Protección de la entrega de WebHooks con la aplicación Microsoft Entra en Azure Event Grid

Este script proporciona la configuración para entregar eventos a puntos de conexión HTTPS protegidos por Microsoft Entra Application usando Azure Event Grid.

Estos son los pasos generales del script:

1. Cree una entidad de servicio para Microsoft.EventGrid si todavía no existe.
2. Cree un rol llamado AzureEventGridSecureWebhookSubscriber en la aplicación Microsoft Entra para su Webhook.
3. Cree una entidad de servicio para la aplicación de escritura de suscripciones de eventos si todavía no existe.
4. Agregar el servicio principal del escritor de suscripciones a eventos de la aplicación Microsoft Entra al rol AzureEventGridSecureWebhookSubscriber
5. Agregue también la entidad de servicio de Microsoft.EventGrid al rol AzureEventGridSecureWebhookSubscriber.

Script de ejemplo: estable

# NOTE: Before run this script ensure you are logged in Azure by using "az login" command.

$webhookAppObjectId = "[REPLACE_WITH_YOUR_ID]"
$eventSubscriptionWriterAppId = "[REPLACE_WITH_YOUR_ID]"

# Start execution
try {

    # Creates an application role of given name and description

    Function CreateAppRole([string] $Name, [string] $Description)
    {
        $appRole = New-Object Microsoft.Graph.PowerShell.Models.MicrosoftGraphAppRole
        $appRole.AllowedMemberTypes = New-Object System.Collections.Generic.List[string]
        $appRole.AllowedMemberTypes += "Application";
        $appRole.AllowedMemberTypes += "User";
        $appRole.DisplayName = $Name
        $appRole.Id = New-Guid
        $appRole.IsEnabled = $true
        $appRole.Description = $Description
        $appRole.Value = $Name;

        return $appRole
    }

    # Creates Azure Event Grid Microsoft Entra Application if not exists
    # You don't need to modify this id
    # But Azure Event Grid Entra Application Id is different for different clouds

    $eventGridAppId = "4962773b-9cdb-44cf-a8bf-237846a00ab7" # Azure Public Cloud
    # $eventGridAppId = "54316b56-3481-47f9-8f30-0300f5542a7b" # Azure Government Cloud
    $eventGridSP = Get-MgServicePrincipal -Filter ("appId eq '" + $eventGridAppId + "'")
    if ($eventGridSP.DisplayName -match "Microsoft.EventGrid")
    {
        Write-Host "The Event Grid Microsoft Entra Application is already defined.`n"
    } else {
        Write-Host "Creating the Azure Event Grid Microsoft Entra Application"
        $eventGridSP = New-MgServicePrincipal -AppId $eventGridAppId
    }

    # Creates the Azure app role for the webhook Microsoft Entra application
    $eventGridRoleName = "AzureEventGridSecureWebhookSubscriber" # You don't need to modify this role name
    $app = Get-MgApplication -ObjectId $webhookAppObjectId
    $appRoles = $app.AppRoles

    Write-Host "Microsoft Entra App roles before addition of the new role..."
    Write-Host $appRoles.DisplayName
    
    if ($appRoles.DisplayName -match $eventGridRoleName)
    {
        Write-Host "The Azure Event Grid role is already defined.`n"
    } else {      
        Write-Host "Creating the Azure Event Grid role in Microsoft Entra Application: " $webhookAppObjectId
        $newRole = CreateAppRole -Name $eventGridRoleName -Description "Azure Event Grid Role"
        $appRoles += $newRole
        Update-MgApplication -ApplicationId $webhookAppObjectId -AppRoles $appRoles
    }

    Write-Host "Microsoft Entra App roles after addition of the new role..."
    Write-Host $appRoles.DisplayName

    # Creates the user role assignment for the app that will create event subscription

    $servicePrincipal = Get-MgServicePrincipal -Filter ("appId eq '" + $app.AppId + "'")
    $eventSubscriptionWriterSP = Get-MgServicePrincipal -Filter ("appId eq '" + $eventSubscriptionWriterAppId + "'")

    if ($null -eq $eventSubscriptionWriterSP)
    {
        Write-Host "Create new Microsoft Entra Application"
        $eventSubscriptionWriterSP = New-MgServicePrincipal -AppId $eventSubscriptionWriterAppId
    }

    try
    {
        Write-Host "Creating the Microsoft Entra Application role assignment: " $eventSubscriptionWriterAppId
        $eventGridAppRole = $app.AppRoles | Where-Object -Property "DisplayName" -eq -Value $eventGridRoleName
        New-MgServicePrincipalAppRoleAssignment -ServicePrincipalId $eventSubscriptionWriterSP.Id -PrincipalId $eventSubscriptionWriterSP.Id -ResourceId $servicePrincipal.Id -AppRoleId $eventGridAppRole.Id 
    }
    catch
    {
        if( $_.Exception.Message -like '*Permission being assigned already exists on the object*')
        {
            Write-Host "The Microsoft Entra Application role is already defined.`n"
        }
        else
        {
            Write-Error $_.Exception.Message
        }
        Break
    }

    # Creates the service app role assignment for Event Grid Microsoft Entra Application

    $eventGridAppRole = $app.AppRoles | Where-Object -Property "DisplayName" -eq -Value $eventGridRoleName
    New-MgServicePrincipalAppRoleAssignment -ServicePrincipalId $eventGridSP.Id -PrincipalId $eventGridSP.Id -ResourceId $servicePrincipal.Id -AppRoleId $eventGridAppRole.Id 
    
    # Print output references for backup

    Write-Host ">> Webhook's Microsoft Entra Application Id: $($app.AppId)"
    Write-Host ">> Webhook's Microsoft Entra Application ObjectId Id: $($app.ObjectId)"
}
catch {
  Write-Host ">> Exception:"
  Write-Host $_
  Write-Host ">> StackTrace:"  
  Write-Host $_.ScriptStackTrace
}

Explicación del script

Para más información, consulte Entrega segura de WebHook con Microsoft Entra ID en Azure Event Grid.