From 3b1b3ac9bbd77796a55bcc75d08f78bff5ca78af Mon Sep 17 00:00:00 2001
From: Adam Frisby <adam@gwala.net>
Date: Sat, 23 May 2009 05:44:18 +0000
Subject: [PATCH] * Breaks OpenSim.. err I mean.. adds NAT translation support
 to EnableSimulator EventQueue methods. * NB: This may actually break logins
 on certain regions. Shake well before consuming.

---
 OpenSim/Framework/NetworkUtil.cs              | 40 ++++++++++++++++++-
 .../Hypergrid/HGSceneCommunicationService.cs  |  9 +++++
 .../Scenes/SceneCommunicationService.cs       | 17 ++++++++
 3 files changed, 65 insertions(+), 1 deletion(-)

diff --git a/OpenSim/Framework/NetworkUtil.cs b/OpenSim/Framework/NetworkUtil.cs
index 759c52f8d2..81e6cadfd6 100644
--- a/OpenSim/Framework/NetworkUtil.cs
+++ b/OpenSim/Framework/NetworkUtil.cs
@@ -14,11 +14,49 @@ namespace OpenSim.Framework
     /// This enables standard port forwarding techniques
     /// to work correctly with OpenSim.
     /// </summary>
-    static class NetworkUtil
+    public static class NetworkUtil
     {
         // IPv4Address, Subnet
         static readonly Dictionary<IPAddress,IPAddress> m_subnets = new Dictionary<IPAddress, IPAddress>();
 
+        public static IPAddress GetIPFor(IPAddress user, IPAddress simulator)
+        {
+            // Check if we're accessing localhost.
+            foreach (IPAddress host in Dns.GetHostAddresses(Dns.GetHostName()))
+            {
+                if (host.Equals(user) && host.AddressFamily == AddressFamily.InterNetwork)
+                    return host;
+            }
+
+            // Check for same LAN segment
+            foreach (KeyValuePair<IPAddress, IPAddress> subnet in m_subnets)
+            {
+                byte[] subnetBytes = subnet.Value.GetAddressBytes();
+                byte[] localBytes = subnet.Key.GetAddressBytes();
+                byte[] destBytes = user.GetAddressBytes();
+
+                if (subnetBytes.Length != destBytes.Length || subnetBytes.Length != localBytes.Length)
+                    return null;
+
+                bool valid = true;
+
+                for (int i = 0; i < subnetBytes.Length; i++)
+                {
+                    if ((localBytes[i] & subnetBytes[i]) != (destBytes[i] & subnetBytes[i]))
+                    {
+                        valid = false;
+                        break;
+                    }
+                }
+
+                if (valid)
+                    return subnet.Key;
+            }
+
+            // Otherwise, return outside address
+            return simulator;
+        }
+
         private static IPAddress GetExternalIPFor(IPAddress destination, string defaultHostname)
         {
             // Adds IPv6 Support (Not that any of the major protocols supports it...)
diff --git a/OpenSim/Region/Framework/Scenes/Hypergrid/HGSceneCommunicationService.cs b/OpenSim/Region/Framework/Scenes/Hypergrid/HGSceneCommunicationService.cs
index 542e7d0ea2..7d55cc837f 100644
--- a/OpenSim/Region/Framework/Scenes/Hypergrid/HGSceneCommunicationService.cs
+++ b/OpenSim/Region/Framework/Scenes/Hypergrid/HGSceneCommunicationService.cs
@@ -33,6 +33,7 @@ using System.Threading;
 using log4net;
 using OpenMetaverse;
 using OpenSim.Framework;
+using OpenSim.Framework.Client;
 using OpenSim.Framework.Communications;
 using OpenSim.Framework.Communications.Cache;
 using OpenSim.Framework.Communications.Capabilities;
@@ -211,6 +212,14 @@ namespace OpenSim.Region.Framework.Scenes.Hypergrid
 
                             if (eq != null)
                             {
+                                #region IP Translation for NAT
+                                IClientIPEndpoint ipepClient;
+                                if (avatar.ClientView.TryGet(out ipepClient))
+                                {
+                                    endPoint.Address = NetworkUtil.GetIPFor(ipepClient.EndPoint, endPoint.Address);
+                                }
+                                #endregion
+
                                 eq.EnableSimulator(realHandle, endPoint, avatar.UUID);
 
                                 // ES makes the client send a UseCircuitCode message to the destination, 
diff --git a/OpenSim/Region/Framework/Scenes/SceneCommunicationService.cs b/OpenSim/Region/Framework/Scenes/SceneCommunicationService.cs
index 0699552c49..85a3d96e5d 100644
--- a/OpenSim/Region/Framework/Scenes/SceneCommunicationService.cs
+++ b/OpenSim/Region/Framework/Scenes/SceneCommunicationService.cs
@@ -34,6 +34,7 @@ using OpenMetaverse;
 using OpenMetaverse.StructuredData;
 using log4net;
 using OpenSim.Framework;
+using OpenSim.Framework.Client;
 using OpenSim.Framework.Communications;
 using OpenSim.Framework.Communications.Cache;
 using OpenSim.Framework.Communications.Capabilities;
@@ -306,6 +307,14 @@ namespace OpenSim.Region.Framework.Scenes
                 IEventQueue eq = avatar.Scene.RequestModuleInterface<IEventQueue>();
                 if (eq != null)
                 {
+                    #region IP Translation for NAT
+                    IClientIPEndpoint ipepClient;
+                    if(avatar.ClientView.TryGet(out ipepClient))
+                    {
+                        endPoint.Address = NetworkUtil.GetIPFor(ipepClient.EndPoint, endPoint.Address);
+                    }
+                    #endregion
+
                     eq.EnableSimulator(reg.RegionHandle, endPoint, avatar.UUID);
                     eq.EstablishAgentCommunication(avatar.UUID, endPoint, capsPath);
                     m_log.DebugFormat("[CAPS]: Sending new CAPS seed url {0} to client {1} in region {2}", 
@@ -812,6 +821,14 @@ namespace OpenSim.Region.Framework.Scenes
 
                             if (eq != null)
                             {
+                                #region IP Translation for NAT
+                                IClientIPEndpoint ipepClient;
+                                if (avatar.ClientView.TryGet(out ipepClient))
+                                {
+                                    endPoint.Address = NetworkUtil.GetIPFor(ipepClient.EndPoint, endPoint.Address);
+                                }
+                                #endregion
+
                                 eq.EnableSimulator(reg.RegionHandle, endPoint, avatar.UUID);
 
                                 // ES makes the client send a UseCircuitCode message to the destination,