Respond to PR feedback.

Author: Lakshmi Priya Sekar

src/Common/src/Interop/Unix/System.Security.Cryptography.Native/Interop.OpenSslVersion.cs

@@ -0,0 +1,36 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Runtime.InteropServices;
+
+internal static partial class Interop
+{
+    internal static partial class OpenSsl
+    {
+        private static Version s_opensslVersion;
+
+        [DllImport(Libraries.CryptoNative, EntryPoint = "CryptoNative_SSLEayVersion")]
+        private static extern string OpenSslVersionDescription();
+
+        internal static Version OpenSslVersion
+        {
+            get
+            {
+                if (s_opensslVersion == null)
+                {
+                    const string OpenSSL = "OpenSSL ";
+
+                    // Skip OpenSSL part, and get the version string of format x.y.z
+                    if (!Version.TryParse(OpenSslVersionDescription().AsReadOnlySpan().Slice(OpenSSL.Length, 5), out s_opensslVersion))
+                    {
+                        s_opensslVersion = new Version(0, 0, 0);
+                    }
+                }
+
+                return s_opensslVersion;
+            }
+        }
+    }
+}

src/CoreFx.Private.TestUtilities/ref/CoreFx.Private.TestUtilities.cs

@@ -77,6 +77,7 @@ public static partial class PlatformDetection
         public static bool IsNotRedHatFamily6 { get { throw null; } }
         public static bool IsUap { get { throw null; } }
         public static Version ICUVersion { get { return null; } }
+        public static Version OpenSslVersion { get { return null; } }
         public static bool IsUbuntu { get { throw null; } }
         public static bool IsUbuntu1404 { get { throw null; } }
         public static bool IsUbuntu1604 { get { throw null; } }

src/CoreFx.Private.TestUtilities/src/CoreFx.Private.TestUtilities.csproj

@@ -42,6 +42,7 @@
     <Compile Include="System\TheoryExtensions.cs" />
   </ItemGroup>
   <ItemGroup>
+    <Reference Include="System.Memory" />
     <Reference Include="Microsoft.Win32.Registry" />
     <Reference Include="System.Runtime" />
     <Reference Include="System.IO.FileSystem" />
@@ -93,6 +94,9 @@
     <Compile Include="System\AdminHelpers.Windows.cs" />
   </ItemGroup>
   <ItemGroup Condition="'$(TargetsUnix)' == 'true'">
+    <Compile Include="$(CommonPath)\Interop\Unix\System.Security.Cryptography.Native\Interop.OpenSslVersion.cs">
+      <Link>Common\Interop\Unix\System.Security.Cryptography.Native\Interop.OpenSslVersion.cs</Link>
+    </Compile>
     <Compile Include="System\AdminHelpers.Unix.cs" />
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetEUid.cs">
       <Link>Common\Interop\Unix\Interop.GetEUid.cs</Link>
@@ -115,4 +119,4 @@
     <EmbeddedResource Include="Resources\$(AssemblyName).rd.xml" />
   </ItemGroup>
   <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory), dir.targets))\dir.targets" />
-</Project>
+</Project>

src/CoreFx.Private.TestUtilities/src/System/PlatformDetection.Unix.cs

@@ -52,6 +52,8 @@ public static partial class PlatformDetection
 
         public static Version OSXVersion { get; } = ToVersion(Microsoft.DotNet.PlatformAbstractions.RuntimeEnvironment.OperatingSystemVersion);
 
+        public static Version OpenSslVersion => RuntimeInformation.IsOSPlatform(OSPlatform.Linux) ? Interop.OpenSsl.OpenSslVersion : throw new PlatformNotSupportedException();
+
         public static string GetDistroVersionString()
         {
             if (RuntimeInformation.IsOSPlatform(OSPlatform.OSX))

src/CoreFx.Private.TestUtilities/src/System/PlatformDetection.Windows.cs

@@ -15,6 +15,7 @@ namespace System
     public static partial class PlatformDetection
     {
         public static Version OSXVersion => throw new PlatformNotSupportedException();
+        public static Version OpenSslVersion => throw new PlatformNotSupportedException();
         public static bool IsSuperUser => throw new PlatformNotSupportedException();
         public static bool IsCentos6 => false;
         public static bool IsOpenSUSE => false;

src/System.Net.Security/tests/FunctionalTests/SslStreamAlpnTests.cs

@@ -20,67 +20,14 @@ namespace System.Net.Security.Tests
 {
     using Configuration = System.Net.Test.Common.Configuration;
 
-#if TargetsLinux
-    internal static class OpenSslVersionProvider
-    {
-        private static string s_opensslVersion;
-
-        [DllImport("System.Security.Cryptography.Native.OpenSsl", EntryPoint = "CryptoNative_SSLEayVersion")]
-        private static extern string OpenSslVersionDescription();
-
-        private static string OpenSslVersionNumber
-        {
-            get
-            {
-                if (s_opensslVersion == null)
-                {
-                    const string OpenSSL = "OpenSSL ";
-
-                    // Skip OpenSSL part, and get the version string of format x.y.z
-                    s_opensslVersion  = OpenSslVersionDescription().Substring(OpenSSL.Length, 5);
-                }
-
-                return s_opensslVersion;
-            }
-        }
-
-        internal static int MajorVersion
-        {
-            get
-            {
-                int digit = OpenSslVersionNumber[0] - '0';
-                return (digit >= 0 && digit <= 9) ? digit : -1;
-            }
-        }
-
-        internal static int MinorVersion
-        {
-            get
-            {
-                int digit = OpenSslVersionNumber[2] - '0';
-                return (digit >= 0 && digit <= 9) ? digit : -1;
-            }
-        }
-
-        internal static int BuildVersion
-        {
-            get
-            {
-                int digit = OpenSslVersionNumber[4] - '0';
-                return (digit >= 0 && digit <= 9) ? digit : -1;
-            }
-        }
-    }
-#endif
-
     public class SslStreamAlpnTests
     {
-        private static bool BackendSupportsAlpn =>
-#if TargetsLinux
-            OpenSslVersionProvider.MajorVersion >= 1 && (OpenSslVersionProvider.MinorVersion >= 1 || OpenSslVersionProvider.BuildVersion >= 2);
-#else
-            PlatformDetection.IsWindows && !PlatformDetection.IsWindows7;
-#endif
+        // Windows - Schannel supports alpn from win8 and higher.
+        // Linux - OpenSsl supports alpn from openssl 1.0.2 and higher.
+        // OSX - SecureTransport doesn't expose alpn APIs.
+        private static bool BackendSupportsAlpn => (PlatformDetection.IsWindows && !PlatformDetection.IsWindows7) ||
+            (RuntimeInformation.IsOSPlatform(OSPlatform.Linux) &&
+            (PlatformDetection.OpenSslVersion.Major >= 1 && (PlatformDetection.OpenSslVersion.Minor >= 1 || PlatformDetection.OpenSslVersion.Build >= 2)));
 
         private async Task DoHandshakeWithOptions(SslStream clientSslStream, SslStream serverSslStream, SslClientAuthenticationOptions clientOptions, SslServerAuthenticationOptions serverOptions)
         {

src/System.Net.Security/tests/FunctionalTests/System.Net.Security.Tests.csproj

@@ -7,9 +7,6 @@
   <PropertyGroup Condition=" '$(TargetsUnix)' == 'true' ">
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
   </PropertyGroup>
-  <PropertyGroup Condition=" '$(TargetsLinux)' == 'true'">
-    <DefineConstants>TargetsLinux</DefineConstants>
-  </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='netstandard-Unix-Debug|AnyCPU'" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='netstandard-Unix-Release|AnyCPU'" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='netstandard-Windows_NT-Debug|AnyCPU'" />