1 files changed, 85 insertions, 2 deletions
diff --git a/MediaBrowser.Common.Implementations/Networking/BaseNetworkManager.cs b/MediaBrowser.Common.Implementations/Networking/BaseNetworkManager.cs
index e15c32518..8159be634 100644
--- a/MediaBrowser.Common.Implementations/Networking/BaseNetworkManager.cs
+++ b/MediaBrowser.Common.Implementations/Networking/BaseNetworkManager.cs
@@ -1,4 +1,5 @@
-using System;
+using MediaBrowser.Model.Logging;
+using System;
 using System.Collections.Generic;
 using System.Globalization;
 using System.Linq;
@@ -10,6 +11,13 @@ namespace MediaBrowser.Common.Implementations.Networking
 {
     public abstract class BaseNetworkManager
     {
+        protected ILogger Logger { get; private set; }
+
+        protected BaseNetworkManager(ILogger logger)
+        {
+            Logger = logger;
+        }
+
         /// <summary>
         /// Gets the machine's local ip address
         /// </summary>
@@ -26,6 +34,81 @@ namespace MediaBrowser.Common.Implementations.Networking
             return GetLocalIpAddressesFallback();
         }
 
+        public bool IsInLocalNetwork(string endpoint)
+        {
+            return IsInLocalNetworkInternal(endpoint, true);
+        }
+
+        public bool IsInLocalNetworkInternal(string endpoint, bool resolveHost)
+        {
+            if (string.IsNullOrWhiteSpace(endpoint))
+            {
+                throw new ArgumentNullException("endpoint");
+            }
+
+            const int lengthMatch = 4;
+
+            if (endpoint.Length >= lengthMatch)
+            {
+                var prefix = endpoint.Substring(0, lengthMatch);
+
+                if (GetLocalIpAddresses()
+                    .Any(i => i.StartsWith(prefix, StringComparison.OrdinalIgnoreCase)))
+                {
+                    return true;
+                }
+            }
+
+            // Private address space:
+            // http://en.wikipedia.org/wiki/Private_network
+
+            var isPrivate =
+
+                // If url was requested with computer name, we may see this
+                endpoint.IndexOf("::", StringComparison.OrdinalIgnoreCase) != -1 ||
+
+                endpoint.StartsWith("10.", StringComparison.OrdinalIgnoreCase) ||
+                endpoint.StartsWith("192.", StringComparison.OrdinalIgnoreCase) ||
+                endpoint.StartsWith("172.", StringComparison.OrdinalIgnoreCase) ||
+                endpoint.StartsWith("169.", StringComparison.OrdinalIgnoreCase);
+
+            if (isPrivate)
+            {
+                return true;
+            }
+
+            IPAddress address;
+            if (resolveHost && !IPAddress.TryParse(endpoint, out address))
+            {
+                var host = new Uri(endpoint).DnsSafeHost;
+
+                Logger.Debug("Resolving host {0}", host);
+
+                try
+                {
+                    address = GetIpAddresses(host).FirstOrDefault();
+
+                    if (address != null)
+                    {
+                        Logger.Debug("{0} resolved to {1}", host, address);
+
+                        return IsInLocalNetworkInternal(address.ToString(), false);
+                    }
+                }
+                catch (Exception ex)
+                {
+                    Logger.ErrorException("Error resovling hostname {0}", ex, host);
+                }
+            }
+
+            return false;
+        }
+        
+        public IEnumerable<IPAddress> GetIpAddresses(string hostName)
+        {
+            return Dns.GetHostAddresses(hostName);
+        }
+
         private IEnumerable<IPAddress> GetIPsDefault()
         {
             foreach (var adapter in NetworkInterface.GetAllNetworkInterfaces())
@@ -63,7 +146,7 @@ namespace MediaBrowser.Common.Implementations.Networking
                 .Select(i => i.ToString())
                 .Reverse();
         }
-        
+
         /// <summary>
         /// Gets a random port number that is currently available
         /// </summary>