Android-IPhone Deployment Security considerations with .NET Maui - .net-maui

I am used to .Net Core deployments on the server side calling webservices, so API calls are called server side.
I am now developing a portal using hybrid, .NET MAUI/Blazor. So razor views, services and C# inline.
The injected service is called from the inline, so the keys are not visible to the user but they are in the package making part of a call to a third party API. IP restrictions are not relevant here, it's a public portal so individual certs are no appropriate, so Azure AD examples online have keys in a settings file.
Is this safe? Is the app compiled, signed, encrypted etc by default. I have seen a Android specific secure storage API but believe this is more for keys or items they may enter locally on the phone. All API's are HTTPS so encrypted once in the packet, obviously want to avoid a bad actor getting the keys.

Related

How we can store API keys encrypted inside .net core console application

I am working on a .NET core console application which integrates with 3rd party APIs. and to do the integration I need to pass the API keys inside the API requests. so my question is where/how I can store the API keys inside my console application? in regular .NET console application I use to store the API keys inside the app.config and encrypt the keys using Aspnet_regiis.. but not sure how i can do so inside .NET core console application?
You can consider...
Get separate keys issued for different environments (so that a compromised key can be expired/cancelled without affecting other environment/s).
Store keys encrypted - for example - in the operating system provided key store [https://learn.microsoft.com/en-us/dotnet/standard/security/cryptography-model]. (This just means that they are not "left lying around" for casual passers by.)
Remove the code for retrieval of keys from the console app, perhaps to a simple service or library to which code the regular developers do not have access. (A level of separation.)
To embed information within the application, consider resource files [https://learn.microsoft.com/en-us/dotnet/framework/resources/creating-resource-files-for-desktop-apps]
Bottom line: This question illustrates the raison d'être for public key (asymmetric) cryptography [https://en.wikipedia.org/wiki/Public-key_cryptography] but any app that handles a piece of information "decrypted in flow" makes that information vulnerable to everyone who has permission to work on (debug) the live app or poke around with diagnostic tools on the system. (If a person needs a key to open a door then you must give them a key with which to open it and can't then prevent dishonest misuse of that privilege.)
A little bit of paranoia is healthy but too much can be an obstacle to getting things done.
Security in Development
For local development, you can use the Secrets Manager Tool (used only in development, never in production). This tool allows you to store your sensitive data locally on your machine, outside the project tree.
This tool is not super secure, and the keys are not encrypted, but it provides an easy way to avoid storing secrets in your project config files and having to remember to add them to the source control ignore list.
Security in Production
A common way is to store secrets in an external vault.
If you are hosting your application on Azure, Azure also provides a more secure option: Azure Key Vault.
Key Vault is a cloud-hosted service for managing secrets, which will be accessible by the applications you authorize through an encrypted channel.
It is advisable not to store encrypted keys inside a .NET console application. It is more ideal to keep secrets separate, store them using the Secret management tool in dev mode, and look into services like Azure KeyVault for production as mentioned earlier.
See the link about app secrets and configuration and why we need a tool to manage it on https://dev.to/dotnet/how-to-store-app-secrets-for-your-asp-net-core-project-2j5b for detailed instructions on how to do this.

What are the differences between the online storage and authentication options offered by Microsoft Azure?

I would like to develop a simple ToDo app using Xamarin. It should allow the user to sign in with an account and access their notes on multiple platforms.
Microsoft offer a number of sample applications using different APIs (https://developer.xamarin.com/samples/android/Web%20Services), but to a beginner, it seems unclear what the advantages and disadvantages are of the different methods. I'd be grateful if you could outline these for me for the differing technologies (e.g. CosmosDB, REST, ASMX, DocumentDB, Azure Mobile App, and OAuth).
CosmosDB:
Azure Cosmos DB is Microsoft's globally distributed, multi-model database service. With a click of a button, Cosmos DB enables you to elastically and independently scale throughput and storage across any number of Azure regions worldwide. For details You Could Check here
REST:
Representational State Transfer in short (REST), REST requires that a client make a request to the server in order to retrieve or modify data on the server. A request generally consists of:
an HTTP verb, which defines what kind of operation to perform
a header, which allows the client to pass along information about the
request
a path to a resource
an optional message body containing data
There are many good article you could found online. you can check here
ASMX:
.asmx is Active server methods. Webservices have this extension in dotnet. ASMX provides the ability to build web services that send messages using the Simple Object Access Protocol (SOAP). SOAP is a platform-independent and language-independent protocol for building and accessing web services. You can find more details here
DocumentDB:
CosmosDb is the evolved version of documentDb. It is also important to point out that DocumentDB’s SQL dialect has always been just one of the many APIs that the underlying Cosmos DB was capable of supporting.
Azure Mobile App:
Azure App Service is a fully managed platform as a service (PaaS) offering for professional developers. The service brings a rich set of capabilities to web, mobile, and integration scenarios. You can start good tutorial here
OAuth:
OAuth is an open-standard authorization protocol or framework that describes how unrelated servers and services can safely allow authenticated access to their assets without actually sharing the initial, related, single logon credential. In authentication parlance, this is known as secure, third-party, user-agent, delegated authorization. You could check here

How can I use AAD for an Azure version of "Windows Authentication" from a Web App to a Web API App?

I have two applications:
MVC Site (User-facing Web App secured via OAuth -> Google)
Web API Site ("Private" Web Services)
These are hosted in an App Service Plan in Azure. These web services will only be consumed by my own applications - I don't need to worry about outside consumption. In fact, I specifically don't want outside consumption. My Web App is using OAuth to Google - that shouldn't matter here.
So to get to the heart of my question: My web services currently have no authentication/authorization model in the code but I don't want it just publicly available to anybody. On prem, we just lock this down via IIS using Windows Auth and set the service account for the consuming web app to run as a user that Windows Auth allows access to. I'd like to do the equivalent in Azure.
I understand Azure isn't exactly the same but I have to believe this is possible. I have even gotten my web services locked down the way I want using the settings in the Authentication/Authorization tab (I can try to navigate to it but I only get my Swagger UI once I login with a valid organizational account). So half of my battle is solved but I cannot figure out how to do the other half - the equivalent of setting the service account for my consuming MVC application to run as.
Can I do this via the portal without having to code specifically to this scenario? I'd really like a PaaS-level or IaaS-level solution for the security portion of consuming the above locked-down services. I'm also open to other avenues if I'm going down the wrong path in having a PaaS or IaaS security solution to this problem. I'm not against making code changes - we did have a one-liner in our RestSharp code to engage Windows Authentication, but the bulk of the work/configuration was outside of code and that's what I'm going for here.
If going the IaaS path you can host the application inside of an VM in the exact same way as you did before when running it directly on-top of IIS. The benefit is that you can get running the same way as before but you will still need to manage the VM; i.e install updates and take care of its security.
However, if you want to have a PaaS solution, then you need to modify the code of your front-end application to pass on the authentication token to the back-end API, assuming the back-end accepts the same authentication as the front-end. See https://azure.microsoft.com/en-us/documentation/articles/app-service-api-dotnet-get-started/ as an example on how to pass on authentication information from one app to another.
Alternatively you can use the app identity to make calls to your back-end API. This way the calls are not related to any user but are instead done in the context of the app. See https://github.com/Azure-Samples/active-directory-dotnet-daemon for more details on how to set it up, both configuration and needed code.
If you want to allow your users to sign-in using their Google accounts then you could handle authorization to your API using the app identity (second alternative above), assuming the API is independent of the requesting users identity.
Enabling authentication for a Azure Web App directly through the menus in the Azure Portal adds Azure AD authentication in-front of your application and require your to pass an access token generated by Azure AD to your API for it to work.

What is the difference between an API App and a Web App?

I've been reading a few tutorials now on deploying Web Apps and API Apps to Azure. However, I am still a little unsure as to why you would use one over another.
I can create a new .NET solution with API controllers and deploy this as a Web App, so why would I specifically require an API App? Are these optimized specifically for ASP.NET Web API, where as Web Apps are for delivering HTML?
Updating the answer to current state of Azure,
App Services now replaces all Mobile, Api and Web Apps flavors as a single app framework with all the functionality rolled over to make things more accessible across application types. Currently all of Web, Mobile and Api Apps are collectively called App Services. We still offer customer to be able to create a Mobile App and a Web App in the gallery but that is basically resolve into an App Service App.
https://azure.microsoft.com/en-us/documentation/articles/app-service-api-apps-why-best-platform/
Features for Mobile work for Web App as well such as Easy Tables and Easy API. And features for API apps like API Cors and API definitions now work on web apps as well. A customer can host a single web app to act as any mobile service or an api with all the features offered through the app services.
We also have a new service in preview particularly targeting API Apps by offering a management experience for your APIs, Basically you can control the generate try API pages, gather execution analytics, throttle and much more. Check out the feature blog to learn more about the Azure API Management Features. And yes you can host the APIs as a App Service App and hook things up with API Management.
https://azure.microsoft.com/en-us/documentation/articles/api-management-get-started/
There was a point in time when there were differences between the different app service types, but that is no longer true. The documentation now states:
The only difference between the three app types (API, web, mobile) is the name and icon used for them in the Azure portal.
So it no longer matters which app service type you choose to deploy to (unless you care what the icon looks like).
UPDATE
Function apps are now the exception. Creating a function app changes the user interface in the portal. The underlying web app, however, is no different. Setting an app setting named FUNCTIONS_EXTENSION_VERSION = ~1 turns any web app into a function app (minus the user interface in the portal).
There are many minor difference between Web API and API Apps, but the very notable and key differences are
Native Swagger implementation - When you create API App in Visual studio, swagger reference comes by default. Swagger provide very developer friendly features for API consumers to Interact with your API thru Swagger UI. Also Swagger based API's provides client SDK generation (both .Net based client and Javascript based client) which makes easy to call API's just like regular method call.
Note: Swagger implementation on regular Web API is possible manually.
Ability to publish your API Apps into Azure Market Place. Azure Market Place is the public repository for all API Apps that can be consumed freely or by charge.
this 15 minute video from Channel 9 gives an excellent overview about Api Apps.
To supplement Greg's answer, Here's an even more recent article describing the differences.
To sum up:
"The key features of API Apps – authentication, CORS and API metadata – have moved directly into App Service. With this change, the features are available across Web, Mobile and API Apps. In fact, all three share the same Microsoft.Web/sites resource type in Resource Manager."
And here's another important note:
"If your API is already deployed as a Web App or Mobile App, you do not have to redeploy your app to take advantage of the new features."
This can depend on what you are trying to do, but you would use a Web API when you are creating a service. ASP.Net Web API is a framework for building HTTP services that can be consumed by a broad range of clients. This allows you to build it not only for a web app, but have it open to connect to Android apps, IOS apps, web apps, Windows 8 apps, WPF apps etc..
So if you need a Web Service but you don't need SOAP then you can use Web API.
Here my comments:
API app:
Used for specific functionallity. Triggering that functionality from an URL.
Can be used to use with GET, POST, PUT, DELETE.
Can receive parameters at BODY (Json).
Response with valid status code (fail, sucess.)
Web APP: An application deployed with multiple functionallity, for example
a catalog for create, update and delete customers or to create a complete ERP.
Function APP: Is very similar to API app,
Used for specific functionallity. Triggering that functionality from an URL.
Can be used to use with GET, POST, PUT, DELETE.
Can receive parameters at BODY (Json).
Response with valid status code (fail, sucess.)
Actually you can deploy your aspnet webapi on Azure WebApp and a self host on Worker Roles.
On WebApp (former Azure websites), it will be deployed on IIS, so you can take advantage of IIS features.

Using Azure MobileServices library with my own LAN WebApi

I am currently doing some research for the development of a mobile application for our company that should support offline data sync (on an iPad). We have explored many possibilities including PhoneGap/Cordova, Xamarin and simply native iOS development. Xamarin, for many different reasons, seems to be our best choice, so my question will assume we will develop in Xamarin.
I was looking into a library for managing offline data synchronization and the most obvious solution is Microsoft Azure MobileServices. However, my company is Canadian, and apparently it's hard to trust (legally) our data to clouds based in the US. Since we already deployed internally our WebApi on our intranet, I figured there was probably a way to point the MobileServices library to our own WebApi. I have read about the Azure Hybrid Connection possibility, but our data still conveying through Microsoft servers might not be a possibility. So, my question is this:
Is there a way to configure the Microsoft.WindowsAzure.MobileServices Client library to point directly to our intranet, RESTful WebApi backend, without going through any Microsoft Azure servers ?
I understand that, in order to be able to use the Client librairies seamlessly, we probably would have to adapt our WebApi to implement the necessary .net Backend interfaces. I'm mostly wondering if it's even possible as the MSDN documentation on the libraries all seem to point to direct connections to their servers (no possibilities to configure your own connection strings) and all instructions redirect you to their Azure Mobile Services website.
Thank you.
If you look at the API for your mobile client, you'll notice that the Azure Mobile Services Client SDK only cares about two things:
new AzureMobileClient( url, appkey)
...where it's hosted shouldn't be a concern. Everything else is just configuration.
If you want to host the Azure Mobile Services Backend on your own servers, technically you could do this, but there are likely a few caveats. Microsoft has announced that they will be launching a Canadian Azure data center, but we won't see it until 2016.
In the meantime, here's how you can host the services locally. Note that I have not tried to emulate all of the features of Azure Mobile Services (aka Zumo) so your mileage (or kilometerage) will vary.
Hosting Locally:
From a technical feasibility, you absolutely can run the services locally. I know this because you can create the Azure Mobile Services Backend project from within Visual Studio and run it locally for development purposes. This is what our development team does for testing their mobile applications.
Note that you can create the Azure Mobile Service backend directly from within Visual Studio: New Project -> Cloud -> Azure Mobile Service. You can also download the exact same template (pre-configured with your URL and ApplicationKey) directly from the Azure dashboard: Create -> Mobile Service.
Obviously, if you're hosting it on your server it will be up to you to configure and use a proper SSL certificate for your site.
ZUMO Permissions:
By default, the security roles on the server are turned off. So if you're locking down any of your methods using the [AuthorizeLevel] attribute these settings will be ignored at runtime. If you need to enable this feature you can do so by modifying the WebApiConfig.Register() method and marking the site as self-hosted: config.SetSelfHosted(true).
Configuration:
From a configuration perspective, the Azure Mobile Service dashboard provides several tabs for configuring Identity, Push Notifications, Connection Strings and App Settings. Sadly, you won't have a dashboard, but all of these settings have a corresponding value in the local web.config. Any value you provide here is automatically overwritten in Azure, but they're used when running locally.
The minimum settings you'll need to configure are listed here. The ApplicationKey you can distribute with your ZuMo client, but the MasterKey is for the Admin authorization level so you'll want to keep that secret. The MobileServiceName is used by the EntityFramework for your database schema and what appears in the URL of your site.
<add key="MS_MobileServiceName" value="myzumosite" />
<add key="MS_MasterKey" value="masterkey" />
<add key="MS_ApplicationKey" value="appkey" />
Values that start with a MS_ prefix map to corresponding values in the Azure Portal. MS_GoogleClientID and MS_GoogleClientSecret map to the Google Identity values in the dashboard, for example.
Any other value in the AppSettings node is immediately accessible via the ApiServices.Settings property and corresponds to the Settings node in the Azure dashboard.
Database connection strings continue to exist in the connectionStrings node. The same is true for azure notification hub.
Database:
Obviously, the database you configure will be up to you as well. Permissions and User accounts are also obvious. There may be some minor differences between the SQL Azure syntax for Entity Framework database migration scripts that you'll need to worry about. (I've discovered the database migration scripts don't work from the Package Manager, but they do work when the database scripts are run when your website starts)
Caveats:
You will not have a nice dashboard for monitoring performance of your site, reviewing logs or changing runtime settings
You will not be able to scale out your site immediately; Scaling and deployment will be your problem
Deployment configuration is your responsibility (Project -> Publish won't be available unless you configure it)
Not sure if you'll be able to use Azure Active Directory as an authentication scheme, though from the sounds of it that won't be a concern. You can write your own authentication providers: Microsoft's Zumo library only supports a handful, but the underlying Owin.Security package that Microsoft uses supports several dozen systems!
Your site will need to be publically visible to your mobile clients
Push Notifications should work, but you will be using Azure's notification hub for this.
I have no idea where ApiServices.Log will go
The easiest path to take would be to:
Create the Mobile Service in Azure to get the notification hub and settings preconfigured
Download the starter site from the dashboard
Configure the web.config as mentioned here.
It's not possible to simply configure WAMS Client library to work with your own WebApi Backend.
But WAMS library is available at github, so I'm sure you can reuse a lot of code from the WAMS project, especially if you want to use a PCL project.
To route your data securly through Azure, you could think about setting up express route. Additionally, for last weeks update, it's possible to apply a custom domain to the WAMS Backend, including your own certificate to secure your connection.

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