I am supposed to create a security application for linux. Basically once the file is open i have to read somethin and on the basis of that i give the user permissions. In windows this was implemented using somethin called a filter driver. In linux i know this can be done by adding some code to the kernel and then creating patch. But i dont want this. It has to be like package or something. How exactly can this be done?? Just want some basic ideas for a start.