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Re: ipf rules for dial-up system

Charles Calthrop wrote:
> Hi there,
> I'd like to implement some filtering rules in my OpenBSD system at home,
> which has dial-up access to the net. Basically, I would like to
> deny access to all incoming connections while not interfering with
> outgoing ones.
> Anyone cares to share some ipf rules suitable for this task?

replace ppp0 with your interface name if it's different. Replace with your internal netblock

block in log quick on ppp0 from any to any head 01

block out log on ppp0 from any to any head 02
pass out quick on ppp0 from to any proto tcp keep state
group 02
pass out quick on ppp0 from to any proto udp keep state
group 02
pass out quick on ppp0 from to any proto icmp keep state
group 02

This should work, provided you don't want to use active ftp
(passive-mode will work fine though).

Rather than follow this, read:

- Aidan

Aidan Skinner
Reality Group Ltd
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