Drop and Create a new packet

[pavankvnaidu]

I want to modify the packet data.
if the data is ‘abc’ i want to change it to ‘1234567’ how to do this?

I have tried just simply modify the packet as decribed in the post,
http://ntkernel.com/forum/viewtopic.php?t=19&highlight=modify+packet
but it doesn’t work because, the size of the modified packet is greater than the size of original packet. In this case, only the size of original data is being transmited i.e only ‘123’ is being transmited.

The alternate solution is to drop the actual packet and create the new packet with the same sequence number(SYN) and inject it into the stack.

Can any one help?

Thank you.

[ByTE]

With TCP protocol you MUST modify SN field of packet. No other way.

[pavankvnaidu]

if we change the SYN of one packet, what happens to the otherpackets that are in queue?

can you please explain it in more detail?

[ByTE]

You must change all sequence values of packets in current TCP sequence.
This in hard work (not really).

[Author]

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