Add temporary rule to Iptables

rickh · 03-04-2008, 08:21 AM

I don't have extreme needs for a Firewall. I have the hardware firewall on my router, backed up by Firestarter. My iptables rules are set up by Firestarter. This is an excerpt from "# iptables -L -n"

Code:

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Chain INBOUND (1 references)
target     prot opt source               destination         
ACCEPT     tcp  --  0.0.0.0/0            0.0.0.0/0           state RELATED,ESTABLISHED 
ACCEPT     udp  --  0.0.0.0/0            0.0.0.0/0           state RELATED,ESTABLISHED 
ACCEPT     all  --  192.168.123.0/24     0.0.0.0/0           
ACCEPT     tcp  --  0.0.0.0/0            0.0.0.0/0           tcp dpts:6696:6699 
ACCEPT     udp  --  0.0.0.0/0            0.0.0.0/0           udp dpts:6696:6699 
LSI        all  --  0.0.0.0/0            0.0.0.0/0 
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For the current session only, I wish to also block a specific IP address (1.1.1.1). I assume that I can do that using the iptables command to add the rule, but...

Code:

debian64:~# iptables -A INBOUND DROP       all  --  1.1.1.1/0             anywhere
Bad argument `DROP'
Try `iptables -h' or 'iptables --help' for more information.

debian64:~# iptables -h
iptables v1.4.0

Usage: iptables -[AD] chain rule-specification [options]
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What am I doing wrong?

acid_kewpie · 03-04-2008, 08:25 AM

well that's not an iptables command... that you copying the verbose output and pasting it back in... big mistake!

iptables -A INPUT -s 1.1.1.1 -j DROP

also note that if that was a valid command, you would be blocking 1.1.1.1/0 which is identical to 0.0.0.0/0 i.e. *everything*!

rickh · 03-04-2008, 08:29 AM

It's not really 1.1.1.1 I wish to block, I just put those numbers in as an example. Thanks for the advice, I'll try doing it correctly.

Edit:Amazing how easy it is if you know what you're doing. Thanks again.

acid_kewpie · 03-04-2008, 10:10 AM

Well yes of course, but i meant that any.ip.at.all/0 == 0.0.0.0/0 == everything