Is it safer to have a authentication/authrorization microservice? - authentication

My application has a microservice architecture. Right now I have implemented JWT into my "backend" microservice. But I was wondering to add authentication and authroization into a different microservices. I dont know if this is safer or what the security risks are?
Does someone has an idea?

It is perfectly fine to have a different microservice for authntication and authorization.. This would be esp. very useful if in future you would have many applications and want to have SSO ( single sign on ) so all applications can call this microservice. This is how it is done everywhere.
If u are aware of suppose AWS; they have 100's of services and whenever we call api of these services those requests should be authenticated. Hence, they have a single service IAM for this.

Related

Microservices - IPC authentication/authorization

We're trying to figure out a best practice for IPC authentication and authorization. I'll explain.
We have a micro-services based architecture SaaS with a dedicated service for authentication. This service is responsible for doing the authentication and managing auth tokens (JWTs).
Everything works perfectly good with users that login and start to consume resources from the different services.
The question now is how to authentication and authorize requests which being initiated by other services (without the context of a specific user)?
Should we generate a dedicated user per service and treat it like
any other user in the system (with appropriate permissions)?
Should
we have a "hard coded"/dynamic token deployed among the services?
Any other ideas?
Our biggest concern is such tokens/passwords will be compromised at some point since requests from one service to another is treated with high level of permissions.
Cheers,
I'm not a microservices expert, just started to get my feet wet in the microservices world. From what I've read until now, this could be handled in many ways, one of which as you mentioned is hard coding api-keys so that services recognise one another. But I never liked this idea personally - also using a user per service like you mentioned. A solution I really liked is using Oauth2 for handling these scenarios - an interesting implementation I found is Gluu Server and I think client credentials grant type is what you're looking for - refer https://gluu.org/docs/integrate/oauth2grants/.
Have fun :)
Normally, API Gateway is integral part of any MS system.
All the services encapsulated and should be not accessible without API Gateway.
Such encapsulation allows direct communication between the services, without providing the requester payload, which should be required if the request comes straight from API Gateway.
In that case the request threated as something different, and follows different logic/middleware pipeline. No additional special users needed.

Microservices - how to solve security and user authentication?

There is a lot of discussion about microservice architecture. What I am missing - or maybe what I did not yet understand is, how to solve the issue of security and user authentication?
For example: I develop a microservice which provides a Rest Service interface to a workflow engine. The engine is based on JEE and runs on application servers like GlassFish or Wildfly.
One of the core concepts of the workflow engine is, that each call is user centric. This means depending of the role and access level of the current user, the workflow engine produces individual results (e.g. a user-centric tasklist or processing an open task which depends on the users role in the process).
In my eyes, thus a service is not accessible from everywhere. For example if someone plans to implement a modern Ajax based JavaScript application which should use the workflow microservice there are two problems:
1) to avoid the cross-scripting problem from JavaScript/Ajax the JavaScript Web application needs to be deployed under the same domain as the microservice runs
2) if the microservice forces a user authentication (which is the case in my scenario) the application need to provide a transparent authentication mechanism.
The situation becomes more complex if the client need to access more than one user-centric microservices forcing user authentication.
I always end up with an architecture where all services and the client application running on the same application server under the same domain.
How can these problems be solved? What is the best practice for such an architecture?
Short answer: check OAUTH, and manage caches of credentials in each microservice that needs to access other microservices. By "manage" I mean, be careful with security. Specially, mind who can access those credentials and let the network topology be your friend. Create a DMZ layer and other internal layers reflecting the dependency graph of your microservices.
Long answer, keep reading. Your question is a good one because there is no simple silver bullet to do what you need although your problem is quite recurrent.
As with everything related with microservices that I saw so far, nothing is really new. Whenever you need to have a distributed system doing things on behalf of a certain user, you need distributed credentials to enable such solution. This is true since mainframe times. There is no way to violate that.
Auto SSH is, in a sense, such a thing. Perhaps it may sound like a glorified way to describe something simple, but in the end, it enables processes in one machine to use services in another machine.
In the Grid world, the Globus Toolkit, for instance, bases its distributed security using the following:
X.509 certificates;
MyProxy - manages a repository of credentials and helps you define a chain of certificate authorities up to finding the root one, which should be trusted by default;
An extension of OpenSSH, which is the de facto standard SSH implementation for Linux distributions.
OAUTH is perhaps what you need. It is a way provide authorization with extra restrictions. For instance, imagine that a certain user has read and write permission on a certain service. When you issue an OAUTH authorization you do not necessarily give full user powers to the third party. You may only give read access.
CORS, mentioned in another answer, is useful when the end client (typically a web browser) needs single-sign-on across web sites. But it seems that your problem is closer to a cluster in which you have many microservices that are managed by you. Nevertheless, you can take advantage of solutions developed by the Grid field to ensure security in a cluster distributed across sites (for high availability reasons, for instance).
Complete security is something unattainable. So all this is of no use if credentials are valid forever or if you do not take enough care to keep them secret to whatever received them. For such purpose, I would recommend partitioning your network using layers. Each layer with a different degree of secrecy and exposure to the outside world.
If you do not want the burden to have the required infrastructure to allow for OAUTH, you can either use basic HTTP or create your own tokens.
When using basic HTTP authentication, the client needs to send credentials on each request, therefore eliminating the need to keep session state on the server side for the purpose of authorization.
If you want to create your own mechanism, then change your login requests such that a token is returned as the response to a successful login. Subsequent requests having the same token will act as the basic HTTP authentication with the advantage that this takes place at the application level (in contrast with the framework or app server level in basic HTTP authentication).
Your question is about two independent issues.
Making your service accessible from another origin is easily solved by implementing CORS. For non-browser clients, cross-origin is not an issue at all.
The second problem about service authentication is typically solved using token based authentication.
Any caller of one of your microservices would get an access token from the authorization server or STS for that specific service.
Your client authenticates with the authorization server or STS either through an established session (cookies) or by sending a valid token along with the request.

Authentication and Authorization for a simple Web Site

I'm struggling with these concepts and having trouble finding good resources on the web.
We are looking for ways to switch out custom implementations tightly integrated into our application for standards based authentication and authorization.
Our scenario is as follows:
A simple web site (may be an app in the nearby future)
A user must log in or otherwise gain access (i.e. there's no "guest" content or other things you can do as a guest)
The site uses its own web services (REST and/or SOAP) on the backend, but it might use 3rd party web services or exposes its own services as 3rd party services for other applications
Authentication may very well be done by an external provider: Users carry a smartcard and we'd like to have one simple identity provider which reads the smartcard information and sends it back to my simple web site (so I know who the user is and what his role is for instance)
Other sites might use other methods of authentication (simple username/password for instance), so we might need a configurable Service Provider??
I'm currently looking at OAuth (2) to implement for authorizing use of our REST Services (is it also useful for SOAP?) to our web site, perhaps with a simple "Client Credentials Grant" type.
But for authentication, I'm still none the wiser. There is OpenID, but is it easy enough to build your own OpenID Identity Provider? There is Shibboleth, but it seems to have a steep learning curve for doing custom stuff. And I've looked at just building something from scratch based on the SAML Authentication Request Protocol with an HTTP Post binding. Are there any other options?
Please keep in mind that we want to be flexible with our authentication. For a certain site, we might want to do the smartcard thing, but for another maybe simple username/password login with LDAP.
If it's helpful still, I personally thought about doing it myself, then discovered a bunch of third parties. I compared (5/18/2015):
Auth0
AuthRocket
UserApp
DailyCred
Conclusion for me was Auth0, because while all the features are very similar, it felt the most legitimate, as in it's not a start-up that might disappear in a few months. Now, the reason that was super important for me was because login is a foundational requirement, so I need to believe as a customer that the Authentication as a Service will be up for as long as I will be.
Here's the full comparison story:
https://medium.com/#bsemaj/authentication-as-a-service-comparison-5-quick-lessons-for-b2b-businesses-e7587275824c

Web API authentication/authorization using SSO instead of OAUTH - will it work?

Updated based on questions from #user18044 below
If a user is authenticated in two different web applications via 2 different SAML-based identity providers, and one of the applications needs to request data from a web API exposed by the other application, would it be possible to call the web API methods securely by virtue of the user's current authenticated status in both applications without separately securing the API methods via an API level authentication protocol such as OAUTH? Note that both applications are owned and operated by my company and share the same 2nd level domains and user base, even though the identity servers are different (one is legacy).
Some further information: Application A is a portal application that is going to host widgets using data supplied from Application B. Application A will only communicate with application B via a web API exposed by application B. Currently application B does not expose a web API (except internally to the application itself). This is new functionality that will need to be added to application B. Application A will use Okta as its SSO. Our lead architect's proposal is to continue to use a custom legacy IDP server that we developed internally based around using the dk.nita.saml20 DLL. They are both SAML based I believe, but I don't think they could share the same identity token without some retrofitting. But this is hitting the limits of my knowledge on the topic of authentication. :) I think our architect's plan was to have the user authenticate separately using the two different identity providers and then only secure the web API using CORS, his reasoning being that since the user is already known and authenticated to use application B, that there wouldn't be any security implications in allowing application A to call application B's web api methods, as the user should be authenticated in application B. This seems quirky to me, in that I can imagine a lot of browser redirects happening that might not be transparent to the user, but other than that, I'm just trying to figure out where the security holes might lie, because it feels to me that there would be some.
I know that this approach would not be considered a best practice, however with that being said, I really want to understand why not. Are there security implications? Would it even work? And if so, are there any "gotchas" or things to consider during implementation?
To reiterate, our lead architect is proposing this solution, and it is failing my gut check, but I don't know enough on the topic to be able to justify my position or else to feel comfortable enough to accept his. Hoping some security experts out there could enlighten me.
It's hard to answer without knowing more on how your current applications and APIs are secured exactly. Do the web application and its API have the same relying party identifier (i.e. can the same token be used to authenticate against both)?
If both web applications use the WS-Federation protocol to authenticate users, then most likely the SAML token will be stored in cookies that were set when the identity provider posted the token back to the application.
You do not have access to these cookies from JavaScript. If the web API that belongs to application B uses the same cookie based authentication mechanism, you could use this provided you allow for cross origin resource sharing.
If your web API uses something like a bearer token authentication scheme (like OAuth) or has a different relying party id in the STS, this would obviously not work.
I think the reason this fails your gut check is because you are basically accessing the web API in a way a cross-site request forgery attack would do it.
A problem I see with this approach is that if the user is not authenticated with the other web application, then the call to your API will also fail.
I agree with user18044 as far as it being based on a cross-site request forgery attack and the security between applications. Is it true that if User X has access to App A, that they will have access to App B and vice versa? If that is not the case, then each application will need to be authenticated separately...and it won't be a SSO. I found these links that might be helpful in your situation.
https://stackoverflow.com/questions/5583460/how-to-implement-secure-single-sign-on-across-various-web-apps
https://developer.salesforce.com/page/Implementing_Single_Sign-On_Across_Multiple_Organizations

How to use OpenID or OAuth for internal first-party authentication?

I am working on an internal authentication system for users of a set of of RESTful web applications. Our intention is that a user should be able to sign-on once via a web form and have appropriate access to all these RESTful applications in our domain, which may be distributed in a private cloud across many servers. (I understand already that having a single authenticated session is not aligned with a pure RESTful approach, but this is a usability requirement.)
The applications themselves will be written in a variety of programming languages so a language-neutral approach is required. It was suggested to me that we might use OpenID or OAuth or a similar framework to handle the authentication but my understanding is that these are intended for third-party services and not the first-party services that would share data on our internal system. In this case, we might have a central provider service with all the other applications treated as third parties (or relying parties).
Questions:
Are OpenID/OAuth suitable for authentication among first-party services?
If so, how would one be advised to set up authentication for this use case?
Wouldn't a user have to grant individual permission to each first-party server that they wanted to use, just as they would need to grant individual permission to any third-party server? I think this would violate the requirement of having a single sign-on for accessing all the first-party services.
Are there good examples of sites supporting this first-party use case?
What would be a good alternative framework for this first-party use case?
You do not need OAuth for SSO services.
The primary use/advantage of OAuth is, as you know already, granting access to a 3rd party app to access/use your resource in a controlled manner.
Rather than having an authentication/authorization server that you would need for OAuth, why not use a single log in service across all your APIs. An OAuth access token is totally different from what you need.
As far as I understand, what you can have is something like OAuth in a way that your server vends out tokens to the app. (I'm assuming that it's a totally internal system, so tokens cannot be misused).
So basically what I'm proposing is:
When an app tries to access the first API it's redirected to a web-form.
The user enters credentials and is taken to the DB for verification. Let there be a service that generates a token for the user/app
Next API access request would be made with that token - the token uniquely identifies the app
Depending on the level of security you need you can sign some text using HMAC and send it as token, or if its totally internal just generate a unique identifier for the app/user and send it to other API
On receiving the token, each service first calls the main server with the token and internally fetches the corresponding customer/user ID and performs the required function.
In short separate the login + token generation + token verification into a different module. All APIs should use this module for login/token verification.
What I have proposed here works like OAuth but all security aspects have been stripped down since you want to use it in a private cloud.
Oauth supports multiple different kinds of flows. You can use the client crendentials flow from Oauth 2.0 to avoid asking the user to grant permission for every app (this is intended for the cases where you control both the server and the app or where you want to preauthorize certain apps). This post does a good job explaining everything: http://tatiyants.com/using-oauth-to-protect-internal-rest-api/