Prob with hook reg in iptables
varun at rocsys.com
Thu Jun 1 08:02:54 CEST 2006
I have a setup where iam using iptables. I have squid
running on my statem. Now the scenario is that this sytem is my router.
I have eth0 connected to LAN, eth1 to Wan 1 and eth2 to Wan2. In the
same box i also have a propratery FW which has Load Balancing feature.
Now my intention is i start iptables first so that it registers with
netfilter hook first.
So policy is like this
iptables -t nat -D PREROUTING -i eth0 -p tcp -j REDIRECT --to-port
In the port 8080 i have squid running.
As far as filtering of iptables is concerned it is allow all.
So my basic FW functionality is concerned it is taken care by My
Propratery FW. It will do the natting for both wan interfaces in Load
Now what i expect is that iptables will get all the packets first and
then packet will go to my firewall and might get dropped if ACL matches
else it is success. Once success i expect the packet to be redirected to
port 8080 where squid can take control.
Now my problem is that even though iptables is registered first when i
log the packets using iptables for the above rule i find that no packets
are comming to iptables there by no packets are going to proxy. I get
only some multicast packets.
From lan iam able to browse well and all my traffic is going tru my FW
rather that first through iptables. Why?
As far as my knowledge first registered module get the packet first and
if the action is NF_ACCEPT the the next registered module to the hook
gets it right? If yes why is it not happening? Another thing is what
exactly does redirect do does it mangel the packet?
Please help me in this?
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