using System;

using System.Net;

using System.Security.Cryptography;

using System.Security.Cryptography.X509Certificates;

using System.Security.Principal;

using System.ServiceModel.Channels;

using System.Threading;

using System.Web.Http;

using System.Web.Http.Controllers;

using System.Web.Http.Filters;

using DotNetOpenAuth.OAuth2;

 

namespace ProjectName.Web.Controllers.ActionFilters

{

/// <summary>

/// ActionFilter to authorize requests using OAuth2

/// </summary>

public class OAuth2Authorize : AuthorizationFilterAttribute

{

/// <summary>

/// Called when [authorization].

/// </summary>

public override void OnAuthorization(HttpActionContext actionContext)

{

// get public / private key from certificate

var store = new X509Store(StoreLocation.LocalMachine);

store.Open(OpenFlags.ReadOnly);

var certCollection = store.Certificates;

var currentCerts = certCollection.Find(X509FindType.FindByTimeValid, DateTime.Now, false);

var signingCert = currentCerts.Find(X509FindType.FindBySubjectDistinguishedName, "CN=*.yourdomain.com, OU=Domain Control Validated, O=*.yourdomain.com", false);

var cert = signingCert[0];

store.Close();

 

var publicKey = (RSACryptoServiceProvider)cert.PublicKey.Key;

var privateKey = (RSACryptoServiceProvider)cert.PrivateKey;

 

using (var signing = publicKey)

using (var encrypting = privateKey)

{

base.OnAuthorization(actionContext);

 

// TODO FIXME dnoa doesn't support HttpRequestMessage - manually creating HttpRequestMessageProperty until they do

var request = new HttpRequestMessageProperty();

request.Headers[HttpRequestHeader.Authorization] = actionContext.Request.Headers.Authorization.ToString();

var requestUri = actionContext.Request.RequestUri;

 

var resourceServer = new ResourceServer(new StandardAccessTokenAnalyzer(signing, encrypting));

IPrincipal result;

 

var response = resourceServer.VerifyAccess(request, requestUri, out result);

 

if (response != null)

{

actionContext.Response = actionContext.ControllerContext.Request.CreateResponse(HttpStatusCode.Forbidden);

return;

}

 

var principal = null; // create your principal using result.Identity.Name if needed

Thread.CurrentPrincipal = principal;

}

}

}

}