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On Mon, 2010-04-05 at 19:32 +0200, Jarry wrote: |
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> Hi |
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> |
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> I'd like to ask if there is some way to include multiple discrete |
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> hosts/IP's in --source and --destination options of iptables. |
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> |
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> I'm trying to write firewall rules for my server, but it has |
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> 12 IP's from different segments (and maybe it gets a few more |
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> later), and the script grows up as I have to write nearly |
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> identical rules with difference only in -s/-d IP's. |
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> |
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> What I'm looking for is a way to define some variable at the |
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> beginning of my script, like MY_IP="IP1 IP2 IP3 IP4..." and |
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> later to use is in rules (iptables -A INPUT -s $MY_IP...). |
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> But I do not know how to use it. As far as I understand it, |
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> --source/--destination accepts only single IP's or continuous |
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> IP-segments... |
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|
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You can do something like: |
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(100) iptables -N IP_SET_CHECK |
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(110) iptables -A IP_SET_CHECK -s $IP1 -j RETURN |
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(120) iptables -A IP_SET_CHECK -s $IP2 -j RETURN |
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(130) iptables -A IP_SET_CHECK -s $IP3/16 -j RETURN |
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(140) iptables -A IP_SET_CHECK -s $IP4 -j RETURN |
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(150) iptables -A IP_SET_CHECK -j DROP |
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|
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(210) iptables -A INPUT -j IP_SET_CHECK |
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(220) iptables -A INPUT some other rules.... |
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(230) iptables -A INPUT some other rules.... |
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|
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So, when it comes to the the line 210, it will start checking newly |
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created chain IP_SET_CHECK. If it won't find appropriate rule it will be |
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dropped at the line (150), but if manages to find one, it will return to |
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the line 220 and will continue looking for "-j ACCEPT" or "-j DROP". |
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|
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The same applies for the OUTPUT chain. |
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|
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> Jarry |
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> |
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