TCP checksum

[Amit Mondal]

Hi,

Could anyone pls tell me the function freebsd provides for calculating TCP
checksum.

What I am doing, I am sniffing packet using divert packet and changing the
destination address of the packet. Now, since TCP checksum calculation
include Pseudo head (src dest IP ....) I need to recalculate TCP checksum.
Is there any way to recalculate the checksum incrementally.

Thanks in advance.

Rgds
-Amit