1 files changed, 21 insertions, 1 deletions
diff --git a/MediaBrowser.Common/Net/NetworkUtils.cs b/MediaBrowser.Common/Net/NetworkUtils.cs
index e482089f0..a498d6271 100644
--- a/MediaBrowser.Common/Net/NetworkUtils.cs
+++ b/MediaBrowser.Common/Net/NetworkUtils.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
+using System.Globalization;
 using System.Net;
 using System.Net.Sockets;
 using System.Text.RegularExpressions;
@@ -102,7 +103,7 @@ public static partial class NetworkUtils
         Span<byte> bytes = stackalloc byte[mask.AddressFamily == AddressFamily.InterNetwork ? NetworkConstants.IPv4MaskBytes : NetworkConstants.IPv6MaskBytes];
         if (!mask.TryWriteBytes(bytes, out var bytesWritten))
         {
-            Console.WriteLine("Unable to write address bytes, only ${bytesWritten} bytes written.");
+            Console.WriteLine("Unable to write address bytes, only {0} bytes written.", bytesWritten.ToString(CultureInfo.InvariantCulture));
         }
 
         var zeroed = false;
@@ -325,4 +326,23 @@ public static partial class NetworkUtils
 
         return new IPAddress(BitConverter.GetBytes(broadCastIPAddress));
     }
+
+    /// <summary>
+    /// Check if a subnet contains an address. This method also handles IPv4 mapped to IPv6 addresses.
+    /// </summary>
+    /// <param name="network">The <see cref="IPNetwork"/>.</param>
+    /// <param name="address">The <see cref="IPAddress"/>.</param>
+    /// <returns>Whether the supplied IP is in the supplied network.</returns>
+    public static bool SubnetContainsAddress(IPNetwork network, IPAddress address)
+    {
+        ArgumentNullException.ThrowIfNull(address);
+        ArgumentNullException.ThrowIfNull(network);
+
+        if (address.IsIPv4MappedToIPv6)
+        {
+            address = address.MapToIPv4();
+        }
+
+        return network.Contains(address);
+    }
 }