I have two Azure AD applications in the same directory, let’s call them FrontendAuth and BackendAuth, which provide authentication for an ASP.NET MVC frontend and a Web API backend, respectively. The MVC frontend is protected using the standard UseOpenIdConnectAuthentication configuration, the Web API backend with UseWindowsAzureActiveDirectoryBearerAuthentication.
What I want to do is log into the frontend, authenticate against FrontendAuth, then consume via JavaScript the API hosted in the backend by providing a token, acquired using ADAL JS, to BackendAuth.
Assumptions
My expectations/assumptions are:
That I would have to configure FrontendAuth to have access to BackendAuth in the classic portal
That I would have to edit the manifest files of one or both of these to set oauth2AllowImplicitFlow to true
That when I configure ADAL JS I should be setting clientId to be that of FrontendAuth
The endpoints object of the ADAL JS configuration should contain the Url of the backend API and the client ID of BackendAuth
Outcome
I can achieve my goal of logging in to the frontend and communicating with the backend service via ADAL JS with:
The FrontendAuth application having no access to BackendAuth at all
Neither manifest file having the oauth2AllowImplicitFlow property set to true
ADAL JS having the clientId set to be that of BackendAuth
The endpoints object of the ADAL JS configuration not set at all
Questions
Based on these findings I would like to understand the following:
Were my assumptions correct? Is this how ADAL JS is intended to work?
Why did the lack of application access and unchanged manifest files have no effect on whether the authentication succeeded?
When do these measures have an effect on the authentication outcome?
You are mixing up two OAuth2 flows here (authorization code flow and implicit flow). Both are meant to issue a token to a client application. The auth code flow is used for web apps running on the server (like your MVC app) and the implicit flow is meant for public clients like a SPA.
When you use OpenID Connect to sign in your user to your MVC application, using the hybrid flow, you receive an authorization code from the browser. You use this code to talk to the authorization server and get a JWT token which is then stored in a cookie session. You can use the same code to get a JWT token for your BackendAuth app, as long as you have given permission to your FrontendAuth app to call the BackendAuth app.
If you want to enable the JavaScript in the user's browser to call into the BackendAuth app, you'll need to somehow pass the access token to the browser. You can do this by sending the token along with the initial request and put it in local storage or expose a (secured) MVC route to get the token.
For an example of what I'm describing here see this Azure AD sample, which acquires a token for the Graph API using the authorization code is received.
ADAL.js implements the implicit flow and is meant for JavaScript applications like SPAs etc.
It sounds like you haven't explicitly decorated your Web API controllers with [Authorize] attributes (either at the class level, or the action level). Thus, your Web API may be happy to serve content to anyone who requests it.
Related
I am building a web app with the following properties:
The Front-end is based on VueJS
The Back-end framework is still not confirmed but it will be a RESTFul API
The users for the app will be authenticated by Azure Active Directory (AAD)
Here's what I have done so far:
I have set up a Web App/API in my AAD. Along with that following the guidelines here, I have completely secured my VueJS app and now I need to be logged in into my AAD in order to be able to use the app.
The problem now is that, the front-end is secured. But what about the backend? I am trying to get an access_token from the AAD which I can then use as an authorization header with every request to my backend later on.
Here is what I get from my AAD when I sign in using the AuthenticationContext from the adal library.
As you can see I am getting an id_token and when I use the acquireToken function of adal I get an id_token again.
Is there anything I am doing wrong here? Do I need to create another Web App/API on Azure?
How do I go about this?
Thanks!
According to official documentation and this might be your case.
"The OAuth 2.0 implicit flow in Azure AD is designed to return an ID token when the resource for which the token is being requested is the same as the client application. In other words, when the JS client uses ADAL JS to request a token for its own backend web API registered with same App ID as the client, an ID token is returned and cached by the library. Note that in this case the resource should be set to the App ID of the client (App ID URI will not work). This ID token can then be used as a bearer token in the calls to your application's backend API."
You can find more about this here!
https://github.com/AzureAD/azure-activedirectory-library-for-js/wiki/Acquire-tokens
For a while now I had a .Net WPF application that uses Adal.Net to perform (what i believe is) an Authorization code grant flow against azure active directory to access a web API (which is looking for a bearer token in the request).
For this purpose I'm using 2 AAD applications: MyServer (which represents the server) and MyClient (which represents the WPF client). In the azure portal I configued Myclient with permission to access MyServer.
When calling AcquireToken from my WPF application i'm supplying MyClient.ClientId as the client ID and MyServer.ResourceUrl as the resource id, and everything works as expected.
Now I have a website (that only serves static pages using IIS - it does not have asp.net nor node.js as web servers).
I would like to my browser to perform the same flow the .Net native app performed.
I've looked at adal.js but wasn't able to find an easy way to do it.
Must I implement the entire flow by hand?
Rony, AAD doesn't support cross origin calls on the token endpoint - so you won't be able to implement the auth code grant OAuth flow in JS (the token request using the code will fail). AAD supports the implicit grant OAuth flow for the scenario you describe (single page app calling a web api).
ADAL.js implements the implicit grant flow. Please let us know if you have any issues using it.
Hope that helps.
I'm trying to use Doorkeeper in a Ruby on Rails API app for authentication. From a client-side AngularJS app, I want to get an access token. Currently, this involves a GET request to /oauth/authorize, which gives me a code, then I POST that code along with a client_id and a secret to /oauth/token. I don't want to have to send the client ID and secret from my client-side app, since they're stored in plain-text in a JavaScript file. I would like to follow this flow where response_type is token, not code, but I can't figure out how to do that with Doorkeeper. Their wiki examples all seem to involve POSTing the client ID and secret to /oauth/token.
Is Doorkeeper the right gem for this? How can I do Google OAuth2 from a client-side app, where no secrets are passed from client-side to the server?
Edit: looks like what I want is Implicit Grant, which Doorkeeper supports. Now I just have to find out how to do that in my Rails app...
No extra server-side configuration necessary.
When I created a new Doorkeeper::Application in my Rails app, the Doorkeeper interface gave me an Authorize link with response_type=code in it for that application.
I changed that to response_type=token and when I do a GET request to that, it responds immediately with access_token instead of code. The Authorize URL looks like http://my-rails-doorkeeper-app/oauth/authorize?client_id=1234&redirect_uri=http://my-angularjs-app&response_type=token.
Update :
This can only be applied when we also allow implicit grant for the grant flow.
By default, doorkeeper will allow its four kinds of flow (implicit grant, authorization grant, password, and client_credentials).
You can configure it in initializer/doorkeeper.rb if you don't want to let it happens since sometimes it can be dangerous.
The Problem:
Serving a secure API to a client side app using only a local authentication strategy. The red arrows are part of the knowledge gap.
Context:
That is --- client.example.com is making a POST to api.example.com/login where on success client.example.com can gain access to a GET service like api.example.com/secret.
An idea!
Implimentation of OAuth 2.0 with hybrid grant type sitting in front of API.
Why hybrid?
It wouldn't be an Implicit Grant Flow aka Client-Side Web Applications Flow because there is no redirection to API server too grant access token. (i.e.) "Is it ok for so-and-so to access your data?"
It wouldn't be a Resource Owner Password Flow because a Client ID and Client Secret are passed along with the request so it's assumed the client app is server-side.
OK... so what about a little bit of both?
What if we used a CRSF token on page load of client-side app, and POST it with user credentials too OAuth 2.0 authentication endpoint to exchange for access token? You would authenticate each subsequent request with the access token and CRSF token after a successful login.
A good Node.js OAuth 2.0 library I found:
https://github.com/ammmir/node-oauth2-provider
Help Me!
I can not find a working example of an authentication measure that solves this problem! Point me in the right direction?
Ultimately, the goal here is too authenticate a client side app to a REST api using CORS with a local strategy --- i.e. username & password --- even if the convention above isn't possible.
To Accommodate Bounty:
This is a client side app, so let's stay trendy.
I'm looking for a working example using the Node.js OAuth 2.0 seed above for the API/Auth server and a front end framework like Angular.js or Backbone.js to make requests.
The example should match the context described above.
I'm working on an app with a pretty similar architecture though the services are .NET Web API rather than Node and we're using DotNetOpenAuth for the OAuth provider. Rather than the hybrid approach you're suggesting we're doing the following:
x.com serves up a login page
login page POSTs back credentials to x.com
server side logic at x.com combines client_id and client_secret with the credentials to submit a token request (resource owner password credentials grant that you've
mentioned above) receiving back both a temporary access token and a
refresh token
the refresh token is encrypted into a cookie issued by x.com
both the cookie (with encrypted refresh token) and the temporary access token are then sent to the browser
the client app (angular in my case) can now use the access token to hit api.x.com for services (It appears you're well aware of the limitations of CORS... we hacked a version of angular's $resource to facilitate this but it wasn't pretty since we wanted to use all HTTP verbs and support IE9)
when the access token expires, the client side app can request a new access token from x.com
server-side, x.com decrypts the cookie to get at the refresh token and issues another oauth call for a new access token
This is fairly high-level but hopefully gives you a sense for how to tackle your situation. In my case, and it appears in yours, we didn't want to use session state or a database to store the refresh token but obviously exposing that to the browser introduces security concerns so the encryption of the refresh token is important (among other security considerations) and the use of the cookie eliminates the need for session state or other persistent storage on x.com.
Not an answer running for the prize. Just my 2 cents :)
On my web server,
I do my authentication through a rest call with login/password with basic authentication over https. This call delivers a key to the client (a one page web app).
Then every subsequent REST call is signed with the key. The server checks that the signature is correct and everything still happen in https.
This mechanism is quite used I believe.
I don't see the issue with cross domain. I have a single source anf if I need something from another source, I'd use JSONP.
I use nginx as an https->http forwarder.
Not sure how it competes with an OAuth2 solution.
I've built this example using Node and PassportJS to show how to authenticate the users with Facebook or Local Strategy. Both sides are on different domains as you described and it requires CORS enabled.
GitHub: https://github.com/pablodenadai/Corsnection
Live demo: http://corsnection-client.herokuapp.com/
I can't promise that I have time to write working example but I can show you 2 paths :)
The biggest deal is CORS. After you solve that problem it is easy to use $http service. So, first and probably easiest may be to configure reverse proxy in x.com webserver which points to api.x.com. I wrote article here
Second approach is better, and created for exactly this purpose, to authorise specific domain to use your resource. It involves a bit of coding in api.x.com so you don't have to change anything in new web applications served in other domains. You simply need to authorise CORS requests in api.x.com service.
Create table in database where you can manage list of authorised domains
Add in that table record "x.com"
in api.x.com add request filter/interceptor what ever tech term you use for method which should be invoked after request is handled and add in response Access-Control-Allow-Origin: x.com if request comes from x.com (in other words check in request header refer value match to any value in table above and put that value in Access-Control-Allow-Origin response header).
That is all :) After this if you know how to use $http or jQuey.ajax you will be able to POST/PUT/DELETE/... any request to api.x.com from any authorised domain in just few minutes.
I very similar idea using vinilla js web app and cross domain authentication to GAE backend or OpenID connect.
The web app is run on CDN. When click login link, it goes to respective login server and redirect back to the web app (with XSRF security token and HTTPS only cookie). Login server accept cross domain request with credentials. XSRF token has to be set (in header) with every request. cookie is set by the browser. Since it is HTTP only cookie, JS cannot read it. The technique is very secure.
Once login, you can get secure assess from login server.
For detail description, you can find here and open source repo here.
I am building an API and had questions about handling authentication when using a front-end framework such as Backbone.js.
I have a single API server that is responsible for returning and modifying data based on RESTful web requests.
I have another app server that is a Backbone application. I want this application to connect directly with my API server, so set the entire project up so that this app server can make cross-domain AJAX requests to the API server.
There are some API routes that I do not want unauthorized parties to obtain access to. For example, I have a path /users that lists all the users of my app. I need this path later on for admin functions, but I don't want it publicly available to my app server.
What is a good authentication scheme to use? OAuth won't work because the secret token would be exposed on the front-end. And after that, I'm a little stuck with what my options are. Does anyone have any suggestions moving forward?
In cases like these I use a combination of techniques.
-- Good ole Cookie based auth
As a backbone app will always be used inside a browser and browsers have built-in cookie support, I would suggest that you should accept cookie based sessions on the server side. All the auth related stuff will be handled by the browser and you don't have to worry about storing keys etc. On top many libraries like (NSURL in iPhone) and frameworks (like PhoneGap/Trigger) all support cookies so woha you can support all kind of clients with litte work.
-- Plain API Key
For third-parties, I use api-key based authentication. You provide username and password, I provide key. You send me that key every time in HTTP header for all subsequent requests. I use the key to identify you and then allow/disallow actions accordingly.
I assume once you can authenticate a user (wait..who are you?), then you can setup authorizations ( you say Micheal ? ...ok you can access /users )
Also take a look at my backbone-parse plugin for an idea on how to authenticate users against an external API service #shamelessplug