[lwip-devel] RE: [bug #22120] Problem in icmp_dest_unreach

[Bill Auerbach]

> Follow-up Comment #1, bug #22120 (project lwip):
> 
> I'm not sure your problem is on lwIP. I did this test on September CVS
> HEAD
> and on 1.3.0-RC1 without any problems with Wireshark 0.99.7 :
> 
> I send with iperf udp packets to my lwIP target on a unbinded port, lwIP
> reply with a ICMP "Destination unreachable", and in my wiresshark capture,
> I
> don't see any checksums errors on :
> 
> - IP header checksum [correct]
> - ICMP checksum [correct]
> - on IP and UDP payload (wireshark doesn't mark them as "incorrect")
> 
> I will suppose you know that old wireshark releases (0.99.5 by example)
> was
> bugged on UDP checksums (mainly on fragmented datagrams from memory), and
> that
> your pc network interface doesn't perform any checksum offload processing
> (with give some checksums errors, but last wireskark releases mark them
> like a
> warning).

The only error is in the UDP length.

> Can you tell me what is your wireshark release, and perhaps attach the
> capture file?

0.99.6a - the packet in question is attached.  I changed the length to 8
from the hint in WireShark.

Bill

icmp_type_3.pcap
Description: Binary data