Problem with packt transmission

[vijaykumar v <vij@xxxxxxxxxxxxx>]

Hi,
  I implemented a virtual network interface which uses the ethernet 
card to transmit and recieve packets.

I installed this module on two hosts A and B. Here is what happens when 
I send a (ping)packet from one host to another -
   a. The packet is transmitted from A
   b. The packet is recieved at B
   c. A ping response gets generated in host B.
       The ethereal on machine B shows ping reply being *transmitted*.
       I verified all the fields of the packet - everything inluding
       the checksum is perfect.
   d. Host A recieves no such packet.

To the interface, request and reply are two equivalent packets. I dont 
know why replys dont get sent. Recieving multiple packets is also fine. 
I tried to put broadcast mac address on all frames - even then the same 
situation repeats. This behaviour happens 10 out of 10 times.

The problem is not only with ping. Its with all type of pkts - responses 
dont come out of the ethernet card. eg., when I send a SYN, ethereal 
shows a SYN/ACK being sent, but is not actually transmited.

What can be the chances/reason of a packet not getting transmitted after 
ethereal showing that the packet is transmitted. ifconfig on the machine 
shows zero packets dropped from the eth0 interface.

Any help will be great.

ciao,
Vij

--
*****************************************************************
        V.Vijayakumar   http://www.it.iitb.ac.in/~vij/

  "Anything less than a conscious commitment to the important
       is an unconscious commitment to the unimportant."
*****************************************************************



--
Kernelnewbies: Help each other learn about the Linux kernel.
Archive:       http://mail.nl.linux.org/kernelnewbies/
FAQ:           http://kernelnewbies.org/faq/