Tutorial: Grant and revoke delegated permissions in Microsoft Entra ID

Artigo
06/13/2024

When you grant API permissions to a client app in Microsoft Entra ID, the permission grants are recorded as objects that can be accessed, updated, or deleted like other objects. Using Microsoft Graph PowerShell cmdlets to directly create permission grants is a programmatic alternative to interactive consent. This can be useful for automation scenarios, bulk management, or other custom operations in your organization.

Caution

Be Careful! Permissions created programmatically are not subject to review or confirmation. They take effect immediately.

In this tutorial, you'll grant and revoke delegated permissions that are exposed by an API to an app. Delegated permissions, also called scopes or OAuth2 permissions, allow an app to call an API on behalf of a signed-in user.

Prerequisites

To successfully complete this tutorial, make sure you have the required prerequisites:

A working Microsoft Entra tenant.
Microsoft Graph PowerShell SDK is installed. Follow the Install the Microsoft Graph PowerShell SDK guide to install the SDK.
Microsoft Graph PowerShell using a Privileged Role Administrator, Application Administrator, or a Cloud Application Administrator in the tenant and the appropriate permissions. For this tutorial, the Application.Read.All and DelegatedPermissionGrant.ReadWrite.All delegated permissions are required. To set the permissions in Microsoft Graph PowerShell, run:
```
Connect-MgGraph -Scopes "Application.ReadWrite.All", "DelegatedPermissionGrant.ReadWrite.All"
```

Caution

The DelegatedPermissionGrant.ReadWrite.All permission allows an app or a service to manage permission grants and elevate privileges for any app, user, or group in your organization. Only appropriate users should access apps that have been granted this permission.

Step 1: Get the delegated permissions of the resource service principal

Before you can grant delegated permissions, you must first identify the delegated permissions to grant and the resource service principal that exposes the delegated permissions. Delegated permissions are defined in the oauth2PermissionScopes object of a service principal.

In this article, you'll use the Microsoft Graph service principal in the tenant as your resource service principal.

Get-MgServicePrincipal -Filter "displayName eq 'Microsoft Graph'" -Property Oauth2PermissionScopes | Select -ExpandProperty Oauth2PermissionScopes | fl

AdminConsentDescription : Allows the app to read and write the full set of profile properties, reports, and managers of other users in your organization, on behalf of the signed-in user.
AdminConsentDisplayName : Read and write all users' full profiles
Id                      : 204e0828-b5ca-4ad8-b9f3-f32a958e7cc4
IsEnabled               : True
Origin                  :
Type                    : Admin
UserConsentDescription  : Allows the app to read and write the full set of profile properties, reports, and managers of other users in your organization, on your behalf.
UserConsentDisplayName  : Read and write all users' full profiles
Value                   : User.ReadWrite.All
AdditionalProperties    : {}

AdminConsentDescription : Allows the app to list groups, and to read their properties and all group memberships on behalf of the signed-in user.  Also allows the app to read calendar, conversations, files,
                          and other group content for all groups the signed-in user can access.
AdminConsentDisplayName : Read all groups
Id                      : 5f8c59db-677d-491f-a6b8-5f174b11ec1d
IsEnabled               : True
Origin                  :
Type                    : Admin
UserConsentDescription  : Allows the app to list groups, and to read their properties and all group memberships on your behalf.  Also allows the app to read calendar, conversations, files, and other group
                          content for all groups you can access.
UserConsentDisplayName  : Read all groups
Value                   : Group.Read.All
AdditionalProperties    : {}

Note

The output has been truncated for readability.

Step 2: Create a client service principal

The first step in granting consent is to create the service principal for the app that you'll grant permissions. To do so, you'll need the App Id of your application.

Register an application with Microsoft Entra ID

If the application isn't available, register an application with Microsoft Entra ID.

New-MgApplication -DisplayName 'My application' | 
  Format-List Id, DisplayName, AppId, SignInAudience, PublisherDomain

Id              : 40cbfad6-f138-4fb4-9e7f-5a44044efbd6
DisplayName     : My application
AppId           : 05210c44-437f-4a40-bd38-b5b4eaf251ef
SignInAudience  : AzureADandPersonalMicrosoftAccount
PublisherDomain : Contoso.com

Create a service principal for the application

New-MgServicePrincipal -AppId '05210c44-437f-4a40-bd38-b5b4eaf251ef' | 
  Format-List Id, DisplayName, AppId, SignInAudience

Id             : 22c1770d-30df-49e7-a763-f39d2ef9b369
DisplayName    : My application
AppId          : 05210c44-437f-4a40-bd38-b5b4eaf251ef
SignInAudience : AzureADandPersonalMicrosoftAccount

Step 3: Grant delegated permissions to the client enterprise application

To create a delegated permission grant, you'll need the following information:

ClientId - object ID of the client service principal to be authorized to act on behalf of the user. In this case, the service principal we created in step 2.
ConsentType - AllPrincipals to authorize all users in the tenant or Principal for a single user.
PrincipalId - Null for AllPrincipals consents or ID of the user for Principal consents.
ResourceId - object ID of the service principal representing the resource app in the tenant.
Scope - space-delimited list of permission claim values, for example User.Read.All.

In this example, the object ID of the resource service principal is 2cab1707-656d-40cc-8522-3178a184e03d. You'll grant the Group.Read.All scope to the service principal and grant consent on behalf of all users in the tenant.

$params = @{
  "ClientId" = "22c1770d-30df-49e7-a763-f39d2ef9b369"
  "ConsentType" = "AllPrincipals"
  "ResourceId" = "2cab1707-656d-40cc-8522-3178a184e03d"
  "Scope" = "Group.Read.All"
}

New-MgOauth2PermissionGrant -BodyParameter $params | 
  Format-List Id, ClientId, ConsentType, ExpiryTime, PrincipalId, ResourceId, Scope

Id          : DXfBIt8w50mnY_OdLvmzadDQeqbRp9tKjNm83QyGbTw
ClientId    : 22c1770d-30df-49e7-a763-f39d2ef9b369
ConsentType : AllPrincipals
PrincipalId :
ResourceId  : a67ad0d0-a7d1-4adb-8cd9-bcdd0c866d3c
Scope       : Group.Read.All

To confirm the delegated permissions assigned to the service principal on behalf of the user, you run the following command.

Get-MgOauth2PermissionGrant -Filter "clientId eq '22c1770d-30df-49e7-a763-f39d2ef9b369' and consentType eq 'AllPrincipals'"

ClientId             : 22c1770d-30df-49e7-a763-f39d2ef9b369
ConsentType          : AllPrincipals
Id                   : DXfBIt8w50mnY_OdLvmzadDQeqbRp9tKjNm83QyGbTw
PrincipalId          :
ResourceId           : 2cab1707-656d-40cc-8522-3178a184e03d
Scope                : Group.Read.All User.Read.All
AdditionalProperties : {}

Step 4: Grant more delegated permissions to the enterprise application

You can add more permissions to an existing oauth2PermissionGrant object.

To add the User.Read.All scope to the oauthPermissionGrant object, run:

$params = @{
  Scope = "Group.Read.All User.Read.All "
  }

Update-MgOauth2PermissionGrant -OAuth2PermissionGrantId 'DXfBIt8w50mnY_OdLvmzadDQeqbRp9tKjNm83QyGbTw' -BodyParameter $params

Step 5: Revoke delegated permissions granted to an enterprise application

If a service principal has been granted multiple delegated permission grants, you can choose to revoke either specific grants or all grants.

To revoke one or more grants, update oauthPermissionGrant object and specify only the delegated permissions to retain in the scope parameter. For example, to revoke the User.read.All permission, run:

$params = @{
  Scope = "Group.Read.All"
  }

Update-MgOauth2PermissionGrant -OAuth2PermissionGrantId 'DXfBIt8w50mnY_OdLvmzadDQeqbRp9tKjNm83QyGbTw' -BodyParameter $params

To revoke all grants, use Remove-MgOauth2PermissionGrant.

Remove-MgOauth2PermissionGrant -OAuth2PermissionGrantId 'DXfBIt8w50mnY_OdLvmzadDQeqbRp9tKjNm83QyGbTw'

When a delegated permission grant is deleted, the access it granted is revoked. Existing access tokens will continue to be valid for their lifetime, but new access tokens won't be granted for the delegated permissions identified in the deleted oAuth2PermissionGrant.

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