I have an MVC application (.Net Framework 4.5) which is been there for the last three years and using Forms Authentication mechanism. This application provides different accounts like Personal, freebie, Enterprise etc. For an enterprise account, we are handling everything in the same application. I.e. Suppose an enterprise called “xyz” created an enterprise account with the application, then we are providing a custom URL like “https://application/xyz/login” and from the URL we are identifying that enterprise. I don’t know the exact reason why they implemented like this as I have seen applications that are having enterprise accounts are created as subdomains (e.g. https://xyz.okta.com). Now the client asked to integrate Okta into this application. So I looked into Okta and found SAML is the right way to do and ends up in KentorIT Authservices. Initially, I was able to integrate this with a sample MVC application and the authentication part was working fine. With some basic idea about SSO, I have started integrating kentor authsevices into my application. The challenges I found in this implementation are:
1) For Enterprise accounts, Okta configuration settings are different for each enterprise and with my current application implementation, it is not possible to set it in from the web.config. So I have tried to set it from code and I was able to integrate those settings by replacing Configuration.Options.FromConfiguration;. I’m planning to store all configuration related things(Single sign-on URL, Audience URI,Identity Provider Issuer" etc.) in the database so that I can get the information whenever I wanted and I’m assuming that “Identity Provider Issuer Id is unique for each Okta account. In an IdP initiated flow, when the user tries to access the application it will redirect to AuthServices\Acs action method and from that, I’m trying to read the configuration settings. From the request is there any way I can identify from which Okta account call came(like Identity Provider Issuer)? Currently, I set the "Identity Provider Issuer" value (and I think which should be unique for okta account) to the Default RelayState field under General SAML settings tab and I was able to retrieve it from AuthServices\Acs action methods. Does it seem to be a good idea? Please advice.
2) The Enterprise accounts are limited based on the number of licenses (say 50). Suppose if the Enterprise Okta admin intentionally added 55 users all those users can successfully authenticate the application based on the default settings. Is there any way I can handle this scenario. Do I need to keep a record of the list of users that came under a particular enterprise account?
3) From the documents I understand that Kentor authentication service is only for authentication and authorization part has to be done from the application itself. The current application implementation consists of a custom authorization attribute which checks for user permissions that are stored in the database. That should be there as it is and we have to do the authorization based on database permissions. Right?
Expecting your valuable suggestions and please correct me if I'm wrong. Thanks in advance.
Don't use the RelayState for sensitive data unless you cryptographically sign it. It is not protected by any signature when using the POST binding, so the user may manipulate it. To get the issuing idp, check the issuer field of any claim generated by AuthServices instead.
Yes.
Yes, that's the whole idea with Kentor.AuthServies: To plug SAML2 authentication into the security model of .NET to allow you to use any current/traditional Authorization setup.