in_cksum() for ip packets with multiple mbufs
kamal_ckk at yahoo.com
Sun Oct 23 01:30:19 PDT 2005
i come across this unusual problem.
i changed the ip_tos field of the struct ip and
the checksum by using in_cksum().
when the packet uses only one mbuf the computed
checksum is ok but when the packet uses more than one
mbuf then the computed checksum is wrong.
eg. pinging with payload less than 1470 bytes is ok
but with payload greater than 1480 bytes does not
work. (the error being bad checksum --that i knew
by capturing network packets by ethereal)
is it a real problem or i have made some mistake.
i put the code before the if_output() in the
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