Prevent logins to unauthorized AAD tenant? - azure-active-directory

Is there a way to prevent users from logging into their own AAD tenants? For example, allow login to contoso.onmicrosoft.com but not fabrikam.onmicrosoft.com.
My customer has a highly-controlled Azure environment where they are running some servers and PaaS/SaaS applications. Users connect to those servers are use a variety of Azure services and some SaaS (primary concern is PowerBI). They’re concerned that a user could login with a non-company account (wahid#hotmail.com) and then upload sensitive data their own PowerBI workspace.

You cannot prevent a user who has already been in the tenant to login to that AAD tenant, except deleting the user from that tenant.
If one account was created/invited to one tenant, the user just can login to that tenant.
For the scenario you described, I suggest you could revoke the Product license for those users. If you don't assign product license to the user, the user cannot use that App or cannot see that app in My Apps panel. For other SaaS/PaaS app(Web App), you may use user assignment to allow specific users to access the App.

For others: Daniel answered this for me. Short answer, this isn't easy, you would need to inspect the response body for the tenant ID (or name) and then block it. This would also lead to a poor user experience but that's all we can do today.

Yes, you have a few options.
Option 1: Single tenant apps
If you have the ability to create apps in the tenant you want to accept users from, you can mark your app as available to only this tenant (the field is called availableToOtherTenants). This will notify the token service to only authorize access from users in the tenant the app was created in.
Option 2: Multi-tenant app w/ token validation
The other option is to mark your app as multi-tenant (same field as above, just set to true) and implement logic in your app to validate the user's tenant from which the token was issued.
In this scenario, you will need to have some kind of web service that can safely validate access tokens (.NET code sample on this). To check the tenant the user's account belongs to, you'll need to validate the iss field. It'll look something like this,
"iss": "https://sts.windows.net/7fe81447-da57-4385-becb-6de57f21477e/"
in which the GUID represents the tenant ID. This allows your web API to have an allow or deny list based off tenant IDs.
More help
Here's an excellent blog post on token validation.
Azure AD Developer Docs
.NET Web API Code Sample

Related

Include Roles from external database in the Access Token

I am doing login from Azure AD.Client is SPA(angular using MSAL). If user is not Authenticated, it redirect to Microsoft Login Screen (using MSAL). On successful login, it return an access token.
My roles will be stored in a database. I need to add the roles of that user as part of claim in access token. I am not finding the way to do it.
I do not want to make another call from SPA to API to get the DB roles.
Please suggest some good approach.
Any links explaining the approach will also be very helpful.
I am still in design phase but not able to find the best approach.
In one microsoft site, i found that we can fetch the roles from DB but details were not there.
most of the places, it is written that we need to provide roles in Azure AD users menifest file.
In regular Azure AD, the "roles" claim is exclusively sourced from app role assignments for the signed-in user (or groups the user is a member of), to the app roles for the app the user is signing in to.
There's no feature currently in Azure AD which will connect to an arbitrary database, make a database query in the appropriate form, and include the results in the roles claim in the resulting ID Token.
I can think of three options to achieve your scenario:
After sign-in, call an API to retrieve the roles. Though you mention this is not desirable, it's probably the simplest approach, so it's worth listing. As a result of the user's sign-to you app, you app will usually obtain an access token to an API. If you set up your API to be secured with Azure AD (directly, or through Azure API Management), your SPA could simply get the necessary access token as part of sign-in, and at that point it's trivial to make a REST call to retrieve the role details for the user (and possibly other information useful to rendering your app).
Synchronize (or copy) your role information from your database to Azure AD. For each role, create an app role in the Azure AD app registration. For each user-role association, either create an app role assignment to directly assign the user (user -> app role), or assign a group to the app role and add the user to the group (user -> group -> app role. Keeping this in sync is probably not trivial, so if your scenario allow to move the role information to Azure AD app role assignment, you can forget the database entirely (making Azure AD the authoritative location). Of course, this might not work for your specific case.
Use Azure AD B2C and a custom sign-in policy. You could create an Azure AD B2C tenant, set up a custom sign-in policy to use your (regular) Azure AD tenant as the identity provider, and configure the policy to enhance the claims by calling a REST API to retrieve your roles. In this approach, you still need to have a REST API which can provide the role information, so rather than doing the setup and migrating your app, you may prefer simply calling the API from your SPA (option 1, in this list).

Why do i need to create a Multi-Tenant App?

I have been doing some R&D on using the MicrosoftGraphAPI to fetch the skus subscribed by my organization.
I have created an app as described in the documentation. I did all the steps in the above link except 'Assign application to role'.
Using postman am able to get the oauth2 token by sending a post request using the link
https://login.microsoftonline.com/<mytenantid>/oauth2/token
with the client_id, client_secret, resource(https://graph.microsoft.com) and grant_type(client_credentials) parameters.
After this token is obtained I can fire a get request https://graph.microsoft.com/v1.0/subscribedSkus with the Authorization header set as Bearer {token} which will return the SKUs subscribed by my organization.
So far so good. :-)
Now the requirement is I need to fetch the subscribed SKUs by one of the client (let's say having the azure ad tenant id 'ABCDEFG') of my organization.
I can successfully do that by registering an app in the client's tenant 'ABCDEFG' with the same steps as above.
This approach is fine if my organization has say 1 or 2 clients.
However, if the client numbers are more than say 30 this approach of registering an application in each Azure AD instance is not feasible.
If the application that I registered in my organizations AAD was multi-tenant then how should it help me?
What will be the steps needed to obtain the access token for each tenant?
Can somebody assist with some detailed explanation?
Since you need application-level access, you would assign one of the Application permissions listed in the documentation for getting SKUs: https://developer.microsoft.com/en-us/graph/docs/api-reference/v1.0/api/subscribedsku_list.
Directory.Read.All, Directory.ReadWrite.All
In this case you should require the Read Directory Data (Directory.Read.All) application permission.
Then you mark your app as multi-tenanted.
Now then in order for another org to use your app, they will have to be on-boarded.
You will need some kind of page where their administrator can click a button/link to start using your app.
This should redirect the admin to:
https://login.microsoftonline.com/common/oauth2/authorize?client_id=your-client-id&prompt=admin_consent&response_type=code+id_token&redirect_uri=url-where-to-send-user-back
Once they sign in, they will be presented with a consent screen, where they can approve the permissions that your app requires.
If and when they do that, they will be redirected back to your app (to the URL you specified) and you can use the Id token to know which Azure AD tenant registered.
During this process a service principal for your app is created in their tenant, and the required permission is granted to it.
This means you can then get an access token for their tenant from: (using the same credentials)
https://login.microsoftonline.com/their-tenant-id/oauth2/token
Remember that access tokens are specific to an Azure AD tenant, so you will have to get an access token for each tenant.
One thing I would like to point out is that you should instead try to use delegated permissions if possible.
The application permission given here gives quite large access to your app, and some admins might not use your service for that reason alone.
Delegated permissions are more complex to handle, but allow your app to act on behalf of a user instead of purely as itself.

Multi-tenant app in Azure AD (Active Directory) fails with AADSTS50020

I created a "Web app / API" app in our organization's "xxx.onmicrosoft.com" Azure Active Directory. The app's "Multi-tenanted" property has been set to "Yes".
We configured OpenID Connect (we use https://github.com/mitreid-connect/) to use the following URLs:
https://login.microsoftonline.com/common/oauth2/authorize
https://login.microsoftonline.com/common/oauth2/token
Please note that we used "common" in the URLs and we didn't use "xxx.onmicrosoft.com" because we want people from outside "xxx.onmicrosoft.com" to be able to authenticate and access our app.
With those settings, the people from xxx.onmicrosoft.com can properly authenticate and access the app.
However, when I use my personal live.com account (with username xxx#gmail.com) to access the app, I get AADSTS50020 error. I am able to properly authenticate with my xxx#gmail.com account, but I do not get redirected to the Reply URL. I'm stuck on Microsoft's Web page with the following error msg:
AADSTS50020: User account 'xxx#gmail.com' from identity provider
'live.com' does not exist in tenant 'xxx.onmicrosoft.com' and cannot
access the application '391e7103-ZZZZ-zz87-xxxx-7xxxxxd5xxxx' in that
tenant. The account needs to be added as an external user in the
tenant first. Sign out and sign in again with a different Azure Active
Directory user account.
What configuration do I need to change if I want people from any identity provider to be able to access my app ?
Like it has been stated here, I expected that people from anywhere could access my app without requiring more configuration on my side.
I'm asking this question because I'm in the process of getting certified for AppSource and this currently blocks me from being able to do so.
AppSource only requires work accounts to sign-in. You are using an #gmail account - which is a personal account - and because you are using the Azure Active Directory v1 endpoint in addition to common (https://login.microsoftonline.com/common), it can't accept personal accounts to sign-in directly - only work accounts.
You have three options:
If sign-in personal accounts is not a requirement for your application, then you can continue using the v1 endpoint and use a work account to sign-in/test your application. This will make you ready for AppSource certification.
If you need/ want to allow personal accounts in your application in addition to work accounts, then you can consider using the v2 endpoint (https://login.microsoftonline.com/common/v2.0) for Azure Active Directory. The v2 endpoint allow both personal accounts and work accounts to sign-in with no effort.A note is the v2 endpoint has some limitations: if you can live with these limitations (for example, your application only needs to sign-in users and eventually make queries against Graph API), then in general it should be fine to use, but if you need extra features like protecting your own Web API with scopes, then this feature is not released at this point (as November 2017). Please read this document for an updated list of limitations of the v2 endpoint.
A third (but less recommended option for AppSource) is to keep using the v1 endpoint and make your application to be single tenant - which is to change the endpoint from https://login.microsoftonline.com/common to https://login.microsoftonline.com/{yourtenantid}, and then use B2B invitations API to invite every external users (including work and personal accounts) to be part of your Azure AD tenant/organization. More information about B2B here as well.
The option '3' above have some consequences for management as well for AppSource: by using this option, you are required to have one Azure Active Directory tenant (if you don't have a tenant already, you can get one using these instructions), and the users being invited will be guests accounts of this tenant - this mean that you need to invite every external user to your application/ tenant. A multi-tenant application allows any user from any organization to sign-in to your application with less management on your side. In general for SaaS applications, multi-tenant configuration is recommended.
For AppSource, also the option '3' leads to a less-immersive user experience (Partner led trial), where the end user won't be able to access your application's demo right away - mainly because that they have to wait for the invitation's email and accept it (user has to accept being guest of your tenant) so that they can access your application.
For more information about AppSource requirements and trial options - please see this article.

Multi tenant Daemon office 365 app registration on consumer AAD by granting admin consent, Does it also require separate registration on consumer?

I am developing a multi-tenant Office 365 daemon that requires access to user calendars.
I have successfully registered in the company tenant (Tenant1) that has deployed this app using certificates and I am able to get access tokens.
Now I created a separate AAD tenant (Tenant 2) and logged in to daemon app using administrator account of Tenant 2, it prompted the Admin Consent screen and I provided consent. There was no errors returned.
When I tried to get an app token however, I am able to get a token but with blank permissions. If I call the Office 365 API using this token, I get a 401.
I was of the view that service principal objects should be created. Also I am unable to see this app in Tenant 2 app registrations.
Do all my consumers have to register this app manually in their AD tenant and modify application manifest file to add certificate details?
I am not sure about the benefit of multi tenancy if that's the case.
I found the follow in the Azure Active Directory documentation:
The following diagram illustrates the relationship between an application's application object and corresponding service principal objects, in the context of a sample multi-tenant application called HR app. There are three Azure AD tenants in this scenario:
Adatum - the tenant used by the company that developed the HR app
Contoso - the tenant used by the Contoso organization, which is a consumer of the HR app
Fabrikam - the tenant used by the Fabrikam organization, which also consumes the HR app
You do not need to have each tenant register your application. In fact, you shouldn't since having dozens (or hundreds) of unique App IDs floating around would only create headaches for you.
Each tenant does however need to execute the Admin Consent workflow. This will authorize the App ID you've registered on your end to access the scopes you've requested.
Generally, I recommend using the v2 Endpoint and the apps.dev.microsoft.com portal for registering your app. While you can also register your app in your own Active Directory, the portal makes it a lot easier to manage.
The general process is:
Register you application in the Registration Portal
Populate the "Application Permissions" in the Microsoft Graph Permissions section.
Launch the Admin Consent workload using https://login.microsoftonline.com/common/adminconsent?client_id=[APPLICATION ID]&redirect_uri=[REDIRECT URI]
Get a beer
A couple of tips:
The Registration Portal only supports MSA (i.e. personal) accounts at the moment. I'd suggest creating a new Outlook.com account for this purpose so you can easily share the credentials with folks who need them internally.
If you create a shared Outlook.com account, you should also set up forwarding rules for all of the interested parties internally. This is in case something should every go wrong or change down the road and you need to recover the account.
I wrote a v2 Endpoint and Admin Consent primer that you might find helpful. They assume you're using the Authorization Code flow but the concepts remain the same for Client Credentials.

Querying a tenants Azure AD from a multi-tenant Application

We have a multi-tenant Saas application providing sign in using our username/pwd authentication system and using Azure AD (OAuth 2.0 flows). When a user signs in using Azure AD, we can get the user's profile using https://graph.windows.net/{tenantid}/me. We want however to get more information using the memberOf or getMemberGroups operations to retrieve the user's groups in the tenants directory, to map specific groups from the tenant to an organizational structure in our application. However these operations always fail with a Forbidden statuscode. Are we missing required permissions or is it just not possible to query for the groups and roles of another tenant.
Thanks in advance
This is totally possible, but today requires that you request the "Read Directory" permission. This permission does require and admin of the tenant to consent. We are looking at adding some additional fine grained permissions for Graph API that will allow users to consent (to get group membership information).
Another option for you is to configure your application to request group membership claims (which should appear in any user or JWT token). You can do this by going to the azure management portal and getting to your app's config page. From there download the application manifest file and update the groupMembershipClaims property. You can see most of the properties in the application manifest described here: https://msdn.microsoft.com/en-us/library/azure/dn151677.aspx. Once updated, you can upload this app manifest file, and this will configure your application accordingly. Once done, AAD will issue group membership claims in the token. Dushyant has written a nice blog about authorizing access to a web app, using group membership claims or app roles. You can find it via Alex Simons blog post here: http://blogs.technet.com/b/ad/archive/2014/12/18/azure-active-directory-now-with-group-claims-and-application-roles.aspx
HTHs

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