Tag Archives: Sites.Selected

Sites.Selected is a new feature for Azure registered apps. It allows an application access to a specific SharePoint site collection via MS Graph API and SharePoint REST API.

Automating Sites.Selected permissions provisioning

Scenario

You administer Microsoft 365 SharePoint Online. Part of your daily activities is providing Microsoft Graph and SharePoint Sites.Selected API permissions to other users (developers).

In Aug/Sep 2023 Microsoft pushed an update that prevents site collection admins to create or update an Azure Access Control (ACS) principal (that was the way most of developers used to get Client Id and Client secret to access SharePoint site). So your users are probably getting something like Your SharePoint tenant admin doesn’t allow site collection admins to create or update an Azure Access Control (ACS) principal message attempting to create or update SharePoint App-only principal at AppRegNew.aspx or AppInv.aspx pages. Here are more details on the issue.

Microsoft and MVPs shared some technique how to provide Sites.Selected API permissions, but dealing with scripts manually, elevating individual permissions every time you need to run the script – it all takes time and not very efficient. More and more devs are reaching you on the app. So you want to automate this process.

Solution

Solution architecture

My way to automate it includes:

  • SharePoint list as a frontend
    here you can accept intake requests, organize approval workflow and display automation results
  • Azure Function App as a backend
    here will be your PowerShell script hosted that runs on scheduled basis and takes care of actual permissions provisioning

Solution details

High-level, getting application permissions to some specific SharePoint site is a two-step process:

  1. get application registration in Azure and properly configure it
  2. get permissions for this application to a specific SharePoint site

For the first step – check this and this articles. I’ll focus on the second step below.

You can provide Sites.Selected permissions for the app to a site with

I will be using second one one. Also PnP.PowerShell will be used to get access to SharePoint intake site and read/update requests from SharePoint list and so on.

Azure App Registration

I registered an admin Application in Azure – “SharePoint Automation App”, added Graph Sites.FullControl.All and SharePoint Sites.FullControl.All permissions, then added Microsoft Graph Directory.Read.All permissions and got tenant admin consent:

I generated a self-signed certificate and added it to the app:

This app will be used to call provide permissions, and to connect to the SharePoint front-end.

Users will register their applications in Azure, add Graph Sites.Selected and SharePoint Sites.Selected permissions, got tenant admin consent, then request permissions to the specific site by creating an intake request – new list item.

Front-End SharePoint Site

I created a SharePoint site for automation. This site will play a front-end role for users. I created a list “Sites.Selected” and updated list columns so I have the following fields:

  • Target Site Url
  • Application Id
  • Permissions (read/write)
  • Automation Output

In real-world (Prod) – You can (should) also implement approval workflow as you’d provide permissions for the application to the site only with this site owner approval. The PowerShell code behind should also validate site owner’s consent with app access to site. But for the sake of simplicity I’ll skip this in my demo.

Azure Function App

I created an Azure Function App with the following parameters:
– Runtime stack: PowerShell Core
– Version: 7.2.
– OS: Windows
– Hosting plan: Consumption

And then PowerShell timer-triggered function in Visual Studio Code.

Function requirements.psd1 (it takes a few hours for Azure to install modules; while modules are installing – you might see “[Warning] The first managed dependency download is in progress, function execution will continue when it’s done. Depending on the content of requirements.psd1, this can take a few minutes. Subsequent function executions will not block and updates will be performed in the background.”):

@{
    'Az' = '10.*'
    'PnP.PowerShell' = '2.*'
}

Azure Az module to access other Azure resources. PnP.PowerShell module will be used to access SharePoint.

I will keep my admin Azure registered app in a key vault, so need somehow to let the key vault know that this specific app can access this specific credentials. So I enabled system assigned managed Identity for the Function App:

MS: “This resource is registered with Azure Active Directory. The managed identity can be configured to allow access to other resources…”.
I’m going to use an object (principal) Id of this function to grant access to keyvault.

Azure key vault

Surely we do not hard-code app secrets. So we need a key vault o store app credentials.

I created a key vault under the same resource group in Azure and named it “SharePointAutomationDemo”. Then I added a roles assignment – “Key Vault Secret User” and “Key vault Reader” to the Function App via it’s managed identity:

I also assigned “Key Vault Administrator” role to the user (developer) who will add certificates/secrets to this key vault and develop Azure function code.

Your SharePoint tenant admin doesn’t allow site collection admins…

Scenario

You are trying to register an application at SharePoint site with appregnew.aspx page and you are getting an error or notification message “Your SharePoint tenant admin doesn’t allow site collection admins to create an Azure Access Control (ACS) principal“.

Your SharePoint tenant admin doesn't allow site collection admins to create an Azure Access Control (ACS) principal. Please contact your SharePoint tenant administrator

You are trying to provide ACS-based permissions for an application to SharePoint site with appinv.aspx page and you are getting “Your SharePoint tenant admin doesn’t allow site collection admins to update app permissions. Please contact your SharePoint administrator.

Your SharePoint tenant admin doesn't allow site collection admins to update app permissions. Please contact your SharePoint tenant administrator

Reason

This is due to a security measures enhancement MC660075 in Microsoft 365 tenant governance recently implemented by Microsoft. According to the update, only tenant administrators can create or update ACS service principal by default.

The root cause for this is that the Microsoft is pushing developers to Azure-registered applications with Sites.Selected API permissions as they are more secure that legacy ACS-based service principals.

Key differences ASC vs Sites.Selected are:

ACS-based SharePoint app/permissionsApps registered in Azure with Sites.Selected API permissions
support authentication with client secret only, secret is valid for 1 year exactlysupport authentication with client secret and certificate, custom expiration time
support granular access to SharePoint at the site-level e.g. to site collection or web or a specific listsupport only access to entire site collection (but Microsoft is working on granular access)
support only classic SharePoint REST API and CSOMsupport both – classic SharePoint REST API and CSOM and Microsoft Graph API
app id (client id) is created via appregnew.aspx at a specific SharePoint site by site collection administratorapp id (client id) is created in Azure portal, API Sites.Selected permissions are configured via Azure portal and require tenant admin consent
permissions for the app to a site are provided at the site by site collection administrator via appinv.aspx pagepermissions for the App to to a specific SharePoint site are provided by SharePoint admin with PowerShell script or Graph API calls

Solution

  1. Register an application in Azure (via Azure portal GUI, PowerShell script or your company’s specific helpdesk/servicedesk request)
  2. Update the app so both – MS Graph API Sites.Selected and SharePoint Sites.Selected permissions are configured and
  3. API permissions must be consented – so you’d seek/request your tenant admin consent
  4. Obtain and upload client certificate (recommended) or generate client secret
  5. Request access for the app to a specific SharePoint site (your SharePoint service admin should be able to do that)
  6. Validate your app has access to the target SharePoint site with PowerShell
  7. Secure your certificate and/or secret

If you are hosting your application in Azure – consider using managed identity.

Sites.Selected API permissions for SharePoint access

Sites.Selected permissions are needed for the non-interactive application to get access to a specific SharePoint site.

Steps to get access to SharePoint site with Sites.Selected:

1. Register an application in Azure (via Azure portal GUI, PowerShell script or helpdesk/servicedesk request)

2. Update the app so both – MS Graph API Sites.Selected and SharePoint Sites.Selected permissions are configured and consented by tenant admin

3. Obtain and upload client certificate (recommended) or generate client secret

4. Request access for the app to a specific SharePoint site (your SharePoint service admin should be able to do that via PowerShell script or Graph API calls )
Here is the Graph API

5. Validate your app has access to the target SharePoint site with PowerShell
tbp

6. Secure your certificate and/or secret

Consider using vault to keep certificate/secret. If you host your application in Azure – consider using managed identity

ACS-based permissions are going to be deprecated soon:
Your SharePoint admin doesn’t allow site owners to create/update ACS principal ⋆ Vladilen Microsoft 365 engineer

Token – SharePoint API compatibility matrix

If I get token with (Graph, MSAL, PnP) and use this token for (Graph API, SharePoint CSOM API, SharePoint REST API) matrix.

An App used in this tests has Sites.FullControl.All MS Graph API and SharePoint API permissions, as well as FullControl ACS based permissions to SharePoint (AppInv.aspx).

Token/APIMS Graph
/v1.0/sites
SharePoint CSOM
PnP.PowerShell
Get-PnPSite
Get-PnPTenantSite
SharePoint REST API
PnP.PowerShell
Invoke-PnPSPRestMethod
Invoke-RestMethod
MS Graph
/oauth2/v2.0/token
secret
OK(401) UnauthorizedAudienceUriValidationFailedException
MSAL.PS
Get-MsalToken
with secret
OK(401) UnauthorizedAudienceUriValidationFailedException
MSAL.PS
Get-MsalToken
with certificate
OK(401) UnauthorizedAudienceUriValidationFailedException
PnP.PowerShell
Get-PnPAccessToken
with Certificate
OKOK
OK
OK
AudienceUriValidationFailedException
PnP.PowerShell
Get-PnPGraphAccessToken
with Certificate
OKOK
OK
OK
AudienceUriValidationFailedException
PnP.PowerShell
Get-PnPAppAuthAccessToken
with Certificate or secret
InvalidAuthenticationTokenOK
OK
OK
OK
PnP.PowerShell
Request-PnPAccessToken
with Certificate
InvalidAuthenticationTokenOK
OK
OK
AudienceUriValidationFailedException
PnP.PowerShell
Request-PnPAccessToken
with Secret
InvalidAuthenticationTokenOK
OK
OK
OK
AudienceUriValidationFailedException = Exception of type ‘Microsoft.IdentityModel.Tokens.AudienceUriValidationFailedException’ was thrown

Testing Sites.Selected SharePoint and MS Graph API

Sites.Selected MS Graph API permissions were introduced by Microsoft in March 2021. One year later, in 2022 they added SharePoint Sites.Selected API permissions.

Azure registered app with SharePoint and MS Graph API Sites.Selected permissions

Why is this so important? Because MS Graph API for SharePoint is still limited and cannot cover all possible needs. I’d estimate: 90% of applications use SharePoint CSOM, so developers have to use AppInv.aspx to provide permissions for their applications to SharePoint API.

But from this moment – having SharePoint API permissions in MS Graph – in theory – we can fully rely on permissions provided in Azure and – in theory – this should allow us disable SharePoint-Apps only principal:

Set-SPOTenant -DisableCustomAppAuthentication $true

My math professor taught me: “before trying to find a solution – ensure the solution exists.” So let us test:

Are we really able to work with a specific SharePoint site using MS Graph and SharePoint API Sites.Selected permissions provided via Microsoft Azure?

What will happen with our new/legacy applications if we disable SharePoint app-only SPNs (DisableCustomAppAuthentication)?

I’m getting controversial test results… maybe PnP.PowerShell 1.10 is not fully support SharePoint Sites.Selected API.

Tech Wizard (Sukhija Vikas) on March 20, 2022 in the article “SharePoint and Graph API APP only permissions for Selected Sites” suggests using pre-release (AllowPrerelease).

So please ignore the following for a while.

Meantime I’ll test providing SharePoint Sites.Selected API permissions via Graph API call.

(wip) Test set #1: Certificate vs Secret

DisableCustomAppAuthentication: $false (SP-app-only spns are enabled).
All applications have “write” access provided to a specific site only.
Connecting with Connect-PnPOnline and then test access with Get-PnPSite

App / Get-PnPSiteSecretCertificate
ACS based (Azure+AppInv)OKThe remote server returned an error: (401) Unauthorized.
MS Graph API Sites.SelectedThe remote server returned an error: (403) Forbidden.The remote server returned an error: (401) Unauthorized.
SharePoint API Sites.SelectedOKOK
MS Graph API + SharePoint API Sites.SelectedAccess is denied. (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED))OK
App with no permissionsThe remote server returned an error: (403) ForbiddenThe remote server returned an error: (401) Unauthorized

(wip) Test set #2: Sites.Selected SharePoint vs MS Graph (secret)

  • DisableCustomAppAuthentication = $false
    (SP-app-only spns are enabled).
  • All applications have “write” access provided to a specific site only.
  • Using Client Secret (not a certificate)
  • Using PnP.PowerShell
Action/ViaSharePoint + MS Graph
Sites.Selected
“secret”
SharePoint
Sites.Selected
“secret”
MS Graph
Sites.Selected
“secret”
Connect-PnPOnlineWARNING: Connecting with Client Secret uses legacy authentication and provides limited functionality. We can for instance not execute requests towards the Microsoft Graph, which limits cmdlets related to Microsoft Teams, Microsoft Planner, Microsoft Flow and Microsoft 365 Groups.WARNING: Connecting with Client Secret uses legacy authentication and provides limited functionality. We can for instance not execute requests towards the Microsoft Graph, which limits cmdlets related to Microsoft Teams, Microsoft Planner, Microsoft Flow and Microsoft 365 Groups.WARNING: Connecting with Client Secret uses legacy authentication and provides limited functionality. We can for instance not execute requests towards the Microsoft Graph, which limits cmdlets related to Microsoft Teams, Microsoft Planner, Microsoft Flow and Microsoft 365 Groups.
Get-PnPSiteOKOKThe remote server returned an error: (403) Forbidden.
Get-PnPListOKOK
Get-PnPListItemOKOK
Set-PnPSiteAttempted to perform an unauthorized operation.
Set-PnPListAttempted to perform an unauthorized operation.
Set-PnPListItemOKOK
New-PnPListAccess is denied. (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED))
Add-PnPListItemOK

(wip) Test set #3: Read vs Write vs FullControl

DisableCustomAppAuthentication = $false
(SP-app-only spns are enabled).
All applications have Sites.Selected SharePoint and MS Graph API permissions.
Using Client Secret (not a certificate)
Using PnP.PowerShell

ReadWriteFullControl
Connect-PnPOnlineWARNING: Connecting with Client Secret uses legacy authentication and provides limited functionality. We can for instance not execute requests towards the Microsoft Graph, which limits cmdlets related to Microsoft Teams, Microsoft Planner, Microsoft Flow and Microsoft 365 Groups.WARNING: Connecting with Client Secret uses legacy authentication and provides limited functionality. We can for instance not execute requests towards the Microsoft Graph, which limits cmdlets related to Microsoft Teams, Microsoft Planner, Microsoft Flow and Microsoft 365 Groups.WARNING: Connecting with Client Secret uses legacy authentication and provides limited functionality. We can for instance not execute requests towards the Microsoft Graph, which limits cmdlets related to Microsoft Teams, Microsoft Planner, Microsoft Flow and Microsoft 365 Groups.
Get-PnPSiteAccess is denied. (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED))
Get-PnPListAccess is denied. (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED))
Get-PnPListItem
Set-PnPSite
Set-PnPList
Set-PnPListItem
New-PnPList
Add-PnPListItem

(wip) Test set #5: Certificate vs Secret

C#, SharePoint CSOM, PnP.Framework

Findings

PnP.PowerShell Get-, Grant-, Set- and Revoke-PnPAzureADAppSitePermission cmdlets require Azure App with MS Graph Sites.FullControl.All app permissions (otherwise it says “Access denied”) and authentication via certificate (otherwise it says “This cmdlet does not work with a ACS based connection towards SharePoint.”)

The same actions – managing permissions for the client app to the specific site collections – could be done via Microsoft Graph Sites Permissions API using just secret-based authentication.

If an azure app does not have Sites.Selected API permissions configured – “Grant-PnPAzureADAppSitePermission” works as expected – no error messages – the output is normal – as if Sites.Selected API permissions were configured in the app. The same for Get-, -Set and Revoke-. Permissions provided for the app to the site are not effective though: Connect-PnPOnline works well, but all other commands – starting from Get-PnPSite – returns “The remote server returned an error: (403) Forbidden.”

If an app have no permissions to SharePoint – “Connect-PnPOnline” works ok, but “Get-PnPSite” return an error: “The remote server returned an error: (403) Forbidden.”

Set-PnPAzureADAppSitePermission gives an error message “code”:”generalException”,”message”:”General exception while processing”
if the site is not specified.

AppInv is not working?

Error: Access is denied. (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED))

References

Testing environment

  • Microsoft 365 E5 Dev environment
  • PowerShell 7.2.2
  • PnP.PowerShell 1.10
  • “write” permissions to the specific sites for client apps were assigned via PnP.PowerShell

Providing Permissions to a Site for Sites.Selected App

How to provide permissions for an Azure registered application with MS Graph SharePoint Sites.Selected API permissions to a specific site via calling Microsoft Graph API from PowerShell.

We need an “admin” application – Azure registered application with with Sites.FullControl.All MS Graph API permissions. This method can use secret, so we need Client Id and Client Secret for this “admin” app.

We also need a Client Id and Application Display Name for an Azure application with Sites.Selected MS Graph and/or SharePoint API permissions provided.

And we need our “target” site Url.

With PowerShell scripts you can:

  1. Get Microsoft Graph Access Token with an “admin” app
  2. Get client (target) site Id
  3. Get current app permissions provided to client site
  4. Add read or write permissions for the client app to the client site
  5. Revoke one specific permission from site
  6. Revoke all app permissions provided to site

– please refer to the GitHub Repo Sites.Selected

References