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From: Budai Laszlo <lbudai@ms.sapientia.ro>
To: netfilter@lists.netfilter.org
Subject: ip_conntrack_ftp problem
Date: Fri, 28 Mar 2003 09:40:40 +0200	[thread overview]
Message-ID: <3E83FC78.7080801@ms.sapientia.ro> (raw)



we use Redhat Linux 8 to connect our lan to the internet. Internally we 
are using private addresses which are SNAT-ed (MASQUERADE) by the linux box.

We set up a firewall which in the forward chain looks like:

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination
ACCEPT     all  --  anywhere             anywhere           state RELATED
ACCEPT     tcp  --  192.168.101.25       anywhere           tcp dpt:telnet
ACCEPT     tcp  --  192.168.101.24       anywhere           tcp dpt:telnet
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:ldap
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:imap
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:rtsp
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:cvspserver
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:cvspserver
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:5190
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:squid
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:https
ACCEPT     udp  --  192.168.101.0/24     anywhere           udp dpt:domain
ACCEPT     udp  --  192.168.101.0/24     anywhere           udp dpt:7070
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:7070
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:https
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:5050
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:pop3
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:http
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:domain
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:smtp
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:ssh
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:ftp
ACCEPT     tcp  --  192.168.101.0/24     anywhere           tcp dpt:ftp-data
DROP       tcp  --  192.168.101.0/24     anywhere


so we try to limit the access just to a few accepted services. We are 
loading the ip_conntrack_ftp and ip_nat_ftp modules:

# lsmod
Module                  Size  Used by    Not tainted
ipt_state               1080   1  (autoclean)
cls_u32                 6332   2  (autoclean)
sch_cbq                14912   2  (autoclean)
ip_nat_ftp              4240   0  (unused)
ip_conntrack_ftp        5088   0  (unused)
eepro100               22264   1
8139too                17736   1
mii                     2156   0  [8139too]
iptable_mangle          2776   1  (autoclean)
ipt_MASQUERADE          2200   0  (autoclean)
ipt_REDIRECT            1368   3  (autoclean)
iptable_nat            19960   2  (autoclean) [ip_nat_ftp ipt_MASQUERADE ipt_REDIRECT]
ip_conntrack           21244   3  (autoclean) [ipt_state ip_nat_ftp ip_conntrack_ftp ipt_MASQUERADE ipt_REDIRECT iptable_nat]
iptable_filter          2412   1  (autoclean)
ip_tables              15224   8  [ipt_state iptable_mangle ipt_MASQUERADE ipt_REDIRECT iptable_nat iptable_filter]
mousedev                5524   0  (unused)
keybdev                 2976   0  (unused)
hid                    22244   0  (unused)
input                   5920   0  [mousedev keybdev hid]
usb-uhci               26188   0  (unused)
usbcore                77024   1  [hid usb-uhci]
ext3                   70336   3
jbd                    52212   3  [ext3]
sym53c8xx              68240   4
sd_mod                 13552   8
scsi_mod              107176   2  [sym53c8xx sd_mod]


but ftp trough the firewall still does not work. :(
what is wrong?

Thanks,
Laszlo





             reply	other threads:[~2003-03-28  7:40 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2003-03-28  7:40 Budai Laszlo [this message]
2003-03-28  8:27 ` ip_conntrack_ftp problem Vincent Lim
2003-03-28  9:43   ` Budai Laszlo
2003-03-28 10:19     ` Vincent Lim
2003-03-28 10:43       ` Cedric Blancher
2003-03-28 10:59         ` Vincent Lim
2003-03-28 17:06           ` Cedric Blancher
2003-03-28 12:17         ` Jozsef Kadlecsik
2003-03-28 12:46           ` Cedric Blancher
2003-03-28 14:10             ` Jozsef Kadlecsik
2003-03-28  8:50 ` Michael K
  -- strict thread matches above, loose matches on Subject: below --
2003-03-28 12:44 blancher
2003-03-28 12:45 blancher

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