Messages in this thread | | | Date | Tue, 18 Apr 2006 15:44:58 +0530 | Subject | kernel module acquiring virtual ip's | From | "Sachin Shelar" <> |
| |
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
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |