00B5Torrent 1.7.0 Beta", "2D555431 3730422D 92844644 1DB0A094 A01C01E5");
                assertDecode("\u54c7\u560E (Vagaa) 2.6.4.4", "2D5647323634342D4FD62CDA69E235717E3BB94B");
                assertDecode("Wyzo 0.3.0.0", "-WY0300-6huHF5Pr7Vde");
                assertDecode("CacheLogic 25.1-26", "-PC251Q-6huHF5Pr7Vde");
                System.out.println();

                // Shadow style clients.
                System.out.println("Testing Shadow style clients...");
                assertDecode("ABC", "A--------YMyoBPXYy2L"); // Seen this quite a bit - not sure that it is ABC, but I guess we should default to that...
                assertDecode("ABC 2.6.9", "413236392D2D2D2D345077199FAEC4A673BECA01");
                assertDecode("ABC 3.1", "A310--001v5Gysr4NxNK");
                assertDecode("BitTornado 0.3.12", "T03C-----6tYolxhVUFS");
                assertDecode("BitTornado 0.3.18", "T03I--008gY6iB6Aq27C");
                assertDecode("BitTornado 0.3.9", "T0390----5uL5NvjBe2z");
                assertDecode("Tribler 1", "R100--003hR6s07XWcov"); // Seen recently - is this really Tribler?
                assertDecode("Tribler 3.7", "R37---003uApHy851-Pq");
                System.out.println();

                // Simple substring style clients.
                System.out.println("Testing simple substring clients...");
                assertDecode("Azureus 1", "417A7572 65757300 00000000 000000A0 76F0AEF7");
                assertDecode("Azureus 2.0.3.2", "2D2D2D2D2D417A757265757354694E7A2A6454A7");
                assertDecode("G3 Torrent", "2D473341 6E6F6E79 6D6F7573 70E8D9CB 30250AD4");
                assertDecode("Hurricane Electric", "6172636C696768742E68652EA5860C157A5ADC35");
                assertDecode("Pando", "Pando-6B511B691CAC2E"); // Seen recently, have they changed peer ID format?
                assertDecode("\u00B5Torrent 1.7.0 RC", "2D55543137302D00AF8BC5ACCC4631481EB3EB60");
                System.out.println();
                
                // Version substring style clients.
                System.out.println("Testing versioned substring clients...");
                assertDecode("Bitlet 0.1", "4269744C657430319AEA4E02A09E318D70CCF47D");
                assertDecode("BitsOnWheels", "-BOWP05-EPICNZOGQPHP"); // Seen in the wild - no idea what version that's meant to be - a pre-release?
                assertDecode("Burst! 1.1.3", "Mbrst1-1-32e3c394b43");
                assertDecode("Opera (Build 7685)", "OP7685f2c1495b1680bf");
                assertDecode("Opera (Build 10063)", "O100634008270e29150a");
                assertDecode("Rufus 0.6.9", "00455253 416E6F6E 796D6F75 7382BE42 75024AE3");
                assertDecode("BitTorrent DNA 1.0", "444E413031303030DD01C9B2DA689E6E02803E91");
                assertDecode("BTuga Revolution 2.1", "BTM21abcdefghijklmno");
                assertDecode("AllPeers 0.70rc30", "4150302E3730726333302D3E3EB87B31F241DBFE"); // AP0.70rc30->>-{1-A--]"
                assertDecode("External Webseed", "45787420EC7CC30033D7801FEEB713FBB0557AC4");
                assertDecode("QVOD (Build 0054)", "QVOD00541234567890AB"); // Based on description on wiki.theory.org.
                assertDecode("Top-BT 1.0.0", "TB100----abcdefghijk");
                System.out.println();
                
                // BitComet/Lord/Spirit
                System.out.println("Testing BitComet/Lord/Spirit clients...");
                assertDecode("BitComet 0.56", "6578626300387A4463102D6E9AD6723B339F35A9");
                assertDecode("BitLord 0.56", "6578626300384C4F52443200048ECED57BD71028");
                assertDecode("BitSpirit? (" + BAD_PEER_ID + ")", "4D342D302D322D2D6898D9D0CAF25E4555445030");
                assertDecode("BitSpirit v2", "000242539B7ED3E058A8384AA748485454504254");
                assertDecode("BitSpirit v3", "00034253 07248896 44C59530 8A5FF2CA 55445030");
                System.out.println();

                // Mainline style clients.
                System.out.println("Testing new mainline style clients...");
                assertDecode("Mainline 5.0.7", "M5-0-7--9aa757efd5be");
                assertDecode("Amazon AWS S3", "S3-1-0-0--0123456789"); // Not currently decoded as mainline style...
                System.out.println();
                
                // Various specialised clients.
                System.out.println("Testing various specialised clients...");
                assertDecode("Mainline", "0000000000000000000000004C53441933104277");
                assertDecode(UNKNOWN + " [" + FAKE + ": ZipTorrent 1.6.0.0]", "-ZT1600-bLAdeY9rdjbe");
                System.out.println();
                
                // Unknown clients - may be random bytes.
                System.out.println("Testing unknown (random byte?) clients...");
                assertDecode(UNKNOWN + " [--------1}-/---A---<]", "0000000000000000317DA32F831FF041A515FE3C");
                assertDecode(UNKNOWN + " [------- --  ------@(]", "000000DF05020020100020200008000000004028");
                assertDecode(UNKNOWN + " [-----------D-y-I--aO]", "0000000000000000F106CE44F179A2498FAC614F");
                assertDecode(UNKNOWN + " [--c--_-5-\\----t-#---]", "E7F163BB0E5FCD35005C09A11BC274C42385A1A0");
                System.out.println();
                
                // Unknown AZ style clients.
                System.out.println("Testing unknown AZ style clients...");
                String unknown_az;
                unknown_az = MessageText.getString("PeerSocket.unknown_az_style", new String[]{"BD", "0.3.0.0"});
                assertDecode(unknown_az, "-BD0300-1SGiRZ8uWpWH");
                unknown_az = MessageText.getString("PeerSocket.unknown_az_style", new String[]{"wF", "2.2.0.0"});
                assertDecode(unknown_az, "2D7746323230302D9DFF296B56AFC2DF751C609C");
                unknown_az = MessageText.getString("PeerSocket.unknown_az_style", new String[]{"X1", "0.0.6.4"});
                assertDecode(unknown_az, "2D5831303036342D12FB8A5B954153A114267F1F");
                unknown_az = MessageText.getString("PeerSocket.unknown_az_style", new String[]{"bF", "2q00"}); // I made this one up.
                assertDecode(unknown_az, "2D6246327130302D9DFF296B56AFC2DF751C609C");
                System.out.println();
                
                // Unknown Shadow style clients.
                System.out.println("Testing unknown Shadow style clients...");
                String unknown_shadow;
                unknown_shadow = MessageText.getString("PeerSocket.unknown_shadow_style", new String[]{"B", "1.2"});
                assertDecode(unknown_shadow, "B12------xgTofhetSVQ");
                System.out.println();

                // TODO
                //assertDecode("KTorrent 2.2", "-KT22B1-695754334315"); // We could use the B1 information...
                //assertDecode("KTorrent 2.1.4", "-KT2140-584815613993"); // Currently shows as 2.1.
                //assertDecode("", "C8F2D9CD3A90455354426578626300362D2D2D92"); // Looks like a BitLord client - ESTBexbc?
                //assertDecode("", "303030302D2D0000005433585859684B59584C72"); // Seen in the wild, appears to be a modified version of Azureus 2.5.0.0 (that's what was in the AZMP handshake)?
                //assertDecode("", "B5546F7272656E742F3330323520202020202020");

                System.out.println("Done.");
        }
}