Revert "Change ApplicationProtocol to ReadOnlyMemory<byte> #2182"

This reverts commit 2d3a01d48d.

samples/Http2SampleApp/Http2SampleApp.csproj

@@ -15,9 +15,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <Content Include="testCert.pfx">
+    <Content Include="../../test/shared/TestCertificates/testCert.pfx" CopyToOutputDirectory="PreserveNewest" />
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </Content>
   </ItemGroup>
 
 </Project>

src/Kestrel.Core/Features/ITlsApplicationProtocolFeature.cs

@@ -1,12 +1,11 @@
 // 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;
-
 namespace Microsoft.AspNetCore.Server.Kestrel.Core.Features
 {
+    // TODO: this should be merged with ITlsConnectionFeature
     public interface ITlsApplicationProtocolFeature
     {
-        ReadOnlyMemory<byte> ApplicationProtocol { get; }
+        string ApplicationProtocol { get; }
     }
 }

src/Kestrel.Core/Internal/HttpConnection.cs

@@ -23,8 +23,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
 {
     public class HttpConnection : ITimeoutControl, IConnectionTimeoutFeature, IRequestProcessor
     {
-        private static readonly ReadOnlyMemory<byte> Http2Id = new ReadOnlyMemory<byte>(new[] { (byte)'h', (byte)'2' });
-
         private readonly HttpConnectionContext _context;
         private readonly TaskCompletionSource<object> _socketClosedTcs = new TaskCompletionSource<object>(TaskCreationOptions.RunContinuationsAsynchronously);
 
@@ -305,8 +303,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
         private HttpProtocols SelectProtocol()
         {
             var hasTls = _context.ConnectionFeatures.Get<ITlsConnectionFeature>() != null;
-            var applicationProtocol = _context.ConnectionFeatures.Get<ITlsApplicationProtocolFeature>()?.ApplicationProtocol
+            var applicationProtocol = _context.ConnectionFeatures.Get<ITlsApplicationProtocolFeature>()?.ApplicationProtocol;
-                ?? new ReadOnlyMemory<byte>();
             var http1Enabled = (_context.Protocols & HttpProtocols.Http1) == HttpProtocols.Http1;
             var http2Enabled = (_context.Protocols & HttpProtocols.Http2) == HttpProtocols.Http2;
 
@@ -322,7 +319,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
                 error = CoreStrings.EndPointRequiresTlsForHttp1AndHttp2;
             }
 
-            if (!http1Enabled && http2Enabled && hasTls && !Http2Id.SequenceEqual(applicationProtocol))
+            if (!http1Enabled && http2Enabled && hasTls && applicationProtocol != "h2")
             {
                 error = CoreStrings.EndPointHttp2NotNegotiated;
             }
@@ -333,7 +330,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
                 return HttpProtocols.None;
             }
 
-            return http2Enabled && (!hasTls || Http2Id.SequenceEqual(applicationProtocol)) ? HttpProtocols.Http2 : HttpProtocols.Http1;
+            return http2Enabled && (!hasTls || applicationProtocol == "h2") ? HttpProtocols.Http2 : HttpProtocols.Http1;
         }
 
         public void Tick(DateTimeOffset now)

src/Kestrel.Core/Internal/HttpsConnectionAdapter.cs

@@ -160,7 +160,20 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Https.Internal
             }
 
 #if NETCOREAPP2_1
-            feature.ApplicationProtocol = sslStream.NegotiatedApplicationProtocol.Protocol;
+            // Don't allocate in the common case, see https://github.com/dotnet/corefx/issues/25432
+            if (sslStream.NegotiatedApplicationProtocol == SslApplicationProtocol.Http11)
+            {
+                feature.ApplicationProtocol = "http/1.1";
+            }
+            else if (sslStream.NegotiatedApplicationProtocol == SslApplicationProtocol.Http2)
+            {
+                feature.ApplicationProtocol = "h2";
+            }
+            else
+            {
+                feature.ApplicationProtocol = sslStream.NegotiatedApplicationProtocol.ToString();
+            }
+
             context.Features.Set<ITlsApplicationProtocolFeature>(feature);
 #endif
             feature.ClientCertificate = ConvertToX509Certificate2(sslStream.RemoteCertificate);

src/Kestrel.Core/Internal/TlsConnectionFeature.cs

@@ -14,7 +14,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Https.Internal
     {
         public X509Certificate2 ClientCertificate { get; set; }
 
-        public ReadOnlyMemory<byte> ApplicationProtocol { get; set; }
+        public string ApplicationProtocol { get; set; }
 
         public Task<X509Certificate2> GetClientCertificateAsync(CancellationToken cancellationToken)
         {

src/Kestrel.Core/Kestrel.Core.csproj

@@ -4,7 +4,7 @@
     <AssemblyName>Microsoft.AspNetCore.Server.Kestrel.Core</AssemblyName>
     <RootNamespace>Microsoft.AspNetCore.Server.Kestrel.Core</RootNamespace>
     <Description>Core components of ASP.NET Core Kestrel cross-platform web server.</Description>
-    <TargetFrameworks>netstandard2.0;netcoreapp2.1</TargetFrameworks>
+    <TargetFramework>netstandard2.0</TargetFramework>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
     <PackageTags>aspnetcore;kestrel</PackageTags>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>