Luis,
You'd be use FORWARD chain in the table filter.
POSTROUTING and PREROUTING is in the nat table.
# The first rule allow traffic in port tcp/80
/sbin/iptables -A FORWARD -s 12.16.2.5 <http://12.16.2.5> -p tcp --dport
80 -j ACCEPT
# The second rule allow the trafic inbound to 12.16.2.5
<http://12.16.2.5> source from port tcp/80.
/sbin/iptables -A FORWARD -d 12.16.2.5 <http://12.16.2.5> -p tcp --sport
80 -j ACCEPT
# The third rule drop all trafics in all ports and protocols.
/sbin/iptables -A FORWARD -s 12.16.2.5 <http://12.16.2.5> -j DROP
Best Regards,
Diego Lilioso
2008/10/16 James Shupe <shupej@hermetek.com <mailto:shupej@hermetek.com>>
Correction:
[QUOTE]
You'd be better off with a DROP policy where you could just use:
/sbin/iptables .... -d $EXTERNAL_HOST -p 80 -j ACCEPT
With your ACCEPT policy, just use inverse:
/sbin/iptables .... -d ! $EXTERNAL_HOST -p 80 -j DROP
[/QUOTE]
"-p 80" needs to be "-p tcp --dport 80". Not sure how I overlooked it.
-
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On Thu, 2008-10-16 at 15:27 -0400, Luis Rondon Paz wrote:
> hello everyone i have a question
> i have this in my iptables
>
> EXT_IF=eth1
>
> #############
> /sbin/iptables -t nat -A POSTROUTING -s 12.16.2.5
<http://12.16.2.5> -o $EXT_IF -j MASQUERADE
>
>
> now
> how can i DROP ALL TRAFIC FROM IP 12.16.2.5 <http://12.16.2.5>
??? exept port 80 to one
> external ip ?
>
> example
>
> i neeed to drop all traffic
> and i need to allow the traffic to one address only
>
> how can i do that Ç????
>
>
> /sbin/iptables -t nat -A POSTROUTING -s 12.16.2.5
<http://12.16.2.5> -d EXTERNALONEHOSTONLY
> -o $EXT_IF -j ACCEPT
>
> /sbin/iptables -t nat -A POSTROUTING -s 12.16.2.5
<http://12.16.2.5> -d 0.0.0.0/0 <http://0.0.0.0/0> -o $EXT_IF
> -j DROP ???
>
>
> OR SHOULD I NEED TO USE TO FORWARD ??
>
> thanks for reading me .
>
>
>
>
>
>
>
>
>