How do I access the AZ Service Bus without a SAS Key - azure

I need help in creating access to AZ a service bus without using thr Shared Access Key in an Azure Function.
When I use the Endpoint, SharedAccessKeyName, SharedAccessKey, QueueName and RuleName it works great!
I can create the connection string like this:
string connectionString = string.Format("Endpoint={0};SharedAccessKeyName={1};SharedAccessKey={2}", Endpoint, SharedAccessKeyName, SharedAccessKey);
Manager = new Azure.Messaging.ServiceBus.Administration.ServiceBusAdministrationClient(connectionString);
I was told that I can use the AZ Identity to accomplish this same thing without the SAS Key.
I have not been able to figure out how to do this. In fact, I do not even know where to begin.

You can make your app to run under a managed Identity, and then configure your Azure Service Bus resource to allow access for that identity.
See the documentation and the sample code here.

Related

Azure Key Vault with App Service connection error

I'm trying to set up a new app slot for my azure website.
Here is my error:
I've looked at a few articles online and then made sure the app slot was using System assigned identities.
But I still get the above error?
What am I missing?
Here is what it looks like on the Configuration section
Make sure you have done the steps below, then it should work.
1.After enabling the system-assigned identity(MSI) of your slot, navigate to your keyvault in the portal -> Access policies -> add the MSI of your slot to the access policy with the correct secret permission, just search for your web app name, the MSI of the slot has the format as webappname/slots/slotname, details here.
2.If you use the SecretUri, the format of the connection string in your slot should be like below, double-check it.
#Microsoft.KeyVault(SecretUri=https://joykeyvault123.vault.azure.net/secrets/encryptionKey/492c7788a9da421c8b9752ef18b53f5d)
You could get the SecretUri in your secret in the portal.
It works fine on my side.

Can docker on Azure Linux App Service authenticate with the ACR without us specifying the password in the app settings?

We deploy a Linux App Service to Azure using terraform. The relevant configuration code is:
resource "azurerm_app_service" "webapp" {
app_settings = {
DOCKER_REGISTRY_SERVER_URL = "https://${local.ctx.AcrName}.azurecr.io"
DOCKER_REGISTRY_SERVER_USERNAME = data.azurerm_key_vault_secret.acr_admin_user.value
DOCKER_REGISTRY_SERVER_PASSWORD = data.azurerm_key_vault_secret.acr_admin_password.value
...
}
...
}
The problem is that terraform does not consider app_settings a secret and so it outputs in the clear the DOCKER_REGISTRY_SERVER_PASSWORD value in the Azure DevOps output (I obfuscated the actual values):
So, I am wondering - can docker running on an Azure Linux App Service host authenticate with the respective ACR without us having to pass the password in a way that makes it so obvious to every one who can inspect the pipeline output?
The following article seems relevant in general - https://docs.docker.com/engine/reference/commandline/login, but it is unclear how we can apply it in my context, if at all.
Also, according to https://feedback.azure.com/forums/169385-web-apps/suggestions/36145444-web-app-for-containers-acr-access-requires-admin#%7Btoggle_previous_statuses%7D Microsoft has started working on something relevant, but looks like this is still a work in progress (almost 5 months).
I'm afraid you must set the environment variables about DOCKER_REGISTRY_* to pull the images from the ACR, it's the only way to do that designed by Azure. But for the sensitive info about the password, it also provides a way to hide it. You can use the Key Vault to store the password in secret, and then get the password from the secret. Take a look at the document Use Key Vault references for App Service. So you can change the app_setting for the password like this:
DOCKER_REGISTRY_SERVER_PASSWORD = "#Microsoft.KeyVault(SecretUri=https://myvault.vault.azure.net/secrets/mysecret/ec96f02080254f109c51a1f14cdb1931)"
Or
DOCKER_REGISTRY_SERVER_PASSWORD = "#Microsoft.KeyVault(VaultName=myvault;SecretName=mysecret;SecretVersion=ec96f02080254f109c51a1f14cdb1931)"
Then it just shows the reference of the Key Vault, not the exact password.
Unfortunately Azure Web Apps do not support interacting with ACR using a managed identity, you must pass those Environment Variables to the App Service.
Terraform does not currently support applying a "sensitive" flag to arbitrary values. You can define outputs as sensitive, but it will not help with values you want to hide during the plan phase.
I would suggest checking out https://github.com/cloudposse/tfmask, using the TFMASK_RESOURCES_REGEX configuration to block the output you want to hide during your pipeline. If you're averse to adding dependencies, similar effect could be achieved by piping terraform apply through grep --invert-match "DOCKER_REGISTRY" instead.
#charles-xu has a good answer as well if you want to set up mappings between keyvault and your web app then push your tokens into kv secrets.
Now it's possible to use managed identity to pull images from ACR.
You may do the next:
go to your Container Registry page in the Azure portal
Open the tab Access Control (IAM)
The open Role assignments tab
Add role assignment AcrPull to your App Service or Function App
In the Deployment Center of your App Service choose Managed Identity for the Authentication setting.
Or you may use CLI by following the steps from the official documentation (link below):
https://learn.microsoft.com/en-us/azure/app-service/configure-custom-container?pivots=container-linux#use-managed-identity-to-pull-image-from-azure-container-registry
After you added role assignment DOCKER_REGISTRY_SERVER_URL, DOCKER_REGISTRY_SERVER_USERNAME and DOCKER_REGISTRY_SERVER_PASSWORD settings may be removed from App Service's App Settings.

Use Azure keyvault secrets offline when developing .NET core Azure functions

When I develop for Azure I usually start copying in some keyvault client code so only keyvault urls will be in my settings file, no secrets can ever end up my git repositories.
After starting to make Azure functions I realized that it was not possible to do this for the trigger connection string for e.g. service bus or blob storage.
The recommended approach seems to connect the app to keyvault directly in Azure when deployed, and just manage secrets locally in Secret Manager, like suggested in
this article
I am not developing alone, so while I am not adverse to using a tool like Secret Manager, I need to still have my offline secrets connected to the Azure keyvault! If others change anything.
Question: How do I manage secrets offline in a way that is synchronized with Azure keyvault?
it was not possible to do this for the trigger connection string for e.g. service bus or blob storage.
In short, it's possible.
Here are steps you could follow and refer to the detailed article.
1.Add a System Assigned Managed Identity to the Azure Function.
2.Go to the Access Control section of your Key Vault and click on Add a role assignment blade.
3.Go to your Key Vault and click on Access Policies and then click on Add service principal with secret GET permission.
4.When you use ServiceBusTrigger, you set ServiceBusConnectionString in Function ->Configuration ->Application settings.
public static void Run([ServiceBusTrigger(_topicName, _subscriptionName, Connection = "ServiceBusConnectionString")] string mySbMsg, ILogger log)
{ ....
}
5.Now you change the value of ServiceBusConnectionString to the Azure Key Vault reference with #Microsoft.KeyVault(SecretUri=Secret URI with version). Then you could run your function successfully with Key Vault.

Keyword not supported: #microsoft.keyvault

I was trying to get the connection string from the azure key vault for azure functions. These are the steps I did,
Created a managed identity(System assigned) in the azure functions
Create a secret in an azure key vault
Add access policies to give permission to the azure function app
Added an entry in the app settings for connection string where the value was #Microsoft.KeyVault(SecretUri=SECRETURLOFKEYVAULT)
But when I run the azure function I am getting below error,
"Keyword not supported: #microsoft.keyvault(secreturi....."
This is how I have enabled managed identity,
And my access policy looks like below,
Any help would be much appreciated
I ran into a similar problem by following the tutorial. My remedy was a restart of the function app. Saving of the app setting was not enough for the Function App to start using the Key Vault secret provider correctly.
According to the steps you provided, it have no problem to work well. Here is the tutorial about get key vault secrets in Azure Function you could refer to.
Note: Add access policies to the azure function app with the Get permission on secrets and that was enough.
Also, here is a similar issue that get same error like you which is due to IP Address restriction blocking it.
This issue occurred while testing on local. It was resolved after doing an az login.

How to map Azure Functions secrets from Key Vault automatically

I was wondering if it's possible to initialize the queue trigger or even the blob trigger off a connection string that is read from azure vault.
Right now, we have to set these data connection via environment settings via blade properties. However, I wanted to just use the service principal to retrieve the token for the azure key vault to get all these connection strings.
I'm trying to figure how to get this working in java.
Thanks,
Derek
This feature is tracked and in progress here:
Feature request: retrieve Azure Functions' secrets from Key Vault
Add binding to Key Vault
EDIT 28/11/2018: It is currently in preview
Simplifying security for serverless and web apps with Azure Functions and App Service
Former answer 07/10/2018
This solution won't work for Triggers using the consumption plan.
In the mean time I did some research about your problem and it is possible to read config from key vault if you use Azure Function v2.
I've created an Azure Functions v2 (.NET Standard) from Visual Studio.
It uses:
NETStandard.Library v2.0.3
Microsoft.NET.Sdk.Functions v1.0.22
Microsoft.Azure.WebJobs v3.0.0
Microsoft.Azure.WebJobs.Extensions.Storage v3.0.0
Because Azure Functions v2 uses ASP.NET core, I was able to reference this link to configure my functions app to use Azure Key Vault:
Azure Key Vault configuration provider in ASP.NET Core
I've added this nuget package:
Microsoft.Extensions.Configuration.AzureKeyVault
I've configured my app to use this nuget package:
using Microsoft.Azure.WebJobs;
using Microsoft.Azure.WebJobs.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using System.Linq;
[assembly: WebJobsStartup(typeof(FunctionApp1.WebJobsExtensionStartup), "A Web Jobs Extension Sample")]
namespace FunctionApp1
{
public class WebJobsExtensionStartup : IWebJobsStartup
{
public void Configure(IWebJobsBuilder builder)
{
// Get the existing configuration
var serviceProvider = builder.Services.BuildServiceProvider();
var existingConfig = serviceProvider.GetRequiredService<IConfiguration>();
// Create a new config based on the existing one and add kv
var configuration = new ConfigurationBuilder()
.AddConfiguration(existingConfig)
.AddAzureKeyVault($"https://{existingConfig["keyVaultName"]}.vault.azure.net/")
.Build();
// replace the existing configuration
builder.Services
.Replace(ServiceDescriptor.Singleton(typeof(IConfiguration), configuration));
}
}
}
My Azure functions uses MSI:
I've granted Read/List secrets permissions to the function app on my key vault:
I have a small queue triggered function:
public static class Function2
{
[FunctionName("Function2")]
public static void Run([QueueTrigger("%queueName%", Connection = "queueConnectionString")]string myQueueItem, ILogger log)
{
log.LogInformation($"C# Queue trigger function processed: {myQueueItem}");
}
}
The queueName is defined in the local.settings.json file (App settings blade once deployed):
{
"IsEncrypted": false,
"Values": {
"AzureWebJobsStorage": "UseDevelopmentStorage=true",
"FUNCTIONS_WORKER_RUNTIME": "dotnet",
"keyVaultName": "thomastestkv",
"queueName": "myqueue"
}
}
The queueConnectionString is configured in my keyvault:
Sourcing Application Settings from Key Vault
The Key Vault references feature makes it so that your app can work as if it were using App Settings as they have been, meaning no code changes are required. You can get all of the details from our Key Vault reference documentation, but I’ll outline the basics here.
This feature requires a system-assigned managed identity for your app. Later in this post I’ll be talking about user-assigned identities, but we’re keeping these previews separate for now.
You’ll then need to configure an access policy on your Key Vault which gives your application the GET permission for secrets. Learn how to configure an access policy.
Lastly, set the value of any application setting to a reference of the following format:
#Microsoft.KeyVault(SecretUri=secret_uri_with_version)
Where secret_uri_with_version is the full URI for a secret in Key Vault. For example, this would be something like: https://myvault.vault.azure.net/secrets/mysecret/ec96f02080254f109c51a1f14cdb1931
That’s it! No changes to your code required!
For this initial preview, you need to explicitly set a secret version, as we don’t yet have built-in rotation handling. This is something we look forward to making available as soon as we can.
User-assigned managed identities (public preview)
Our existing support for managed identities is called system-assigned. The idea is that the identity is created by the platform for a specific application and is tied to the lifecycle of the application. If you delete the application, the identity is removed from Azure Active Directory immediately.
Today we’re previewing user-assigned identities, which are created as their own Azure resource and then assigned to a given application. A user-assigned identity can also be assigned to multiple applications, and an application can have multiple user-assigned identities.
more details check this
Update
This is now GA
This was just released as preview a couple days ago.
This feature requires a system-assigned managed identity for your app. Later in this post I’ll be talking about user-assigned identities, but we’re keeping these previews separate for now.
You’ll then need to configure an access policy on your Key Vault which gives your application the GET permission for secrets. Learn how to configure an access policy.
Lastly, set the value of any application setting to a reference of the following format:
#Microsoft.KeyVault(SecretUri=secret_uri_with_version)
Where secret_uri_with_version is the full URI for a secret in Key Vault. For example, this would be something like: https://myvault.vault.azure.net/secrets/mysecret/ec96f02080254f109c51a1f14cdb1931
Using Keyvault integration within the function runtime
I just implemented it in Java following below two references.
https://learn.microsoft.com/en-us/azure/app-service/app-service-key-vault-references
https://medium.com/statuscode/getting-key-vault-secrets-in-azure-functions-37620fd20a0b
in java use System.getenv("SECRET_KEY") to read the values from your app settings.
Happy to help if you need further assistance.
I have already given my answer in above, this answer is for #Matt Sanders's comment,
i just want to explain how MSI working in the Azure Environment,
"I have 2 user assigned identities, 1 has permissions to KeyVault, the other does not. How can you specify the correct user assigned an identity to use for retrieving the secret? I'm guessing this is not possible and User Assigned Identities are not supported even though they are listed in your answer. – Matt Sanders"
when you want to use Azure Manage Identity Service, your application must register in the Azure AD, for an example, lets say multiple users accessing your web application and, within your web application, you 'r trying to access vVault's secrets, In that case, vault doesnt care about the users that consume your application, it cares about the application,
please reffer below image,
I as showing the picture, only Azure Function added as an Identity to the vault, other applications are not,
so whoever using Azure function can access vault's secrets, according to this example only A and B can access secrets,

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