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.

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

Sites.Selected SharePoint API brief overview

Sites.Selected MS Graph API permissions were introduced by Microsoft in March 2021. It was a good move towards site-level access for non-interactive (daemon) applications, but still developers were limited with only what MS Graph API provides for SharePoint. SharePoint CSOM and REST API still provides much more than MS Graph API.

So developers had to use AppInv.aspx at site level to provide ACS-based permissions to their apps to be able to use SharePoint CSOM and REST APIs. The bad news is ACS-based permissions have some downsides so some SharePoint/m365/security engineers consider them legacy and deprecated. But if we decide to disable SharePoint App-only service principals – all apps with ACS-based permissions provided via AppInv.aspx will stop working.

2021: Microsoft Graph Sites.Selected API

Microsoft Graph Sites.Selected API

Recently Microsoft introduced Sites.Selected SharePoint API permissions for registered Azure Apps! So from now developers should be fully happy with API permissions provided in Azure (without SharePoint ACS-based permissions).

2022: SharePoint Sites.Selected API

SharePoint Sites.Selected API

Why is this so important? Because this should allow us to be able to switch from ACS based permissions provided in SharePoint via AppInv.aspx to Azure-provided permissions and as a consequence – disable SharePoint-Apps only principal (‘set-spotenant -DisableCustomAppAuthentication $true’).

Why we are eager to disable Custom App Authentication in SharePoint? Simply say, SharePoint App-only service principals are not trackable (they all appeared as a “spo_service@support.onmicrosoft.com” id in all logs) and hard to manage (there is no way to get list of existing/registered SP app-only service principals, sites and their owners) – see more in this article.

So, SharePoint Sites.Selected application API permissions provided in Azure is a significant step to make Microsoft 365 SharePoint environment more secure and manageable.

2024: Delegated Sites.Selected Permissions

Since Feb 2024 Microsoft supports also delegated Sites.Selected permissions. Delegated Sites.Selected permissions are assigned the same way as application Sites.selected permissions – through the /permissions endpoint. You still assign only the application id and role. When the call is made the permissions are calculated either as application or delegated, and assuming the request is authorized it will go through.

2024: Granular Sites.Selected Application Permissions

Microsoft implemented granular permissions ( e.g. to a list, item or file) alongside with Sites.Selected permissions. Original implementations of Sites.Selected allowed access to entire site collection only. With new ‘Lists.SelectedOperations.Selected’, ‘ListItems.SelectedOperations.Selected’ and ‘Files.SelectedOperations.Selected’ permissions it is possible to provide application permissions to list, library or list item or particular document (reference).

Details To Be Provided…

Delegated Sites.Selected API permissions

Since the beginning of 2024 Microsoft supports Delegated Sites.Selected API permissions. This is to support security best practices – the minimally possible access should be provided. I.e. the idea is: even Sites.FullControl.All delegated permissions allows access not to all sites, but to sites current user was provided access to, it would be a good idea to restrict access with only sites this specific app is required access to. That’s good.

More on the Sites.Selected:

References

Connecting to SharePoint Online programmatically: Secret vs Certificate

Update: Sites.Selected API MS Graph permissions was introduced by Microsoft in 2021. It was a good move towards site-level development, but still developers were limited with only what MS Graph API provides for SharePoint dev.
So devs had to use AppInv.aspx at site level to provide ACS permissions to their apps to be able to use SharePoint CSOM and REST APIs.
Recently Microsoft introduced Sites.Selected SharePoint API permissions for registered Azure Apps! So now devs should be fully happy without ACS-based permissions.

Scenario

You have an application that needs access to Microsoft 365 SharePoint Online site/list/documents. Application is running without interaction with users – e.g. unattended, as daemon job.

There are two options you can authenticate to Microsoft 365 – with the secret or with the certificate. Authenticating with certificate is considered more secure.

Questions

  • What happens if SharePoint-Apps only principal is disabled
    (i.e. ‘set-spotenant -DisableCustomAppAuthentication $true’ )?
  • Why I’m getting 401 error when authenticating to SPO?
  • Why I’m getting 403 error when authenticating to SPO with secret?
  • What permissions to I need to work with SPO?

Findings

Note: we will use PowerShell 7.2 and PnP.PowerShell 1.9 to illustrate it.

Disabled SharePoint-Apps only principal

If SharePoint-Apps only principal is disabled in your tenant
(i.e. ‘Get-PnPTenant | select DisableCustomAppAuthentication’ returns $true ), then the only way you work with SPO from code is:

  • an App registered in Azure
  • API permissions provided via Azure (MS Graph, SharePoint)
  • Certificate is used

In all other cases (even your Connect-PnPOnline command complete successfully) – you will be getting error 401 (unauthorized) when trying Get-PnPTenant or Get-PnPTenantSite or Get-PnPSite

Enabled SharePoint-Apps only principal

If SharePoint-Apps only principals are enabled in your tenant
(i.e. ‘Get-PnPTenant | select DisableCustomAppAuthentication’ returns $false ), then you have three options to work with SPO from code:

  • Azure App with a secret (Client Id + Client Secret) and permissions to SharePoint provided via SharePoint (AppInv.aspx) to access SharePoint REST API
  • Azure App with a certificate (Client Id + Certificate) and permissions provided via Azure to access SharePoint REST API
  • Azure App with a certificate or secret (Client Id + Secret or Certificate) and permissions provided via Azure to access SharePoint via Microsoft Graph API

Track SharePoint App-only Service Principals in Microsoft 365

Update (May 2023):
You can use Get-PnPAzureACSPrincipal to returns the lists of all Azure ACS principals installed in your Tenant including subsites.

Scenario

Developers in the organization can use both – Azure Apps and SharePoint Apps to work with SharePoint sites in their “daemon” applications.

It is recommended to use Azure apps so, you want to know – what are SharePoint Apps registered and their owners, who registered SharePoint Apps. Eventually you would disable SharePoint Apps-only principal but before that you’d move Devs from SP-App-only to Azure App (see Disable Custom App Authentication).

(SharePoint App-only service principals aka SP-App-Only are SPN or App registered from within SharePoint using AppRegNew.aspx system page).

One of the approaches is to track Apps/Owners with Unified Audit Log

Use Unified Audit Logs

The following PowerShell code:

$operations = 'Add service principal.'
$recordType = 'AzureActiveDirectory'
Search-UnifiedAuditLog -StartDate $start -EndDate $end -ResultSize $resultSize -Formatted -Operations $operations -RecordType $recordType

returns events with operation = ‘Add service principal.’ Nice, but…
if an app was registered in Azure – event contains an UPN under UserIds property:

Unfortunately, in case with registering app in SharePoint, an audit log event will be like:

i.e. UserId registerd is “spo_service@support.onmicrosoft.com”, so we do not know who registered a SharePoint-only app

In theory – we could use events recorded immediately before and after “Add service principal” event to track a user and site who has registered a SharePoint-only app… But for me it seems like too complicated for automation.

Instead we can do simple search through audit log for events “AppRegNew.aspx page visited”. This gives us a good approximation of who registered SP-App-only principal. Worst scenario – we reach more people than we really need (including those who started registering sp-app-only but did not complete) but all of them would be definitely our target auditory.

Consider the following code:

$freeText = "appregnew"
$operations = 'PageViewed'
$recordType = 'SharePoint'

$results = Search-UnifiedAuditLog -StartDate $start -EndDate $end -ResultSize $resultSize -FreeText $freeText -Operations $operations -RecordType $recordType 

this would give you all users who loaded “/_layouts/15/appregnew.aspx” page

Update: Sites.Selected API MS Graph permissions was introduced by Microsoft in 2021. It was a good move towards site-level development, but still developers were limited with only what MS Graph API provides for SharePoint dev.
So devs had to use AppInv.aspx at site level to provide ACS permissions to their apps to be able to use SharePoint CSOM and REST APIs.
Recently Microsoft introduced Sites.Selected SharePoint API permissions for registered Azure Apps! So now devs should be fully happy without ACS-based permissions.

References

Access SPO Site Programmatically via MS Graph API and SharePoint API

Scenario

You are a software developer. Your company uses Microsoft Office 365 (SharePoint, Teams etc.). The need is to work with a specific site collection programmatically (from code – Python, C#, Java, PowerShell, JavaScript etc.) – e.g. upload/download documents, update list items, search etc.

The code must run without user interaction (unattended, aka daemon app). Sometimes this is also called “SharePoint Automation”.

The solution is based on a new Graph API feature – Sites.Selected and a classic SP-Only app.

Solution

  1. Register an Azure App and configure it as usual.
    Select API Permissions blade and add two permissions:
    – Microsoft Graph -> Applications Permissions -> “sites.selected
    – SharePoint -> Applications Permissions -> “sites.selected
  2. Request “Grant admin consent” from a tenant/global admin
  3. Request SharePoint admin to run PowerShell code (e.g. this one) to assign proper permissions to your azure app for a specific site collection (consider site owner consent)
  4. (optionally) Provide SharePoint API permissions:
    (require Site Collection Owner/Admin account) – use
    https://YourTenant.sharepoint.com/teams/YourSite/_layouts/15/appinv.aspx
    to add SharePoint API permissions to your app. E.g. full control permissions to site collection would be
<AppPermissionRequests AllowAppOnlyPolicy="true">  
   <AppPermissionRequest Scope="http://sharepoint/content/sitecollection" 
    Right="FullControl" />
</AppPermissionRequests>

Consider minimal permissions (e.g. Right=”Read” see more with Sumit)

Problem Solved

  • you get access to one and only one site collection (“least privilege” principal)
  • you get both – SharePoint API and Microsoft Graph API permissions to SharePoint
  • you can use app secret or certificate to authenticate – depending on what are your security requirements

Note: if your scenario require authenticated user present – the solution would be a little different: Connect-PnPOnline Interactive with Client App Id

Update:

Sites.Selected API MS Graph permissions was introduced by Microsoft in 2021. It was a huge step forward, but still devs were limited with MS Graph API against SharePoint.
So devs had to use AppInv at site level to provide ACS permissions to their apps to use SharePoint CSOM and REST APIs.
Recently Microsoft introduced Sites.Selected SharePoint API permissions for registered Azure Apps! So now devs should be fully happy without ACS-based permissions AppInv.aspx. (See more here on disabling SP Apps Only SPNs)

Thanks to Leon Armston and Scott Murdock

Update 2:

Microsoft announced end-of-life for ACS permissions, so we’d need to avoid ACS permissions for new development.

References: