Steve Spencer's Blog

Blogging on Azure Stuff

Testing connectivity to your backend service with Hybrid Connection in App Service

I have a backend service that is connected to my web site which is hosted in Azure App Service using a Hybrid Connection. When setting up a Hybrid Connection it is useful to be able to test connectivity to your backend service. I’ve previously posted a video to show you to access the Kudu control panel so that you can look at the files in the hosted site. We’ll use the Kudu control panel to also test connectivity, only this time we’ll use the PowerShell debug console.

In Azure Portal click on your app service and go to Advanced Tools and select Go

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This will open the Kudu console in a new tab.

Click on Debug console the PowerShell

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This opens the debug console in PowerShell and allows your to run PowerShell commands on the App Service. As you are running on the App Service you will have access to the backend service that is connected via the web service.

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My service has a Get endpoint that I can call to test connectivity. There are a number of commands we could run but I’ll use Invoke-WebRequest.

For this I am using www.bing.com but you use the url of your backend service that you have configured in your Hybrid Connection.

Invoke-WebRequest -Uri http://www.bing.com

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This returns the following error

The response content cannot be parsed because the Internet Explorer engine is not available, or Internet Explorer's first-launch configuration is not complete. Specify the UseBasicParsing parameter and try again.

The error says what you need to do. Add UseBasicParsing to the command

Invoke-WebRequest -Uri http://www.bing.com –UseBasicParsing

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We now get the error:

Win32 internal error "The handle is invalid" 0x6 occurred while reading the console output buffer

To fix this we need to tell PowerShell to silently continue by issuing the following command:

$progressPreference = "silentlyContinue"

Then call your web request

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I’ve now got the output from the web request with a status code of 200 showing I’ve got connectivity.

Using Graph API to automate Azure AD

In my previous posts I discussed how you can manage access to applications (part 1) using Azure AD and also how you can add users users from outside of your organisation (part 2). Now we will look at how you can automate this using Graph API.

“The Microsoft Graph API offers a single endpoint, https://graph.microsoft.com, to provide access to rich, people-centric data and insights exposed as resources of Microsoft 365 services. You can use REST APIs or SDKs to access the endpoint and build apps that support scenarios spanning across productivity, collaboration, education, security, identity, access, device management, and much more.” - https://docs.microsoft.com/en-us/graph/overview

From the overview you can see that Graph API covers a large area of Microsoft 365 services. One of the services it covers is Azure AD. What I’ll show you today is how to invite users and then add/remove them to/from groups using Graph API.

There are two ways to access Graph API. A user centric approach (Delegated) that requires a user account and an application centric approach that uses an application key and secret. Accessing Azure AD for user invite and group management utilises the application centric approach. In order to get an application id and secret you will need to create an application in Azure AD. The first post in the series talks about how to create an App Registration.

Once you have created your application, there are a couple of bits of information you require in order to get started. These are the tenantId and clientId. These can be found in the Azure portal. Navigate to your App Registration and the details can be found in the Overview blade.

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If you hover over each of the Guids a copy icon appears to allow you to easily copy these values.

Next you will need a key generating. For this you click on the Certificates and secrets blade.

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Then click “New client secret” and populate the form and click “Add”

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Your key will now appear.

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Make sure you copy this as it is not visible again once you navigate away and you will need to generate a new one.

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We are now ready to start looking at Graph API. There is good documentation about each of the functions in Graph API including the permissions required to access and code samples in a variety of languages. If we look at the list User function:

https://docs.microsoft.com/en-us/graph/api/user-list?view=graph-rest-1.0&tabs=http

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You can see the permissions needed to access this function. As we are using an Application permission type we need to set one of the permissions: User.Read.All, User.ReadWrite.All, Directory.Read.All or Directory.ReadWrite.All.

You can set the permissions required by going to your App Registration and clicking on the “API permissions”

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The application by default requires a user login that can read their own user profile. We need to add some additional permissions to allow our application to list the users in AD.Click on “Add permission”

This shows the list of built-in API’s that you can access. We are only looking at Microsoft Graph today

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Click “Microsoft graph”

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Then “Application permission” and scroll to the User section

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To list users we need the User.Read.All permission, but we’ll also add the User.Invite.All so that we can invite B2B users. click “Add permissions”.

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Although you have added the permissions you cannot currently access the Graph API as you will need to Grant admin consent in first. If we had  added a Delegated permission then the user could try an access the Graph API but Admin consent would be required to stop anyone from accessing certain features. This can be done in a workflow with selected Admins being notified of access. Before the use can access an Administrator would need to approve each access. This process will not work for our application as it is an unattended application using the application permission type. We can however grant access to this application user by clicking “Grant admin consent …” button and clicking Yes to the message box that pops up.

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Clicking the button adds admin consent to all permissions. If you want to remove it from any, click the ellipsis (…) at the end and click “Revoke admin consent”

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You can also remove permissions from this menu.

Your user is now ready to go. I’m using the C# SDK and this is available as a nuget package

Once the nuget package is installed. You will need to create an instance of the Graph API client:

ConfidentialClientApplicationOptions _applicationOptions = new ConfidentialClientApplicationOptions
{
     ClientId = ConfigurationManager.AppSettings["ClientId"],
     TenantId = ConfigurationManager.AppSettings["TenantId"],
     ClientSecret = ConfigurationManager.AppSettings["AppSecret"]
};


// Build a client application.
IConfidentialClientApplication confidentialClientApplication = ConfidentialClientApplicationBuilder
                 .CreateWithApplicationOptions(_applicationOptions)
             .Build();


// Create an authentication provider by passing in a client application and graph scopes.
ClientCredentialProvider authProvider = new ClientCredentialProvider(confidentialClientApplication);


// Create a new instance of GraphServiceClient with the authentication provider.
GraphServiceClient graphClient = new GraphServiceClient(authProvider);

You will need the ClientId, TenentId and Secret you copied earlier. Looking at the Graph API documentation there are example of how to use each of the functions.

image

We want to see if a user existing in our AAD before we invite them, so we will use the filter option as above.

var user = (await graphClient.Users
                 .Request(options)
                 .Filter($"mail eq '{testUserEmail}'")
                 .GetAsync()).FirstOrDefault();

Console.WriteLine($"{testUserEmail} {user != null} {user?.Id} [{user?.DisplayName}] [{user?.Mail}]");

If user is null then is does not exist in your AzureAD tenant. Assuming that this is an external user then you will need to invite the user to be able to access your application. I created a method for this:

private async Task<Invitation> InviteUser(IGraphServiceClient graphClient, string displayName, string emailAddress, string redirectUrl, bool wantCustomEmaiMessage, string emailMessage)
{
     // Needs: User.InviteAll

    var invite = await graphClient.Invitations
                     .Request().AddAsync(new Invitation
                     {
                         InvitedUserDisplayName = displayName,
                         InvitedUserEmailAddress = emailAddress,
                         SendInvitationMessage = wantCustomEmaiMessage,
                         InviteRedirectUrl = redirectUrl,
                         InvitedUserMessageInfo = wantCustomEmaiMessage ? new InvitedUserMessageInfo
                         {
                             CustomizedMessageBody = emailMessage,
                         } : null
                     });

    return invite;
}

Now you’ve just invited a B2B user into your Azure AD tenant. At the moment they do not have access to anything as you’ve not assigned them to any application. The Graph API for assigning users to applications uses the delegated permissions model which means you need to use an actual user account. The Graph API with the application permission model does not support adding users to applications. In order to use the same application client you used for inviting users, you could assign a group to your application and then use the Graph API to add/remove users to/from that group.

Adding/removing a user to/from a group requires one of the following permissions: GroupMember.ReadWrite.All, Group.ReadWrite.All and Directory.ReadWrite.All. This is set in the same way as for the user permissions in the App Registration/Api permission section mentioned earlier. Admin consent will also need to be granted for these permissions.

The code to add & remove users is below:

// find group
var groupFound = (await graphClient.Groups
                                         .Request()
                                         .Filter($"displayName eq '{groupName}'")
                                         .Expand("members")
                                         .GetAsync()).FirstOrDefault();

Console.WriteLine($"{groupName} {groupFound != null } [{groupFound?.Id}] [{groupFound?.DisplayName}] [{groupFound?.Members?.Count}]");

if (groupFound != null)
{
     // check is the user is already in the group
     var user = (from u in groupFound.Members
                 where u.Id == user.Id
                 select u).FirstOrDefault();
     Console.WriteLine($"user Found {user != null}");

    if (user != null)
     {
         Console.WriteLine($"removing user {user.Id}");
         // remove from group
         await graphClient.Groups[groupFound.Id].Members[user.Id].Reference
                                     .Request()
                                     .DeleteAsync();

    }
     else
     {
         Console.WriteLine($"adding user {user.Id}");
         // add to group
         await graphClient.Groups[groupFound.Id].Members.References
             .Request()
             .AddAsync(new DirectoryObject
             {
                 Id = user.Id
             });
     }
}

In the code above I wanted the Graph API to return me the list of users in the group. By default you do not see this data when retrieving group information. Adding the Expand method tells Graph API to extend the query and return the additional data. This is something to bear in mind when using Graph API. Just because the data is null does not mean that there is no data, you might need to expand the data set returned.

I hope you found this a useful introduction to Graph API, I will be posting more on Azure AD in the future including more on Graph API.

Managing Application Access with Azure AD–Part 2

In my previous post I showed you how to set up an application in Azure AD and allow Azure AD users to access it. In this post I will show how you can give access to these applications to users outside of your organisation using B2B (Business to Business) as guest users.

B2B is a feature of Azure AD that allows you to easily add two types of user to your applications.

  1. Users who are part of another Azure AD tenant
  2. Users who are not.

If your new user is part of another Azure AD tenant, then when we add them as a guest user to you application and they will use the credentials provided by their own organisation. This means they do not have to remember a new username and password when they want to access your application. It is also useful as they will be managed by their own organisation so you will not be responsible for resetting their passwords for example. Another advantage of using their own Azure AD credentials is that they will lose the ability to sign in to your application when their accounts are disabled or removed from your customer’s tenant. They will however still exist as a guest user in your application but they will no longer be able to sign in.

If your new user is not part of another Azure AD tenant, then they will automatically have a Microsoft account created for them. They will also be prompted to enter a new password. Again this is not managed by you but by Microsoft this time, so password resets are handled by a link provided by them.

To assign a guest user to your application you will need to invited them to use your application. They will then receive an invitation via email that they will need to redeem in order to access your application.

So, go back to the Azure AD blade of the Azure portal and click on Users:

Home ) Default Directory > Users All users 
a 
Users I All users 
Default Direct'bqj - Azure Active Director,' 
All users 
Deleted users 
Password reset 
+ New guest user 
New user 
Search users 
Name 
T Bulk create Bulk invite 
Add filters 
user name 
Bulk delete 
Download users 
user type 
Refresh 
p Reset passwo 
Source

The click on “New guest user”

Home > Default Directory > Users I All users > New user 
New user 
Default 
C) Got feedback? 
o 
Create user 
Create a new user in your organization. 
This user will have a user name like 
alice@sdspencergmail.onmicrosoft.com. 
I want to create users in bulk 
Invite user 
Invite a new guest user to collaborate With 
your organization. The user will be emailed 
an invitation they can accept in order to 
begin collaborating. 
I want to invite guest users in bulk 
Help me decide 
Identity 
Name C) 
Email address* @ 
First name 
Last name 
Personal message 
Invite 
Example: •Chris Green' 
xample: chris@contoso.com

Fill in the form and enter your own personal message and click  “Invite”. You need to enter a valid email address otherwise the user will not be able to receive the invite, as seen below:

image

The text highlighted inside the red box was the custom message I entered in the invitation process. It is possible to change the branding of this email but it is an Azure AD premium feature.

The invite process proves that the user has access to the mail box linked to the email address used. Also, if they are using their organisations Azure AD email address then they must also sign in with their own username an password so you can be confident that they user is who they say they are. This example shows the flow when a user is part of another Azure AD tenant. If the user is not part of another tenant then there will be additional screens for setting up their new Microsoft account and password.

When the user clicks the Accept invitation link they will be redirected to a consent page which is asking for permissions to read their user profile from their Azure AD tenant.

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Accepting the permissions then will redirect the user to the application portal where the user can access the applications they have been assigned. As we have not allocated any applications to this user yet, they will not see anything,

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To assign applications to the users, go back to the Azure AD blade in teh Azure portal and click on Users then click on the one you have just added to view their profile:

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You can see, in this example, in the red box that this is a Guest user who has accepted the invitation.

Click on applications in the left hand menu bar you will see that there are none assigned. To assign this user to an application, navigate back to the Azure AD main blade and click Enterprise applications, then select the application you wish to assign this user to.

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Click “Assign users and groups”, then Add User

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Click “None Selected” then search for your new user, select them and click Select.

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Now click Assign

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The new users is now assigned. Go back to the  Application screen the user viewed after they signed in and refresh the page

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The assigned application should now be visible and clicking the application will redirect the user to that applications web site.

Using Azure AD it is easy to now invite users to user your applications and when they are part of another Azure AD tenant, Azure AD takes all the pain out of federating with these new users tenants. Hopefully you have found that this is straight forward and this will have opened up access to your applications in a controlled way. My next post will look at how we can automate this using Graph API.

Introduction to Azure Role Based Access Control (RBAC)

Up until fairly recently I have been managing  access to a number of Azure subscriptions but as I’ve been working for smaller organisations the number of people who needed access was fairly small and easy to manage. It also meant that I generally gave the users Owner or Contributor access to the subscriptions as we were all managing everything so we needed the access at that level. Now I work for a large organisation there is a greater need to  limit access to certain areas of Azure and giving subscription wide access is limited to a few key administrators. This means that I need to look at the minimum access that is required for each of the users who need access to the resources. First I’d like to talk about the scope within which permissions can be set within Azure. For most of the scenarios I’ve worked in I have visibility of a single subscription. For organisations  with a large number of subscriptions there is a further level of scope, Management group, which I won’t be discussing.

image

Permissions can be set at the Subscription, Resource group or the individual resource scope.Depending upon the level of access your user requires there are three basic levels which you can use

  • Owner
  • Contributor
  • Reader

Owner gives the user full access to everything within the scope and can also assign roles to other users.

Contributor gives the user full access to everything within the scope except they are not able to assign roles to other users

Reader give the user access to view the resources within the scope but they are not able to change anything or assign roles.

So assigning the user the Owner role at the Subscription level, then the user can manage all resources within the subscription and assign roles to users. A user can be assigned multiple roles and Azure RBAC is additive so if a user was assigned Contributor at the subscription scope but only Reader on one of the resource groups, the Contributor role would override the reader role. It is also possible to have Deny role assignments. Where a user is Denied permissions on a specific role. Deny assignments take precedence over role assignments.

These roles plus the variety of scopes give some flexibility of access but it is still a large surface area of access that is provided. Azure offers a large number of finer grained roles to allow users to be given specific permissions to specific services. There are a large number of built in assignments as can be seen here: https://docs.microsoft.com/en-us/azure/role-based-access-control/built-in-roles

These finer grained roles allow you to set specific permissions on a specific user within a specific scope. For example if  you wanted to give a user access to a blob store to upload files via the Azure portal there are two permissions that can be set: Reader and Data Access and

Storage Blob Data Contributor. If you assign these two roles to a user in the storage account, then the user is able to login to the Azure portal and navigate to the storage account and access the blob store.

To do this, navigate to the storage account within which you want to assign a role and click the access control item

image

The click “Add role assignment”

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In the role drop down pick “Storage Blob Data Contributor”, select the user you want to assign the role to and click save. Repeat this for the Reader and Data Access role. Your user now has access only to blob storage and has no access elsewhere in the resource group or subscription. I could have done the same thing by selecting the resource group and Access control and adding these roles there. This would have give the user access to all blob stores within the resource group.

Another example is that you may want to give someone access to your app service so that they can configure and deploy. So navigate to your App Service and click “Access control”, then select the role “Website Contributor”. See https://docs.microsoft.com/en-us/azure/role-based-access-control/built-in-roles#website-contributor for more details. This lets you manage the selected website but not app service plans and no other web sites. If you want to manage other app services then you could add the same role at the resource group level.

Managing Application Access with Azure AD – Part 1

In my next series of blog post I want to talk about how to manage access to applications using Azure AD.

I’ve been looking at how I can set up access to my web based applications and I want to be able to:

  1. Have a single sign on with multiple applications
  2. Allow some users access to only some of the applications
  3. Be able to give access to users outside of my organisation
  4. Be able to control access via code

Part 1 will cover setting my applications up and then restricting access to the applications via Azure AD.

In order to test this I needed to have a number of applications that I could use. I used this example:

https://github.com/AzureADQuickStarts/AppModelv2-WebApp-OpenIDConnect-DotNet

It allows me to login and see my claims. I deployed this into two different app services so I could navigate to them separately. I’m not going to talk about the code on the web side apart from the bits you need to configure up the sample. This series of blogs are more about how to setup Azure AD and the path I went through to my end goal of configuring up users programmatically.

In order to integrate with Azure AD we need to set up each of the applications. This will provide us with an ID with which we can  use to configure each of the applications.

In Azure Portal navigate to Azure Active Directory, or search for it in the search bar

C portal-azure.com/#home 
Microsoft Azure 
p Search resources, services, and docs (G./) 
Azure services 
Create a 
resource 
Azure Active 
Directory 
SQL databases 
Azure AD 
Privileged. 
App 
registrations    C portal-azure.com/#home 
p activd 
Microsoft Azure 
Services 
Azure s 
Azure AD Privileged Identity Management 
-+ Activity log 
Azure Active Directory 
reso HDlnsight clusters 
e Monitor

Home > Default Directory I Overview 
O Default Directory I Overviev 
Azure Active Directory 
p Search (Ctrl 4/) 
O Overview 
Getting started 
Diagnose and solve problems 
Manage 
users 
Organizational relationships 
Roles and administrators 
Enterprise applications 
Devices 
App registrations 
Identity Governance    Home > Default Directory App registrations 
Default Directory I App registrations 
Active 
Search (Ctrl *

In the menu bar on the left select App Registrations –> New registration and complete the form:

Home ) Default Directory App registrations ) Register an application 
Register an application 
-k Name 
The user-facing display name for this application (this can be changed later). 
My New app 
Supported account types 
Who can use this application or access this API? 
@ Accounts in this organizational directory only (Default Directory only - Single tenant) 
O Accounts in any organizational directory (Any Azure AD directory - Multitenant) 
O Accounts in any organizational directory (Any Azure AD directory - Multitenant) and personal Microsoft accounts (e.g. Skype, Xbox) 
Help me choose... 
Redirect URI (optional) 
We'll return the authentication response to this URI after successfully authenticating the user. Providing this now is optional and it can be 
changed later, but a value is required for most authentication scenarios. 
web 
v http /mynewapp.azurewebsites.net 
gy proceeding, you agree to the Microsoft Platform Policies 
Register

I've picked single tenant as I want to invite users using B2B. Now click Register

You need to copy the ID's needed for your web app:

Delete Endpoints 
O 
Got a second? We would love your feedback on Microsoft identity platform (previously Azure AD for developer). * 
Display name 
Application (client) ID 
Directory (tenant) ID 
Object ID 
My New app 
Supported account types 
: My organization only 
Redirect URIS 
: I web, O public client 
Application ID URI 
: Add an Application ID URI 
Managed application in My New app

Copy the Client ID and Tenant ID. Repeat this process for the next app. I've created two apps as I wanted to test limiting access to a single app and deny access to the second if the users has not been invited to it or added manually.

Now add these to the web.config in the sample app. There will be two settings for ClientId and Tenant. Make sure that the redirect url matches the url of the application you registered and redeploy. Repeat this for the second application.

If you navigate to the web apps and try and login, you may get an error as we haven't setup any users, although any users currently in your Azure AD should be able to login.

To give users access to your app. Go back to Azure Active Directory and this time select Enterprise Applications and click on the app you just created.