Grails Spring Security plugin Access Control/Authorization without Authentication?

3
votes

My problem:

I would love to use the Spring Security plugin's access control/authorization mechanism with my Grails application without having to use the plugin's authentication mechanism. The various Grails Spring Security plugin examples (like this one) I've found combine these two functions. Is there an easy way to just do access control?

Background:

  • I would like to add roles-based access control to my existing app. I would love to either just annotate my controllers or use the Config.groovy map approach for setting up the access control.
  • My app already has a user domain class.
  • The user domain class already handles encrypting passwords using BCrypt.
  • The app does not have a "role" domain class.
  • I already have controller actions, views and business logic for handling logging in and logging out. I have no interest in replacing this with the plugin's implementation.

On the right track, but not quite helpful:

I know this is possible to do, as explained in this other question: BUT, that questions and its answers explains how to do it in a Java app using the raw Spring Security framework. I would love for someone to lay out how to do this in a way that is compatible with the latest version (1.2.7.3 as of this writing) of the Grails Spring Security plugin. I don't want to reinvent wheels that have already been taken care of by the plugin.

In addition, this example explains how to do some of this, but it appears to be outdated because it is based on an older version of the plugin that uses Spring Security 2.x. It also only uses custom authentication for one piece of the app, while it looks like it still uses the Spring Security plugin's domain classes elsewhere.

How to do it?

Can someone lay out an approach for me? I assume I need to create my Role domain class. After that I assume it will involve custom Authentication objects and the like. But how do I hook them into use the plugin's existing code?

2
grailsspring-security

2 Answers

3
votes

You could go with a custom authentication provider and I have an updated version that I did as part of a recent talk. See this blog post which has a sample app and link to a video of the talk: http://burtbeckwith.com/blog/?p=1090

It would be simple to use a custom UserDetailsService - this is the most common customization done for the plugin and it so has its own chapter in the docs: http://grails-plugins.github.com/grails-spring-security-core/docs/manual/guide/11%20Custom%20UserDetailsService.html

Basically you need to create a Spring Security User instance and Spring Security (and the plugin) doesn't care how you get the data. So your custom UserDetailsService just needs to be a bridge between your current auth scheme and Spring Security.

1
votes

I ended up creating my own access control/authorization mechanism rather than using the Spring Security plugin. I never could figure out how to separate the plugin's authentication mechanism from the authorization mechanism. Doing the work myself was very easy.

I did the following:

  • Created a new Role domain class.
  • Added a Set property and hasMany relationship to my User domain class.
  • Created a new AuthorizationFilters filter. This is where I put in my authorization rules. In this filter I can check to see if a user has the role necessary to access the given URL and redirect to a login page, redirect to a "not authorized page" or allow them to pass.

This doesn't have the nice syntactic sugar of the plugin and isn't quite as concise either, but it was very easy to implement and understand.