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Re: iptables not so stateful



Eric Gaumer <gaumerel@titan.ecs.fullerton.edu> writes:

> Then you have a bunch of high end ports open. Connection tracking
> doesn't work with active FTP because it is a server initiated
> connection. 

Check out the iptables documentation page.
"RELATED

    A packet which is related to, but not part of, an existing
    connection, such as an ICMP error, or (with the FTP module
    inserted), a packet establishing an ftp data connection."

This is in connection with the state option for iptables.  Active ftp
works with connection tracking, and I've tried it.

> That's one of the main reasons passive exists. If the server
> picks a port at random, then there is no way the client can anticipate
> what port to open. 

passive exists because of some firewall (like the older ipchains) didn't
have connection tracking.

Check out this website too:
http://www.sns.ias.edu/~jns/security/iptables/iptables_conntrack.html

-- 
John L. Fjellstad
web: http://www.fjellstad.org/          Quis custodiet ipsos custodes



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