Security....

[James Kosin]

Rodolfo J. Paiz wrote:

> <<-- snip -->>
>
>I love it.
>
>  
>
I took a simpler approach.

1.  Setup iptables with the following
    iptables -A INPUT -i lo -j ACCEPT   # this allows local loop 
interface to always work.
    iptables -A INPUT -d xxx.xxx.xxx.xxx -m state --state 
RELATED,ESTABLISHED -j ACCEPT   # accept connections back to this host 
for connections attempted from this host
    iptables -A INPUT  -j REJECT         # this rejects everything else

2.  I just add
    iptables -I INPUT 3 -d xxx.xxx.xxx.xxx -p tcp -m state --state NEW 
-m tcp --dport yyy -j ACCEPT
    for each port I want to open up on my server.

Note:   xxx.xxx.xxx.xxx gets replaced with the local machine's IP address.
            yyy gets replaced with the port number

You can also restrict the source IP address for the packet by including 
a -s zzz.zzz.zzz.zzz to the iptables command.

Most clients, #1 above is enough to block all attacks.

James Kosin