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Re: IP-cksum incorrect in IPv4-response.

onsdag den 23 februari 2011 klockan 22:03 skrev Timo Juhani Lindfors detta:
> Mats Erik Andersson <mats.andersson@gisladisker.se> writes:
> > using packet dumps like "tcpdump -pnvXi bge0 ip" I have been
> > able to conclusively detect that kFreeBSD is inserting 0x0000
> > as the IP header checksum in any TCP response triggered by an
> Are you using tcpdump to look at the checksums of outgoing packets?
> That's not going to work with checksum offloading.
> Can you run tcpdump on the receiver side instead?

Brilliant! I was confused that on GNU/Linux the rtl8169 and e1000
drivers did not hinder the capture of headers with checksum properly
filled in, but on GNU/kFreeBSD the driver bge for Tigon really does
offload the computation. Thus I now know that the AH+ESP-transport
is receiving and transmitting impeccably correct packages. All is well.

Thanks for the illuminating reminder!


(Subscriber to debian-bsd, debian-ipv6, debian-mentors, etcetera.)

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