I have a .NET Web API with a bunch of end points/methods that an Angular App calls. I want to now implement the login system against our active directory, and wondering what my options are.
Back in the days, it was simple: windows or forms authentication, and then just some simple configuration in the web.config, and may be a custom provider. But now it seems like there are a lot more options with OWIN, OAuth, token based authentication, etc.
Where do I start? I have a form with username, password, and a login button on the Angular app, and I have the active directory in the backend. What should happen after the user hits the login button? Any direction would help.
Thanks.
Well, it depends on what you actually need.
If you want to authenticate only AD users then you can try authenticate in AD on their behalf and in case of success you return either token or authentication cookie.
But I don't think it is a good idea to make users use their domain password unless you have two factor authentication.
It's better to extend AD schema with additional data for authentication through your service or even to have standalone auth server with associated domain user info. Look how it is done in SQL server (but in reverse direction): you need to define internal user corresponding to domain login. This approach allows you to have users that do not belong to AD, sometimes this can be important for outsourcing some tasks.
Look at IdentityServer
Related
We are building several websites/products, if a user has an account on one site they will also be allowed access to all other sites.
Let's say we have the following setup:
Clients
site1.com
site2.com
Single Sign On Portal
sso.company.com
APIs
api1.company.com
api2.company.com
The Single Sign On Portal supports multiple OAuth providers, such as Google, Microsoft, Facebook, etc and this is all working great built on top of the default ASP.NET Web Forms template in VS 2015 using OWIN and Idenity.
The SSO site is logging the user in an using a cookie for authentication, which works fine while still on the SSO site. Now we need to return a token that the client site can use to know that the user is authenticated
Now the challange here is how do we exchange the cookie to a token that we can return to the client(s) to use in the Authorization header in request sent to our APIs?
Should we generate a token our selves or is there some built in functionality we can use for this purpose?
I've seen most people generate a token themselves and then multiple accounts can be linked to that same user in your account (i.e. a user could log into both FB and Google). Most of the SSO providers have a way to get an identity token or one time use code for your server to use and get user info like FacebookId. The key is ensuring that identity token came from FB and not a third party.
Auth0 is a pretty good service if you want a managed route. Even if you don't use them, they have a lot of good resources on oauth. (I have no affiliation with them other than that we used them before.) we also have a little more info on auth: https://www.moesif.com/blog/technical/restful-apis/Authorization-on-RESTful-APIs/
What is the best method of securing a REST Web API with the following requirements. The system has an Angular JS frontend with the REST APIs implemented in ASP.net.
There are two "roles" in the system, users will have one of the
roles. One role should allows access to some APIs (call it "VIEW"),
the other role allows access to other APIs
All users are in Active Directory, so if I have a username, I can check what role they are in- Some clients are on Windows boxes, the others are on Linux
I would like to persist the session so I don't have to look up AD for every API call
I would like single sign on. On the Windows machines, I don't require them to enter user and pass as I already can retrieve their username using Windows Authentication.
I believe that Oauth would be my best option.
There are two "roles" in the system, users will have one of the roles.
One role should allows access to some APIs (call it "VIEW"), the other
role allows access to other APIs
For role based authentication, you can use [Authorize("Role" = "Manager")]. The token will be provided by the identity server and will contain the claim as Role.
All users are in Active Directory, so if I have a username, I can
check what role they are in- Some clients are on Windows boxes, the
others are on Linux
If you have ADFS then you can have an Identity server that trusts the ADFS. The ADFS will provide a token which will have the claim for role and your Identity Server will do the claims transformation and will return the same Role claim back to angular app.
I would like to persist the session so I don't have to look up AD for
every API call
For this while requesting the token, you can ask for offline scope so the Identity server will provide the Refresh Token with Access Token so you don't need to ask for AD again and again.
I would like single sign on. On the Windows machines, I don't require
them to enter user and pass as I already can retrieve their username
using Windows Authentication.
For this one, you can have your Identity sever trust the WSFederation for windows Authentication.
So basically you need to setup Identity server that will provide you with the token and the REST API will use that token to verify claims to return the correct information back to the user.
I am not sure what you expect exactly. Anyway, first I'm gonna reformulate your question with requirements:
you accounts and role are in active directory
you want to manage roles based on an active directory group
you want anybody whatever the system (windows, linux, mac, mobile...) to connect on your application using the same authentication
you want to avoid your AD to be hit constantly (not at any call for example)
if the user is connected on an application that uses the authentication system, he doesn't have to do it so again on another application that uses the same authentication system
If these requirements are yours. I believe the only standard (and clean) solution is to use OAuth. I'm not gonna go in detailed description of OAuth, but this authentication protocol is the most standard one on the net (facebook, google, twitter...). Of course as you don't want to use facebook, google or twitter accounts in your business applications but your active directory accounts you'll have to install/setup/develop your OAuth identity provider using accounts of your active active directory server. Your choice will depend on how well you know ADFS protocol and its different flows (code, implicit, assersion) You have two solutions for it:
Use ADFS: install ADFS; it provides a OAuth portal that will work out of the box with asp.net mvc. This uses the code flow of OAuth that is the only OAuth flow supported by ADFS. For roles and its related AD groups, you'll have to map role claims with AD groups. (it's in the setup of adfs, you'll find many tutos on the net). You'll find lot of tutos as well about how to use ADFS with asp.net mvc/asp.net webapi. I mention .net here, but every technology has an implementation for OAuth authentication (nodeJs/express, php, java...).
Use thinktecture identity server (.net technology). This will provide all the foundation to implement a custom identity server with the least effort: http://www.thinktecture.com/identityserver / https://github.com/IdentityServer/IdentityServer3. It contains an addin to plug its accounts to active directory. With this, you can use implicit and assertion flows.
Use oauth2orize (for nodeJs): https://www.npmjs.com/package/oauth2orize. This will permit you to make the same than thinktecture identity server but in nodeJs. Apparently you'll have to make all the wirering with ad manually. With this, you can use implicit flows (not sure about assertion flows).
At application side, most of frameworks can authenticate easily using OAuth with a lot of existing frameworks. For example, even if you make a single page application, you can use adal.js or oidc.js for angular if you use angular. As I mentioned above, all this is taken in charge by asp.net mvc/webapi out of the box but I know it's the case for other server technologies. If you have more questions, don't hesitate as I'm not sure of what you expect exactly.
I need a good advise and wanted to know whether a solution is feasible or not. Right now one of my customer has a common login application which is based on Forms authentication(ASP.NET) using membership provider. All internal users use their AD credentials to logon and external users use custom username and password. Both are wrapped via Forms authentication. Now the new proposal is to replace this Forms authentication with ADFS. I have gone through various articles over internet and not able to come to a conclusion. Let me list my findings so far with ADFS extension points.
1) It is possible to add a custom attribute to ADFS claims by the approach mentioned in https://blogs.technet.microsoft.com/cloudpfe/2013/12/27/how-to-create-a-custom-attribute-store-for-active-directory-federation-services-3-0/.
2) It is possible to add a second level of authentication( or multifactor authentication) via the approach https://blogs.msdn.microsoft.com/jenfieldmsft/2014/03/24/build-your-own-external-authentication-provider-for-ad-fs-in-windows-server-2012-r2-walk-through-part-1/. Here I understand that after first level authentication done by AD then only our external provider will come into picture.
So I have a general question that is it really possible to achieve what I am looking for with ADFS. Please let me know.
This is based on where the user accounts are stored. If both internal and external users are in AD, you can just redirect to ADFS.
If internal is in AD and external is in an untrusted or other LDAP source, using ADFS 2016 you can link to both these account stores and still offload authentication to ADFS.
If external is in SQL, you can either use a virtual directory in front to project it as an LDAP store (previous option) or use IdentityServer.
If externs is something else, you'd need IdentityServer.
Thanks //Sam (#MrADFS)
Yes - you can add a custom attribute store.
Yes - you can add a custom authenticator.
A better way might be to use thinktecture's IdentityServer 3.0 for the ASP.NET Identity part and then federate IdentityServer and ADFS.
We are going enhance the authentication and authorization system of our Intranet web app. After having few days reading about ADFS, STS, claim based authentication, asp.net Identity. Still not sure how these things works together.
Most of our intranet web applications are using Windows Integrated Authentication, we uses windows group or AzMan to do role base authorization. We have few applications(Vendor application) use it own user database and form base authentication.
We want to add following features to our web applications.
For Windows Authentication application, we want to let user to Sign Out / Sign in as different user. So when User A using his/her computer to access the application, it will auto logged in (default windows integrated authentication). When he/she do log out, it will redirect to a form to allow to input other user credential.
We want to allow user login to System A using System B username/password.
e.g. For the windows authentication application, we want allow user login to the application using the credential of the Form base application (Vendor application) of via visa
I don't know if ADFS can solve these two problems.
From my understanding, the main purpose of ADFS is to allow access to internal application from Internet, and it require SSL.
Our application all are in Intranet, and we don't want to manage the ssl cert.
But by using ADFS, perhaps I can enable both Windows and Form Authentication on my application, so then let use log out and re-direct him to the login form as which just like he access outside company network. It should solve the problem 1.
For problem 2, what if I can create a custom STS to issue security token by using the user database of the form base authentication appliaction. Then I can use claim based authentication and allow one application can use ADFS and my STS. It should solve my problem 2.
Is my direction correct? or am I complicated the problem?
ADFS will not work without SSL.
Furthermore, all RP have to use SSL.
Internally, users will be logged in seamlessly using WIA. When they logout, they will simply be seamlessly logged in again.
Also ADFS v3.0 and below can only authenticate against AD.
While what you want is possible using ADFS, the question is whether it's a good idea and worth the trouble. It may be more appropriate to ask the user to log out of the machine and log in with a different account so you can stick with Integrated Windows Authentication (IWA). Writing your own security infrastructure is fraught with peril.
If you really feel these are hard requirements and it is worth the trouble, the following may work.
Write an ASP.NET web application based on Katana and enable Integrated Windows Authentication. This will make sure that the first time a completely unauthenticated request comes in, the application will challenge the browser. Subsequent requests will have a WindowsPrincipal populated in the HttpContext.User and Thread.CurrentPrincipal.
Now, write a piece of OWIN middleware that checks if an authentication cookie is present. If the cookie is not present, it checks the Thread.CurrentPrincipal and serializes the claims into a secure cookie.
If the security cookie is present, it overwrites the WindowsPrincipal in Thread.CurrentPrincipal with a new ClaimsPrincipal created from the claims in the cookie.
Now, when a user navigates to the web application the first time, he/she will be logged in automatically using IWA and the cookie will be created. Now, provide a logout action which deletes the authentication cookie and presents the user with a username and password dialog.
In the POST handler for that action, use WIF to talk to the username endpoint in ADFS (using WS-Trust protocol) and try to authenticate the user with the supplied credentials. If successful, use the claims from the returned token to create a new authentication cookie.
I am relatively new to uisng ADFS (in ASP.NET) which is what my company wants to use and just have a few basic questions about that:
Am I correct there is no explicit "Authorize" call you can do like with ASP.NET Membership Providers? Unless you on a domain it presents you with a login screen and once you enter credentials it does validation and returns back a token with claims information.
Can you configure some forms to allow anonymous access like you can do with Forms Authentication?
Thanks.
Yes, you can setup pages in your app that don't require authentication. It works exactly like you'd do with Forms Auth.
On #1: in a claims based model, your app relies on an external system to authenticate users and receives evidence that the user is valid in the form of a token. You can completely automate this (using WIF and config files), or you can explicitly trigger the authentication process. In any case, your app won't be responsible for validating legitimate users anymore. It is a responsibility that it delegates to the STS (e.g. ADFS). That's why apps are called "relying parties".
I'd suggest you read the first couple chapters of the A Guide to Claims based Identity for a better understanding of the underlying principles.