Suricata

To be able to automate the configuration of frag and stream policy,
I propose that it is possible to read such info of IP and OS from a file.

It might be simple:
192.168.10.123|linux
192.168.10.124|vista
10.10.200.1|bsd

Or one could look at snorts host_attribute table.
Info on IP<->OS can be fetched from an inventory DB or Hooger and PRADS etc.

(
http://code.google.com/p/hogger/
https://github.com/gamelinux/prads/
)