Added IConnectionSocketFeature for exposing underlying Socket!

src/Servers/Connections.Abstractions/src/Features/IConnectionSocketFeature.cs

@@ -0,0 +1,18 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Net.Sockets;
+
+namespace Microsoft.AspNetCore.Connections.Features
+{
+    /// <summary>
+    /// Provides access to the connection's underlying <see cref="Socket"/> if any.
+    /// </summary>
+    public interface IConnectionSocketFeature
+    {
+        /// <summary>
+        /// Gets the underlying <see cref="Socket"/>.
+        /// </summary>
+        Socket? Socket { get; }
+    }
+}

src/Servers/Connections.Abstractions/src/PublicAPI.Unshipped.txt

@@ -1,5 +1,7 @@
 #nullable enable
 *REMOVED*Microsoft.AspNetCore.Connections.IConnectionListener.AcceptAsync(System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) -> System.Threading.Tasks.ValueTask<Microsoft.AspNetCore.Connections.ConnectionContext!>
+Microsoft.AspNetCore.Connections.Features.IConnectionSocketFeature
+Microsoft.AspNetCore.Connections.Features.IConnectionSocketFeature.Socket.get -> System.Net.Sockets.Socket?
 Microsoft.AspNetCore.Connections.IConnectionListener.AcceptAsync(System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) -> System.Threading.Tasks.ValueTask<Microsoft.AspNetCore.Connections.ConnectionContext?>
 Microsoft.AspNetCore.Connections.Experimental.IMultiplexedConnectionBuilder
 Microsoft.AspNetCore.Connections.Experimental.IMultiplexedConnectionBuilder.ApplicationServices.get -> System.IServiceProvider!

src/Servers/Kestrel/Transport.Sockets/src/Internal/SocketConnection.cs

@@ -51,6 +51,7 @@ internal SocketConnection(Socket socket,
             MemoryPool = memoryPool;
             _trace = trace;
             _waitForData = waitForData;
+            Socket = socket;
             _socketSenderPool = socketSenderPool;
 
             LocalEndPoint = _socket.LocalEndPoint;

src/Servers/Kestrel/shared/TransportConnection.FeatureCollection.cs

@@ -4,6 +4,7 @@
 using System.Buffers;
 using System.Collections.Generic;
 using System.IO.Pipelines;
+using System.Net.Sockets;
 using System.Threading;
 using Microsoft.AspNetCore.Connections.Features;
 
@@ -38,6 +39,8 @@ CancellationToken IConnectionLifetimeFeature.ConnectionClosed
             set => ConnectionClosed = value;
         }
 
+        Socket? IConnectionSocketFeature.Socket => Socket;
+
         void IConnectionLifetimeFeature.Abort() => Abort(new ConnectionAbortedException("The connection was aborted by the application via IConnectionLifetimeFeature.Abort()."));
     }
 }

src/Servers/Kestrel/shared/TransportConnection.Generated.cs

@@ -18,14 +18,16 @@ internal partial class TransportConnection : IFeatureCollection,
                                                  IConnectionTransportFeature,
                                                  IConnectionItemsFeature,
                                                  IMemoryPoolFeature,
-                                                 IConnectionLifetimeFeature
+                                                 IConnectionLifetimeFeature,
+                                                 IConnectionSocketFeature
     {
         // Implemented features
         internal protected IConnectionIdFeature? _currentIConnectionIdFeature;
         internal protected IConnectionTransportFeature? _currentIConnectionTransportFeature;
         internal protected IConnectionItemsFeature? _currentIConnectionItemsFeature;
         internal protected IMemoryPoolFeature? _currentIMemoryPoolFeature;
         internal protected IConnectionLifetimeFeature? _currentIConnectionLifetimeFeature;
+        internal protected IConnectionSocketFeature? _currentIConnectionSocketFeature;
 
         private int _featureRevision;
 
@@ -38,6 +40,7 @@ private void FastReset()
             _currentIConnectionItemsFeature = this;
             _currentIMemoryPoolFeature = this;
             _currentIConnectionLifetimeFeature = this;
+            _currentIConnectionSocketFeature = this;
 
         }
 
@@ -130,6 +133,10 @@ private void ExtraFeatureSet(Type key, object? value)
                 {
                     feature = _currentIConnectionLifetimeFeature;
                 }
+                else if (key == typeof(IConnectionSocketFeature))
+                {
+                    feature = _currentIConnectionSocketFeature;
+                }
                 else if (MaybeExtra != null)
                 {
                     feature = ExtraFeatureGet(key);
@@ -162,6 +169,10 @@ private void ExtraFeatureSet(Type key, object? value)
                 {
                     _currentIConnectionLifetimeFeature = (IConnectionLifetimeFeature?)value;
                 }
+                else if (key == typeof(IConnectionSocketFeature))
+                {
+                    _currentIConnectionSocketFeature = (IConnectionSocketFeature?)value;
+                }
                 else
                 {
                     ExtraFeatureSet(key, value);
@@ -196,6 +207,10 @@ private void ExtraFeatureSet(Type key, object? value)
             {
                 feature = Unsafe.As<IConnectionLifetimeFeature?, TFeature?>(ref _currentIConnectionLifetimeFeature);
             }
+            else if (typeof(TFeature) == typeof(IConnectionSocketFeature))
+            {
+                feature = Unsafe.As<IConnectionSocketFeature?, TFeature?>(ref _currentIConnectionSocketFeature);
+            }
             else if (MaybeExtra != null)
             {
                 feature = (TFeature?)(ExtraFeatureGet(typeof(TFeature)));
@@ -231,6 +246,10 @@ private void ExtraFeatureSet(Type key, object? value)
             {
                 _currentIConnectionLifetimeFeature = Unsafe.As<TFeature?, IConnectionLifetimeFeature?>(ref feature);
             }
+            else if (typeof(TFeature) == typeof(IConnectionSocketFeature))
+            {
+                _currentIConnectionSocketFeature = Unsafe.As<TFeature?, IConnectionSocketFeature?>(ref feature);
+            }
             else
             {
                 ExtraFeatureSet(typeof(TFeature), feature);
@@ -259,6 +278,10 @@ private IEnumerable<KeyValuePair<Type, object>> FastEnumerable()
             {
                 yield return new KeyValuePair<Type, object>(typeof(IConnectionLifetimeFeature), _currentIConnectionLifetimeFeature);
             }
+            if (_currentIConnectionSocketFeature != null)
+            {
+                yield return new KeyValuePair<Type, object>(typeof(IConnectionSocketFeature), _currentIConnectionSocketFeature);
+            }
 
             if (MaybeExtra != null)
             {

src/Servers/Kestrel/shared/TransportConnection.cs

@@ -1,12 +1,12 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using System;
 using System.Buffers;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO.Pipelines;
 using System.Net;
+using System.Net.Sockets;
 using System.Threading;
 using Microsoft.AspNetCore.Http.Features;
 
@@ -65,6 +65,8 @@ public override string ConnectionId
             }
         }
 
+        public Socket? Socket { get; protected set; }
+
         public override CancellationToken ConnectionClosed { get; set; }
 
         // DO NOT remove this override to ConnectionContext.Abort. Doing so would cause

src/Servers/Kestrel/tools/CodeGenerator/TransportConnectionFeatureCollection.cs

@@ -17,7 +17,8 @@ public static string GenerateFile()
                 "IConnectionTransportFeature",
                 "IConnectionItemsFeature",
                 "IMemoryPoolFeature",
-                "IConnectionLifetimeFeature"
+                "IConnectionLifetimeFeature",
+                "IConnectionSocketFeature"
             };
 
             var usings = $@"