Black Hole Routes

Has anyone worked on a policy for generating black-hole routes? I'd
like to set up an automatic process for feeding host routes directly
from bro into my quagga route server. I'm thinking a simple broccoli
script would do the trick, with some judicious use of expect to talk to
the quagga bgpd CLI. However, I'd like to build on others' experience,
and perhaps build something more generic we can all use.

drop.bro hooks into a drop-connectivity and restore-connectivity script to do this, by calling drop-connectivity with the address as an argument, and with a "catch and release" restore policy.