ASP.Net Identity in Azure Cloud - asp.net

I have a problem with ASP.Net Identity used in application scaled to two instances. It seems that we have problem with checking password (checking hashes?) or verifying generated tokens (for example: password reset). When application works on one instance, then everything seems to be fine. It's weird because I read that using ASP.Net Identity in Azure cloud should be safe - it should use the same machine key on both instances.
Our user manager use token provider created below:
public DataProtectorTokenProvider<ExternalUser> Create(string purpose = "GeneralPurpose")
{
var provider = new DpapiDataProtectionProvider(_appName);
var result = new DataProtectorTokenProvider<ExternalUser>(provider.Create(purpose));
return result;
}
What is more, our user manager is singleton, but I think it shouldn't be a difference.
Any idea why it doesn't work on two instances in Azure? I will appreciate any help or advice.

Related

On-prem ASP.NET Framework web app with Azure Key Vault

We're in the process of trying to secure our application secrets in our internal ASP.NET Framework web applications. The initial plan offered to me was to use Azure Key Vault. I began development work using my Visual Studio Enterprise subscription, and that seems to work fine, locally.
We've created a second Key Vault in our company's production environment, and again, I can use it locally, because my own AAD account has access to the vault. However, in this project (4.7.2 Web Forms web application), I don't see any means of specifying the Access Policy principal that we've created for the application.
My google-fu is failing me: is there any documentation that explains how to do this? Is this scenario -- an on-prem, ASP.NET Framework app outside of the Azure environment, accessing Key Vault for confiugation values -- even possible?
Thanks.
UPDATE: I was unable to find a solution that would allow me to use the Access Policy principal from within the "Add Connected Service" dialog. I'm somewhat surprised it's not in there, or is hidden enough to elude me. So I ended up writing my own Key Vault Secret-Reader function, similar to the marked answer. Hope this helps someone...
In this scenario, your option is to use the service principal to access the keyvault, please follow the steps below, my sample get the secret from the keyvault.
1.Register an application with Azure AD and create a service principal.
2.Get values for signing in and create a new application secret.
3.Navigate to the keyvault in the portal -> Access policies -> add the correct secret permission for the service principal.
4.Then use the code below, replace the <client-id>, <tenant-id>, <client-secret> with the values got before.
using System;
using Microsoft.Azure.KeyVault;
using Microsoft.Azure.Services.AppAuthentication;
namespace test1
{
class Program
{
static void Main(string[] args)
{
var azureServiceTokenProvider = new AzureServiceTokenProvider("RunAs=App;AppId=<client-id>;TenantId=<tenant-id>;AppKey=<client-secret>");
var kv = new KeyVaultClient(new KeyVaultClient.AuthenticationCallback(azureServiceTokenProvider.KeyVaultTokenCallback));
var secret = kv.GetSecretAsync("https://keyvaultname.vault.azure.net/", "mySecret123").GetAwaiter().GetResult();
Console.WriteLine(secret);
}
}
}

Not able to connect to Azure Key Vault when using Service Identity

I am trying to retrieve secrets from Azure Key Vault using Service Identity in an ASPNet 4.6.2 web application. I am using the code as outlined in this article. Locally, things are working fine, though this is because it is using my identity. When I deploy the application to Azure I get an exception when keyVaultClient.GetSecretAsync(keyUrl) is called.
As best as I can tell everything is configured correctly. I created a User assigned identity so it could be reused and made sure that identity had get access to secrets and keys in the KeyVault policy.
The exception is an AzureServiceTokenProviderException. It is verbose and outlines how it tried four methods to authenticate. The information I'm concerned about is when it tries to use Managed Service Identity:
Tried to get token using Managed Service Identity. Access token could
not be acquired. MSI ResponseCode: BadRequest, Response:
I checked application insights and saw that it tried to make the following connection with a 400 result error:
http://127.0.0.1:41340/MSI/token/?resource=https://vault.azure.net&api-version=2017-09-01
There are two things interesting about this:
Why is it trying to connect to a localhost address? This seems wrong.
Could this be getting a 400 back because the resource parameter isn't escaped?
In the MsiAccessTokenProvider source, it only uses that form of an address when the environment variables MSI_ENDPOINT and MSI_SECRET are set. They are not set in application settings, but I can see them in the debug console when I output environment variables.
At this point I don't know what to do. The examples online all make it seem like magic, but if I'm right about the source of the problem then there's some obscure automated setting that needs fixing.
For completeness here is all of my relevant code:
public class ServiceIdentityKeyVaultUtil : IDisposable
{
private readonly AzureServiceTokenProvider azureServiceTokenProvider;
private readonly Uri baseSecretsUri;
private readonly KeyVaultClient keyVaultClient;
public ServiceIdentityKeyVaultUtil(string baseKeyVaultUrl)
{
baseSecretsUri = new Uri(new Uri(baseKeyVaultUrl, UriKind.Absolute), "secrets/");
azureServiceTokenProvider = new AzureServiceTokenProvider();
keyVaultClient = new KeyVaultClient(
new KeyVaultClient.AuthenticationCallback(azureServiceTokenProvider.KeyVaultTokenCallback));
}
public async Task<string> GetSecretAsync(string key, CancellationToken cancellationToken = new CancellationToken())
{
var keyUrl = new Uri(baseSecretsUri, key).ToString();
try
{
var secret = await keyVaultClient.GetSecretAsync(keyUrl, cancellationToken);
return secret.Value;
}
catch (Exception ex)
{
/** rethrows error with extra details */
}
}
/** IDisposable support */
}
UPDATE #2 (I erased update #1)
I created a completely new app or a new service instance and was able to recreate the error. However, in all instances I was using a User Assigned Identity. If I remove that and use a System Assigned Identity then it works just fine.
I don't know why these would be any different. Anybody have an insight as I would prefer the user assigned one.
One of the key differences of a user assigned identity is that you can assign it to multiple services. It exists as a separate asset in azure whereas a system identity is bound to the life cycle of the service to which it is paired.
From the docs:
A system-assigned managed identity is enabled directly on an Azure service instance. When the identity is enabled, Azure creates an identity for the instance in the Azure AD tenant that's trusted by the subscription of the instance. After the identity is created, the credentials are provisioned onto the instance. The lifecycle of a system-assigned identity is directly tied to the Azure service instance that it's enabled on. If the instance is deleted, Azure automatically cleans up the credentials and the identity in Azure AD.
A user-assigned managed identity is created as a standalone Azure resource. Through a create process, Azure creates an identity in the Azure AD tenant that's trusted by the subscription in use. After the identity is created, the identity can be assigned to one or more Azure service instances. The lifecycle of a user-assigned identity is managed separately from the lifecycle of the Azure service instances to which it's assigned.
User assigned identities are still in preview for App Services. See the documentation here. It may still be in private preview (i.e. Microsoft has to explicitly enable it on your subscription), it may not be available in the region you have selected, or it could be a defect.
To use a user-assigned identity, the HTTP call to get a token must include the identity's id.
Otherwise it will attempt to use a system-assigned identity.
Why is it trying to connect to a localhost address? This seems wrong.
Because the MSI endpoint is local to App Service, only accessible from within the instance.
Could this be getting a 400 back because the resource parameter isn't escaped?
Yes, but I don't think that was the reason here.
In the MsiAccessTokenProvider source, it only uses that form of an address when the environment variables MSI_ENDPOINT and MSI_SECRET are set. They are not set in application settings, but I can see them in the debug console when I output environment variables.
These are added by App Service invisibly, not added to app settings.
As for how to use the user-assigned identity,
I couldn't see a way to do that with the AppAuthentication library.
You could make the HTTP call manually in Azure: https://learn.microsoft.com/en-us/azure/active-directory/managed-identities-azure-resources/how-to-use-vm-token#get-a-token-using-http.
Then you gotta take care of caching yourself though!
Managed identity endpoints can't handle a lot of queries at one time :)

Create Database If Not Exist Without Restarting Application

I am creating dynamic connection strings in my project. They're created on the fly with the information provided specifically for every user. When the application first fires off, if a database doesn't exist (first time user logs on), a new database is created without problems with this initializer:
public DataContext() : base()
{
// ProxyCreation and LazyLoading doesn't affect the situation so
// comments may be removed
//this.Configuration.LazyLoadingEnabled = false;
//this.Configuration.ProxyCreationEnabled = false;
string conStr = GetDb();
this.Database.Connection.ConnectionString = conStr;
}
The problem is, with this method, I have to restart the application pool on the server and the new user should be the first accessor to the application.
I need the same thing without a requirement of restarting the app. Is that possible?
(This is a SPA using AngularJS on MVC views and WebApi as data provider - May be relevant somehow, so thought I should mention)
I already tried this, but this creates an error for EF and the application doesn't start at all...
You could try a little bit different approach to connect directly (and create) the right database.
public class DataContext : DbContext
{
public DataContext(DbConnection connection) : base(connection, true) { }
}
Here you create the DbContext already with the right connection.
Take also care because you need to specify to migrations that the right connection should be used (not the Web.Config connection but the connection that raised the database creation).
See the second overload here https://msdn.microsoft.com/en-US/library/hh829099(v=vs.113).aspx#M:System.Data.Entity.MigrateDatabaseToLatestVersion.

Extending current User class to handle Identity

We are using forms authentication on our ASP.NET website but are wanting to upgrade to the new Identity Provider. Currently we are using the database first approach and are ultimately wanting to just extend our current User table (not aspnet_users) to use the new identity format. We are using StructureMap to inject our context into our business logic classes. For instance our User service currently has this as its constructor:
private readonly SiteModelContainer _context;
public UserService(SiteModelContainer context)
{
this._context = context;
}
And in our IoC registry we have this:
var ecsbuilder = new EntityConnectionStringBuilder();
ecsbuilder.Provider = "System.Data.SqlClient";
ecsbuilder.ProviderConnectionString = #"data source=***;initial catalog=***;persist security info=True;User ID=***;Password=***;multipleactiveresultsets=True;App=EntityFramework";
ecsbuilder.Metadata = #"res://*/Data.***.csdl|res://*/Data.***.ssdl|res://*/Data.***.msl";
string connectionString = ecsbuilder.ToString();
For<SiteModelContainer>().Use<SiteModelContainer>().Ctor<string>("connectionString").Is(connectionString);
For<IUserService>().Use<UserService>();
...all the rest of our services
We are also using database first with EDMX and entity framework. Previously we just used ASP.NET authentication as it came out the box and had a separate user table to store profile information, but would like to have everything working off one users class instead.
1)Is it possible to extend our userservice to handle everything related to using Identity? So that Identity uses the same context that we inject into our classes? If so, I am unable to find any articles about it?
2) Are we able to extend our User object if it is created in the EDMX file?
Thanks
I have migrated 2 fairly large projects from MembershipProvider into Asp.Net Identity and both of the times I ended up rewriting most parts of the user-management and everything that touched user. A fairly chunky rewrites.
What you ask for is possible, but hard and very time consuming. You may start from this question - the OP have got his db-first project running with identity. And we had a discussion in comments with some links that might help you.

Multi-Tenant in windows azure asp.net MVC2

Anyone knows how can i start to develop a multitenant site in MVC2, in a way it run on Windows Azure?
I search a lot about this question, and i allways find theoric explanations, everybody says it can be easily done, but i dont find any sample...
Can someone explain me where to start?
Thanks,
João
It depends on how you plan on implementing multitenancy (eg. using authorization with common urls, subdomains, custom domains, or any combination). But you should be able to do just about any approach with Azure and MVC2. If you plan on using a custom domain for each tenant, versus a subdomain, you will need to be happy with using CNAME entries (not A records) to point each custom domain to Azure but that usually is not a problem.
MVC offers many extension points where you can implement multitenancy in its various flavors. The main goal is to uniquely identify the user by either a login or the url.
We have an MVC2 application running in Azure that parses the request url to differentiate the tenant. There are many ways to do this. We took the approach of extending the Controller class to provide our app with the unique tenant information so we could use it as needed to make appropriate repository calls to display the proper views etc.
Here is a sample of what a MultiTenant Controller might look like:
public class MultiTenantController : Controller {
public string TenantCode { get; set; }
protected override void OnActionExecuting(ActionExecutingContext filterContext) {
TenantCode = GetTenantCode(filterContext.HttpContext.Request);
}
private string GetTenantCode(System.Web.HttpRequestBase request) {
string host = new RequestParser(request.Url.AbsoluteUri).Host;
return _tenantService.GetTenantCodeByHostAddress(host);
}
}
NOTES:
The RequestParser function
above is just any implementation
that knows how to parse urls in a
safe manner.
_tenantService
can access some kind of persistent
store (Azure Tables in our case) to
get the TenantCode from the host
address in the url.
All of your controllers would inherit from the above class. Then, to differentiate between tenants you just refer to the TenantCode within your controller like so:
public class HomeController : MultiTenantController {
...
public ViewResult Index() {
var vm = _homeService.GetHomePageViewModelForTenant(TenantCode);
return View(vm);
}
}
Using the above implementation you could serve different sites or data to urls like the following:
http://subtenant1.yourdomain.com
http://subtenant2.yourdomain.com
http://www.customtenantdomain.com
Your backend store (eg. Table Storage) just needs to cross reference host names with the tenant like the table below. In the code above GetTenantCode would access the data.
HostName TenantCode
---------------------- --------------
subtenant1 Tenant1ID
subtenant2 Tenant2ID
www.customtenantdomain Tenant3ID
For www.customtenantdomain.com to work, the tenant needs a CNAME entry for www in their DNS records for customtenantdomain.com that points to your Azure Web Role's address.
Its hugely complex and not something to be taken on lightly. However take a look at the source code for Microsoft's Orchard project. This has full multi-tenancy capabilities if thats what you need: http://orchard.codeplex.com/
And they have a build that works in Azure too.
In this guide we cover aspects of this and it includes a full sample using MVC 2.
link text
First , all answers are very very helpful.It's changing your decision what you want setting up your multitenancy.I mean the most important thing is Identifying all tenant in your app so there is a lot of way for solution.For example you can hold your tenant via subdomains or URL surfing.And also maybe you can store your data multitenat database.
There are very very helpul posts are written by Steve Morgan.
I only help you for set startup multi- tenancy.Here are the blogs :
Identifying the Tenant in Multi-Tenant Azure Applications - Part 1
Identifying the Tenant in Multi-Tenant Azure Applications - Part 2
Identifying the Tenant in Multi-Tenant Azure Applications - Part 3
And here are the Multi-Tenant Data Strategies for Windows Azure :
Multi-Tenant Data Strategies for Windows Azure – Part 1
Multi-Tenant Data Strategies for Windows Azure – Part 2

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