diff --git a/src/csharp/Grpc.Auth/.gitignore b/src/csharp/Grpc.Auth/.gitignore
new file mode 100644
index 0000000000000000000000000000000000000000..c2dd6641675ac03d8a7e5d6af6f03637ef4cd137
--- /dev/null
+++ b/src/csharp/Grpc.Auth/.gitignore
@@ -0,0 +1,3 @@
+bin
+obj
+*.nupkg
diff --git a/src/csharp/Grpc.Auth/GoogleCredential.cs b/src/csharp/Grpc.Auth/GoogleCredential.cs
new file mode 100644
index 0000000000000000000000000000000000000000..d66952a9017d53e62101ff53687cb350df5af2dc
--- /dev/null
+++ b/src/csharp/Grpc.Auth/GoogleCredential.cs
@@ -0,0 +1,115 @@
+#region Copyright notice and license
+
+// Copyright 2015, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.IO;
+using System.Threading.Tasks;
+using Grpc.Core;
+using Grpc.Core.Utils;
+
+using Google.Apis.Auth.OAuth2;
+using System.Security.Cryptography.X509Certificates;
+
+namespace Grpc.Auth
+{
+ // TODO(jtattermusch): Remove this class once possible.
+ /// <summary>
+ /// A temporary placeholder for Google credential from
+ /// Google Auth library for .NET. It emulates the usage pattern
+ /// for Usable auth.
+ /// </summary>
+ public class GoogleCredential
+ {
+ private const string GoogleApplicationCredentialsEnvName = "GOOGLE_APPLICATION_CREDENTIALS";
+
+ private ServiceCredential credential;
+
+ private GoogleCredential(ServiceCredential credential)
+ {
+ this.credential = credential;
+ }
+
+ public static GoogleCredential GetApplicationDefault()
+ {
+ return new GoogleCredential(null);
+ }
+
+ public bool IsCreateScopedRequired
+ {
+ get
+ {
+ return true;
+ }
+ }
+
+ public GoogleCredential CreateScoped(IEnumerable<string> scopes)
+ {
+
+ // TODO: also support compute credential.
+
+ //var credsPath = Environment.GetEnvironmentVariable("GOOGLE_APPLICATION_CREDENTIALS");
+ //var credsPath = "/usr/local/google/home/jtattermusch/certs/service_account/stubbyCloudTestingTest-7dd63462c60c.json";
+
+ //JObject o1 = JObject.Parse(File.ReadAllText(credsPath));
+ //string privateKey = o1.GetValue("private_key").Value<string>();
+ //Console.WriteLine(privateKey);
+
+ //var certificate = new X509Certificate2(System.Text.Encoding.UTF8.GetBytes(privateKey), "notasecret", X509KeyStorageFlags.Exportable);
+
+ // TODO: support JSON key file.
+
+ // TODO: get file location from GoogleApplicationCredential env var
+ var certificate = new X509Certificate2("/usr/local/google/home/jtattermusch/certs/stubbyCloudTestingTest-090796e783f3.p12", "notasecret", X509KeyStorageFlags.Exportable);
+
+ // TODO: auth user will be read from the JSON key
+ string authUser = "155450119199-3psnrh1sdr3d8cpj1v46naggf81mhdnk@developer.gserviceaccount.com";
+
+ var serviceCredential = new ServiceAccountCredential(
+ new ServiceAccountCredential.Initializer(authUser)
+ {
+ Scopes = scopes
+ }.FromCertificate(certificate));
+ return new GoogleCredential(serviceCredential);
+ }
+
+ internal ServiceCredential InternalCredential
+ {
+ get
+ {
+ return credential;
+ }
+ }
+ }
+}
diff --git a/src/csharp/Grpc.Auth/Grpc.Auth.csproj b/src/csharp/Grpc.Auth/Grpc.Auth.csproj
new file mode 100644
index 0000000000000000000000000000000000000000..dbbee780a8b6fd1c6fbe0a4ea6d1e11ca8210997
--- /dev/null
+++ b/src/csharp/Grpc.Auth/Grpc.Auth.csproj
@@ -0,0 +1,47 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+ <PropertyGroup>
+ <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+ <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
+ <ProductVersion>10.0.0</ProductVersion>
+ <SchemaVersion>2.0</SchemaVersion>
+ <ProjectGuid>{AE21D0EE-9A2C-4C15-AB7F-5224EED5B0EA}</ProjectGuid>
+ <OutputType>Library</OutputType>
+ <RootNamespace>Grpc.Auth</RootNamespace>
+ <AssemblyName>Grpc.Auth</AssemblyName>
+ <TargetFrameworkVersion>v4.5</TargetFrameworkVersion>
+ </PropertyGroup>
+ <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
+ <DebugSymbols>true</DebugSymbols>
+ <DebugType>full</DebugType>
+ <Optimize>false</Optimize>
+ <OutputPath>bin\Debug</OutputPath>
+ <DefineConstants>DEBUG;</DefineConstants>
+ <ErrorReport>prompt</ErrorReport>
+ <WarningLevel>4</WarningLevel>
+ <ConsolePause>false</ConsolePause>
+ </PropertyGroup>
+ <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
+ <DebugType>full</DebugType>
+ <Optimize>true</Optimize>
+ <OutputPath>bin\Release</OutputPath>
+ <ErrorReport>prompt</ErrorReport>
+ <WarningLevel>4</WarningLevel>
+ <ConsolePause>false</ConsolePause>
+ </PropertyGroup>
+ <ItemGroup>
+ <Reference Include="System" />
+ </ItemGroup>
+ <ItemGroup>
+ <Compile Include="Properties\AssemblyInfo.cs" />
+ <Compile Include="GoogleCredential.cs" />
+ <Compile Include="OAuth2InterceptorFactory.cs" />
+ </ItemGroup>
+ <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
+ <ItemGroup>
+ <ProjectReference Include="..\Grpc.Core\Grpc.Core.csproj">
+ <Project>{CCC4440E-49F7-4790-B0AF-FEABB0837AE7}</Project>
+ <Name>Grpc.Core</Name>
+ </ProjectReference>
+ </ItemGroup>
+</Project>
\ No newline at end of file
diff --git a/src/csharp/Grpc.Auth/OAuth2InterceptorFactory.cs b/src/csharp/Grpc.Auth/OAuth2InterceptorFactory.cs
new file mode 100644
index 0000000000000000000000000000000000000000..ae9d70deb8a7be4714ce51934a170287387f7926
--- /dev/null
+++ b/src/csharp/Grpc.Auth/OAuth2InterceptorFactory.cs
@@ -0,0 +1,66 @@
+#region Copyright notice and license
+
+// Copyright 2015, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.Diagnostics;
+using System.IO;
+using System.Text.RegularExpressions;
+using System.Threading;
+using System.Threading.Tasks;
+using Google.ProtocolBuffers;
+using grpc.testing;
+using Grpc.Core;
+using Grpc.Core.Utils;
+using NUnit.Framework;
+
+using Google.Apis.Auth.OAuth2;
+using System.Security.Cryptography.X509Certificates;
+
+namespace Grpc.Auth
+{
+ public static class OAuth2InterceptorFactory
+ {
+ public static HeaderInterceptorDelegate Create(GoogleCredential googleCredential)
+ {
+ ServiceCredential credential = googleCredential.InternalCredential;
+ credential.RequestAccessTokenAsync(CancellationToken.None).Wait();
+ string accessToken = credential.Token.AccessToken;
+
+ // TODO: token refresh logic!!
+ return new HeaderInterceptorDelegate((b)=> { b.Add(new Metadata.MetadataEntry("Authorization", "Bearer " + accessToken)); });
+
+ }
+ }
+}
diff --git a/src/csharp/Grpc.Auth/Properties/AssemblyInfo.cs b/src/csharp/Grpc.Auth/Properties/AssemblyInfo.cs
new file mode 100644
index 0000000000000000000000000000000000000000..66b18d0ccf0dea0d17f903b47430ac657efcffec
--- /dev/null
+++ b/src/csharp/Grpc.Auth/Properties/AssemblyInfo.cs
@@ -0,0 +1,14 @@
+using System.Reflection;
+using System.Runtime.CompilerServices;
+
+[assembly: AssemblyTitle("Grpc.Auth")]
+[assembly: AssemblyDescription("")]
+[assembly: AssemblyConfiguration("")]
+[assembly: AssemblyCompany("")]
+[assembly: AssemblyProduct("")]
+[assembly: AssemblyCopyright("Google Inc. All rights reserved.")]
+[assembly: AssemblyTrademark("")]
+[assembly: AssemblyCulture("")]
+[assembly: AssemblyVersion("0.2.*")]
+
+[assembly: InternalsVisibleTo("Grpc.Auth.Tests")]
\ No newline at end of file
diff --git a/src/csharp/Grpc.sln b/src/csharp/Grpc.sln
index 2f8c2e171902df02599f5d95335c1d401657907c..e2a374e362a4afc38db8de6a7bff84ce4d469243 100644
--- a/src/csharp/Grpc.sln
+++ b/src/csharp/Grpc.sln
@@ -19,6 +19,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Grpc.IntegrationTesting.Ser
EndProject
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Grpc.Examples.MathServer", "Grpc.Examples.MathServer\Grpc.Examples.MathServer.csproj", "{BF62FE08-373A-43D6-9D73-41CAA38B7011}"
EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Grpc.Auth", "Grpc.Auth\Grpc.Auth.csproj", "{AE21D0EE-9A2C-4C15-AB7F-5224EED5B0EA}"
+EndProject
Global
GlobalSection(SolutionConfigurationPlatforms) = preSolution
Debug|x86 = Debug|x86
@@ -49,6 +51,10 @@ Global
{A654F3B8-E859-4E6A-B30D-227527DBEF0D}.Debug|x86.Build.0 = Debug|x86
{A654F3B8-E859-4E6A-B30D-227527DBEF0D}.Release|x86.ActiveCfg = Release|x86
{A654F3B8-E859-4E6A-B30D-227527DBEF0D}.Release|x86.Build.0 = Release|x86
+ {AE21D0EE-9A2C-4C15-AB7F-5224EED5B0EA}.Debug|x86.ActiveCfg = Debug|Any CPU
+ {AE21D0EE-9A2C-4C15-AB7F-5224EED5B0EA}.Debug|x86.Build.0 = Debug|Any CPU
+ {AE21D0EE-9A2C-4C15-AB7F-5224EED5B0EA}.Release|x86.ActiveCfg = Release|Any CPU
+ {AE21D0EE-9A2C-4C15-AB7F-5224EED5B0EA}.Release|x86.Build.0 = Release|Any CPU
{BF62FE08-373A-43D6-9D73-41CAA38B7011}.Debug|x86.ActiveCfg = Debug|x86
{BF62FE08-373A-43D6-9D73-41CAA38B7011}.Debug|x86.Build.0 = Debug|x86
{BF62FE08-373A-43D6-9D73-41CAA38B7011}.Release|x86.ActiveCfg = Release|x86