From 6f0d5a0583593f4ffe82f6029b609b1bbf622f83 Mon Sep 17 00:00:00 2001
From: Robin Dadswell <19610103+RobinDadswell@users.noreply.github.com>
Date: Sun, 30 May 2021 14:21:06 +0100
Subject: [PATCH] Fixed: Real IP Logging when IPv4 mapped as IPv6 (#6362)

---
 src/Radarr.Http/Extensions/RequestExtensions.cs | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/src/Radarr.Http/Extensions/RequestExtensions.cs b/src/Radarr.Http/Extensions/RequestExtensions.cs
index df2179d9c..971bef901 100644
--- a/src/Radarr.Http/Extensions/RequestExtensions.cs
+++ b/src/Radarr.Http/Extensions/RequestExtensions.cs
@@ -95,10 +95,23 @@ namespace Radarr.Http.Extensions
             }
 
             var remoteAddress = context.Request.UserHostAddress;
-            IPAddress remoteIP;
+
+            IPAddress.TryParse(remoteAddress, out IPAddress remoteIP);
+
+            if (remoteIP == null)
+            {
+                return remoteAddress;
+            }
+
+            if (remoteIP.IsIPv4MappedToIPv6)
+            {
+                remoteIP = remoteIP.MapToIPv4();
+            }
+
+            remoteAddress = remoteIP.ToString();
 
             // Only check if forwarded by a local network reverse proxy
-            if (IPAddress.TryParse(remoteAddress, out remoteIP) && remoteIP.IsLocalAddress())
+            if (remoteIP.IsLocalAddress())
             {
                 var realIPHeader = context.Request.Headers["X-Real-IP"];
                 if (realIPHeader.Any())