Get HTTP Request in Elytron JAAS Login Module

Hello,

i am using jboss8 - beta with the Elytron subsystem with a JAAS -Realm.
(Like in this example: Github Example ) .
The example is working fine, but i have an extra requirement.

I need to get Information out of the http-Request as ( HttpServletRequest Object in my JAAS LoginModule to use it for authentication purposes .

(In WebLogic this was achievable with an Identity Asserter)

How is this possible?

Thanks in advance for any advice.