On Wednesday 2009-03-25 20:56, Kristian Evensen wrote: > Jan Engelhardt skrev: >> On Wednesday 2009-03-25 20:47, Kristian Evensen wrote: >> >>> However, I have noticed a similar problem when using my module on incoming >>> packets in PREROUTING (on the multihomed receiver), the IP adress is changed >>> (accoring to my dmesg-output) but then they are not heard from again. >>> >> >> Probably dropped due to L3 or L4 checksum mismatches. While we try to >> change the checksum, I have not verified it for all cases. >> >> > Hm, I am noe sure. I recalculate the checksum (using csum_replace4 for l3 and > inet....replace4 for l4) after modifying the destination IP, and when used with > OUTPUT the checksum is correct. Since tcpdump/Wireshark outputs the packets > before they are modified I haven't been able to verify this though. You can use hexdump in the xtables module, or any other form, to dump the checksum. -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
