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On Sat, 12 Dec 2015 01:29:20 -0500 waltdnes@××××××××.org wrote: |
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> On Fri, Dec 11, 2015 at 08:03:14PM -0700, thelma@×××××××××××.com wrote |
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> > Does anybody have an idea how to block facebook? |
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> > |
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> > I'm using dd-wrt. The "access restriction" can block http but not https |
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> > and I'm not good in iptables :-/ |
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> > In addition users are using VirtualBox on the network as well. |
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> |
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> An excerpt from my /var/lib/iptables/rules-save ruleset... |
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> |
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> [0:0] -A INPUT -s 31.13.24.0/21 -j FECESBOOK |
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> [154:11168] -A INPUT -s 31.13.64.0/18 -j FECESBOOK |
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> [0:0] -A INPUT -s 66.220.144.0/20 -j FECESBOOK |
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> [0:0] -A INPUT -s 69.63.176.0/20 -j FECESBOOK |
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> [0:0] -A INPUT -s 69.171.224.0/19 -j FECESBOOK |
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> [0:0] -A INPUT -s 74.119.76.0/22 -j FECESBOOK |
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> [0:0] -A INPUT -s 103.4.96.0/22 -j FECESBOOK |
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> [0:0] -A INPUT -s 173.252.64.0/18 -j FECESBOOK |
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> [0:0] -A INPUT -s 204.15.20.0/22 -j FECESBOOK |
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> |
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> [0:0] -A OUTPUT -d 31.13.24.0/21 -j FECESBOOK |
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> [3763325:225839770] -A OUTPUT -d 31.13.64.0/18 -j FECESBOOK |
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> [56:3360] -A OUTPUT -d 66.220.144.0/20 -j FECESBOOK |
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> [0:0] -A OUTPUT -d 69.63.176.0/20 -j FECESBOOK |
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> [874:52440] -A OUTPUT -d 69.171.224.0/19 -j FECESBOOK |
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> [0:0] -A OUTPUT -d 74.119.76.0/22 -j FECESBOOK |
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> [0:0] -A OUTPUT -d 103.4.96.0/22 -j FECESBOOK |
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> [3306:198360] -A OUTPUT -d 173.252.64.0/18 -j FECESBOOK |
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> [0:0] -A OUTPUT -d 204.15.20.0/22 -j FECESBOOK |
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> |
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> [3767715:226105098] -A FECESBOOK -j LOG --log-prefix "FECESBOOK:" --log-level 6 |
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> [3767715:226105098] -A FECESBOOK -j DROP |
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|
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+1. Just block their CIDR ranges. No need to do DPI like was |
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suggested here. Of course smart users can use proxies or tunneling, |
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so this is not 100% solution, but for the majority it will work. |
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|
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Just a tip here: use ipset hash:net for all this ranges and just a |
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few iptables rules to check src and dst in FORWARD and/or |
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INPUT/OUTPUT depending on whether host is router or target system, |
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e.g. for dd-wrt will be sufficient: |
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|
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iptables -A FORWARD -m set --match-set facebook src -j DROP |
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iptables -A FORWARD -m set --match-set facebook dst -j DROP |
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|
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A set can be created like this: |
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|
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ipset create facebook hash:net |
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ipset add facebook 31.13.24.0/21 |
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... |
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|
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Of course logging may be enabled as above if desired. |
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|
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This way filtering will be much faster and blocklist may be updated |
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without touching iptables rules. Gentoo init script support ipset |
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rules save/load as well as iptables. |
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Do not forget about ipv6 if it is enabled on your network. |
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|
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Best regards, |
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Andrew Savchenko |
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