Azure AD authorization directly from mobile app - azure

I'm working on Xamarin.Forms application where user should Authorize using Azure AD B2C. I've managed it just fine using this library.
Now I'd like to know if it is possible to authorize without redirecting to webview. When user enters email and password on app send a get request directly to an url and receive access token, refresh token and etc. Just like in OAuth 2.0.
I've researched and found out that skipping the webview authentication part is doable but extremely not recommended for security reasons but anyway, would be glad to hear any solutions.

Webview runs on SSL (https) and hence transmission of user credentials for authentication is secured.
It’s worth noting that you don’t have to use a web view for authentication; you may create your own user interface for this flow and pass the information back to MSAL.
- this is mentioned on the same blog-post which you referred to.
All you have to do is to design your own interface and pass back the login info. It seems like a little work to do.

Related

Azure AD: Can I use an Authorization Code token to request an access token from a web service?

So, this is kind of related to the question here: How to enable CORS in an Azure App Registration when used in an OAuth Authorization Flow with PKCE?
I want to implement OAuth 2 for our single page JavaScript applications written in ExtJS.
The server-side is written in .NET (4.6.2 currently) and has both JSON services used by the UI (implementing Ext.Direct) and SOAP services used for client integration.
We currently handle our own authentication which works quite similarly to the authorization code flow really. We login with a client id, username and password to get a token generation token (TGT), and then use this to request a short-lived product service token (PST). Requesting a PST extends the life of the TGT. When the TGT expires the user has to re-authenticate.
For the OAuth 2 route I obviously would like the user interface to direct people at the login page for Azure, the user to login there, with whatever MFA they may require, and then come back to the UI as a known user.
I'm not bothered where I go for the product service token, although I think it makes sense to go to Azure if possible, since ultimately we'd like to move everyone in that direction I suspect.
So, I have wrapped some of the code above in an ExtJS class, and managed to retrieve a valid authorization token. So far so good.
When I then attempt to request an access token I hit the same issue with CORS that the poster of that question did.
I just cannot see how anyone can be using the Authorization Code with PKCE flow with Azure at the moment, since your application will never be hosted on the same domain used for login surely?!
Anyway. I'm wondering about my options.
I'm wondering now if I can post the authorization code that gets passed back to the UI (with the PKCE code perhaps) up to the web services and get the web services to handle the communication with Azure for the access tokens.
Does that stand more chance of success, or am I just going to hit the same problem there?
Implicit Flow is not an option. None of our clients will accept that.
What other options are there?
Is there a purely server-side to Azure option that I should be using, and worry about the UI afterwards?
Struggling to see a way forward!
Would appreciate any insights you may have.
Cheers,
Westy
Okay, after days of banging my head against the stupidity of Azure's implementation I stumbled upon a little hidden nugget of information here: https://github.com/AzureAD/microsoft-authentication-library-for-js/tree/dev/lib/msal-browser#prerequisites
If you change the type of the redirectUri in the manifest from 'Web' to 'Spa' it gives me back an access token! We're in business!
It breaks the UI in Azure, but so be it.
I hope this helps someone else going through similar pain.
I'll also post on the linked thread :)

Login App with IdentityServer4

I have to develop a SSO system and I have to do it using IdentityServer4. I have gone through the documentation and examples but I have some doubts. To be honest I don't quite get it, but I am really new in Oauth2 and OpenId Connect.
We will have a bunch of clients (web apps), each of one of those will have their own Web APi. And we have to have a centraliced Login App for all of those. I think the example with the javascript client is the closes to the thing we want to achieve. Also, a user might have permission to access one client (app), but not another, so the IdentityServer must provide information about wich clients (apps), that particularly user can access.
So, These are the things I don Understand:
1.- In the documentation I can read there are two tokens, an Identity Token and Access token. But in the examples all I see are the access tokens. It seems to me that the access token is the one with all de info needed. am I wrong?
2.- Also, I have read about de Grant Types and I'am not quite sure wich one we must use. At first I thought to use the ResourceOwner password, because it requires the client, the secret, a user and a password, wich I assumed it could be the end user. I found this example http://sunilrav.com/post/How-to-Customize-Authentication-in-Identity-Server-4 were one could customise the class that validate the user and password. I thought that this could be the way to go but the documentation statesa about this grant type "...This is so called “non-interactive” authentication and is generally not recommended.". The javascript client example uses the implicit Grat type, wich the documentation states is for browser-based applications (our client apps will all be browser based using react).
3.- can my Login app be a Javascript (react) app? The example Quickstart is made in MVC.NET. This login app connects directly to de IS4 server without asking for a access token? (In the example the app is embebed in the IS4).
4.- Can I protect with IS4 a WEB API which is developed in .net framework (4.6.2) and not in .Net Core? I havent Found Any examples.
the documentatios I followed is the offcial. The examples (quickstart) are also there. (I can't post more than two links).
thank you very much for reading and for your help.
Identity Token and Access token
Identity token is the one that contains the identity of the user, that will tell the client app that what user it is. After successful login, user will be redirected to the client app with these tokens. Response will also have claims, such as permission scopes, name , email you can add custom claims as well.
Access token is used to access your protected web api resource. You have to send the access token with each request to access the api.
Grant Types
Grant types is basically how you want your client app to interact with the auth server. https://identityserver4.readthedocs.io/en/release/topics/grant_types.html
can my Login app be a Javascript (react) app? Your client app can be a javascript app but your auth server that is the identity server which will have the login/signup pages(and other login jazz) and account controllers should be you MVC app. As, everything is already done using MVC and Entity framework, why you want to re do everything.
Can I protect with IS4 a WEB API I am not sure about this one, but I dont see why you would not be able to do it.
This is a good answer for basic IdSrv flow!
UPDATE In my understanding, the answer to which Grant Type to use it depends on your client application requirement. If you want to use a Javascript client you can use Implicit Flow, but you won't be able to use refresh tokens and your access token is not 100% secured with the browser as client can access it.
If you want to open your web api to public then you can use client credentials flow. If you want to be more secure you should use Hybrid flow or HybridClient credential flow. ( again depends on the requirements ). with this you will be able to use refresh tokens and in this way your access token would be more secure.

Is it possible to anonymously call API App and it automatically redirect the browser to AD Login page?

During the recent Microsoft Cloud roadshow in London, something that came out of one of the talks on App Service was using AAD B2C for authentication.
It is possible currently to add Azure AD as an authentication for an API App:
Calling this API app from a browser based web app with no authorization header results in a 302 redirect immediately followed by a 401 response.
It was mentioned at the cloud event that it would be possible to call an API app anonymously from a web app, and have the azure App service handle the redirection to the AAD login page, get the token on successful login and then pass the call on to the API app and return the data.
However, I am struggling to see how this can be achieved without any responsibility on the calling web app to handle the redirect. Normally you would handle a 401 response from an API by obtaining a bearer token via AAD on the client side and sending it through as the authorisation header with the api request.
I have been through numerous examples on the Azure site and others and all of them are handling the logon/obtaining the token in the client web app.
Is this even possible?
UPDATE I just realized (as pointed out by #Darrel-Miller that you don't really want to allow the user to put the credentials in.
The only thing that is still unclear to me, is where do you want to provide the credentials for AAD?, What is it exactly what you would like to accomplish.
Even more, why would you use AAD if there no user interaction at all.
If all that you want is a secure connection you can just use the standard application key for the web api without enabling AAD. And its as pretty straight forward to just add the MS_ApplicationKey to your header and you are good to go.
As you described in your comment you have a webclient that tries to do the requests and gets the 302, that is why my original answer wast that you would use ADAL. But now that I get deeper into what you want probably what you want to use is KurveJS :
https://github.com/MicrosoftDX/kurvejs
And it has the AAD app model v2 with Active Directoy B2C.
This makes it easy to add third party identity providers such as Facebook and signup/signin/profile edit experiences using AD B2C policies
You can read more about it here:
https://github.com/MicrosoftDX/kurvejs/blob/master/docs/B2C/intro.md
Do you mean this??
https://msdn.microsoft.com/en-us/magazine/dn463788.aspx
Just use ADAL nuget package to handle the call...
You can read this from the post:
As soon as the execution hits the call to AcquireToken, you’ll get the authentication dialog shown in Figure 8. ADAL takes care of contacting the right endpoint and rendering the authentication experience provided by the server in a pop-up dialog without requiring you to write any UI code.
I hope this works for you!

Authentication strategy between my chome extension and server

I'm in the process of building a Google Chrome extension, and have some questions about how to implement security into the application.
I need to access a couple of Google API's so am going to be using OAuth 2.0 for that. So basically from the extension I know which user is logged into the browser.
My extension then needs to get and post data to my (nodejs) API service. I want to ensure that the user requesting data is the same user that is logged into the browser. Is there any way of using the previous Google authentication process to also authenticate communications between the extension and my API? I dont really want the user to have to log in again, to access my API.
I'm sure I'm missing something simple, and I've not been able to find anything that fits this scenario
Follow the OpenID Connect auth flow and you will get an access_token and an id_token. The acess_token you will use to use to make authenticated requests to Google APIs as usual. The id_token will be used as authentication with requests to your server.
When the requests hit your server you will need to validate the token and you can then use the contents of the id_token to identify the user.
User wouldn't have to login on auth process provided if user is already logged in and you are using a web application flow (not chrome.identity APIs) but user would see the consent screen atleast the first time. However you can skip the account selector screen if you already know the email address by providing &login_hint= parameter.

OAuth authentication and consumer secrets

I have a webservice which acts as backend for smartphone apps.
I want to be able to authenticate users as painless as possible, but even though I thought I understood the OAuth I must admit there are some missing pieces here and there.
Authentication:
Let's say the user has an Android phone. He is probably already Authenticated to Google and it would be really nice if I could just extend this authentication to my webservice. Android has OAuth support so the users opens his app, grants permissions to use his google account and the app authenticates him to the web service.
Web service
Since the service should accept users from all kinds of devices it should not be Google specific. It should be possible to register an account and login from any device. I'm unsure if it is possible to register a new account with OAuth alone or if you need some other kind of authentication first - OpenID for instance.
How would the flow be for the generic webservice? A generic API for registering a user and granting him access to an API?
Furthermore - I do not want to control the devices connecting to this service. I can see OAuth requires a consumer_key and a consumer_secret. If I run everything through SSL - is the consumer secret still secret or can I just use some dummy values? Thus avoiding creating a device-registration system where people can acquire a consumer_secret?
For your case, if you want to use Google/Facebook etc as authentication providers, you will need to use the 'Authorization Code' flow of Oauth2. In this case, you register with Google/FB as a developer and get a client id and secret for using their API.
Then you obtain the Login with Google/Facebook button and code, which you will use to fire a "webview" or an embedded browser where the user will be taken to google/facebook and asked to provide his login credentials.
Upon success, an authorization code will be sent to a redirect url that you would have provided while registering as a developer at Google/Facebook. You will need to catch this authorization code and then again call the relevant API to obtain the access token, which you can then use to fetch the user's details to register him in case of first time or authenticate him if he's already registered through this method earlier.

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