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IPTABLE: Whitelist with domains that pulls stuff from other domains

+1 vote
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I wanted to make a white list using the settings below.

iptables -N wanout
iptables -I FORWARD -i `nvram get lan_ifname` -j wanout

iptables -I wanout -m mac --mac-source 01:26:f7:46:71:4b -j ACCEPT
iptables -I wanout -m mac --mac-source d2:37:b5:f2:39:f3 -j ACCEPT

iptables -I wanout -d gamepedia.com -j ACCEPT
iptables -I wanout -d toysrus.com -j ACCEPT

iptables -A wanout -j REJECT --reject-with icmp-proto-unreachable

So the boxes with the MACs specified are exempt from blocking. The domains "gamepedia.com" and "toysrus.com" are accesible to all.

But the problem is that those domains pulls stuff in from other domains using or something, which makes the IPTable block the loading of the website to complete.

How do I deal with that in the best way? I don't want to look up everything they pull in and white list that as well. Also it might change.

Isn't there a way to say "accept all from this domain, even unrelated stuff"?

posted Apr 21, 2014 by Honey

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1 Answer

+1 vote

Linux kernel Netfilter code doesn't have any concept of DNS. When you specify a DNS hostname in your rules, it just does an A record lookup and stores the IP address in your rules.

If you want to employ an HTTP whitelist on Linux, I recommend using a Web Proxy server like squid. It will allow you to do application layer filtering which would be much easier to implement, and more likely to work.

answer Apr 21, 2014 by Garima Jain
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