OSEC

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From: Tim Walberg (twalbergmindspring.com)
Date: Fri Sep 14 2001 - 13:42:55 CDT

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    On 09/13/2001 23:13 -0600, Rob 'Feztaa' Park wrote:
    >>
    >> > > [drop fragments rule]
    >> >
    >> > This might not be a great idea, either; the only time fragmented
    >> > packets are insecure is if your firewall doesn't reassemble them
    >> > before inspecting them, and it should be straightforward to configure
    >> > iptables to always reassemble packets before inspecting them.
    >>
    >> Does iptables have a configuration file that would do that? I'm not aware
    >> of one. It doesn't mention any config files in the man page. I was just
    >> skimming, but I also didn't see anything about fragmented packets at all,
    >> except about using -f to drop them.
    >>
    >> So far, I haven't had any problems with this rule, it hasn't prevented me
    >> from connecting to anybody or doing anything... so since it's not hurting
    >> my connection, and it can't possibly make my machine less secure, I say
    >> keep it as-is.
    >>

    IIRC, netfilter (iptables) does this automatically when you have connection tracking
    enabled (modprobe ip_conntrack), which you also need for the stateful inspection
    bit, so chances are you haven't even hit this rule...

                            tw

    -- 
    twalbergmindspring.coM
    

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