Netfilter Hooks

[Werner Maier]

Hi,

> Imagine that I want to create a filter, that blocks/allow every packet
> that contains the word, for example, "GOOGLE" in it. I don't want to
> block a packet deriving from some IP, or something like that, I want
> to filter the content. For example, be able to parse a XML file in a
> packet, or parse some protocol, something like that.

look for "string" in the manpage to iptables.

iptables ... -m string --string "GOOGLE" --algo bm ...

should be the right pointer for you.

regards

Werner Maier
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Werner Maier, Dipl.-Ing. Univ.         Friedrich-Bergius-Ring 15
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