Yes, probably that's what I saw rather than any more complex rules. Good
tip about using tcpdump to learn what if anything the loopback is doing
over time.

Since it's so easy for an inexperienced user to inadvertently block lo0
with the default rules, it might be worthwhile to add a sentence or two
about this the next time the pf section of the networking FAQ is updated.

Thanks.

//Leigh Engelhart

-------------------------------------------------------------------------------------


The only case where I explicitely use lo0 in rules is to excempt it from
a previous default block rule, as in

  # block everything (on _all_ interfaces) by default
  block in  all
  block out all

  # don't filter the loopback interface
  pass in  quick on lo0 all
  pass out quick on lo0 all

Run tcpdump on lo0 for a week to see what kind of traffic occurs on
there. I never felt the need to restrict it, and blocking it completely
does break things in subtle ways (local dns, mail).

Or did you find an example rule set that actually blocks/allows specific
traffic (certain ports, etc.) on the loopback interface?

Daniel




Reply via email to