Wireshark-bugs: [Wireshark-bugs] [Bug 10692] New: Multipath TCP: checksum displayed when it's no
Date Index · Thread Index · Other Months · All Mailing Lists
Date Prev · Date Next · Thread Prev · Thread Next
From: bugzilla-daemon@xxxxxxxxxxxxx
Date: Tue, 11 Nov 2014 16:26:41 +0000
Bug ID 10692
Summary Multipath TCP: checksum displayed when it's not there
Product Wireshark
Version 1.12.0
Hardware All
OS All
Status UNCONFIRMED
Severity Trivial
Priority Low
Component Dissection engine (libwireshark)
Assignee bugzilla-admin@wireshark.org
Reporter frederik.vanderstraeten+wireshark@gmail.com 

Created attachment 13255 [details]
Capture file that shows the problem

Build Information:
Version 1.12.0 (Git Rev Unknown from unknown)

Copyright 1998-2014 Gerald Combs <gerald@wireshark.org> and contributors.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Compiled (64-bit) with GTK+ 3.12.2, with Cairo 1.13.1, with Pango 1.36.3, with
GLib 2.41.1, with libpcap, with libz 1.2.8, with POSIX capabilities (Linux),
with libnl 3, with SMI 0.4.8, with c-ares 1.10.0, with Lua 5.2, without Python,
with GnuTLS 3.2.16, with Gcrypt 1.5.3, with MIT Kerberos, with GeoIP, with
PortAudio V19-devel (built Feb 25 2014 21:09:53), without AirPcap.

Running on Linux 3.16.0-24-generic, with locale en_US.UTF-8, with libpcap
version 1.6.2, with libz 1.2.8, GnuTLS 3.2.16, Gcrypt 1.5.4.
       Intel(R) Core(TM) i7-3537U CPU @ 2.00GHz

Built using gcc 4.9.1.

Wireshark is Open Source Software released under the GNU General Public
License.

Check the man page and http://www.wireshark.org for more information.
--
Multipath TCP has an optional checksum, part of its "Data Sequence Signal" TCP
option. The RFC (6824) says that the presence or non-presence of this checksum
should be inferred from the option length (and only if the M flag is set).
However, Wireshark just assumes it is there if the M flag is set, and shows the
start of the data following the TCP option as if it was this checksum.

I have attached a capture file that shows the problem. When you click
"Multipath TCP Checksum" in the first frame, you will see that Wireshark
highlights the letters t and e that are actually part of the data, and shows
them as if they were the checksum.

You are receiving this mail because:
  • You are watching all bug changes.