First of all I just want to mention that I haver really bad knowledge of this topic. But my problem is that I have an grafana-instance running in openshift that is using oauth-proxy for authentication.
On my company we are using a Kerberos-solution to automaticly authenticate users accessing company domains. The problem is that we want to manage what groups that have access to the grafana-instance and if possible authenticate in the background without the users having to enter any usernames/passwords.
As I understand the current kerberos solution works like this:
User -> company.com -> SSO-server -> [fetch user from LDAP] -> If Authenticated, Redirect to company.com
Is it somehow possible to do something similar:
User navigates to grafana.company.com
grafana.company.com redirects to sso-server
Magic kerberos authentication occurs
Redirects back to grafana.company.com
someway authenticates the user directly from grafana or oauth-proxy
It is possible; any web-based SSO system that asks you for username/password can instead ask for a Kerberos ticket at the same point. (The latter is done using HTTP-level "Negotiate" authentication, also known as "SPNEGO".) Once the SSO system has established your identity, it'll happily issue the same OIDC or SAML tokens regardless of what kind of authentication was used.
For example, the Keycloak OIDC IdP has built-in support for HTTP Negotiate; search the docs for "SPNEGO". Shibboleth IdP (for SAML) has SPNEGO support as well.
Also, any SSO system that supports getting the 'REMOTE_USER' assertion from the web server (instead of using its own credential prompts) can be used with Kerberos, using e.g. Apache mod_auth_gssapi or Nginx spnego-http-auth modules.
Related
How do I best configure Keycloak so that a user needs to have an account for a client to be able to login into that client?
I have to replace a proprietory SSO-Impl. It deals with users, roles and clients much like Keycloak. However, it also knows about accounts. A user is only allowed to login to a client if he has an account for that client.
In Keycloak, if a user simply exists in a realm he may login to a client of that realm. Nothing else is needed. So no "account" is needed. In the old application, he needs an account as well.
What functionality in Keycloak is best suited to overcome this difference?
I have one idea:
Create a client-role in each client namend "HasAccount" and assign it to users. Then, restrict access if that role is missing.
This is discussed here: "Restrict client access in a single realm with keycloak"
It has at least two drawbacks:
It mixes authentication and authorization in the legacy app. I can understand that. But creating a role was already a workaround. That is why I described my initial problem here.
I have clients in 3+ languages/technologies. Adding functionality there seems like more work than in Keycloak.
Last remark:
Before you ask "This is not single sign on" anymore. It is only for administrative purposes. The admin can allow users to login into a client or not by creating an account or not. The user does not have to login a second time. If he is logged in in App A and has an account for App B, accessing App B works without logging in there.
A user is only allowed to login to a client if he has an account for that client. is really not a task for Identity Provider (IdP). It provides only identity and not authorization.
Of course you can ignore that and implement authorization as well. See: User attribute based web service access control by Keycloak
From the design perspective I would add auth reverse proxy in front of legacy app (but it isn't a best solution for SPA apps). Auth proxy will provide authentication via OIDC protocol and also authorization. Legacy apps may keep own OIDC authentication - it will be seamless auth from the user perspective, because SSO will be used.
Account entity - you can use group entity in the Keycloak instead of original account.
Is opening a browser to display a login page, which was generated from the site performing the authentication, built into the OAuth2 specification?
My requirements and constraints are going to prevent me from having a browser on the device. However, a request to authenticate the user against Azure Active Directory has been made. They are really looking for the desktop application to have fields in its own GUI for the username and password, and the ability to check if that's a registered user or not.
Is opening a browser to display a login page, which was generated from the site performing the authentication, built into the OAuth2 specification?
It is related to used OAuth2 flow specification, not to OAuth2 specification.
My requirements and constraints are going to prevent me from having a browser on the device.
That means you can't follow RFC8252 (where that browser is required).
So your only option is Resource Owner Flow/Direct Access Grant. But it isn't "secure", because app will have access to user credentials. Other cons: single sign-on won't be working, some IDPs may have also problem with multi factor authentication for this flow and security enterprise departments also don't like this flow at all usually.
I am exploring keycloak for my project SSO solution, and I am trying the open-connect on this blog https://developers.redhat.com/blog/2017/05/25/easily-secure-your-spring-boot-applications-with-keycloak/
And I would like to as one question about Single Sign Out, I would like to know what’s the principle behind. Tried to search online document but I didn’t find any clue .For a while, I was thinking there is no elegant solution for Single Sign Out in oauth2 world.
This is the way Keycloak implements it (yes, this is not part of OAuth):
when you use Keycloak to create a server side session in your application using the Java Client, Keycloak will trigger a logout of the session once the logout at Keycloak is triggered. You'll need to set up an Admin URL for your application in Keycloak. This is called "backchannel logout" in the documentation.
When you use Keycloak in a HTML5 client, Keycloak will create a hidden IFRAME that will check that the Keycloak-Cookie is still present. If it is not, the HTML5 application knows that you have been logged out.
OpenID Connect Back-Channel Logout seems to be the way to go nowadays. It works by exposing a special end-point in your application (backchannel_logout_uri), which will be invoked by the OpenID Provider when the user logs out from SSO. Through this endpoint, the Provider gives you a signed Logout Token, to notify your application that the user's session should be terminated.
Because a user may be logged in from multiple devices, browsers, etc., the OpenID Provider can also include a Session ID (sid claim) as part of the Logout token. You can compare it with the sid that you would have received in the ID Token during login, to decide which session to terminate.
The standard back-channel logout was implemented in Keycloak 12.0, which shipped in December 2020. Earlier versions only implemented an alternative, proprietary mechanism.
I'ld like to implement SSO using SAML 2.0 in my web applications. I have seen spring-security-saml example [https://github.com/spring-projects/spring-security-saml.git]. There are a couple of things I wanted to know after I went through this sample:
Do I have to redirect all the user-registratons to the registration page of IDP as in this sample ? If not, how does the IDP know the credentials of the user?
Do the IDPs' like ssocircle (used in this sample) allow us to use customized attributes and change password kind of scenarios ?
What is the best IDP to use to implement saml sso in my application ?
Thanx in advance.
Q. Do I have to redirect all the user-registratons to the registration page of IDP as in this sample?
In SAML parlance, an application can be an identity provider (IDP) or a service provider (SP). An IDP authenticates users, which means that user identities and credentials are maintained by the IDP. An SP provides one or more service to the user.
From your question, it seems that you want to delegate the task of authenticating users of your application to an external party (the IDP). Therefore, your application will be the SP.
With that established, you will have to redirect all users to the IDP for authentication. The IDP's authentication page may have a link to the registration page, if required.
Q. How does the IDP know the credentials of the user?
The user must be registered with the IDP (after all, the purpose of the IDP is to authoritatively authenticate a user's identity, which it cannot do if the user is not registered with it). Users can be self-registered or registered by an administrator, such as, a Microsoft Active Directory Domain Administrator.
Q. What if I need to register the user in my system as well since I need to assign them roles specific to my system?
You can create your own implementation of org.springframework.security.web.authentication.SavedRequestAwareAuthenticationSuccessHandler wherein you can check the authenticated user on successful single sign-on and register them with your application. Supply an instance of your implementation class as the redirect handler to the SAML entry point.
Do note that you will not have access to the user's password since that is stored by the IDP.
Q. Do the IDP's like SSOCircle allow us to use customized attributes?
SSOCircle is mostly a testing service for SSO (single sign-on). Although SAML supports custom attributes, SSOCircle only supports FirstName, LastName and EmailAddress (as of February 2016). Therefore no, you cannot use other custom attributes with SSOCircle.
Actual IDP's like Okta, OneLogin or Microsoft ADFS do support custom attributes. You must check their respective documentation for configuring and exchanging custom attributes between the IDP and the SP.
Q. Do the IDP's like SSOCircle support change-password kind of scenarios?
I am not sure about SSOCircle but an actual IDP will be a system that already has user identity management capabilities. Since password change is a common functionality for an identity management system, this should be supported with an actual IDP. However, you should consult the documentation for the actual IDP you use to make sure.
Q. What is the best IDP to use for my SAML application?
An IDP is not a product or a specification, making this question somewhat invalid. It is simply a type of actor in the SAML universe. If your users are part of a Microsoft Windows Active Directory forest, you can use Active Directory Federation Services (ADFS) to exchange SAML messages between Active Directory and your (SP) application(s).
If you want to support multiple Active Directory forests, or if you do not know in advance where your users will be, you can use delegation-based services like Okta or OneLogin, which allow your application to take incoming assertions from the delegation service.
Before you put me down for asking too basic a question without doing any homework, I'd like to say that I have been doing a lot of reading on these topics, but I'm still confused.
My needs seem simple enough. At my company, we have a bunch of Ruby on Rails applications. I want to build an SSO authentication service which all those applications should use.
Trying to do some research on how to go about doing this, I read about CAS, SAML and OAuth2. (I know that the "Auth" in OAuth stands for authorization, and not authentication, but I read enough articles saying how OAuth can be used for authentication just fine - this is one of them.)
Could someone tell me in simple terms what these 3 are? Are they alternatives (competing)? Is it even right to be comparing them?
And there are so many gems which all seem to be saying very similar stuff:
https://github.com/rubycas/rubycas-server and https://github.com/rubycas/rubycas-client
https://github.com/nbudin/devise_cas_authenticatable
https://github.com/onelogin/ruby-saml
CASino and https://github.com/rbCAS/casino-activerecord_authenticator
And I am sure there are hundreds of OAuth related gems.
I just want a separate Rails application which handles all the authentication for my other Rails apps.
Note: I do not want to allow users to use their Google / Facebook accounts to login. Our users already have accounts on our site. I want them to be able to login using that account once and be able to access all our apps without signing in again. Signing out in any app should sign them out of all apps.
UPDATE
I have come across these two OAuth solutions:
http://dev.mikamai.com/post/110722727899/oauth2-on-rails
http://blog.yorkxin.org/posts/2013/11/05/oauth2-tutorial-grape-api-doorkeeper-en/
They seem to be describing something very similar to what I want. But I haven't found any guide / blog post / tutorial showing how to do this with SAML / CAS.
Suggestions welcome.
UPDATE 2
More details about our use-case.
We do not have any existing SAML architecture in place. Primarily, it is going to be OUR users (registered directly on our website) who are going to be accessing all our applications. In the future, we may have third-party (partner) companies calling our APIs. We may also have users from these third-party (partner) companies (registered on their websites) accessing our apps.
CAS-Server:
A stand-alone central login page where the user enters their credentials (i.e. their username and password).
CAS supports the standardized SAML 1.1 protocol primarily to support
attribute release to clients and single sign-out.
(a table in a SQL database, ActiveDirectory/LDAP, Google accounts, etc.)
Full compatibility with the open, multi-platform CAS protocol (CAS clients are implemented for a wide range of platforms, including PHP, various Java frameworks, .NET, Zope, etc.)
Multi-language localization -- RubyCAS-Server automatically detects the user's preferred language and presents the appropriate interface.
SAML :
Security Assertion Markup Language is an XML-based, open-standard data format for exchanging authentication and authorization data between parties, in particular, between an identity provider and a service provider.
SAML authorization is a two step process and you are expected to implement support for both.
OAuth 2.0:
The OAuth 2.0 authorization framework enables a third-party
application to obtain limited access to an HTTP service, either on
behalf of a resource owner by orchestrating an approval interaction
between the resource owner and the HTTP service, or by allowing the
third-party application to obtain access on its own behalf.
Important Note :
SAML has one feature that OAuth2 lacks: the SAML token contains the user identity information (because of signing). With OAuth2, you don't get that out of the box, and instead, the Resource Server needs to make an additional round trip to validate the token with the Authorization Server.
On the other hand, with OAuth2 you can invalidate an access token on the Authorization Server, and disable it from further access to the Resource Server.
Both approaches have nice features and both will work for SSO. We have proved out both concepts in multiple languages and various kinds of applications. At the end of the day OAuth2 seems to be a better fit for our needs (since there isn't an existing SAML infrastructure in place to utilize).
OAuth2 provides a simpler and more standardized solution which covers
all of our current needs and avoids the use of workarounds for
interoperability with native applications.
When should I use which?
1.If your usecase involves SSO (when at least one actor or participant is an enterprise), then use SAML.
2.If your usecase involves providing access (temporarily or permanent) to resources (such as accounts, pictures, files etc), then use OAuth.
3.If you need to provide access to a partner or customer application to your portal, then use SAML.
4.If your usecase requires a centralized identity source, then use SAML (Identity provider).
5.If your usecase involves mobile devices, then OAuth2 with some form of Bearer Tokens is appropriate.
Reference 1,Reference 2,Reference 3
If you need to authenticate for LDAP or ActiveDirectory then a solution like one of the CAS gems you mentioned above is right for you (RubyCAS, CASino).
If you can afford it, one of the commercial vendors (like Okta) is your best option because they will stay on top of security patches and manage your authentication needs for you. In particular, if you have to support ActiveDirectory, they've already implemented it.
OAuth is most useful for third party authentication, though it can do SSO. So if you wanted to support Google / Facebook logins or be a third party authenticator then it's a great choice. Since you don't want to support Google / Facebook then OAuth is probably not what you want.
If you are only intending to use HTTP POST for your SSO needs then the ruby-saml gem could be the way to go. You would have to implement your own Identity provider and add a service provider component to all your websites (possibly in the form of a gem.) Part of what you would need is a rails api to act as your identity provider. This gem helps support writing API's in rails.
EDIT
You mention the possibility that future third party users might be logging on to your site. This changes your calculus away from rolling your own ruby-saml solution.
The best way to share your authentication API is to implement an OAuth layer. Doorkeeper is a popular solution and is fast becoming the standard for Rails authentication. It's community support, flexibility and ease of use make it the best way to go for a consumable authentication API.
Railscast for implementing doorkeeper
Anjan.
I've used CAS and OAuth in my work. Here are some of my opinions, and hope to help.
Basically
Both CAS and SAML aim to solve SSO situation. And CAS is a service or an authentication system, which can support SAML protocol.
OAuth aims to solve authorization and authentication.
And in practice,
Both CAS and SAML act as an gateway in front of a group of applications which belong to one organization. Just like your case.
OAuth is used to authorize and authenticate between different organizations.
Just my thoughts, and hope to hear more voices.
We have used CAS and SAML in our architecture (Mobile App, Online Portal, and MicroServices) and both are used for different purpose.
Our Online Portal is like online banking that runs in public domain and has to be secure. We don't want to store password and other secure token's in the DB of the online portal, therefore, we use CAS for authentication and authorization. During registration, when user chooses the password, we store the password in CAS and store corresponding token in the DB of Portal
When user login next time, User enters the user name and password in Portal. Portal fetches the token corresponding to user from DB and sends User_name, password, and token to CAS for validation.
But, in case user has already logged in into one application and we redirect user to our another application then we dont want to user to enter username and password again for second application. We use SAML to solve this. First application shares user details with SAML server and gets token in return. First application passes the token to second application. Second application sends token to SAML server to get user details and on success lands user to desired page. Our first application can be Mobile App and second can be Portal in the scenario of App2Web.
Since you have got lot of answers for this question, I would like to suggest you an identity product that can be cater these kind of all protocol in one hand with lot of authentication and user management features. You can just try WSO2 Identity Server version for this.