OAuth 2 client credentials - oauth-2.0

people!
I'm struggling with building OAuth2 infrastructure in my apps and faced to a problem: where to store client credentials in runtime.
Is there any best practices for delivering client creds to JS SPA for dev/prod environments?
Or hardcode is the only way to make such things?

There are best practices for browser based applications. You cannot store client credentials in a browser - they would become public. You should use Proof Key for Code Exchange (PKCE) instead - creating a secret value that serves as a one time password.

Related

How to exchange JWT tokens across IDP for single page apps?

Trying to understand how multiple IDPs can work together within a SPA.
My initial thoughts
User login with the default IDP and acquire the IDP1-JWT.
When the User needs to Access IDP-2's resources, he accesses through a reverse-proxy over IDP2.
The reverse-proxy send the sub(subject) and sid(session-id) to IDP2.
IDP2 negotiates with IDP1 (openid-connect) to provide the required token.
Reverse-proxy sends IDP2-JWT to IDP2 microservice to enable resource access.
I am still very confused that the above scheme is even sensical, or if there are standard ways to facilitate this kind of exchange. Are there any ways that two OAuth servers can exchange information?
Will this even work for SPA, since IDP2 and IDP-Resource-Server2 would have different domains?
What are the security risks I should look out for?
Thanks
Trying to use Keycloak as IDP2 (which is more under my control) with the steps https://keycloak.ch/keycloak-tutorials/tutorial-token-exchange/#configuring-token-for-an-identity-provider

Questions on OAuth 2 server in ASP.NET Web Api

Currently, I think my understanding of OAuth and how it it is implemented in ASP.NET Web Api is flawed.
1) I keep seeing OAuth described as a server (i.e. the OAuth server). Is the OAuth implementation by a Microsoft a separate server with a different port or is it just referred to as a server even though it is self contained within the API project?
2) Is OWIN separate from OAuth or are the two linked such that they must be used together?
3) How does an OAuth v2 server keep track of tokens that have been revoked or have expired? Does the OAuth component have a database that keeps track of the tokens that it issues? If so, what type of database is it?
I have been reading the tutorials by Taiseer Joudeh from bitoftech.net but I think I am missing some of the basics.
Here are my responses:
You can implement the server as a stand alone authorization server or you can implement it together with the resource server. The Visual Studio template brings you both servers together, but you can separate them. Tutorials from Taiseer Joudeh will guide you very well, they did in my case.
OAuth 2.0 is an authorization framework, as said in its definition document. And OWIN stands for Open Web Interface for .NET. Both of them are different things, but Microsoft decided to do an implementation of OAuth 2.0 protocol using OWIN middlewares architecture. Then the easiest way to develop OAuth 2.0 servers in ASP.NET is using Microsoft.Owin.Security.* libraries implemented by Microsoft.
The OAuth 2.0 protocol does not talk about keeping track of expired or revoked tokens, you could implement if you want, but you only could do if the authorization and resource servers are both the same, and then you will need to access to database to check the token for each request, that it is not necessary. If the resource server is separated from the authorization server it has no direct access to the authorization server database. Normally you don't do that. The expiration check of the token is something that the Microsoft.Owin.Security.OAuth library makes for you. If a token received by the resource server has expired, the library responds with a 401 - Unauthorized response.
To make possible that the resource server can decrypt the token, you only need to set the same machine key in both servers' web.config file.
To avoid to have long lived access tokens you could set short access token timespan and implement refresh token. In this case, you could save refresh tokens in database and you can implement some method to revoke them.
Refresh tokens and its revokation are implemented in Taiseer Joudeh blog posts too.
I hope my explanations are clear and can help you. Please tell me if you have any other doubts.

Client-server user authentication

UPDATE: I failed to mention earlier that we want solution that will be flexible with authenticating users from within our databases or by asking other servers to tell us if the user is authenticated. It is also worth mentioning that these other servers are not under our control so we can't enforce a specific user model.
I had a long and hard read on OAuth and OpenID but they are both not a suitable solution for our situation and will make the process harder to the user. This is something that has been solved a thousand times, yet I cannot find the solution.
What we are looking for is a framework that can be used in a REST services server to authenticate users (no third-party clients involved) with their username and password.
The solution must not pass the username and password except the first time on login and use tokens for further authentication. Even though OAuth does use tokens, it is designed to allow third-party clients access to the service-providers resources. That is not the case here, the services are for our own application only, the only thing needed is user authentication.
What do you guys think is the most appropriate solution?
Configuration:
-Spring server that provides RESTful services with our thinking going towards using Spring Security with some user management and token management framework.
-iOS Device that will be making HTTPS calls to the server.
What we ultimately want is to have the device send a login request and receive a token if the login was successful, later on make requests using that token. Just like Facebook, excluding third-party involvement.
Is there something that is ready to be configured in our server? Or should we consider building our own token management, comparison and generation software?
Is using Spring-Security with an iOS application without involving storing cookies or redirecting to pages possible?
OpenStack offers as part of it's many projects related to open source cloud... the project Keystone. Which does this pretty much exactly what you want.
You might want to check it out here:
http://docs.openstack.org/developer/keystone/

oAuth implementation from the beginning or later

I'm starting a new system creating using .NET MVC - which is a relatively large scale business management platform. There's some indication that we'll open the platform to public once it is released and pass the market test.
We will be using ExtJs for the front-end which leads us to implement most data mining work return in JSON format - this makes me think whether I should learn the OAuth right now and try to embed the OAuth concept right from the beginning?
Basically the platform we want to create will initially fully implemented internally with a widget system; our boss is thinking to learn from Twitter to build just a core database and spread out all different features into other modules that can be integrated into the platform. To secure that in the beginning I proposed intranet implementation which is safer without much authentication required; however they think it will be once-for-all efforts if we can get a good implementation like OAuth into the platform as we start? (We are team of 6 and none of us know much about OAuth in fact!)
I don't know much about OAuth, so if it's worth to implement at the beginning of our system, I'll have to take a look and have my vote next week for OAuth in our meeting. This may effect how we gonna implement the whole web service thing, so may I ask anyone who's done large-scale web service /application before give some thoughts and advice for me?
Thanks.
OAuth 1 is nice if you want to use HTTP connections. If you can simply enforce HTTPS connections for all users, you might want to use OAuth 2, which is hardly more than a shared token between the client and server that's sent for each single request, plus a pre-defined way to get permission from the user via a web interface.
If you have to accept plain HTTP as well, OAuth 1 is really nice. It protects against replay attacks, packet injection or modification, uses a shared secret instead of shared token, etc. It is, however, a bit harder to implement than OAuth 2.
OAuth 2 is mostly about how to exchange username/password combinations for an access token, while OAuth 1 is mostly about how make semi-secure requests to a server over an unencrypted connection. If you don't need any of that, don't use OAuth. In many cases, Basic HTTP Authentication via HTTPS will do just fine.
OAuth is a standard for authentication and authorization. You can read about it in many places and learn; Generally the standard lets a client register in the authentication server, and then whenever this client attempts to access a protected resource, he is directed to the auth-server to get a token (first he gets a code, then he exchanges it with a token). But this is only generally, there are tons of details and options here...
Basically, one needs a good reason to use oAuth. If a simpler authentication mechanism is good for you - go for it.

OAuth 2 provider: storing client credentials

What are the best practices for storing client creds when implementing an OAuth2 provider?
I can store access_token/refresh_token/auth_code as a salted hash (just like passwords) if I decide that every time client requests a new one I issue a new one. But in the case of the client_secret I need to be able to show it along the client_id on the app registration page, so I can't keep only the hash.
Thanks!
Lev
Using a machine generated client secret is only one of many means to authenticate a client application. I assume this is what you want to use in your service. In this case you already answered your question, you have to store the secret in plain text as long as you want to be able to communicate it to application developers at any time.
If this is not acceptable for you, consider choosing a different solution, such as letting the developer set the secret like you would do with a password, and never store the plaintext; or use a private/public key pair authentication scheme like MAC.

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