What's the best way to authenticate a user in a .net core 2 API programatically using Azure Active Directory - azure-active-directory

I'm working on an application that has an angular 6 front end and a .net core 2.0 back-end and am trying to set it up so that my application authenticates users via Azure active directory. The issue is that I want the .net core back-end to do all the authentication programmatically when I have the front end pass an email and password. Everything that I've seen so far online suggests to have the front end redirect to the Microsoft login page but we are using our application as a boiler plate project and want to be able to change the type of authentication easily in the back-end without having to change the angular front-end. Does anyone know how I could go about this?

You can use Resource Owner Password Credentials Grant .The process will like that you collect the user credentials in Angular app and post to .net core back end , then finish the authentication in back-end app with user's credential. But that is not recommended because The ROPC flow requires a high degree of trust and user exposure and you should only use this flow when other, more secure, flows can't be used.
Also :
The Microsoft identity platform endpoint only supports ROPC for Azure AD tenants, not personal accounts. This means that you must use a tenant-specific endpoint (https://login.microsoftonline.com/{TenantId_or_Name}) or the organizations endpoint.
Personal accounts that are invited to an Azure AD tenant can't use ROPC.
Accounts that don't have passwords can't sign in through ROPC. For this scenario, we recommend that you use a different flow for your app instead.
If users need to use multi-factor authentication (MFA) to log in to the application, they will be blocked instead.
Reference : https://learn.microsoft.com/en-us/azure/active-directory/develop/v2-oauth-ropc

Related

Permissions for SAAS in Azure AD

I am looking to develop a SAAS product where tenant from different organizations can log into my application and there are specific set of custom Permissions that I want to create for my application which will allow users to access different endpoints in my application.
Application is hosted in a inhouse server.
Can someone please help me to understand what would be my approach to do so?
I am doing App Registration in Azure AD. And in the redirect uri I am passing my application url.
I am stuck after that.
I tried to reproduce the same in my environment and got the results like below:
To integrate the SaaS Application in Azure AD, Register an Application in Azure AD.
As you need tenant from different organizations log into the application, make sure to configure the Application as Multi-Tenant like below:
Based on your requirement you can select the API permission which you want the users to access like below:
For sample, I selected Microsoft Graph and added the required API permissions:
You can choose Delegated or Application API permissions based the Grant Flows.
For Client-Credentials, need to grant Application API permissions and for Authorization Code Flow need to grant Delegated API permissions.
For sample, I am using OAuth 2.0 authorization code flow to generate the token for authentication.
I generated Auth-Code using below authorize endpoint:
This will authorize the request and redirect it to the application.
I generated the token using below parameters:
Using the above generated Access token, you can call Microsoft Graph API.
If you want B2B collaboration, refer to the document provided by bahrep in the comments.
References:
Register a SaaS application - Azure Marketplace | Microsoft Learn
Microsoft identity platform and OAuth 2.0 authorization code flow - Microsoft Entra

How does client credential flow work in Workload identity federation?

For my current ASP.NET Core MVC application I authenticate directly with a web app registered in Azure AD Portal. This provides me with an access token so on the backend of my web application I can use MS Graph with my users specific account (ie add files to their onedrive , email, etc). However, my organization also has Okta which a lot of applications authenticate against. So I was trying to determine to authenticate through Okta (which has a much cleaner sign in process IMO) as well as authenticate against Azure AD and get an access token. Through my research I found something in my web application registration in Azure AD called Workload Identity Federation. This led me to this useful video
https://www.youtube.com/watch?v=wZ0gCJYMUKI
and also microsofts info site:
https://learn.microsoft.com/en-us/azure/active-directory/develop/workload-identity-federation
This seems to answer what I want which is to use Okta but allow me to still use MS Graph for my users since it will authenticate against Azure AD (correct me if I am wrong and this is for something else). My issue is none of these resources really go into depth regarding how the access token is passed to my application so I can use MS Graph. My research this is called client credential flow since my application only has delegated permissions so it requires the users to log in and it basically allows my web app to act on their behalf when using MS Graph. So I am trying to understand and fill this void of information regarding how client credential flow fits into Workload Identity Federation and is this the solution to my problem.

Protractor-net and Azure AD

I'm new to Protractor and am wanting to write C# tests that run against an Angular 8 application. The problem is, the application uses Azure AD for authentication and I don't know the correct approach to authenticate automatically when running the test. If I navigate to the application URL it redirects to the Microsoft login page for authentication but I can't seem to access this.
You can use the libraries given by Microsoft to implement applications for authenticating to Azure.MSAL is one of the libreary whiich is best to use. If you want to use MSAL to acquire a token, you need to:
Register an application in Azure AD.
Add target API, and grant consent to select permissions.
Generate a secret key.
Then you can get a token as Acquire a token and call Microsoft Graph API.
However, I think what you really want is to integrate AAD. You can easily enable AAD authentication for your .NET web application. It uses OWIN middleware.

Identity Server + resource owner credentials + authenticator

I'm working on setting up a new SSO application. I would like to use ASP.NET Identity as a database to store the users data. I have a ReactJs application hosted on Node.JS and a .Net Web Api2 application. I want to protect thsi Web Api 2 using Identity Server with users from its database. In further development I'm going to create a mobile application.
I'm able to create an asp.net identity database with some users and use Resource Owner credentials, but I have couple of questions if anyone could help:
Why is Resource Owner Credentials not recommended? My current workflow is to hit the api with client&user&password and obtain a token which I store in web layer and use in Web Api requests. Web Api validates the tokens and identify the user. I read on IS page that's not recommended then what's the recommended scenario to authenticate the user?
How can I create an authenticator for mobile? Should I create my own certificate issue, store it in database as a thumbprint and use access token for that?
Thanks
In short, Resource Owner requires the credentials to be passed through the application itself, also RO doesn't give you SSO. Here's a longer answer. The recommended scenario is to use hybrid flow with PKCE enabled.
Look up TOTP. I believe it is implemented in AspNetCore.Identity with some examples.

Multi-tenant ADAL JS SPA along with an Azure AD web application back-end

I'm currently trying to implement a multi-tenant Azure AD application that will use Microsoft Graph API's to monitor and analyze Office 365 "metadata" for members of the tenant domain. For example, the application might monitor One Drive user space over time. The architecture of the application will include an AngularJS SPA client along with a web application back-end. The idea is that the web application allows for both local registration (e.g. traditional sign up using an email address and password) in addition to Azure AD authentication. In the case of local registration, the user might be able to associate an Azure AD tenancy with the local account in the future, for example.
I'm struggling to understand how various authentication mechanisms should work. For example, I think that there should be two levels of authentication in the case of Azure AD: one authentication for the users of the client SPA, and another authentication used by the back-end for making continuous calls to the Microsoft API's, requesting refresh tokens, etc.
How might this architecture be implemented using the various Azure AD authentication scenarios Microsoft has already provided examples for?
If my initial inclination that I will have two applications registered with Azure AD (for example, the SPA registered as a native application, say, and the web application registered by itself), how will users allow access to both of them, and what would this workflow look like? In addition, what would the flow of user requests look like? The SPA would make a request to the back-end using its Azure AD token, but what will the back-end do to receive its authentication token and make calls to the Microsoft API's?
How might I best incorporate Azure AD authentication along with local registration into my application?
Generally speaking, you can associate your each user to his entity in Azure AD tenant in your backend server / database. As every user in Azure AD has several unique properties in the entity object. You can use the user's email or objectId as mentioned at Claims in Azure AD Security Tokens as the external column in your user table.
When your user authenticate your site via ADAL.JS, you can grab the access token in your backend server via the Authentication header. You can use the access token to request for the resources protected by Azure AD. And the access token is a JWT token, which you can decode directly to get the user basic claims as we mentioned before. You can retrieve the claim which you stored in your user table and match the special user registered in your server for requesting the resource protected by your self.

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