kernel module acquiring virtual ip's

["Sachin Shelar" <sachin.s@s7solutions.com>]

Hi,

   I have a kernel module which "acquires" virtual ips ( not assigned to  
anyone in n/w )
and then respond to any future packets coming to this virtual ip.
   I am handling ARP, TCP, UDP protocols in my module.
To get the arp stuff working I handle all the ARP requests for virtual IP  
and reply to
them with my local hardware address. I can now receive all the packets  
destined to virtual IP.
   E.g Local IP is 192.168.1.2
       Virtual ip is 192.168.1.244 ( Not existing in network )

       I catch every arp request for .244 and reply with my mac. I can now
recive all IP packets ( handled in my netfilter hooks ) destined for .244.
According to the natting rules in my module I nat the packets for .244 and  
redirect them to
some listening port on 192.168.1.2
Also I handle all the outgoing packet from 192.168.1.2 and replace the  
source to 192.168.1.244
So that the client machine recives reply from virual IP, as expected.

        192.168.1.21[32774] -> 192.168.1.244[123]

                         Nat Destination   192.168.1.21[32774] ->  
192.168.1.2[23]

(Reply) 192.168.1.2[23] -> 192.168.1.21[32774]
                         Nat Source        192.168.1.244[123] ->  
192.168.1.21[32774].



   Module works perfectly and I can establish any tcp connection ( E.g  
telnet ) with a non exitsing
IP ( 192.168.1.244) from any machine in the network.

   Problem is :-
   I want the same behaviour from the module if I try to connect from the  
same machine (local machine )
to the virtual IP.

    E.g 192.168.1.2[32772] -> 192.168.1.244[123]

                        Nat Destination   192.168.1.2[32772] ->  
192.168.1.2[23]

***** But somehow this packet after natting is dropped be the kernel and  
never reaches 192.168.1.2[23]
      Is this because the source and destination ip of this packet is same  
?????

    Hoping to get good reponse for this loooong mail :)

Thanks,
Sachin

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