Re: Iptables FTP question

From: David (
Date: 10/27/03

  • Next message: GuitarMan: "Re: Duane Arnold to star in "Chimpie in the mist""
    Date: Mon, 27 Oct 2003 22:50:43 GMT

    You would only need RELATED set in your rule for port 21 if you were
    allowing it to deal with related ICMP traffic for the control
    connection. And since you put -p tcp in your rule it will not deal with
    any related ICMP anyhow. As far as the ftp module specifically, the
    related statement applies to the initial syn packet for your secondary
    connections which will only be analyzed in the filters you use for the
    secondary connections. And once that syn packet is replied to, the
    secondary connection then becomes an established connection.

    >>>Thats why -sport 21 isnt good, it must ESTABLISHED only
    >>should be RELATED
    > I still think it should be
    > $IPTABLES -A FORWARD -i $EXTIF -o $INTIF -p TCP --sport 21 \
    > -m state --state RELATED,ESTABLISHED -j ACCEPT
    > ESTABLISHED I need for the ftp control traffic on port 21
    > RELATED I need for the ftp data traffic either to/from port 20 or a high
    > port number this should cover active and passive ftp.
    > Bye,
    > Peter

  • Next message: GuitarMan: "Re: Duane Arnold to star in "Chimpie in the mist""

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