Added providers for Box and Baidu (#179)

* Added project with provider for Box cloud service
* Added Baidu provider

.gitignore

@@ -70,6 +70,9 @@ ipch/
 # Guidance Automation Toolkit
 *.gpState
 
+# CodeRush is a .NET coding add-in
+.cr/
+
 # ReSharper is a .NET coding add-in
 _ReSharper*/
 *.[Rr]e[Ss]harper

OwinOAuthProviders.sln

@@ -1,6 +1,6 @@
 Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio 14
-VisualStudioVersion = 14.0.25123.0
+VisualStudioVersion = 14.0.25420.1
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Owin.Security.Providers.ArcGISOnline", "src\Owin.Security.Providers.ArcGISOnline\Owin.Security.Providers.ArcGISOnline.csproj", "{8A49FAEF-D365-4D25-942C-1CAD03845A5E}"
 EndProject
@@ -100,6 +100,10 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Owin.Security.Providers.Gen
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Owin.Security.Providers.MyHeritage", "src\Owin.Security.Providers.MyHeritage\Owin.Security.Providers.MyHeritage.csproj", "{84795078-31B5-4369-BD1B-F960165F8C71}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Owin.Security.Providers.Box", "src\Owin.Security.Providers.Box\Owin.Security.Providers.Box.csproj", "{1AEF8813-E1F9-41E1-BC8D-732960595E9F}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Owin.Security.Providers.Baidu", "src\Owin.Security.Providers.Baidu\Owin.Security.Providers.Baidu.csproj", "{E2759807-4D7C-4288-AAC8-F5B7B4616680}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -302,6 +306,14 @@ Global
 		{84795078-31B5-4369-BD1B-F960165F8C71}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{84795078-31B5-4369-BD1B-F960165F8C71}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{84795078-31B5-4369-BD1B-F960165F8C71}.Release|Any CPU.Build.0 = Release|Any CPU
+		{1AEF8813-E1F9-41E1-BC8D-732960595E9F}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{1AEF8813-E1F9-41E1-BC8D-732960595E9F}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{1AEF8813-E1F9-41E1-BC8D-732960595E9F}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{1AEF8813-E1F9-41E1-BC8D-732960595E9F}.Release|Any CPU.Build.0 = Release|Any CPU
+		{E2759807-4D7C-4288-AAC8-F5B7B4616680}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{E2759807-4D7C-4288-AAC8-F5B7B4616680}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{E2759807-4D7C-4288-AAC8-F5B7B4616680}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{E2759807-4D7C-4288-AAC8-F5B7B4616680}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

OwinOAuthProvidersDemo/App_Start/Startup.Auth.cs

@@ -3,9 +3,6 @@ using Microsoft.Owin;
 using Microsoft.Owin.Security.Cookies;
 using Owin;
 
-//using Owin.Security.Providers.Orcid;
-//using Owin.Security.Providers.Discord;
-
 namespace OwinOAuthProvidersDemo
 {
 	public partial class Startup
@@ -168,6 +165,14 @@ namespace OwinOAuthProvidersDemo
             //    clientId: "",
             //    clientSecret: "");
 
+            //app.UseBoxAuthentication(
+            //    appKey: "",
+            //    appSecret: "");
+
+            //app.UseBaiduAuthentication(
+            //    apiKey: "",
+            //    secretKey: "");
+
             //app.UseBattleNetAuthentication(new BattleNetAuthenticationOptions
             //{
             //	ClientId = "",

src/Owin.Security.Providers.Baidu/BaiduAuthenticationExtensions.cs

@@ -0,0 +1,29 @@
+using System;
+
+namespace Owin.Security.Providers.Baidu
+{
+    public static class BaiduAuthenticationExtensions
+    {
+        public static IAppBuilder UseBaiduAuthentication(this IAppBuilder app,
+            BaiduAuthenticationOptions options)
+        {
+            if (app == null)
+                throw new ArgumentNullException(nameof(app));
+            if (options == null)
+                throw new ArgumentNullException(nameof(options));
+
+            app.Use(typeof(BaiduAuthenticationMiddleware), app, options);
+
+            return app;
+        }
+
+        public static IAppBuilder UseBaiduAuthentication(this IAppBuilder app, string apiKey, string secretKey)
+        {
+            return app.UseBaiduAuthentication(new BaiduAuthenticationOptions
+            {
+                ApiKey = apiKey,
+                SecretKey = secretKey
+            });
+        }
+    }
+}

src/Owin.Security.Providers.Baidu/BaiduAuthenticationHandler.cs

@@ -0,0 +1,236 @@
+using System;
+using System.Collections.Generic;
+using System.Net.Http;
+using System.Security.Claims;
+using System.Threading.Tasks;
+using Microsoft.Owin;
+using Microsoft.Owin.Infrastructure;
+using Microsoft.Owin.Logging;
+using Microsoft.Owin.Security;
+using Microsoft.Owin.Security.Infrastructure;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+using System.Net.Http.Headers;
+
+namespace Owin.Security.Providers.Baidu
+{
+    public class BaiduAuthenticationHandler : AuthenticationHandler<BaiduAuthenticationOptions>
+    {
+        private const string StateCookie = "_BaiduState";
+        private const string XmlSchemaString = "http://www.w3.org/2001/XMLSchema#string";
+        private const string TokenEndpoint = "https://openapi.baidu.com/oauth/2.0/token";
+        private const string UserInfoEndpoint = "https://openapi.baidu.com/rest/2.0/passport/users/getInfo";
+        private const string AuthEndpoint = "http://openapi.baidu.com/oauth/2.0/authorize";
+
+        private readonly ILogger _logger;
+        private readonly HttpClient _httpClient;
+
+        public BaiduAuthenticationHandler(HttpClient httpClient, ILogger logger)
+        {
+            _httpClient = httpClient;
+            _logger = logger;
+        }
+
+        protected override async Task<AuthenticationTicket> AuthenticateCoreAsync()
+        {
+            AuthenticationProperties properties = null;
+
+            try
+            {
+                string code = null;
+
+                var query = Request.Query;
+                var values = query.GetValues("code");
+                if (values != null && values.Count == 1)
+                {
+                    code = values[0];
+                }
+
+                var state = Request.Cookies[StateCookie];
+                properties = Options.StateDataFormat.Unprotect(state);
+                if (properties == null)
+                {
+                    return null;
+                }
+
+                // OAuth2 10.12 CSRF
+                if (!ValidateCorrelationId(properties, _logger))
+                {
+                    return new AuthenticationTicket(null, properties);
+                }
+
+                // Check for error
+                if (Request.Query.Get("error") != null)
+                    return new AuthenticationTicket(null, properties);
+
+                var requestPrefix = Request.Scheme + "://" + Request.Host;
+                var redirectUri = requestPrefix + Request.PathBase + Options.CallbackPath;
+
+                // Build up the body for the token request
+                var body = new List<KeyValuePair<string, string>>
+                {
+                    new KeyValuePair<string, string>("grant_type", "authorization_code"),
+                    new KeyValuePair<string, string>("code", code),
+                    new KeyValuePair<string, string>("redirect_uri", redirectUri),
+                    new KeyValuePair<string, string>("client_id", Options.ApiKey),
+                    new KeyValuePair<string, string>("client_secret", Options.SecretKey)
+                };
+
+                // Request the token
+                var tokenResponse =
+                    await _httpClient.PostAsync(TokenEndpoint, new FormUrlEncodedContent(body));
+                tokenResponse.EnsureSuccessStatusCode();
+                var text = await tokenResponse.Content.ReadAsStringAsync();
+
+                // Deserializes the token response
+                dynamic response = JsonConvert.DeserializeObject<dynamic>(text);
+                var accessToken = (string)response.access_token;
+
+                // Get the Baidu user
+                // http://developer.baidu.com/wiki/index.php?title=docs/oauth/rest/file_data_apis_list#.E8.BF.94.E5.9B.9E.E7.94.A8.E6.88.B7.E8.AF.A6.E7.BB.86.E8.B5.84.E6.96.99
+                var userResponse = await _httpClient.GetAsync(
+                    UserInfoEndpoint + "?access_token=" + Uri.EscapeDataString(accessToken), Request.CallCancelled);
+
+                userResponse.EnsureSuccessStatusCode();
+                text = await userResponse.Content.ReadAsStringAsync();
+                var user = JObject.Parse(text);
+
+                var context = new BaiduAuthenticatedContext(Context, user, accessToken)
+                {
+                    Identity = new ClaimsIdentity(
+                        Options.AuthenticationType,
+                        ClaimsIdentity.DefaultNameClaimType,
+                        ClaimsIdentity.DefaultRoleClaimType)
+                };
+                if (!string.IsNullOrEmpty(context.Userid))
+                {
+                    context.Identity.AddClaim(new Claim(ClaimTypes.NameIdentifier, context.Userid, XmlSchemaString, Options.AuthenticationType));
+                }
+                if (!string.IsNullOrEmpty(context.UserName))
+                {
+                    context.Identity.AddClaim(new Claim(ClaimsIdentity.DefaultNameClaimType, context.UserName, XmlSchemaString, Options.AuthenticationType));
+                }
+                context.Properties = properties;
+
+                await Options.Provider.Authenticated(context);
+
+                return new AuthenticationTicket(context.Identity, context.Properties);
+            }
+            catch (Exception ex)
+            {
+                _logger.WriteError(ex.Message);
+            }
+            return new AuthenticationTicket(null, properties);
+        }
+
+        protected override Task ApplyResponseChallengeAsync()
+        {
+            if (Response.StatusCode != 401)
+            {
+                return Task.FromResult<object>(null);
+            }
+
+            var challenge = Helper.LookupChallenge(Options.AuthenticationType, Options.AuthenticationMode);
+
+            if (challenge == null) return Task.FromResult<object>(null);
+            var baseUri =
+                Request.Scheme +
+                Uri.SchemeDelimiter +
+                Request.Host +
+                Request.PathBase;
+
+            var currentUri =
+                baseUri +
+                Request.Path +
+                Request.QueryString;
+
+            var redirectUri =
+                baseUri +
+                Options.CallbackPath;
+
+            var properties = challenge.Properties;
+            if (string.IsNullOrEmpty(properties.RedirectUri))
+            {
+                properties.RedirectUri = currentUri;
+            }
+
+            // OAuth2 10.12 CSRF
+            GenerateCorrelationId(properties);
+
+            // comma separated
+            var scope = string.Join(" ", Options.Scope);
+
+            var state = Options.StateDataFormat.Protect(properties);
+
+            var authorizationEndpoint =
+                AuthEndpoint +
+                "?response_type=code" +
+                "&client_id=" + Uri.EscapeDataString(Options.ApiKey) +
+                "&redirect_uri=" + Uri.EscapeDataString(redirectUri) +
+                "&scope=" + Uri.EscapeDataString(scope) +
+                "&state=" + Uri.EscapeDataString(state);
+
+            var cookieOptions = new CookieOptions
+            {
+                HttpOnly = true,
+                Secure = Request.IsSecure
+            };
+
+            Response.StatusCode = 302;
+            Response.Cookies.Append(StateCookie, Options.StateDataFormat.Protect(properties), cookieOptions);
+            Response.Headers.Set("Location", authorizationEndpoint);
+
+            return Task.FromResult<object>(null);
+        }
+
+        public override async Task<bool> InvokeAsync()
+        {
+            return await InvokeReplyPathAsync();
+        }
+
+        private async Task<bool> InvokeReplyPathAsync()
+        {
+            if (!Options.CallbackPath.HasValue || Options.CallbackPath != Request.Path) return false;
+            // TODO: error responses
+
+            var ticket = await AuthenticateAsync();
+            if (ticket == null)
+            {
+                _logger.WriteWarning("Invalid return state, unable to redirect.");
+                Response.StatusCode = 500;
+                return true;
+            }
+
+            var context = new BaiduReturnEndpointContext(Context, ticket)
+            {
+                SignInAsAuthenticationType = Options.SignInAsAuthenticationType,
+                RedirectUri = ticket.Properties.RedirectUri
+            };
+
+            await Options.Provider.ReturnEndpoint(context);
+
+            if (context.SignInAsAuthenticationType != null &&
+                context.Identity != null)
+            {
+                var grantIdentity = context.Identity;
+                if (!string.Equals(grantIdentity.AuthenticationType, context.SignInAsAuthenticationType, StringComparison.Ordinal))
+                {
+                    grantIdentity = new ClaimsIdentity(grantIdentity.Claims, context.SignInAsAuthenticationType, grantIdentity.NameClaimType, grantIdentity.RoleClaimType);
+                }
+                Context.Authentication.SignIn(context.Properties, grantIdentity);
+            }
+
+            if (context.IsRequestCompleted || context.RedirectUri == null) return context.IsRequestCompleted;
+            var redirectUri = context.RedirectUri;
+            if (context.Identity == null)
+            {
+                // add a redirect hint that sign-in failed in some way
+                redirectUri = WebUtilities.AddQueryString(redirectUri, "error", "access_denied");
+            }
+            Response.Redirect(redirectUri);
+            context.RequestCompleted();
+
+            return context.IsRequestCompleted;
+        }
+    }
+}

src/Owin.Security.Providers.Baidu/BaiduAuthenticationMiddleware.cs

@@ -0,0 +1,82 @@
+using System;
+using System.Globalization;
+using System.Net.Http;
+using Microsoft.Owin;
+using Microsoft.Owin.Logging;
+using Microsoft.Owin.Security;
+using Microsoft.Owin.Security.DataHandler;
+using Microsoft.Owin.Security.DataProtection;
+using Microsoft.Owin.Security.Infrastructure;
+
+namespace Owin.Security.Providers.Baidu
+{
+    public class BaiduAuthenticationMiddleware : AuthenticationMiddleware<BaiduAuthenticationOptions>
+    {
+        private readonly HttpClient _httpClient;
+        private readonly ILogger _logger;
+
+        public BaiduAuthenticationMiddleware(OwinMiddleware next, IAppBuilder app,
+            BaiduAuthenticationOptions options)
+            : base(next, options)
+        {
+            if (string.IsNullOrWhiteSpace(Options.ApiKey))
+                throw new ArgumentException(string.Format(CultureInfo.CurrentCulture,
+                    Resources.Exception_OptionMustBeProvided, nameof(Options.ApiKey)));
+            if (string.IsNullOrWhiteSpace(Options.SecretKey))
+                throw new ArgumentException(string.Format(CultureInfo.CurrentCulture,
+                    Resources.Exception_OptionMustBeProvided, nameof(Options.SecretKey)));
+
+            _logger = app.CreateLogger<BaiduAuthenticationMiddleware>();
+
+            if (Options.Provider == null)
+                Options.Provider = new BaiduAuthenticationProvider();
+
+            if (Options.StateDataFormat == null)
+            {
+                var dataProtector = app.CreateDataProtector(
+                    typeof (BaiduAuthenticationMiddleware).FullName,
+                    Options.AuthenticationType, "v1");
+                Options.StateDataFormat = new PropertiesDataFormat(dataProtector);
+            }
+
+            if (string.IsNullOrEmpty(Options.SignInAsAuthenticationType))
+                Options.SignInAsAuthenticationType = app.GetDefaultSignInAsAuthenticationType();
+
+            _httpClient = new HttpClient(ResolveHttpMessageHandler(Options))
+            {
+                Timeout = Options.BackchannelTimeout,
+                MaxResponseContentBufferSize = 1024*1024*10
+            };
+        }
+
+        /// <summary>
+        ///     Provides the <see cref="T:Microsoft.Owin.Security.Infrastructure.AuthenticationHandler" /> object for processing
+        ///     authentication-related requests.
+        /// </summary>
+        /// <returns>
+        ///     An <see cref="T:Microsoft.Owin.Security.Infrastructure.AuthenticationHandler" /> configured with the
+        ///     <see cref="T:Owin.Security.Providers.Baidu.BaiduAuthenticationOptions" /> supplied to the constructor.
+        /// </returns>
+        protected override AuthenticationHandler<BaiduAuthenticationOptions> CreateHandler()
+        {
+            return new BaiduAuthenticationHandler(_httpClient, _logger);
+        }
+
+        private static HttpMessageHandler ResolveHttpMessageHandler(BaiduAuthenticationOptions options)
+        {
+            var handler = options.BackchannelHttpHandler ?? new WebRequestHandler();
+
+            // If they provided a validator, apply it or fail.
+            if (options.BackchannelCertificateValidator == null) return handler;
+            // Set the cert validate callback
+            var webRequestHandler = handler as WebRequestHandler;
+            if (webRequestHandler == null)
+            {
+                throw new InvalidOperationException(Resources.Exception_ValidatorHandlerMismatch);
+            }
+            webRequestHandler.ServerCertificateValidationCallback = options.BackchannelCertificateValidator.Validate;
+
+            return handler;
+        }
+    }
+}

src/Owin.Security.Providers.Baidu/BaiduAuthenticationOptions.cs

@@ -0,0 +1,102 @@
+using System;
+using System.Net.Http;
+using Microsoft.Owin;
+using Microsoft.Owin.Security;
+using System.Collections.Generic;
+
+namespace Owin.Security.Providers.Baidu
+{
+    public class BaiduAuthenticationOptions : AuthenticationOptions
+    {
+        /// <summary>
+        ///     Gets or sets the a pinned certificate validator to use to validate the endpoints used
+        ///     in back channel communications belong to Baidu
+        /// </summary>
+        /// <value>
+        ///     The pinned certificate validator.
+        /// </value>
+        /// <remarks>
+        ///     If this property is null then the default certificate checks are performed,
+        ///     validating the subject name and if the signing chain is a trusted party.
+        /// </remarks>
+        public ICertificateValidator BackchannelCertificateValidator { get; set; }
+
+        /// <summary>
+        ///     The HttpMessageHandler used to communicate with Baidu.
+        ///     This cannot be set at the same time as BackchannelCertificateValidator unless the value
+        ///     can be downcast to a WebRequestHandler.
+        /// </summary>
+        public HttpMessageHandler BackchannelHttpHandler { get; set; }
+
+        /// <summary>
+        ///     Gets or sets timeout value in milliseconds for back channel communications with Baidu.
+        /// </summary>
+        /// <value>
+        ///     The back channel timeout in milliseconds.
+        /// </value>
+        public TimeSpan BackchannelTimeout { get; set; }
+
+        /// <summary>
+        ///     The request path within the application's base path where the user-agent will be returned.
+        ///     The middleware will process this request when it arrives.
+        ///     Default value is "/signin-dropbox".
+        /// </summary>
+        public PathString CallbackPath { get; set; }
+
+        /// <summary>
+        ///     Get or sets the text that the user can display on a sign in user interface.
+        /// </summary>
+        public string Caption
+        {
+            get { return Description.Caption; }
+            set { Description.Caption = value; }
+        }
+
+        /// <summary>
+        /// Gets or sets the Baidu supplied API Key
+        /// </summary>
+        public string ApiKey { get; set; }
+
+        /// <summary>
+        /// Gets or sets the Baidu supplied Secret Key
+        /// </summary>
+        public string SecretKey { get; set; }
+        
+        /// <summary>
+        /// A list of permissions to request.
+        /// </summary>
+        public IList<string> Scope { get; private set; }
+
+        /// <summary>
+        ///     Gets or sets the <see cref="IBaiduAuthenticationProvider" /> used in the authentication events
+        /// </summary>
+        public IBaiduAuthenticationProvider Provider { get; set; }
+
+        /// <summary>
+        ///     Gets or sets the name of another authentication middleware which will be responsible for actually issuing a user
+        ///     <see cref="System.Security.Claims.ClaimsIdentity" />.
+        /// </summary>
+        public string SignInAsAuthenticationType { get; set; }
+
+        /// <summary>
+        ///     Gets or sets the type used to secure data handled by the middleware.
+        /// </summary>
+        public ISecureDataFormat<AuthenticationProperties> StateDataFormat { get; set; }
+
+        /// <summary>
+        ///     Initializes a new <see cref="BaiduAuthenticationOptions" />
+        /// </summary>
+        public BaiduAuthenticationOptions()
+            : base("Baidu")
+        {
+            Caption = Constants.DefaultAuthenticationType;
+            CallbackPath = new PathString("/signin-baidu");
+            AuthenticationMode = AuthenticationMode.Passive;
+            Scope = new List<string>
+            {
+                "basic"
+            };
+            BackchannelTimeout = TimeSpan.FromSeconds(60);
+        }
+    }
+}

src/Owin.Security.Providers.Baidu/Constants.cs

@@ -0,0 +1,7 @@
+namespace Owin.Security.Providers.Baidu
+{
+    internal static class Constants
+    {
+        public const string DefaultAuthenticationType = "Baidu";
+    }
+}

src/Owin.Security.Providers.Baidu/Owin.Security.Providers.Baidu.csproj

@@ -0,0 +1,102 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="14.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
+  <PropertyGroup>
+    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
+    <ProjectGuid>{E2759807-4D7C-4288-AAC8-F5B7B4616680}</ProjectGuid>
+    <OutputType>Library</OutputType>
+    <AppDesignerFolder>Properties</AppDesignerFolder>
+    <RootNamespace>Owin.Security.Providers.Baidu</RootNamespace>
+    <AssemblyName>Owin.Security.Providers.Baidu</AssemblyName>
+    <TargetFrameworkVersion>v4.5</TargetFrameworkVersion>
+    <FileAlignment>512</FileAlignment>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>full</DebugType>
+    <Optimize>false</Optimize>
+    <OutputPath>bin\Debug\</OutputPath>
+    <DefineConstants>DEBUG;TRACE</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <OutputPath>bin\Release\</OutputPath>
+    <DefineConstants>TRACE</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+  </PropertyGroup>
+  <ItemGroup>
+    <Reference Include="Microsoft.Owin, Version=3.0.1.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\Microsoft.Owin.3.0.1\lib\net45\Microsoft.Owin.dll</HintPath>
+      <Private>True</Private>
+    </Reference>
+    <Reference Include="Microsoft.Owin.Security, Version=3.0.1.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\Microsoft.Owin.Security.3.0.1\lib\net45\Microsoft.Owin.Security.dll</HintPath>
+      <Private>True</Private>
+    </Reference>
+    <Reference Include="Newtonsoft.Json, Version=8.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\Newtonsoft.Json.8.0.3\lib\net45\Newtonsoft.Json.dll</HintPath>
+      <Private>True</Private>
+    </Reference>
+    <Reference Include="Owin, Version=1.0.0.0, Culture=neutral, PublicKeyToken=f0ebd12fd5e55cc5, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\Owin.1.0\lib\net40\Owin.dll</HintPath>
+      <Private>True</Private>
+    </Reference>
+    <Reference Include="System" />
+    <Reference Include="System.Core" />
+    <Reference Include="System.Net.Http.WebRequest" />
+    <Reference Include="System.Xml.Linq" />
+    <Reference Include="System.Data.DataSetExtensions" />
+    <Reference Include="Microsoft.CSharp" />
+    <Reference Include="System.Data" />
+    <Reference Include="System.Net.Http" />
+    <Reference Include="System.Xml" />
+  </ItemGroup>
+  <ItemGroup>
+    <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="Constants.cs" />
+    <Compile Include="BaiduAuthenticationExtensions.cs" />
+    <Compile Include="BaiduAuthenticationHandler.cs" />
+    <Compile Include="BaiduAuthenticationMiddleware.cs" />
+    <Compile Include="BaiduAuthenticationOptions.cs" />
+    <Compile Include="Provider\BaiduAuthenticatedContext.cs" />
+    <Compile Include="Provider\BaiduAuthenticationProvider.cs" />
+    <Compile Include="Provider\BaiduReturnEndpointContext.cs" />
+    <Compile Include="Provider\IBaiduAuthenticationProvider.cs" />
+    <Compile Include="Resources.Designer.cs">
+      <DependentUpon>Resources.resx</DependentUpon>
+      <AutoGen>True</AutoGen>
+      <DesignTime>True</DesignTime>
+    </Compile>
+  </ItemGroup>
+  <ItemGroup>
+    <EmbeddedResource Include="Resources.resx">
+      <Generator>ResXFileCodeGenerator</Generator>
+      <LastGenOutput>Resources.Designer.cs</LastGenOutput>
+    </EmbeddedResource>
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="packages.config" />
+  </ItemGroup>
+  <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
+  <Target Name="PostBuildMacros">
+    <GetAssemblyIdentity AssemblyFiles="$(TargetPath)">
+      <Output TaskParameter="Assemblies" ItemName="Targets" />
+    </GetAssemblyIdentity>
+    <ItemGroup>
+      <VersionNumber Include="@(Targets->'%(Version)')" />
+    </ItemGroup>
+  </Target>
+  <PropertyGroup>
+    <PreBuildEvent>
+    </PreBuildEvent>
+    <PostBuildEventDependsOn>
+      $(PostBuildEventDependsOn);
+      PostBuildMacros;
+    </PostBuildEventDependsOn>
+  </PropertyGroup>
+</Project>

src/Owin.Security.Providers.Baidu/Properties/AssemblyInfo.cs

@@ -0,0 +1,15 @@
+using System.Reflection;
+using System.Runtime.InteropServices;
+
+[assembly: AssemblyTitle("Owin.Security.Providers.Baidu")]
+[assembly: AssemblyDescription("")]
+[assembly: AssemblyConfiguration("")]
+[assembly: AssemblyCompany("")]
+[assembly: AssemblyProduct("Owin.Security.Providers.Baidu")]
+[assembly: AssemblyCopyright("Copyright ©  2016")]
+[assembly: AssemblyTrademark("")]
+[assembly: AssemblyCulture("")]
+[assembly: ComVisible(false)]
+[assembly: Guid("AD2018C1-FA82-4DC3-8CD4-BCC4D232A678")]
+[assembly: AssemblyVersion("2.0.0.0")]
+[assembly: AssemblyFileVersion("2.0.0.0")]

src/Owin.Security.Providers.Baidu/Provider/BaiduAuthenticatedContext.cs

@@ -0,0 +1,77 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.txt in the project root for license information.
+
+using System.Security.Claims;
+using Microsoft.Owin;
+using Microsoft.Owin.Security;
+using Microsoft.Owin.Security.Provider;
+using Newtonsoft.Json.Linq;
+
+namespace Owin.Security.Providers.Baidu
+{
+    /// <summary>
+    /// Contains information about the login session as well as the user <see cref="System.Security.Claims.ClaimsIdentity"/>.
+    /// </summary>
+    public class BaiduAuthenticatedContext : BaseContext
+    {
+        /// <summary>
+        /// Initializes a <see cref="BaiduAuthenticatedContext"/>
+        /// </summary>
+        /// <param name="context">The OWIN environment</param>
+        /// <param name="user">The JSON-serialized user</param>
+        /// <param name="accessToken">Baidu Access token</param>
+        public BaiduAuthenticatedContext(IOwinContext context, JObject user, string accessToken)
+            : base(context)
+        {
+            AccessToken = accessToken;
+            User = user;
+
+            Userid = TryGetValue(user, "userid");
+            UserName = TryGetValue(user, "username");
+            RealName = TryGetValue(user, "realname");
+        }
+
+        /// <summary>
+        /// Gets the JSON-serialized user
+        /// </summary>
+        /// <remarks>
+        /// Contains the Baidu user obtained from the endpoint https://api.dropbox.com/1/account/info
+        /// </remarks>
+        public JObject User { get; private set; }
+
+        /// <summary>
+        /// Gets the Baidu OAuth access token
+        /// </summary>
+        public string AccessToken { get; private set; }
+
+        /// <summary>
+        /// Gets the Baidu user ID
+        /// </summary>
+        public string Userid { get; private set; }
+
+        /// <summary>
+        /// The name of the user
+        /// </summary>
+        public string UserName { get; private set; }
+
+        /// <summary>
+        /// The real name of the user
+        /// </summary>
+        public string RealName { get; private set; }
+
+        /// <summary>
+        /// Gets the <see cref="ClaimsIdentity"/> representing the user
+        /// </summary>
+        public ClaimsIdentity Identity { get; set; }
+
+        /// <summary>
+        /// Gets or sets a property bag for common authentication properties
+        /// </summary>
+        public AuthenticationProperties Properties { get; set; }
+
+        private static string TryGetValue(JObject user, string propertyName)
+        {
+            JToken value;
+            return user.TryGetValue(propertyName, out value) ? value.ToString() : null;
+        }
+    }
+}

src/Owin.Security.Providers.Baidu/Provider/BaiduAuthenticationProvider.cs

@@ -0,0 +1,50 @@
+using System;
+using System.Threading.Tasks;
+
+namespace Owin.Security.Providers.Baidu
+{
+    /// <summary>
+    /// Default <see cref="IBaiduAuthenticationProvider"/> implementation.
+    /// </summary>
+    public class BaiduAuthenticationProvider : IBaiduAuthenticationProvider
+    {
+        /// <summary>
+        /// Initializes a <see cref="BaiduAuthenticationProvider"/>
+        /// </summary>
+        public BaiduAuthenticationProvider()
+        {
+            OnAuthenticated = context => Task.FromResult<object>(null);
+            OnReturnEndpoint = context => Task.FromResult<object>(null);
+        }
+
+        /// <summary>
+        /// Gets or sets the function that is invoked when the Authenticated method is invoked.
+        /// </summary>
+        public Func<BaiduAuthenticatedContext, Task> OnAuthenticated { get; set; }
+
+        /// <summary>
+        /// Gets or sets the function that is invoked when the ReturnEndpoint method is invoked.
+        /// </summary>
+        public Func<BaiduReturnEndpointContext, Task> OnReturnEndpoint { get; set; }
+
+        /// <summary>
+        /// Invoked whenever Baidu successfully authenticates a user
+        /// </summary>
+        /// <param name="context">Contains information about the login session as well as the user <see cref="System.Security.Claims.ClaimsIdentity"/>.</param>
+        /// <returns>A <see cref="Task"/> representing the completed operation.</returns>
+        public virtual Task Authenticated(BaiduAuthenticatedContext context)
+        {
+            return OnAuthenticated(context);
+        }
+
+        /// <summary>
+        /// Invoked prior to the <see cref="System.Security.Claims.ClaimsIdentity"/> being saved in a local cookie and the browser being redirected to the originally requested URL.
+        /// </summary>
+        /// <param name="context"></param>
+        /// <returns>A <see cref="Task"/> representing the completed operation.</returns>
+        public virtual Task ReturnEndpoint(BaiduReturnEndpointContext context)
+        {
+            return OnReturnEndpoint(context);
+        }
+    }
+}

src/Owin.Security.Providers.Baidu/Provider/BaiduReturnEndpointContext.cs

@@ -0,0 +1,26 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.txt in the project root for license information.
+
+using Microsoft.Owin;
+using Microsoft.Owin.Security;
+using Microsoft.Owin.Security.Provider;
+
+namespace Owin.Security.Providers.Baidu
+{
+    /// <summary>
+    /// Provides context information to middleware providers.
+    /// </summary>
+    public class BaiduReturnEndpointContext : ReturnEndpointContext
+    {
+        /// <summary>
+        /// 
+        /// </summary>
+        /// <param name="context">OWIN environment</param>
+        /// <param name="ticket">The authentication ticket</param>
+        public BaiduReturnEndpointContext(
+            IOwinContext context,
+            AuthenticationTicket ticket)
+            : base(context, ticket)
+        {
+        }
+    }
+}

src/Owin.Security.Providers.Baidu/Provider/IBaiduAuthenticationProvider.cs

@@ -0,0 +1,24 @@
+using System.Threading.Tasks;
+
+namespace Owin.Security.Providers.Baidu
+{
+    /// <summary>
+    /// Specifies callback methods which the <see cref="BaiduAuthenticationMiddleware"></see> invokes to enable developer control over the authentication process. />
+    /// </summary>
+    public interface IBaiduAuthenticationProvider
+    {
+        /// <summary>
+        /// Invoked whenever Baidu successfully authenticates a user
+        /// </summary>
+        /// <param name="context">Contains information about the login session as well as the user <see cref="System.Security.Claims.ClaimsIdentity"/>.</param>
+        /// <returns>A <see cref="Task"/> representing the completed operation.</returns>
+        Task Authenticated(BaiduAuthenticatedContext context);
+
+        /// <summary>
+        /// Invoked prior to the <see cref="System.Security.Claims.ClaimsIdentity"/> being saved in a local cookie and the browser being redirected to the originally requested URL.
+        /// </summary>
+        /// <param name="context"></param>
+        /// <returns>A <see cref="Task"/> representing the completed operation.</returns>
+        Task ReturnEndpoint(BaiduReturnEndpointContext context);
+    }
+}

src/Owin.Security.Providers.Baidu/Resources.Designer.cs

@@ -0,0 +1,81 @@
+//------------------------------------------------------------------------------
+// <auto-generated>
+//     This code was generated by a tool.
+//     Runtime Version:4.0.30319.42000
+//
+//     Changes to this file may cause incorrect behavior and will be lost if
+//     the code is regenerated.
+// </auto-generated>
+//------------------------------------------------------------------------------
+
+namespace Owin.Security.Providers.Baidu {
+    using System;
+    
+    
+    /// <summary>
+    ///   A strongly-typed resource class, for looking up localized strings, etc.
+    /// </summary>
+    // This class was auto-generated by the StronglyTypedResourceBuilder
+    // class via a tool like ResGen or Visual Studio.
+    // To add or remove a member, edit your .ResX file then rerun ResGen
+    // with the /str option, or rebuild your VS project.
+    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("System.Resources.Tools.StronglyTypedResourceBuilder", "4.0.0.0")]
+    [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]
+    [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]
+    internal class Resources {
+        
+        private static global::System.Resources.ResourceManager resourceMan;
+        
+        private static global::System.Globalization.CultureInfo resourceCulture;
+        
+        [global::System.Diagnostics.CodeAnalysis.SuppressMessageAttribute("Microsoft.Performance", "CA1811:AvoidUncalledPrivateCode")]
+        internal Resources() {
+        }
+        
+        /// <summary>
+        ///   Returns the cached ResourceManager instance used by this class.
+        /// </summary>
+        [global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Advanced)]
+        internal static global::System.Resources.ResourceManager ResourceManager {
+            get {
+                if (object.ReferenceEquals(resourceMan, null)) {
+                    global::System.Resources.ResourceManager temp = new global::System.Resources.ResourceManager("Owin.Security.Providers.Baidu.Resources", typeof(Resources).Assembly);
+                    resourceMan = temp;
+                }
+                return resourceMan;
+            }
+        }
+        
+        /// <summary>
+        ///   Overrides the current thread's CurrentUICulture property for all
+        ///   resource lookups using this strongly typed resource class.
+        /// </summary>
+        [global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Advanced)]
+        internal static global::System.Globalization.CultureInfo Culture {
+            get {
+                return resourceCulture;
+            }
+            set {
+                resourceCulture = value;
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to The &apos;{0}&apos; option must be provided..
+        /// </summary>
+        internal static string Exception_OptionMustBeProvided {
+            get {
+                return ResourceManager.GetString("Exception_OptionMustBeProvided", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to An ICertificateValidator cannot be specified at the same time as an HttpMessageHandler unless it is a WebRequestHandler..
+        /// </summary>
+        internal static string Exception_ValidatorHandlerMismatch {
+            get {
+                return ResourceManager.GetString("Exception_ValidatorHandlerMismatch", resourceCulture);
+            }
+        }
+    }
+}

src/Owin.Security.Providers.Baidu/Resources.resx

@@ -0,0 +1,126 @@
+<?xml version="1.0" encoding="utf-8"?>
+<root>
+  <!-- 
+    Microsoft ResX Schema 
+    
+    Version 2.0
+    
+    The primary goals of this format is to allow a simple XML format 
+    that is mostly human readable. The generation and parsing of the 
+    various data types are done through the TypeConverter classes 
+    associated with the data types.
+    
+    Example:
+    
+    ... ado.net/XML headers & schema ...
+    <resheader name="resmimetype">text/microsoft-resx</resheader>
+    <resheader name="version">2.0</resheader>
+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
+    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>
+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
+        <value>[base64 mime encoded serialized .NET Framework object]</value>
+    </data>
+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
+        <comment>This is a comment</comment>
+    </data>
+                
+    There are any number of "resheader" rows that contain simple 
+    name/value pairs.
+    
+    Each data row contains a name, and value. The row also contains a 
+    type or mimetype. Type corresponds to a .NET class that support 
+    text/value conversion through the TypeConverter architecture. 
+    Classes that don't support this are serialized and stored with the 
+    mimetype set.
+    
+    The mimetype is used for serialized objects, and tells the 
+    ResXResourceReader how to depersist the object. This is currently not 
+    extensible. For a given mimetype the value must be set accordingly:
+    
+    Note - application/x-microsoft.net.object.binary.base64 is the format 
+    that the ResXResourceWriter will generate, however the reader can 
+    read any of the formats listed below.
+    
+    mimetype: application/x-microsoft.net.object.binary.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
+            : and then encoded with base64 encoding.
+    
+    mimetype: application/x-microsoft.net.object.soap.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
+            : and then encoded with base64 encoding.
+
+    mimetype: application/x-microsoft.net.object.bytearray.base64
+    value   : The object must be serialized into a byte array 
+            : using a System.ComponentModel.TypeConverter
+            : and then encoded with base64 encoding.
+    -->
+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
+    <xsd:element name="root" msdata:IsDataSet="true">
+      <xsd:complexType>
+        <xsd:choice maxOccurs="unbounded">
+          <xsd:element name="metadata">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" />
+              </xsd:sequence>
+              <xsd:attribute name="name" use="required" type="xsd:string" />
+              <xsd:attribute name="type" type="xsd:string" />
+              <xsd:attribute name="mimetype" type="xsd:string" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="assembly">
+            <xsd:complexType>
+              <xsd:attribute name="alias" type="xsd:string" />
+              <xsd:attribute name="name" type="xsd:string" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="data">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />
+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />
+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="resheader">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" />
+            </xsd:complexType>
+          </xsd:element>
+        </xsd:choice>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:schema>
+  <resheader name="resmimetype">
+    <value>text/microsoft-resx</value>
+  </resheader>
+  <resheader name="version">
+    <value>2.0</value>
+  </resheader>
+  <resheader name="reader">
+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <resheader name="writer">
+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <data name="Exception_OptionMustBeProvided" xml:space="preserve">
+    <value>The '{0}' option must be provided.</value>
+  </data>
+  <data name="Exception_ValidatorHandlerMismatch" xml:space="preserve">
+    <value>An ICertificateValidator cannot be specified at the same time as an HttpMessageHandler unless it is a WebRequestHandler.</value>
+  </data>
+</root>

src/Owin.Security.Providers.Baidu/packages.config

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="Microsoft.Owin" version="3.0.1" targetFramework="net45" />
+  <package id="Microsoft.Owin.Security" version="3.0.1" targetFramework="net45" />
+  <package id="Newtonsoft.Json" version="8.0.3" targetFramework="net45" />
+  <package id="Owin" version="1.0" targetFramework="net45" />
+</packages>

src/Owin.Security.Providers.Box/BoxAuthenticationExtensions.cs

@@ -0,0 +1,29 @@
+using System;
+
+namespace Owin.Security.Providers.Box
+{
+    public static class BoxAuthenticationExtensions
+    {
+        public static IAppBuilder UseBoxAuthentication(this IAppBuilder app,
+            BoxAuthenticationOptions options)
+        {
+            if (app == null)
+                throw new ArgumentNullException(nameof(app));
+            if (options == null)
+                throw new ArgumentNullException(nameof(options));
+
+            app.Use(typeof(BoxAuthenticationMiddleware), app, options);
+
+            return app;
+        }
+
+        public static IAppBuilder UseBoxAuthentication(this IAppBuilder app, string appKey, string appSecret)
+        {
+            return app.UseBoxAuthentication(new BoxAuthenticationOptions
+            {
+                ClientId = appKey,
+                ClientSecret = appSecret
+            });
+        }
+    }
+}

src/Owin.Security.Providers.Box/BoxAuthenticationHandler.cs

@@ -0,0 +1,230 @@
+using System;
+using System.Collections.Generic;
+using System.Net.Http;
+using System.Security.Claims;
+using System.Threading.Tasks;
+using Microsoft.Owin;
+using Microsoft.Owin.Infrastructure;
+using Microsoft.Owin.Logging;
+using Microsoft.Owin.Security;
+using Microsoft.Owin.Security.Infrastructure;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+using System.Net.Http.Headers;
+
+namespace Owin.Security.Providers.Box
+{
+    public class BoxAuthenticationHandler : AuthenticationHandler<BoxAuthenticationOptions>
+    {
+        private const string StateCookie = "_BoxState";
+        private const string XmlSchemaString = "http://www.w3.org/2001/XMLSchema#string";
+        private const string TokenEndpoint = "https://api.box.com/oauth2/token";
+        private const string UserInfoEndpoint = "https://api.box.com/2.0/users/me";
+
+        private readonly ILogger _logger;
+        private readonly HttpClient _httpClient;
+
+        public BoxAuthenticationHandler(HttpClient httpClient, ILogger logger)
+        {
+            _httpClient = httpClient;
+            _logger = logger;
+        }
+
+        protected override async Task<AuthenticationTicket> AuthenticateCoreAsync()
+        {
+            AuthenticationProperties properties = null;
+
+            try
+            {
+                string code = null;
+
+                var query = Request.Query;
+                var values = query.GetValues("code");
+                if (values != null && values.Count == 1)
+                {
+                    code = values[0];
+                }
+
+                var state = Request.Cookies[StateCookie];
+                properties = Options.StateDataFormat.Unprotect(state);
+                if (properties == null)
+                {
+                    return null;
+                }
+
+                // OAuth2 10.12 CSRF
+                if (!ValidateCorrelationId(properties, _logger))
+                {
+                    return new AuthenticationTicket(null, properties);
+                }
+
+                // Check for error
+                if (Request.Query.Get("error") != null)
+                    return new AuthenticationTicket(null, properties);
+
+                var requestPrefix = Request.Scheme + "://" + Request.Host;
+                var redirectUri = requestPrefix + Request.PathBase + Options.CallbackPath;
+
+                // Build up the body for the token request
+                var body = new List<KeyValuePair<string, string>>
+                {
+                    new KeyValuePair<string, string>("grant_type", "authorization_code"),
+                    new KeyValuePair<string, string>("code", code),
+                    new KeyValuePair<string, string>("redirect_uri", redirectUri),
+                    new KeyValuePair<string, string>("client_id", Options.ClientId),
+                    new KeyValuePair<string, string>("client_secret", Options.ClientSecret)
+                };
+
+                // Request the token
+                var tokenResponse =
+                    await _httpClient.PostAsync(TokenEndpoint, new FormUrlEncodedContent(body));
+                tokenResponse.EnsureSuccessStatusCode();
+                var text = await tokenResponse.Content.ReadAsStringAsync();
+
+                // Deserializes the token response
+                dynamic response = JsonConvert.DeserializeObject<dynamic>(text);
+                var accessToken = (string)response.access_token;
+
+                // Get the Box user
+                // https://docs.box.com/reference#get-the-current-users-information
+                var userRequest = new HttpRequestMessage(HttpMethod.Get, UserInfoEndpoint);
+                userRequest.Headers.Authorization = new AuthenticationHeaderValue("Bearer", accessToken);
+                userRequest.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
+                var userResponse = await _httpClient.SendAsync(userRequest, Request.CallCancelled);
+                userResponse.EnsureSuccessStatusCode();
+                text = await userResponse.Content.ReadAsStringAsync();
+                var user = JObject.Parse(text);
+
+                var context = new BoxAuthenticatedContext(Context, user, accessToken)
+                {
+                    Identity = new ClaimsIdentity(
+                        Options.AuthenticationType,
+                        ClaimsIdentity.DefaultNameClaimType,
+                        ClaimsIdentity.DefaultRoleClaimType)
+                };
+                if (!string.IsNullOrEmpty(context.Id))
+                {
+                    context.Identity.AddClaim(new Claim(ClaimTypes.NameIdentifier, context.Id, XmlSchemaString, Options.AuthenticationType));
+                }
+                if (!string.IsNullOrEmpty(context.Name))
+                {
+                    context.Identity.AddClaim(new Claim(ClaimsIdentity.DefaultNameClaimType, context.Name, XmlSchemaString, Options.AuthenticationType));
+                }
+                context.Properties = properties;
+
+                await Options.Provider.Authenticated(context);
+
+                return new AuthenticationTicket(context.Identity, context.Properties);
+            }
+            catch (Exception ex)
+            {
+                _logger.WriteError(ex.Message);
+            }
+            return new AuthenticationTicket(null, properties);
+        }
+
+        protected override Task ApplyResponseChallengeAsync()
+        {
+            if (Response.StatusCode != 401)
+            {
+                return Task.FromResult<object>(null);
+            }
+
+            var challenge = Helper.LookupChallenge(Options.AuthenticationType, Options.AuthenticationMode);
+
+            if (challenge == null) return Task.FromResult<object>(null);
+            var baseUri =
+                Request.Scheme +
+                Uri.SchemeDelimiter +
+                Request.Host +
+                Request.PathBase;
+
+            var currentUri =
+                baseUri +
+                Request.Path +
+                Request.QueryString;
+
+            var redirectUri =
+                baseUri +
+                Options.CallbackPath;
+
+            var properties = challenge.Properties;
+            if (string.IsNullOrEmpty(properties.RedirectUri))
+            {
+                properties.RedirectUri = currentUri;
+            }
+
+            // OAuth2 10.12 CSRF
+            GenerateCorrelationId(properties);
+
+            var authorizationEndpoint =
+                "https://api.box.com/oauth2/authorize" +
+                "?response_type=code" +
+                "&client_id=" + Uri.EscapeDataString(Options.ClientId) +
+                "&state=authenticated" +
+                "&redirect_uri=" + Uri.EscapeDataString(redirectUri);
+
+            var cookieOptions = new CookieOptions
+            {
+                HttpOnly = true,
+                Secure = Request.IsSecure
+            };
+
+            Response.StatusCode = 302;
+            Response.Cookies.Append(StateCookie, Options.StateDataFormat.Protect(properties), cookieOptions);
+            Response.Headers.Set("Location", authorizationEndpoint);
+
+            return Task.FromResult<object>(null);
+        }
+
+        public override async Task<bool> InvokeAsync()
+        {
+            return await InvokeReplyPathAsync();
+        }
+
+        private async Task<bool> InvokeReplyPathAsync()
+        {
+            if (!Options.CallbackPath.HasValue || Options.CallbackPath != Request.Path) return false;
+            // TODO: error responses
+
+            var ticket = await AuthenticateAsync();
+            if (ticket == null)
+            {
+                _logger.WriteWarning("Invalid return state, unable to redirect.");
+                Response.StatusCode = 500;
+                return true;
+            }
+
+            var context = new BoxReturnEndpointContext(Context, ticket)
+            {
+                SignInAsAuthenticationType = Options.SignInAsAuthenticationType,
+                RedirectUri = ticket.Properties.RedirectUri
+            };
+
+            await Options.Provider.ReturnEndpoint(context);
+
+            if (context.SignInAsAuthenticationType != null &&
+                context.Identity != null)
+            {
+                var grantIdentity = context.Identity;
+                if (!string.Equals(grantIdentity.AuthenticationType, context.SignInAsAuthenticationType, StringComparison.Ordinal))
+                {
+                    grantIdentity = new ClaimsIdentity(grantIdentity.Claims, context.SignInAsAuthenticationType, grantIdentity.NameClaimType, grantIdentity.RoleClaimType);
+                }
+                Context.Authentication.SignIn(context.Properties, grantIdentity);
+            }
+
+            if (context.IsRequestCompleted || context.RedirectUri == null) return context.IsRequestCompleted;
+            var redirectUri = context.RedirectUri;
+            if (context.Identity == null)
+            {
+                // add a redirect hint that sign-in failed in some way
+                redirectUri = WebUtilities.AddQueryString(redirectUri, "error", "access_denied");
+            }
+            Response.Redirect(redirectUri);
+            context.RequestCompleted();
+
+            return context.IsRequestCompleted;
+        }
+    }
+}

src/Owin.Security.Providers.Box/BoxAuthenticationMiddleware.cs

@@ -0,0 +1,82 @@
+using System;
+using System.Globalization;
+using System.Net.Http;
+using Microsoft.Owin;
+using Microsoft.Owin.Logging;
+using Microsoft.Owin.Security;
+using Microsoft.Owin.Security.DataHandler;
+using Microsoft.Owin.Security.DataProtection;
+using Microsoft.Owin.Security.Infrastructure;
+
+namespace Owin.Security.Providers.Box
+{
+    public class BoxAuthenticationMiddleware : AuthenticationMiddleware<BoxAuthenticationOptions>
+    {
+        private readonly HttpClient _httpClient;
+        private readonly ILogger _logger;
+
+        public BoxAuthenticationMiddleware(OwinMiddleware next, IAppBuilder app,
+            BoxAuthenticationOptions options)
+            : base(next, options)
+        {
+            if (string.IsNullOrWhiteSpace(Options.ClientId))
+                throw new ArgumentException(string.Format(CultureInfo.CurrentCulture,
+                    Resources.Exception_OptionMustBeProvided, nameof(Options.ClientId)));
+            if (string.IsNullOrWhiteSpace(Options.ClientSecret))
+                throw new ArgumentException(string.Format(CultureInfo.CurrentCulture,
+                    Resources.Exception_OptionMustBeProvided, nameof(Options.ClientSecret)));
+
+            _logger = app.CreateLogger<BoxAuthenticationMiddleware>();
+
+            if (Options.Provider == null)
+                Options.Provider = new BoxAuthenticationProvider();
+
+            if (Options.StateDataFormat == null)
+            {
+                var dataProtector = app.CreateDataProtector(
+                    typeof (BoxAuthenticationMiddleware).FullName,
+                    Options.AuthenticationType, "v1");
+                Options.StateDataFormat = new PropertiesDataFormat(dataProtector);
+            }
+
+            if (string.IsNullOrEmpty(Options.SignInAsAuthenticationType))
+                Options.SignInAsAuthenticationType = app.GetDefaultSignInAsAuthenticationType();
+
+            _httpClient = new HttpClient(ResolveHttpMessageHandler(Options))
+            {
+                Timeout = Options.BackchannelTimeout,
+                MaxResponseContentBufferSize = 1024*1024*10
+            };
+        }
+
+        /// <summary>
+        ///     Provides the <see cref="T:Microsoft.Owin.Security.Infrastructure.AuthenticationHandler" /> object for processing
+        ///     authentication-related requests.
+        /// </summary>
+        /// <returns>
+        ///     An <see cref="T:Microsoft.Owin.Security.Infrastructure.AuthenticationHandler" /> configured with the
+        ///     <see cref="T:Owin.Security.Providers.Box.BoxAuthenticationOptions" /> supplied to the constructor.
+        /// </returns>
+        protected override AuthenticationHandler<BoxAuthenticationOptions> CreateHandler()
+        {
+            return new BoxAuthenticationHandler(_httpClient, _logger);
+        }
+
+        private static HttpMessageHandler ResolveHttpMessageHandler(BoxAuthenticationOptions options)
+        {
+            var handler = options.BackchannelHttpHandler ?? new WebRequestHandler();
+
+            // If they provided a validator, apply it or fail.
+            if (options.BackchannelCertificateValidator == null) return handler;
+            // Set the cert validate callback
+            var webRequestHandler = handler as WebRequestHandler;
+            if (webRequestHandler == null)
+            {
+                throw new InvalidOperationException(Resources.Exception_ValidatorHandlerMismatch);
+            }
+            webRequestHandler.ServerCertificateValidationCallback = options.BackchannelCertificateValidator.Validate;
+
+            return handler;
+        }
+    }
+}

src/Owin.Security.Providers.Box/BoxAuthenticationOptions.cs

@@ -0,0 +1,92 @@
+using System;
+using System.Net.Http;
+using Microsoft.Owin;
+using Microsoft.Owin.Security;
+
+namespace Owin.Security.Providers.Box
+{
+    public class BoxAuthenticationOptions : AuthenticationOptions
+    {
+        /// <summary>
+        ///     Gets or sets the a pinned certificate validator to use to validate the endpoints used
+        ///     in back channel communications belong to Box
+        /// </summary>
+        /// <value>
+        ///     The pinned certificate validator.
+        /// </value>
+        /// <remarks>
+        ///     If this property is null then the default certificate checks are performed,
+        ///     validating the subject name and if the signing chain is a trusted party.
+        /// </remarks>
+        public ICertificateValidator BackchannelCertificateValidator { get; set; }
+
+        /// <summary>
+        ///     The HttpMessageHandler used to communicate with Box.
+        ///     This cannot be set at the same time as BackchannelCertificateValidator unless the value
+        ///     can be downcast to a WebRequestHandler.
+        /// </summary>
+        public HttpMessageHandler BackchannelHttpHandler { get; set; }
+
+        /// <summary>
+        ///     Gets or sets timeout value in milliseconds for back channel communications with Box.
+        /// </summary>
+        /// <value>
+        ///     The back channel timeout in milliseconds.
+        /// </value>
+        public TimeSpan BackchannelTimeout { get; set; }
+
+        /// <summary>
+        ///     The request path within the application's base path where the user-agent will be returned.
+        ///     The middleware will process this request when it arrives.
+        ///     Default value is "/signin-box".
+        /// </summary>
+        public PathString CallbackPath { get; set; }
+
+        /// <summary>
+        ///     Get or sets the text that the user can display on a sign in user interface.
+        /// </summary>
+        public string Caption
+        {
+            get { return Description.Caption; }
+            set { Description.Caption = value; }
+        }
+
+        /// <summary>
+        ///     Gets or sets the Box supplied Client ID
+        /// </summary>
+        public string ClientId { get; set; }
+
+        /// <summary>
+        ///     Gets or sets the Box supplied Client Secret
+        /// </summary>
+        public string ClientSecret { get; set; }
+
+        /// <summary>
+        ///     Gets or sets the <see cref="IBoxAuthenticationProvider" /> used in the authentication events
+        /// </summary>
+        public IBoxAuthenticationProvider Provider { get; set; }
+
+        /// <summary>
+        ///     Gets or sets the name of another authentication middleware which will be responsible for actually issuing a user
+        ///     <see cref="System.Security.Claims.ClaimsIdentity" />.
+        /// </summary>
+        public string SignInAsAuthenticationType { get; set; }
+
+        /// <summary>
+        ///     Gets or sets the type used to secure data handled by the middleware.
+        /// </summary>
+        public ISecureDataFormat<AuthenticationProperties> StateDataFormat { get; set; }
+
+        /// <summary>
+        ///     Initializes a new <see cref="BoxAuthenticationOptions" />
+        /// </summary>
+        public BoxAuthenticationOptions()
+            : base("Box")
+        {
+            Caption = Constants.DefaultAuthenticationType;
+            CallbackPath = new PathString("/signin-box");
+            AuthenticationMode = AuthenticationMode.Passive;
+            BackchannelTimeout = TimeSpan.FromSeconds(60);
+        }
+    }
+}

src/Owin.Security.Providers.Box/Constants.cs

@@ -0,0 +1,7 @@
+namespace Owin.Security.Providers.Box
+{
+    internal static class Constants
+    {
+        public const string DefaultAuthenticationType = "Box";
+    }
+}

src/Owin.Security.Providers.Box/Owin.Security.Providers.Box.csproj

@@ -0,0 +1,102 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="14.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
+  <PropertyGroup>
+    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
+    <ProjectGuid>{1AEF8813-E1F9-41E1-BC8D-732960595E9F}</ProjectGuid>
+    <OutputType>Library</OutputType>
+    <AppDesignerFolder>Properties</AppDesignerFolder>
+    <RootNamespace>Owin.Security.Providers.Box</RootNamespace>
+    <AssemblyName>Owin.Security.Providers.Box</AssemblyName>
+    <TargetFrameworkVersion>v4.5</TargetFrameworkVersion>
+    <FileAlignment>512</FileAlignment>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>full</DebugType>
+    <Optimize>false</Optimize>
+    <OutputPath>bin\Debug\</OutputPath>
+    <DefineConstants>DEBUG;TRACE</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <OutputPath>bin\Release\</OutputPath>
+    <DefineConstants>TRACE</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+  </PropertyGroup>
+  <ItemGroup>
+    <Reference Include="Microsoft.Owin, Version=3.0.1.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\Microsoft.Owin.3.0.1\lib\net45\Microsoft.Owin.dll</HintPath>
+      <Private>True</Private>
+    </Reference>
+    <Reference Include="Microsoft.Owin.Security, Version=3.0.1.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\Microsoft.Owin.Security.3.0.1\lib\net45\Microsoft.Owin.Security.dll</HintPath>
+      <Private>True</Private>
+    </Reference>
+    <Reference Include="Newtonsoft.Json, Version=8.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\Newtonsoft.Json.8.0.3\lib\net45\Newtonsoft.Json.dll</HintPath>
+      <Private>True</Private>
+    </Reference>
+    <Reference Include="Owin, Version=1.0.0.0, Culture=neutral, PublicKeyToken=f0ebd12fd5e55cc5, processorArchitecture=MSIL">
+      <HintPath>..\..\packages\Owin.1.0\lib\net40\Owin.dll</HintPath>
+      <Private>True</Private>
+    </Reference>
+    <Reference Include="System" />
+    <Reference Include="System.Core" />
+    <Reference Include="System.Net.Http.WebRequest" />
+    <Reference Include="System.Xml.Linq" />
+    <Reference Include="System.Data.DataSetExtensions" />
+    <Reference Include="Microsoft.CSharp" />
+    <Reference Include="System.Data" />
+    <Reference Include="System.Net.Http" />
+    <Reference Include="System.Xml" />
+  </ItemGroup>
+  <ItemGroup>
+    <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="Constants.cs" />
+    <Compile Include="BoxAuthenticationExtensions.cs" />
+    <Compile Include="BoxAuthenticationHandler.cs" />
+    <Compile Include="BoxAuthenticationMiddleware.cs" />
+    <Compile Include="BoxAuthenticationOptions.cs" />
+    <Compile Include="Provider\BoxAuthenticatedContext.cs" />
+    <Compile Include="Provider\BoxAuthenticationProvider.cs" />
+    <Compile Include="Provider\BoxReturnEndpointContext.cs" />
+    <Compile Include="Provider\IBoxAuthenticationProvider.cs" />
+    <Compile Include="Resources.Designer.cs">
+      <DependentUpon>Resources.resx</DependentUpon>
+      <AutoGen>True</AutoGen>
+      <DesignTime>True</DesignTime>
+    </Compile>
+  </ItemGroup>
+  <ItemGroup>
+    <EmbeddedResource Include="Resources.resx">
+      <Generator>ResXFileCodeGenerator</Generator>
+      <LastGenOutput>Resources.Designer.cs</LastGenOutput>
+    </EmbeddedResource>
+  </ItemGroup>
+  <ItemGroup>
+    <None Include="packages.config" />
+  </ItemGroup>
+  <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
+  <Target Name="PostBuildMacros">
+    <GetAssemblyIdentity AssemblyFiles="$(TargetPath)">
+      <Output TaskParameter="Assemblies" ItemName="Targets" />
+    </GetAssemblyIdentity>
+    <ItemGroup>
+      <VersionNumber Include="@(Targets->'%(Version)')" />
+    </ItemGroup>
+  </Target>
+  <PropertyGroup>
+    <PreBuildEvent>
+    </PreBuildEvent>
+    <PostBuildEventDependsOn>
+      $(PostBuildEventDependsOn);
+      PostBuildMacros;
+    </PostBuildEventDependsOn>
+  </PropertyGroup>
+</Project>

src/Owin.Security.Providers.Box/Properties/AssemblyInfo.cs

@@ -0,0 +1,15 @@
+using System.Reflection;
+using System.Runtime.InteropServices;
+
+[assembly: AssemblyTitle("Owin.Security.Providers.Box")]
+[assembly: AssemblyDescription("")]
+[assembly: AssemblyConfiguration("")]
+[assembly: AssemblyCompany("")]
+[assembly: AssemblyProduct("Owin.Security.Providers.Box")]
+[assembly: AssemblyCopyright("Copyright ©  2016")]
+[assembly: AssemblyTrademark("")]
+[assembly: AssemblyCulture("")]
+[assembly: ComVisible(false)]
+[assembly: Guid("1242F9A5-AEF8-44F8-A255-F0D24DAE0A2C")]
+[assembly: AssemblyVersion("2.0.0.0")]
+[assembly: AssemblyFileVersion("2.0.0.0")]

src/Owin.Security.Providers.Box/Provider/BoxAuthenticatedContext.cs

@@ -0,0 +1,77 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.txt in the project root for license information.
+
+using System.Security.Claims;
+using Microsoft.Owin;
+using Microsoft.Owin.Security;
+using Microsoft.Owin.Security.Provider;
+using Newtonsoft.Json.Linq;
+
+namespace Owin.Security.Providers.Box
+{
+    /// <summary>
+    /// Contains information about the login session as well as the user <see cref="System.Security.Claims.ClaimsIdentity"/>.
+    /// </summary>
+    public class BoxAuthenticatedContext : BaseContext
+    {
+        /// <summary>
+        /// Initializes a <see cref="BoxAuthenticatedContext"/>
+        /// </summary>
+        /// <param name="context">The OWIN environment</param>
+        /// <param name="user">The JSON-serialized user</param>
+        /// <param name="accessToken">Box Access token</param>
+        public BoxAuthenticatedContext(IOwinContext context, JObject user, string accessToken)
+            : base(context)
+        {
+            AccessToken = accessToken;
+            User = user;
+
+            Id = TryGetValue(user, "id");
+            Name = TryGetValue(user, "name");
+            Login = TryGetValue(user, "login");
+        }
+
+        /// <summary>
+        /// Gets the JSON-serialized user
+        /// </summary>
+        /// <remarks>
+        /// Contains the Box user obtained from the endpoint https://api.box.com/2.0/users/me
+        /// </remarks>
+        public JObject User { get; private set; }
+
+        /// <summary>
+        /// Gets the Box OAuth access token
+        /// </summary>
+        public string AccessToken { get; private set; }
+
+        /// <summary>
+        /// Gets the Box user ID
+        /// </summary>
+        public string Id { get; private set; }
+
+        /// <summary>
+        /// The name of the user
+        /// </summary>
+        public string Name { get; private set; }
+
+        /// <summary>
+        /// The login of the user
+        /// </summary>
+        public string Login { get; private set; }
+
+        /// <summary>
+        /// Gets the <see cref="ClaimsIdentity"/> representing the user
+        /// </summary>
+        public ClaimsIdentity Identity { get; set; }
+
+        /// <summary>
+        /// Gets or sets a property bag for common authentication properties
+        /// </summary>
+        public AuthenticationProperties Properties { get; set; }
+
+        private static string TryGetValue(JObject user, string propertyName)
+        {
+            JToken value;
+            return user.TryGetValue(propertyName, out value) ? value.ToString() : null;
+        }
+    }
+}

src/Owin.Security.Providers.Box/Provider/BoxAuthenticationProvider.cs

@@ -0,0 +1,50 @@
+using System;
+using System.Threading.Tasks;
+
+namespace Owin.Security.Providers.Box
+{
+    /// <summary>
+    /// Default <see cref="IBoxAuthenticationProvider"/> implementation.
+    /// </summary>
+    public class BoxAuthenticationProvider : IBoxAuthenticationProvider
+    {
+        /// <summary>
+        /// Initializes a <see cref="BoxAuthenticationProvider"/>
+        /// </summary>
+        public BoxAuthenticationProvider()
+        {
+            OnAuthenticated = context => Task.FromResult<object>(null);
+            OnReturnEndpoint = context => Task.FromResult<object>(null);
+        }
+
+        /// <summary>
+        /// Gets or sets the function that is invoked when the Authenticated method is invoked.
+        /// </summary>
+        public Func<BoxAuthenticatedContext, Task> OnAuthenticated { get; set; }
+
+        /// <summary>
+        /// Gets or sets the function that is invoked when the ReturnEndpoint method is invoked.
+        /// </summary>
+        public Func<BoxReturnEndpointContext, Task> OnReturnEndpoint { get; set; }
+
+        /// <summary>
+        /// Invoked whenever Box successfully authenticates a user
+        /// </summary>
+        /// <param name="context">Contains information about the login session as well as the user <see cref="System.Security.Claims.ClaimsIdentity"/>.</param>
+        /// <returns>A <see cref="Task"/> representing the completed operation.</returns>
+        public virtual Task Authenticated(BoxAuthenticatedContext context)
+        {
+            return OnAuthenticated(context);
+        }
+
+        /// <summary>
+        /// Invoked prior to the <see cref="System.Security.Claims.ClaimsIdentity"/> being saved in a local cookie and the browser being redirected to the originally requested URL.
+        /// </summary>
+        /// <param name="context"></param>
+        /// <returns>A <see cref="Task"/> representing the completed operation.</returns>
+        public virtual Task ReturnEndpoint(BoxReturnEndpointContext context)
+        {
+            return OnReturnEndpoint(context);
+        }
+    }
+}

src/Owin.Security.Providers.Box/Provider/BoxReturnEndpointContext.cs

@@ -0,0 +1,26 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.txt in the project root for license information.
+
+using Microsoft.Owin;
+using Microsoft.Owin.Security;
+using Microsoft.Owin.Security.Provider;
+
+namespace Owin.Security.Providers.Box
+{
+    /// <summary>
+    /// Provides context information to middleware providers.
+    /// </summary>
+    public class BoxReturnEndpointContext : ReturnEndpointContext
+    {
+        /// <summary>
+        /// 
+        /// </summary>
+        /// <param name="context">OWIN environment</param>
+        /// <param name="ticket">The authentication ticket</param>
+        public BoxReturnEndpointContext(
+            IOwinContext context,
+            AuthenticationTicket ticket)
+            : base(context, ticket)
+        {
+        }
+    }
+}

src/Owin.Security.Providers.Box/Provider/IBoxAuthenticationProvider.cs

@@ -0,0 +1,24 @@
+using System.Threading.Tasks;
+
+namespace Owin.Security.Providers.Box
+{
+    /// <summary>
+    /// Specifies callback methods which the <see cref="BoxAuthenticationMiddleware"></see> invokes to enable developer control over the authentication process. />
+    /// </summary>
+    public interface IBoxAuthenticationProvider
+    {
+        /// <summary>
+        /// Invoked whenever Box successfully authenticates a user
+        /// </summary>
+        /// <param name="context">Contains information about the login session as well as the user <see cref="System.Security.Claims.ClaimsIdentity"/>.</param>
+        /// <returns>A <see cref="Task"/> representing the completed operation.</returns>
+        Task Authenticated(BoxAuthenticatedContext context);
+
+        /// <summary>
+        /// Invoked prior to the <see cref="System.Security.Claims.ClaimsIdentity"/> being saved in a local cookie and the browser being redirected to the originally requested URL.
+        /// </summary>
+        /// <param name="context"></param>
+        /// <returns>A <see cref="Task"/> representing the completed operation.</returns>
+        Task ReturnEndpoint(BoxReturnEndpointContext context);
+    }
+}

src/Owin.Security.Providers.Box/Resources.Designer.cs

@@ -0,0 +1,81 @@
+//------------------------------------------------------------------------------
+// <auto-generated>
+//     This code was generated by a tool.
+//     Runtime Version:4.0.30319.42000
+//
+//     Changes to this file may cause incorrect behavior and will be lost if
+//     the code is regenerated.
+// </auto-generated>
+//------------------------------------------------------------------------------
+
+namespace Owin.Security.Providers.Box {
+    using System;
+    
+    
+    /// <summary>
+    ///   A strongly-typed resource class, for looking up localized strings, etc.
+    /// </summary>
+    // This class was auto-generated by the StronglyTypedResourceBuilder
+    // class via a tool like ResGen or Visual Studio.
+    // To add or remove a member, edit your .ResX file then rerun ResGen
+    // with the /str option, or rebuild your VS project.
+    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("System.Resources.Tools.StronglyTypedResourceBuilder", "4.0.0.0")]
+    [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]
+    [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]
+    internal class Resources {
+        
+        private static global::System.Resources.ResourceManager resourceMan;
+        
+        private static global::System.Globalization.CultureInfo resourceCulture;
+        
+        [global::System.Diagnostics.CodeAnalysis.SuppressMessageAttribute("Microsoft.Performance", "CA1811:AvoidUncalledPrivateCode")]
+        internal Resources() {
+        }
+        
+        /// <summary>
+        ///   Returns the cached ResourceManager instance used by this class.
+        /// </summary>
+        [global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Advanced)]
+        internal static global::System.Resources.ResourceManager ResourceManager {
+            get {
+                if (object.ReferenceEquals(resourceMan, null)) {
+                    global::System.Resources.ResourceManager temp = new global::System.Resources.ResourceManager("Owin.Security.Providers.Box.Resources", typeof(Resources).Assembly);
+                    resourceMan = temp;
+                }
+                return resourceMan;
+            }
+        }
+        
+        /// <summary>
+        ///   Overrides the current thread's CurrentUICulture property for all
+        ///   resource lookups using this strongly typed resource class.
+        /// </summary>
+        [global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Advanced)]
+        internal static global::System.Globalization.CultureInfo Culture {
+            get {
+                return resourceCulture;
+            }
+            set {
+                resourceCulture = value;
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to The &apos;{0}&apos; option must be provided..
+        /// </summary>
+        internal static string Exception_OptionMustBeProvided {
+            get {
+                return ResourceManager.GetString("Exception_OptionMustBeProvided", resourceCulture);
+            }
+        }
+        
+        /// <summary>
+        ///   Looks up a localized string similar to An ICertificateValidator cannot be specified at the same time as an HttpMessageHandler unless it is a WebRequestHandler..
+        /// </summary>
+        internal static string Exception_ValidatorHandlerMismatch {
+            get {
+                return ResourceManager.GetString("Exception_ValidatorHandlerMismatch", resourceCulture);
+            }
+        }
+    }
+}

src/Owin.Security.Providers.Box/Resources.resx

@@ -0,0 +1,126 @@
+<?xml version="1.0" encoding="utf-8"?>
+<root>
+  <!-- 
+    Microsoft ResX Schema 
+    
+    Version 2.0
+    
+    The primary goals of this format is to allow a simple XML format 
+    that is mostly human readable. The generation and parsing of the 
+    various data types are done through the TypeConverter classes 
+    associated with the data types.
+    
+    Example:
+    
+    ... ado.net/XML headers & schema ...
+    <resheader name="resmimetype">text/microsoft-resx</resheader>
+    <resheader name="version">2.0</resheader>
+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
+    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>
+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
+        <value>[base64 mime encoded serialized .NET Framework object]</value>
+    </data>
+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
+        <comment>This is a comment</comment>
+    </data>
+                
+    There are any number of "resheader" rows that contain simple 
+    name/value pairs.
+    
+    Each data row contains a name, and value. The row also contains a 
+    type or mimetype. Type corresponds to a .NET class that support 
+    text/value conversion through the TypeConverter architecture. 
+    Classes that don't support this are serialized and stored with the 
+    mimetype set.
+    
+    The mimetype is used for serialized objects, and tells the 
+    ResXResourceReader how to depersist the object. This is currently not 
+    extensible. For a given mimetype the value must be set accordingly:
+    
+    Note - application/x-microsoft.net.object.binary.base64 is the format 
+    that the ResXResourceWriter will generate, however the reader can 
+    read any of the formats listed below.
+    
+    mimetype: application/x-microsoft.net.object.binary.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
+            : and then encoded with base64 encoding.
+    
+    mimetype: application/x-microsoft.net.object.soap.base64
+    value   : The object must be serialized with 
+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
+            : and then encoded with base64 encoding.
+
+    mimetype: application/x-microsoft.net.object.bytearray.base64
+    value   : The object must be serialized into a byte array 
+            : using a System.ComponentModel.TypeConverter
+            : and then encoded with base64 encoding.
+    -->
+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
+    <xsd:element name="root" msdata:IsDataSet="true">
+      <xsd:complexType>
+        <xsd:choice maxOccurs="unbounded">
+          <xsd:element name="metadata">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" />
+              </xsd:sequence>
+              <xsd:attribute name="name" use="required" type="xsd:string" />
+              <xsd:attribute name="type" type="xsd:string" />
+              <xsd:attribute name="mimetype" type="xsd:string" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="assembly">
+            <xsd:complexType>
+              <xsd:attribute name="alias" type="xsd:string" />
+              <xsd:attribute name="name" type="xsd:string" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="data">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />
+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />
+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />
+              <xsd:attribute ref="xml:space" />
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="resheader">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
+              </xsd:sequence>
+              <xsd:attribute name="name" type="xsd:string" use="required" />
+            </xsd:complexType>
+          </xsd:element>
+        </xsd:choice>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:schema>
+  <resheader name="resmimetype">
+    <value>text/microsoft-resx</value>
+  </resheader>
+  <resheader name="version">
+    <value>2.0</value>
+  </resheader>
+  <resheader name="reader">
+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <resheader name="writer">
+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
+  </resheader>
+  <data name="Exception_OptionMustBeProvided" xml:space="preserve">
+    <value>The '{0}' option must be provided.</value>
+  </data>
+  <data name="Exception_ValidatorHandlerMismatch" xml:space="preserve">
+    <value>An ICertificateValidator cannot be specified at the same time as an HttpMessageHandler unless it is a WebRequestHandler.</value>
+  </data>
+</root>

src/Owin.Security.Providers.Box/packages.config

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="Microsoft.Owin" version="3.0.1" targetFramework="net45" />
+  <package id="Microsoft.Owin.Security" version="3.0.1" targetFramework="net45" />
+  <package id="Newtonsoft.Json" version="8.0.3" targetFramework="net45" />
+  <package id="Owin" version="1.0" targetFramework="net45" />
+</packages>