lkml.org 
[lkml]   [1997]   [Jul]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: tcpdump & bad tcp checksum
From
Date
>>>>> "Eric" == Eric Schenk <Eric.Schenk@dna.lth.se> writes:

Eric> Jes Degn Soerensen <jds@kom.auc.dk> writes:
Eric> tcpdump only grabs the first few bytes of a packet (by default).
>> Ehhhmmm, tcpdump for Linux tend to grab the full packet rather
>> than just the header, just checked libpcap-0.4a1 and its still like
>> that. Yup this is bad, especially for `large' MTU networks such as
>> FDDI, and I guess we should do something about this at some point.

Eric> That's rather stupid. There is no need to read the full packet
Eric> in, even off a SOCK_PACKET socket. This will really bite us once
Eric> we get HIPPI support in (64k MTU anyone?).

Yup I am well aware of that, however there is no such thing as HIPPI
promiscous mode ;) So unless you get one of those switches which can
be configured to copy all packets to a seperate port you wont be able
to run tcpdump on it, but ok of course we want to support that as well.

Eric> Can someone with a
Eric> few spare hours see about getting this fixed and rolled into the
Eric> mainline sources? I'd add it to my list, but I'm snowed under
Eric> already, and I'm getting ready to move back to Canada at the
Eric> moment, so my spare time is severly limited right now.

I tried to do that but ran into some trouble with tcpdump complaining
about corrupt packets or such and had to leave it there. Its on my
to-do list as well but I wont have time to do anything about it until
the end of september.

Jes

\
 
 \ /
  Last update: 2005-03-22 13:39    [W:0.036 / U:0.244 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site