external libs with kernel driver

Hi everyone,

I don't have much experience in linux programming but I wondered if it 
would make sense to split click up into a user level part and a kernel 
level part and let the both communicate through a netlink-socket. Or 
would that be a bottleneck? As I understand it the kernel level mode 
brings performance at cost of flexibility (not possible to use external 
libraries).
Background: I tried to use the Botan crypto library but it will only 
work in unserlevel.

I would be very pleased for a comment,

cheers

Joerg Kaiser