Re: Request for comments: iptables script for use on laptops.

[Rolf Kutz <kutz@netcologne.de>]

* Quoting Uwe Hermann (uwe@hermann-uwe.de):

> >   iptables -A INPUT  -j ACCEPT -s 127.0.0.1      # local host
> >   iptables -A OUTPUT -j ACCEPT -d 127.0.0.1
> 
> Correct me if I'm wrong, but I think this would also allow incoming
> traffic from 127.0.0.1 to the eth0 interface. So somebody spoofing
> his IP address to appear to be 127.0.0.1 could send _any_ traffic
> to you and you would ACCEPT it, basically rendering the firewall
> useless. Did I miss anything?

Maybe this:

| echo 1 > /proc/sys/net/ipv4/conf/all/rp_filter

-  Rolf