1 files changed, 49 insertions, 0 deletions
diff --git a/Jellyfin.Api/Middleware/IpBasedAccessValidationMiddleware.cs b/Jellyfin.Api/Middleware/IpBasedAccessValidationMiddleware.cs
new file mode 100644
index 000000000..f45b6b5c0
--- /dev/null
+++ b/Jellyfin.Api/Middleware/IpBasedAccessValidationMiddleware.cs
@@ -0,0 +1,49 @@
+using System.Net;
+using System.Threading.Tasks;
+using MediaBrowser.Common.Extensions;
+using MediaBrowser.Common.Net;
+using Microsoft.AspNetCore.Http;
+
+namespace Jellyfin.Api.Middleware;
+
+/// <summary>
+/// Validates the IP of requests coming from local networks wrt. remote access.
+/// </summary>
+public class IpBasedAccessValidationMiddleware
+{
+    private readonly RequestDelegate _next;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="IpBasedAccessValidationMiddleware"/> class.
+    /// </summary>
+    /// <param name="next">The next delegate in the pipeline.</param>
+    public IpBasedAccessValidationMiddleware(RequestDelegate next)
+    {
+        _next = next;
+    }
+
+    /// <summary>
+    /// Executes the middleware action.
+    /// </summary>
+    /// <param name="httpContext">The current HTTP context.</param>
+    /// <param name="networkManager">The network manager.</param>
+    /// <returns>The async task.</returns>
+    public async Task Invoke(HttpContext httpContext, INetworkManager networkManager)
+    {
+        if (httpContext.IsLocal())
+        {
+            // Running locally.
+            await _next(httpContext).ConfigureAwait(false);
+            return;
+        }
+
+        var remoteIp = httpContext.Connection.RemoteIpAddress ?? IPAddress.Loopback;
+
+        if (!networkManager.HasRemoteAccess(remoteIp))
+        {
+            return;
+        }
+
+        await _next(httpContext).ConfigureAwait(false);
+    }
+}