a4f80b3e7e
git-svn-id: http://libopenmetaverse.googlecode.com/svn/trunk@74 52acb1d6-8a22-11de-b505-999d5b087335
1073 lines
39 KiB
C#
1073 lines
39 KiB
C#
/*
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* SLProxy.cs: implementation of Second Life proxy library
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*
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* Copyright (c) 2006 Austin Jennings
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* All rights reserved.
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*
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* - Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions are met:
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*
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* - Redistributions of source code must retain the above copyright notice, this
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* list of conditions and the following disclaimer.
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* - Neither the name of the Second Life Reverse Engineering Team nor the names
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* of its contributors may be used to endorse or promote products derived from
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* this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*/
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using Nwc.XmlRpc;
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using System;
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using System.Collections;
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using System.IO;
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using System.Net;
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using System.Net.Sockets;
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using System.Text;
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using System.Text.RegularExpressions;
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using System.Threading;
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using System.Xml;
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using libsecondlife;
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// SLProxy: proxy library for Second Life
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namespace SLProxy {
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// ProxyConfig: configuration for proxy objects
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public class ProxyConfig {
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// userAgent: name of the proxy application
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public string userAgent;
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// author: email address of the proxy application's author
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public string author;
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// protocol: libsecondlife ProtocolManager
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public ProtocolManager protocol;
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// loginPort: port that the login proxy will listen on
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public ushort loginPort = 8080;
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// clientFacingAddress: address from which to communicate with the client
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public IPAddress clientFacingAddress = IPAddress.Loopback;
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// remoteFacingAddress: address from which to communicate with the server
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public IPAddress remoteFacingAddress = IPAddress.Any;
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// remoteLoginUri: URI for Second Life's login server
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public Uri remoteLoginUri = new Uri("https://login.agni.lindenlab.com/cgi-bin/login.cgi");
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// verbose: whether or not to print informative messages and warnings
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public bool verbose = true;
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// ProxyConfig: construct a default proxy configuration with the specified userAgent, author, and protocol
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public ProxyConfig(string userAgent, string author, ProtocolManager protocol) {
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this.userAgent = userAgent;
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this.author = author;
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this.protocol = protocol;
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}
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// ProxyConfig: construct a default proxy configuration, parsing command line arguments (try --proxy-help)
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public ProxyConfig(string userAgent, string author, ProtocolManager protocol, string[] args) : this(userAgent, author, protocol) {
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Hashtable argumentParsers = new Hashtable();
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argumentParsers["proxy-help"] = new ArgumentParser(ParseHelp);
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argumentParsers["proxy-login-port"] = new ArgumentParser(ParseLoginPort);
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argumentParsers["proxy-client-facing-address"] = new ArgumentParser(ParseClientFacingAddress);
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argumentParsers["proxy-remote-facing-address"] = new ArgumentParser(ParseRemoteFacingAddress);
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argumentParsers["proxy-remote-login-uri"] = new ArgumentParser(ParseRemoteLoginUri);
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argumentParsers["proxy-verbose"] = new ArgumentParser(ParseVerbose);
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argumentParsers["proxy-quiet"] = new ArgumentParser(ParseQuiet);
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foreach (string arg in args)
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foreach (string argument in argumentParsers.Keys) {
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Match match = (new Regex("^--" + argument + "(?:=(.*))?$")).Match(arg);
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if (match.Success) {
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string value;
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if (match.Groups[1].Captures.Count == 1)
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value = match.Groups[1].Captures[0].ToString();
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else
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value = null;
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try {
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((ArgumentParser)argumentParsers[argument])(value);
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} catch {
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Console.WriteLine("invalid value for --" + argument);
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ParseHelp(null);
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}
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}
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}
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}
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private delegate void ArgumentParser(string value);
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private void ParseHelp(string value) {
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Console.WriteLine("Proxy command-line arguments:" );
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Console.WriteLine(" --proxy-help display this help" );
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Console.WriteLine(" --proxy-login-port=<port> listen for logins on <port>" );
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Console.WriteLine(" --proxy-client-facing-address=<IP> communicate with client via <IP>" );
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Console.WriteLine(" --proxy-remote-facing-address=<IP> communicate with server via <IP>" );
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Console.WriteLine(" --proxy-remote-login-uri=<URI> use SL login server at <URI>" );
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Console.WriteLine(" --proxy-verbose display proxy notifications" );
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Console.WriteLine(" --proxy-quiet suppress proxy notifications" );
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Environment.Exit(1);
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}
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private void ParseLoginPort(string value) {
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loginPort = Convert.ToUInt16(value);
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}
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private void ParseClientFacingAddress(string value) {
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clientFacingAddress = IPAddress.Parse(value);
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}
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private void ParseRemoteFacingAddress(string value) {
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remoteFacingAddress = IPAddress.Parse(value);
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}
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private void ParseRemoteLoginUri(string value) {
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remoteLoginUri = new Uri(value);
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}
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private void ParseVerbose(string value) {
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if (value != null)
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throw new Exception();
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verbose = true;
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}
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private void ParseQuiet(string value) {
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if (value != null)
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throw new Exception();
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verbose = false;
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}
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}
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// Proxy: Second Life proxy server
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// A Proxy instance is only prepared to deal with one client at a time.
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public class Proxy {
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private ProxyConfig proxyConfig;
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/*
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* Proxy Management
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*/
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// Proxy: construct a proxy server with the given configuration
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public Proxy(ProxyConfig proxyConfig) {
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this.proxyConfig = proxyConfig;
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InitializeLoginProxy();
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InitializeSimProxy();
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}
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// Start: begin accepting clients
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public void Start() {
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RunSimProxy();
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(new Thread(new ThreadStart(RunLoginProxy))).Start();
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IPEndPoint endPoint = (IPEndPoint)loginServer.LocalEndPoint;
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IPAddress displayAddress;
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if (endPoint.Address == IPAddress.Any)
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displayAddress = IPAddress.Loopback;
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else
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displayAddress = endPoint.Address;
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Log("proxy ready at http://" + displayAddress + ":" + endPoint.Port + "/");
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}
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// SetLoginDelegate: specify a callback loginDelegate that will be called when the client logs in
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public void SetLoginDelegate(LoginDelegate loginDelegate) {
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this.loginDelegate = loginDelegate;
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}
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// AddDelegate: add callback packetDelegate for packets of type packetName going direction
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public void AddDelegate(string packetName, Direction direction, PacketDelegate packetDelegate) {
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Hashtable table = direction == Direction.Incoming ? incomingDelegates : outgoingDelegates;
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lock(table)
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table[packetName] = packetDelegate;
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}
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// RemoveDelegate: remove callback for packets of type packetName going direction
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public void RemoveDelegate(string packetName, Direction direction) {
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Hashtable table = direction == Direction.Incoming ? incomingDelegates : outgoingDelegates;
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lock(table)
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table.Remove(packetName);
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}
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// InjectPacket: send packet to the client or server when direction is Incoming or Outgoing, respectively
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public void InjectPacket(Packet packet, Direction direction) {
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if (activeCircuit == null) {
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// no active circuit; queue the packet for injection once we have one
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ArrayList queue = direction == Direction.Incoming ? queuedIncomingInjections : queuedOutgoingInjections;
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queue.Add(packet);
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} else {
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// tell the active sim proxy to inject the packet
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lock(activeCircuit) {
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SimProxy sim;
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lock(simProxies)
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sim = (SimProxy)simProxies[activeCircuit];
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sim.Inject(packet, direction);
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}
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}
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}
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// Log: write message to the console if in verbose mode
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private void Log(object message) {
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if (proxyConfig.verbose)
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Console.WriteLine(message);
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}
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/*
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* Login Proxy
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*/
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private Socket loginServer;
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// InitializeLoginProxy: initialize the login proxy
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private void InitializeLoginProxy() {
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loginServer = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
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loginServer.Bind(new IPEndPoint(proxyConfig.clientFacingAddress, proxyConfig.loginPort));
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loginServer.Listen(1);
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}
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// RunLoginProxy: process login requests from clients
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private void RunLoginProxy() {
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try {
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for (;;) {
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Socket client = loginServer.Accept();
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IPEndPoint clientEndPoint = (IPEndPoint)client.RemoteEndPoint;
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Log("handling login request from " + clientEndPoint);
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NetworkStream networkStream = new NetworkStream(client);
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StreamReader networkReader = new StreamReader(networkStream);
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StreamWriter networkWriter = new StreamWriter(networkStream);
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try {
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ProxyLogin(networkReader, networkWriter);
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} catch (Exception e) {
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Log("login failed: " + e.Message);
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}
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networkWriter.Close();
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networkReader.Close();
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networkStream.Close();
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client.Close();
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// send any packets queued for injection
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if (activeCircuit != null) {
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SimProxy activeProxy = (SimProxy)simProxies[activeCircuit];
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lock(queuedOutgoingInjections) {
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foreach (Packet packet in queuedOutgoingInjections)
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activeProxy.Inject(packet, Direction.Outgoing);
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queuedOutgoingInjections = new ArrayList();
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}
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}
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}
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} catch (Exception e) {
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Console.WriteLine(e.Message);
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Console.WriteLine(e.StackTrace);
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}
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}
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// ProxyLogin: proxy a login request
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private void ProxyLogin(StreamReader reader, StreamWriter writer) {
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string line;
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int contentLength = 0;
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// read HTTP header
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do {
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// read one line of the header
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line = reader.ReadLine();
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// check for premature EOF
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if (line == null)
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throw new Exception("EOF in client HTTP header");
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// look for Content-Length
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Match match = (new Regex(@"Content-Length: (\d+)$")).Match(line);
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if (match.Success)
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contentLength = Convert.ToInt32(match.Groups[1].Captures[0].ToString());
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} while (line != "");
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// read the HTTP body into a buffer
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char[] content = new char[contentLength];
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reader.Read(content, 0, contentLength);
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// convert the body into an XML-RPC request
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XmlRpcRequest request = (XmlRpcRequest)XmlRpcRequestDeserializer.Singleton.Deserialize(new String(content));
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// add our userAgent and author to the request
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Hashtable requestParams = new Hashtable();
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if (proxyConfig.userAgent != null)
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requestParams["user-agent"] = proxyConfig.userAgent;
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if (proxyConfig.author != null)
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requestParams["author"] = proxyConfig.author;
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request.Params.Add(requestParams);
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// forward the XML-RPC request to the server
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XmlRpcResponse response = (XmlRpcResponse)request.Send(proxyConfig.remoteLoginUri.ToString());
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Hashtable responseData = (Hashtable)response.Value;
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// proxy any simulator address given in the XML-RPC response
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if (responseData.Contains("sim_ip") && responseData.Contains("sim_port")) {
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IPEndPoint realSim = new IPEndPoint(IPAddress.Parse((string)responseData["sim_ip"]), Convert.ToUInt16(responseData["sim_port"]));
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IPEndPoint fakeSim = ProxySim(realSim);
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responseData["sim_ip"] = fakeSim.Address.ToString();
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responseData["sim_port"] = fakeSim.Port;
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activeCircuit = realSim;
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}
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// start a new proxy session
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Reset();
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// call the loginDelegate
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if (loginDelegate != null) {
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SessionInformation session = new SessionInformation();
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if (responseData.Contains("agent_id"))
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session.agentID = new LLUUID((string)responseData["agent_id"]);
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if (responseData.Contains("session_id"))
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session.sessionID = new LLUUID((string)responseData["session_id"]);
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try {
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loginDelegate(session);
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} catch (Exception e) {
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Log("exception in login delegate: " + e.Message);
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}
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}
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// forward the XML-RPC response to the client
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XmlTextWriter responseWriter = new XmlTextWriter(writer);
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XmlRpcResponseSerializer.Singleton.Serialize(responseWriter, response);
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responseWriter.Close();
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}
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/*
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* Sim Proxy
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*/
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private Socket simFacingSocket;
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private IPEndPoint activeCircuit = null;
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private Hashtable proxyEndPoints = new Hashtable();
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private Hashtable simProxies = new Hashtable();
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private Hashtable proxyHandlers = new Hashtable();
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private LoginDelegate loginDelegate = null;
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private Hashtable incomingDelegates = new Hashtable();
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private Hashtable outgoingDelegates = new Hashtable();
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private ArrayList queuedIncomingInjections = new ArrayList();
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private ArrayList queuedOutgoingInjections = new ArrayList();
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// initialize the sim proxy
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private void InitializeSimProxy() {
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InitializeAddressCheckers();
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simFacingSocket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
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simFacingSocket.Bind(new IPEndPoint(proxyConfig.remoteFacingAddress, 0));
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Reset();
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}
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// Reset: start a new session
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private void Reset() {
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foreach (SimProxy simProxy in simProxies.Values)
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simProxy.Reset();
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}
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private byte[] receiveBuffer = new byte[4096];
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private EndPoint remoteEndPoint = (EndPoint)new IPEndPoint(IPAddress.Any, 0);
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// start listening for packets from remote sims
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private void RunSimProxy() {
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simFacingSocket.BeginReceiveFrom(receiveBuffer, 0, receiveBuffer.Length, SocketFlags.None, ref remoteEndPoint, new AsyncCallback(ReceiveFromSim), null);
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}
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// packet received from a remote sim
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private void ReceiveFromSim(IAsyncResult ar) {
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try {
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// pause listening and get the length of the packet
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int length;
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lock(simFacingSocket)
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length = simFacingSocket.EndReceiveFrom(ar, ref remoteEndPoint);
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lock(proxyHandlers)
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if (proxyHandlers.Contains(remoteEndPoint)) {
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// find the proxy responsible for forwarding this packet
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SimProxy simProxy = (SimProxy)proxyHandlers[remoteEndPoint];
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// interpret the packet according to the SL protocol
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Packet packet = new Packet(receiveBuffer, length, proxyConfig.protocol);
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// check for ACKs we're waiting for
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packet = simProxy.CheckAcks(packet, Direction.Incoming);
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// modify sequence numbers to account for injections
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packet = simProxy.ModifySequence(packet, Direction.Incoming);
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// check the packet for addresses that need proxying
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if (incomingCheckers.Contains(packet.Layout.Name)) {
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Packet newPacket = ((AddressChecker)incomingCheckers[packet.Layout.Name])(packet);
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SwapPacket(packet, newPacket);
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packet = newPacket;
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}
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// pass the packet to any callback delegates
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lock(incomingDelegates)
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if (incomingDelegates.Contains(packet.Layout.Name)) {
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try {
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Packet newPacket = ((PacketDelegate)incomingDelegates[packet.Layout.Name])(packet, (IPEndPoint)remoteEndPoint);
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if (newPacket == null) {
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if ((packet.Data[0] & Helpers.MSG_RELIABLE) != 0)
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simProxy.Inject(SpoofAck(packet), Direction.Outgoing);
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if ((packet.Data[0] & Helpers.MSG_APPENDED_ACKS) !=0)
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packet = SeparateAck(packet);
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else
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packet = null;
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} else {
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bool oldReliable = (packet.Data[0] & Helpers.MSG_RELIABLE) != 0;
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bool newReliable = (newPacket.Data[0] & Helpers.MSG_RELIABLE) != 0;
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if (oldReliable && !newReliable)
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SendPacket(SpoofAck(packet), (IPEndPoint)remoteEndPoint);
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else if (!oldReliable && newReliable)
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simProxy.WaitForAck(packet, Direction.Incoming);
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SwapPacket(packet, newPacket);
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packet = newPacket;
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}
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} catch (Exception e) {
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Log("exception in incoming delegate: " + e.Message);
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}
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}
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if (packet != null)
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// forward the packet to the client via the appropriate fake sim endpoint
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simProxy.HandlePacket(packet);
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} else
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// ignore packets from unknown peers
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Log("dropping packet from " + remoteEndPoint);
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// resume listening
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lock(simFacingSocket)
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simFacingSocket.BeginReceiveFrom(receiveBuffer, 0, receiveBuffer.Length, SocketFlags.None, ref remoteEndPoint, new AsyncCallback(ReceiveFromSim), null);
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} catch (Exception e) {
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Console.WriteLine(e.Message);
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Console.WriteLine(e.StackTrace);
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}
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}
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// HandlePacket: forward a packet to a sim from our fake client endpoint
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private void HandlePacket(Packet packet, IPEndPoint endPoint, SimProxy proxy) {
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// check the packet for addresses that need proxying
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if (outgoingCheckers.Contains(packet.Layout.Name)) {
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Packet newPacket = ((AddressChecker)outgoingCheckers[packet.Layout.Name])(packet);
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SwapPacket(packet, newPacket);
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packet = newPacket;
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}
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// pass the packet to any callback delegates
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lock(outgoingDelegates)
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if (outgoingDelegates.Contains(packet.Layout.Name)) {
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try {
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Packet newPacket = ((PacketDelegate)outgoingDelegates[packet.Layout.Name])(packet, endPoint);
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if (newPacket == null) {
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if ((packet.Data[0] & Helpers.MSG_RELIABLE) != 0)
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proxy.Inject(SpoofAck(packet), Direction.Incoming);
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if ((packet.Data[0] & Helpers.MSG_APPENDED_ACKS) != 0)
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packet = SeparateAck(packet);
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else
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packet = null;
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} else {
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bool oldReliable = (packet.Data[0] & Helpers.MSG_RELIABLE) != 0;
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bool newReliable = (newPacket.Data[0] & Helpers.MSG_RELIABLE) != 0;
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if (oldReliable && !newReliable)
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proxy.SendPacket(SpoofAck(packet));
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else if (!oldReliable && newReliable)
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proxy.WaitForAck(packet, Direction.Outgoing);
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SwapPacket(packet, newPacket);
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packet = newPacket;
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}
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} catch (Exception e) {
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Log("exception in outgoing delegate: " + e.Message);
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}
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}
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if (packet != null)
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// send the packet
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SendPacket(packet, endPoint);
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}
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// SendPacket: send a packet to a sim from our fake client endpoint
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public void SendPacket(Packet packet, IPEndPoint endPoint) {
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lock(simFacingSocket)
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|
simFacingSocket.SendTo(packet.Data, packet.Data.Length, SocketFlags.None, endPoint);
|
|
}
|
|
|
|
// SpoofAck: create an ACK for the given packet
|
|
private Packet SpoofAck(Packet packet) {
|
|
Hashtable blocks = new Hashtable();
|
|
Hashtable fields = new Hashtable();
|
|
fields["ID"] = (uint)packet.Sequence;
|
|
blocks[fields] = "Packets";
|
|
return PacketBuilder.BuildPacket("PacketAck", proxyConfig.protocol, blocks, 0);
|
|
}
|
|
|
|
// SeparateAck: create a standalone PacketAck for packet's appended ACKs
|
|
private Packet SeparateAck(Packet packet) {
|
|
int ackCount = ((packet.Data[0] & Helpers.MSG_APPENDED_ACKS) == 0 ? 0 : (int)packet.Data[packet.Data.Length - 1]);
|
|
Hashtable blocks = new Hashtable();
|
|
for (int i = 0; i < ackCount; ++i) {
|
|
Hashtable fields = new Hashtable();
|
|
int offset = packet.Data.Length - (ackCount - i) * 4 - 1;
|
|
fields["ID"] = (int)
|
|
(packet.Data[offset++] << 0)
|
|
+ (packet.Data[offset++] << 8)
|
|
+ (packet.Data[offset++] << 16)
|
|
+ (packet.Data[offset++] << 24)
|
|
;
|
|
blocks[fields] = "Packets";
|
|
}
|
|
|
|
Packet ack = PacketBuilder.BuildPacket("PacketAck", proxyConfig.protocol, blocks, 0);
|
|
ack.Sequence = packet.Sequence;
|
|
return ack;
|
|
}
|
|
|
|
// SwapPacket: copy the sequence number and appended ACKs from one packet to another
|
|
private static void SwapPacket(Packet oldPacket, Packet newPacket) {
|
|
newPacket.Sequence = oldPacket.Sequence;
|
|
|
|
int oldAcks = (oldPacket.Data[0] & Helpers.MSG_APPENDED_ACKS) == 0 ? 0 : (int)oldPacket.Data[oldPacket.Data.Length - 1];
|
|
int newAcks = (newPacket.Data[0] & Helpers.MSG_APPENDED_ACKS) == 0 ? 0 : (int)newPacket.Data[newPacket.Data.Length - 1];
|
|
|
|
if (oldAcks != 0 || newAcks != 0) {
|
|
int oldAckSize = oldAcks == 0 ? 0 : oldAcks * 4 + 1;
|
|
int newAckSize = newAcks == 0 ? 0 : newAcks * 4 + 1;
|
|
|
|
byte[] newData = new byte[newPacket.Data.Length - newAckSize + oldAckSize];
|
|
Array.Copy(newPacket.Data, 0, newData, 0, newPacket.Data.Length - newAckSize);
|
|
|
|
if (newAcks != 0)
|
|
newData[0] ^= Helpers.MSG_APPENDED_ACKS;
|
|
|
|
if (oldAcks != 0) {
|
|
newData[0] |= Helpers.MSG_APPENDED_ACKS;
|
|
Array.Copy(oldPacket.Data, oldPacket.Data.Length - oldAckSize, newData, newPacket.Data.Length - newAckSize, oldAckSize);
|
|
}
|
|
|
|
newPacket.Data = newData;
|
|
}
|
|
}
|
|
|
|
// ProxySim: return the proxy for the specified sim, creating it if it doesn't exist
|
|
private IPEndPoint ProxySim(IPEndPoint simEndPoint) {
|
|
lock(proxyEndPoints)
|
|
if (proxyEndPoints.Contains(simEndPoint))
|
|
// return the existing proxy
|
|
return (IPEndPoint)proxyEndPoints[simEndPoint];
|
|
else {
|
|
// return a new proxy
|
|
SimProxy simProxy = new SimProxy(proxyConfig, simEndPoint, this);
|
|
IPEndPoint fakeSim = simProxy.LocalEndPoint();
|
|
Log("creating proxy for " + simEndPoint + " at " + fakeSim);
|
|
simProxy.Run();
|
|
proxyEndPoints.Add(simEndPoint, fakeSim);
|
|
simProxies.Add(simEndPoint, simProxy);
|
|
return fakeSim;
|
|
}
|
|
}
|
|
|
|
// AddHandler: remember which sim proxy corresponds to a given sim
|
|
private void AddHandler(EndPoint endPoint, SimProxy proxy) {
|
|
lock(proxyHandlers)
|
|
proxyHandlers.Add(endPoint, proxy);
|
|
}
|
|
|
|
// SimProxy: proxy for a single simulator
|
|
private class SimProxy {
|
|
private ProxyConfig proxyConfig;
|
|
private IPEndPoint remoteEndPoint;
|
|
private Proxy proxy;
|
|
private Socket socket;
|
|
private object sequenceLock = new Object();
|
|
private ushort incomingSequence;
|
|
private ushort outgoingSequence;
|
|
private ArrayList incomingInjections;
|
|
private ArrayList outgoingInjections;
|
|
private Hashtable incomingAcks;
|
|
private Hashtable outgoingAcks;
|
|
|
|
// SimProxy: construct a proxy for a single simulator
|
|
public SimProxy(ProxyConfig proxyConfig, IPEndPoint simEndPoint, Proxy proxy) {
|
|
this.proxyConfig = proxyConfig;
|
|
remoteEndPoint = new IPEndPoint(simEndPoint.Address, simEndPoint.Port);
|
|
this.proxy = proxy;
|
|
socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
|
|
socket.Bind(new IPEndPoint(proxyConfig.clientFacingAddress, 0));
|
|
proxy.AddHandler(remoteEndPoint, this);
|
|
Reset();
|
|
}
|
|
|
|
// Reset: start a new session
|
|
public void Reset() {
|
|
lock(sequenceLock) {
|
|
incomingSequence = 0;
|
|
outgoingSequence = 0;
|
|
incomingInjections = new ArrayList();
|
|
outgoingInjections = new ArrayList();
|
|
incomingAcks = new Hashtable();
|
|
outgoingAcks = new Hashtable();
|
|
}
|
|
}
|
|
|
|
// ResendPackets: resend packets that haven't been ACKed
|
|
private void ResendPackets() {
|
|
try {
|
|
for (;;Thread.Sleep(1000))
|
|
lock(sequenceLock) {
|
|
foreach (Packet packet in incomingAcks.Values) {
|
|
packet.Data[0] |= Helpers.MSG_RESENT;
|
|
SendPacket(packet);
|
|
}
|
|
|
|
foreach (Packet packet in outgoingAcks.Values) {
|
|
packet.Data[0] |= Helpers.MSG_RESENT;
|
|
proxy.SendPacket(packet, remoteEndPoint);
|
|
}
|
|
}
|
|
} catch (Exception e) {
|
|
Console.WriteLine(e.Message);
|
|
Console.WriteLine(e.StackTrace);
|
|
}
|
|
}
|
|
|
|
// return the endpoint that the client should communicate with
|
|
public IPEndPoint LocalEndPoint() {
|
|
lock(socket)
|
|
return (IPEndPoint)socket.LocalEndPoint;
|
|
}
|
|
|
|
private byte[] receiveBuffer = new byte[4096];
|
|
private EndPoint clientEndPoint = new IPEndPoint(IPAddress.Any, 0);
|
|
bool firstReceive = true;
|
|
|
|
// Run: forward packets from the client to the sim
|
|
public void Run() {
|
|
(new Thread(new ThreadStart(ResendPackets))).Start();
|
|
socket.BeginReceiveFrom(receiveBuffer, 0, receiveBuffer.Length, SocketFlags.None, ref clientEndPoint, new AsyncCallback(ReceiveFromClient), null);
|
|
}
|
|
|
|
// ReceiveFromClient: packet received from the client
|
|
private void ReceiveFromClient(IAsyncResult ar) {
|
|
try {
|
|
// pause listening and fetch the packet
|
|
int length;
|
|
lock(clientEndPoint)
|
|
lock(socket)
|
|
length = socket.EndReceiveFrom(ar, ref clientEndPoint);
|
|
Packet packet = new Packet(receiveBuffer, length, proxyConfig.protocol);
|
|
|
|
// keep track of sequence numbers
|
|
lock(sequenceLock)
|
|
if (packet.Sequence > incomingSequence)
|
|
incomingSequence = packet.Sequence;
|
|
|
|
// look for ACKs we're waiting for
|
|
packet = CheckAcks(packet, Direction.Outgoing);
|
|
|
|
// modify sequence numbers to account for injections
|
|
packet = ModifySequence(packet, Direction.Outgoing);
|
|
|
|
// forward packet via our fake client endpoint
|
|
proxy.HandlePacket(packet, remoteEndPoint, this);
|
|
|
|
// send any packets queued for injection
|
|
if (firstReceive) {
|
|
firstReceive = false;
|
|
lock(proxy.queuedIncomingInjections) {
|
|
foreach (Packet queuedPacket in proxy.queuedIncomingInjections)
|
|
Inject(queuedPacket, Direction.Incoming);
|
|
proxy.queuedIncomingInjections = new ArrayList();
|
|
}
|
|
}
|
|
|
|
// resume listening
|
|
lock(clientEndPoint)
|
|
lock(socket)
|
|
socket.BeginReceiveFrom(receiveBuffer, 0, receiveBuffer.Length, SocketFlags.None, ref clientEndPoint, new AsyncCallback(ReceiveFromClient), null);
|
|
} catch (Exception e) {
|
|
Console.WriteLine(e.Message);
|
|
Console.WriteLine(e.StackTrace);
|
|
}
|
|
}
|
|
|
|
// HandlePacket: forward a packet from the sim to the client via our fake sim endpoint
|
|
public void HandlePacket(Packet packet) {
|
|
// keep track of sequence numbers
|
|
lock(sequenceLock)
|
|
if (packet.Sequence > outgoingSequence)
|
|
outgoingSequence = packet.Sequence;
|
|
|
|
// send the packet
|
|
SendPacket(packet);
|
|
}
|
|
|
|
// SendPacket: send a packet from the sim to the client via our fake sim endpoint
|
|
public void SendPacket(Packet packet) {
|
|
lock(clientEndPoint)
|
|
lock(socket)
|
|
socket.SendTo(packet.Data, packet.Data.Length, SocketFlags.None, clientEndPoint);
|
|
}
|
|
|
|
// Inject: inject a packet
|
|
public void Inject(Packet packet, Direction direction) {
|
|
lock(sequenceLock) {
|
|
if (direction == Direction.Incoming) {
|
|
if (firstReceive) {
|
|
lock(proxy.queuedIncomingInjections)
|
|
proxy.queuedIncomingInjections.Add(packet);
|
|
return;
|
|
}
|
|
|
|
incomingInjections.Add(++incomingSequence);
|
|
packet.Sequence = incomingSequence;
|
|
} else {
|
|
outgoingInjections.Add(++outgoingSequence);
|
|
packet.Sequence = outgoingSequence;
|
|
}
|
|
}
|
|
|
|
if ((packet.Data[0] & Helpers.MSG_RELIABLE) != 0)
|
|
WaitForAck(packet, direction);
|
|
|
|
if (direction == Direction.Incoming) {
|
|
lock (clientEndPoint)
|
|
lock (socket)
|
|
socket.SendTo(packet.Data, packet.Data.Length, SocketFlags.None, clientEndPoint);
|
|
} else
|
|
proxy.SendPacket(packet, remoteEndPoint);
|
|
}
|
|
|
|
// WaitForAck: take care of resending a packet until it's ACKed
|
|
public void WaitForAck(Packet packet, Direction direction) {
|
|
lock(sequenceLock) {
|
|
Hashtable table = direction == Direction.Incoming ? incomingAcks : outgoingAcks;
|
|
table.Add(packet.Sequence, packet);
|
|
}
|
|
}
|
|
|
|
// CheckAcks: check for and remove ACKs of packets we've injected
|
|
public Packet CheckAcks(Packet packet, Direction direction) {
|
|
lock(sequenceLock) {
|
|
Hashtable acks = direction == Direction.Incoming ? outgoingAcks : incomingAcks;
|
|
|
|
if (acks.Count == 0)
|
|
return packet;
|
|
|
|
// check for embedded ACKs
|
|
if (packet.Layout.Name == "PacketAck") {
|
|
bool changed = false;
|
|
Hashtable blocks = PacketUtility.Unbuild(packet);
|
|
Hashtable newBlocks = new Hashtable();
|
|
foreach (Hashtable fields in blocks.Keys) {
|
|
ushort id = (ushort)((uint)fields["ID"]);
|
|
if (acks.Contains(id)) {
|
|
acks.Remove(id);
|
|
changed = true;
|
|
} else
|
|
newBlocks.Add(fields, blocks[fields]);
|
|
}
|
|
if (changed) {
|
|
Packet newPacket = PacketBuilder.BuildPacket("PacketAck", proxyConfig.protocol, newBlocks, packet.Data[0]);
|
|
SwapPacket(packet, newPacket);
|
|
packet = newPacket;
|
|
}
|
|
}
|
|
|
|
// check for appended ACKs
|
|
if ((packet.Data[0] & Helpers.MSG_APPENDED_ACKS) != 0) {
|
|
byte ackCount = packet.Data[packet.Data.Length - 1];
|
|
for (int i = 0; i < ackCount;) {
|
|
int offset = packet.Data.Length - (ackCount - i) * 4 - 1;
|
|
ushort ackID = (ushort)(packet.Data[offset] + (packet.Data[offset + 1] << 8));
|
|
if (acks.Contains(ackID)) {
|
|
byte[] newData = new byte[packet.Data.Length - 4];
|
|
Array.Copy(packet.Data, 0, newData, 0, offset);
|
|
Array.Copy(packet.Data, offset + 4, newData, offset, packet.Data.Length - offset - 4);
|
|
--newData[newData.Length - 1];
|
|
packet.Data = newData;
|
|
--ackCount;
|
|
} else
|
|
++i;
|
|
}
|
|
if (ackCount == 0) {
|
|
byte[] newData = new byte[packet.Data.Length - 1];
|
|
Array.Copy(packet.Data, 0, newData, 0, packet.Data.Length - 1);
|
|
newData[0] ^= Helpers.MSG_APPENDED_ACKS;
|
|
packet.Data = newData;
|
|
}
|
|
}
|
|
}
|
|
|
|
return packet;
|
|
}
|
|
|
|
// ModifySequence: modify a packet's sequence number and ACK IDs to account for injections
|
|
public Packet ModifySequence(Packet packet, Direction direction) {
|
|
// TODO: after a period of time, roll injections into a base offset to avoid unbounded memory consumption.
|
|
|
|
lock(sequenceLock) {
|
|
ArrayList ourInjections = direction == Direction.Outgoing ? outgoingInjections : incomingInjections;
|
|
ArrayList theirInjections = direction == Direction.Incoming ? outgoingInjections : incomingInjections;
|
|
|
|
if (ourInjections.Count != 0) {
|
|
ushort newSequence = packet.Sequence;
|
|
foreach (ushort injection in ourInjections)
|
|
if (newSequence >= injection)
|
|
++newSequence;
|
|
packet.Sequence = newSequence;
|
|
}
|
|
|
|
if (theirInjections.Count != 0) {
|
|
if ((packet.Data[0] & Helpers.MSG_APPENDED_ACKS) != 0) {
|
|
int ackCount = packet.Data[packet.Data.Length - 1];
|
|
for (int i = 0; i < ackCount; ++i) {
|
|
int offset = packet.Data.Length - (ackCount - i) * 4 - 2;
|
|
uint ackID = (uint)(packet.Data[offset] + (packet.Data[offset + 1] << 8));
|
|
for (int j = theirInjections.Count - 1; j >= 0; --j)
|
|
if (ackID >= (ushort)theirInjections[j])
|
|
--ackID;
|
|
packet.Data[offset + 0] = (byte)(ackID % 256); ackID >>= 8;
|
|
packet.Data[offset + 1] = (byte)(ackID % 256); ackID >>= 8;
|
|
packet.Data[offset + 2] = (byte)(ackID % 256); ackID >>= 8;
|
|
packet.Data[offset + 3] = (byte)(ackID % 256); ackID >>= 8;
|
|
}
|
|
}
|
|
|
|
if (packet.Layout.Name == "PacketAck") {
|
|
Hashtable blocks = PacketUtility.Unbuild(packet);
|
|
foreach (Hashtable fields in blocks.Keys) {
|
|
if ((string)blocks[fields] == "Packets") {
|
|
uint ackID = (uint)fields["ID"];
|
|
for (int i = theirInjections.Count - 1; i >= 0; --i)
|
|
if (ackID >= (ushort)theirInjections[i])
|
|
--ackID;
|
|
fields["ID"] = ackID;
|
|
}
|
|
}
|
|
Packet newPacket = PacketBuilder.BuildPacket("PacketAck", proxyConfig.protocol, blocks, packet.Data[0]);
|
|
SwapPacket(packet, newPacket);
|
|
packet = newPacket;
|
|
}
|
|
}
|
|
}
|
|
|
|
return packet;
|
|
}
|
|
}
|
|
|
|
delegate Packet AddressChecker(Packet packet);
|
|
|
|
Hashtable incomingCheckers = new Hashtable();
|
|
Hashtable outgoingCheckers = new Hashtable();
|
|
|
|
// InitializeAddressCheckers: initialize delegates that check packets for addresses that need proxying
|
|
private void InitializeAddressCheckers() {
|
|
// TODO: Packets that I've never seen that appear to
|
|
// require checking are considered unhandled; these
|
|
// should be checked in a stable release. Packets that
|
|
// I've never seen that contain an IP and don't appear
|
|
// to require checking are considered mystery; these
|
|
// should be ignored in a stable release. Packets that
|
|
// are checked are considered unexpected if they come
|
|
// in the wrong direction; these should be ignored in a
|
|
// stable release.
|
|
AddChecker("SimulatorAssign", Direction.Incoming, new AddressChecker(LogUnhandledPacket));
|
|
AddChecker("SimulatorStart", Direction.Incoming, new AddressChecker(LogUnhandledPacket));
|
|
AddChecker("SimulatorPresentAtLocation", Direction.Incoming, new AddressChecker(LogUnhandledPacket));
|
|
AddChecker("RegionPresenceResponse", Direction.Incoming, new AddressChecker(LogUnhandledPacket));
|
|
AddChecker("AgentPresenceResponse", Direction.Incoming, new AddressChecker(LogUnhandledPacket));
|
|
AddMystery("TrackAgentSession");
|
|
AddMystery("ClearAgentSessions");
|
|
AddChecker("LogFailedMoneyTransaction", Direction.Incoming, new AddressChecker(LogUnhandledPacket));
|
|
AddMystery("DirFindQueryBackend");
|
|
AddMystery("DirPeopleQueryBackend");
|
|
AddMystery("OnlineStatusRequest");
|
|
AddChecker("SpaceLocationTeleportReply", Direction.Incoming, new AddressChecker(LogUnhandledPacket));
|
|
AddChecker("TeleportFinish", Direction.Incoming, new AddressChecker(CheckTeleportFinish));
|
|
AddMystery("AddModifyAbility");
|
|
AddMystery("RemoveModifyAbility");
|
|
AddMystery("ViewerStats");
|
|
AddChecker("EnableSimulator", Direction.Incoming, new AddressChecker(CheckEnableSimulator));
|
|
AddMystery("KickUser");
|
|
AddMystery("LogLogin");
|
|
AddMystery("DataServerLogout");
|
|
AddMystery("RequestLocationGetAccess");
|
|
AddMystery("RequestLocationGetAccessReply");
|
|
AddMystery("FindAgent");
|
|
AddMystery("RoutedMoneyBalanceReply");
|
|
AddChecker("UserLoginLocationReply", Direction.Incoming, new AddressChecker(LogUnhandledPacket));
|
|
AddChecker("SpaceLoginLocationReply", Direction.Incoming, new AddressChecker(LogUnhandledPacket));
|
|
AddMystery("RemoveMemeberFromGroup");
|
|
AddMystery("RpcScriptRequestInboundForward");
|
|
AddMystery("MailPingBounce");
|
|
AddMystery("OpenCircuit");
|
|
AddChecker("ClosestSimulator", Direction.Incoming, new AddressChecker(LogUnhandledPacket));
|
|
AddChecker("CrossedRegion", Direction.Incoming, new AddressChecker(CheckCrossedRegion));
|
|
AddChecker("NeighborList", Direction.Incoming, new AddressChecker(LogUnhandledPacket));
|
|
AddChecker("AgentToNewRegion", Direction.Incoming, new AddressChecker(LogUnhandledPacket));
|
|
}
|
|
|
|
// AddChecker: add a checker delegate
|
|
private void AddChecker(String name, Direction direction, AddressChecker checker) {
|
|
(direction == Direction.Incoming ? incomingCheckers : outgoingCheckers).Add(name, checker);
|
|
(direction == Direction.Incoming ? outgoingCheckers : incomingCheckers).Add(name, new AddressChecker(LogUnexpectedPacket));
|
|
}
|
|
|
|
// AddMystery: add a checker delegate that logs packets we're watching for development purposes
|
|
private void AddMystery(String name) {
|
|
incomingCheckers.Add(name, new AddressChecker(LogIncomingMysteryPacket));
|
|
outgoingCheckers.Add(name, new AddressChecker(LogOutgoingMysteryPacket));
|
|
}
|
|
|
|
// GenericCheck: replace the sim address in a packet with our proxy address
|
|
private Packet GenericCheck(Packet packet, string block, string fieldIP, string fieldPort, bool active) {
|
|
Hashtable blocks = PacketUtility.Unbuild(packet);
|
|
|
|
IPEndPoint realSim = new IPEndPoint((IPAddress)PacketUtility.GetField(blocks, block, fieldIP), Convert.ToInt32(PacketUtility.GetField(blocks, block, fieldPort)));
|
|
IPEndPoint fakeSim = ProxySim(realSim);
|
|
PacketUtility.SetField(blocks, block, fieldIP, fakeSim.Address);
|
|
PacketUtility.SetField(blocks, block, fieldPort, (ushort)fakeSim.Port);
|
|
|
|
if (active)
|
|
activeCircuit = realSim;
|
|
|
|
return PacketBuilder.BuildPacket(packet.Layout.Name, proxyConfig.protocol, blocks, packet.Data[0]);
|
|
}
|
|
|
|
// CheckTeleportFinish: check TeleportFinish packets
|
|
private Packet CheckTeleportFinish(Packet packet) {
|
|
return GenericCheck(packet, "Info", "SimIP", "SimPort", true);
|
|
}
|
|
|
|
// CheckEnableSimulator: check EnableSimulator packets
|
|
private Packet CheckEnableSimulator(Packet packet) {
|
|
return GenericCheck(packet, "SimulatorInfo", "IP", "Port", false);
|
|
}
|
|
|
|
// CheckCrossedregion: check CrossedRegion packets
|
|
private Packet CheckCrossedRegion(Packet packet) {
|
|
return GenericCheck(packet, "RegionData", "SimIP", "SimPort", true);
|
|
}
|
|
|
|
// LogPacket: log a packet dump
|
|
private Packet LogPacket(Packet packet, string type) {
|
|
Log(type + " packet:");
|
|
Log(packet);
|
|
|
|
return packet;
|
|
}
|
|
|
|
// LogUnhandledPacket: log a packet that probably ought to have been checked
|
|
private Packet LogUnhandledPacket(Packet packet) {
|
|
return LogPacket(packet, "unhandled");
|
|
}
|
|
|
|
// LogUnexpectedPacket: log a packet that we expected to be going the opposite direction
|
|
private Packet LogUnexpectedPacket(Packet packet) {
|
|
return LogPacket(packet, "unexpected");
|
|
}
|
|
|
|
// LogIncomingMysteryPacket: log an incoming packet we're watching for development purposes
|
|
private Packet LogIncomingMysteryPacket(Packet packet) {
|
|
return LogPacket(packet, "incoming mystery");
|
|
}
|
|
|
|
// LogOutgoingMysteryPacket: log an outgoing packet we're watching for development purposes
|
|
private Packet LogOutgoingMysteryPacket(Packet packet) {
|
|
return LogPacket(packet, "outgoing mystery");
|
|
}
|
|
}
|
|
|
|
// LoginDelegate: specifies a delegate to be called when the client logs in
|
|
public delegate void LoginDelegate(SessionInformation session);
|
|
|
|
// PacketDelegate: specifies a delegate to be called when a packet passes through the proxy
|
|
public delegate Packet PacketDelegate(Packet packet, IPEndPoint endPoint);
|
|
|
|
// SessionInformation: contains information about a Second Life session
|
|
public class SessionInformation {
|
|
public LLUUID agentID;
|
|
public LLUUID sessionID;
|
|
}
|
|
|
|
// Direction: specifies whether a packet is going to the client (Incoming) or to a sim (Outgoing)
|
|
public enum Direction {
|
|
Incoming,
|
|
Outgoing
|
|
}
|
|
|
|
// PacketUtility: provides various utility methods for working with libsecondlife Packet objects
|
|
public class PacketUtility {
|
|
// Unbuild: deconstruct a packet into a Hashtable of blocks suitable for passing to PacketBuilder
|
|
public static Hashtable Unbuild(Packet packet) {
|
|
Hashtable blockTable = new Hashtable();
|
|
foreach (Block block in packet.Blocks()) {
|
|
Hashtable fieldTable = new Hashtable();
|
|
foreach (Field field in block.Fields)
|
|
fieldTable[field.Layout.Name] = field.Data;
|
|
blockTable[fieldTable] = block.Layout.Name;
|
|
}
|
|
|
|
return blockTable;
|
|
}
|
|
|
|
// GetField: given a table of blocks, return the value of the specified block and field
|
|
// In the case of packets with variable blocks, an arbitrary block will be used.
|
|
public static object GetField(Hashtable blocks, string block, string field) {
|
|
foreach (Hashtable fields in blocks.Keys)
|
|
if ((string)blocks[fields] == block)
|
|
if (fields.Contains(field))
|
|
return fields[field];
|
|
|
|
return null;
|
|
}
|
|
|
|
// SetField: given a table of blocks, update the value of the specified block and field
|
|
// In the case of packets with variable blocks, all blocks will be updated.
|
|
public static void SetField(Hashtable blocks, string block, string field, object value) {
|
|
foreach (Hashtable fields in blocks.Keys)
|
|
if ((string)blocks[fields] == block)
|
|
if (fields.Contains(field))
|
|
fields[field] = value;
|
|
}
|
|
|
|
// VariableToString: convert a variable field to a string
|
|
// Returns an empty string if the field can't be decoded as UTF-8
|
|
public static string VariableToString(byte[] field) {
|
|
try {
|
|
byte[] withoutNull = new byte[field.Length - 1];
|
|
Array.Copy(field, 0, withoutNull, 0, field.Length - 1);
|
|
return System.Text.Encoding.UTF8.GetString(withoutNull);
|
|
} catch {
|
|
return "";
|
|
}
|
|
}
|
|
|
|
// StringtoVariable: convert a string to a variable field
|
|
// Returns an empty field if the string can't be encoded as UTF-8
|
|
public static byte[] StringToVariable(string str) {
|
|
try {
|
|
byte[] bytes = System.Text.Encoding.UTF8.GetBytes(str);
|
|
byte[] withNull = new byte[bytes.Length + 1];
|
|
Array.Copy(bytes, 0, withNull, 0, bytes.Length);
|
|
withNull[withNull.Length - 1] = 0;
|
|
return withNull;
|
|
} catch {
|
|
byte[] empty = new byte[1];
|
|
empty[0] = 0;
|
|
return empty;
|
|
}
|
|
}
|
|
}
|
|
}
|