Re: Preparing to Write Dissector for New IPv6 Destination Option

[Nalini Elkins <nalini.elkins () insidethestack com>]

Thanks so much!

I will double check:

"page 8 says for the Options Length field "This field MUST be set to 16.” But really the field must be set to 12, since 
that’s the length of the PDM option."

When I try to execute the LUA using the "Evaluate" option of Wireshark GUI, I get:
Lua: Error During execution of dialog callback:

 [string "-- A simple dissector script for draft-ietf-i..."]:63: Field_new: A Field extractor must be defined before 
Taps or Dissectors get called

Is there another way I should be doing this? 
Thanks,


Nalini Elkins
Inside Products, Inc.
(831) 659-8360
www.insidethestack.com



________________________________
From: Hadriel Kaplan <hadrielk () yahoo com>
To: Nalini Elkins <nalini.elkins () insidethestack com> 
Cc: Developer support list for Wireshark <wireshark-dev () wireshark org> 
Sent: Monday, July 6, 2015 10:32 AM
Subject: Re: [Wireshark-dev] Preparing to Write Dissector for New IPv6 Destination Option


Try the attached.

There is one caveat: it won’t work correctly if you have a IPv6 Destination Options Header with the PDM option but also 
other option types in that same header.

Also, I have no idea if I did the time scaling correctly.

BTW, there’s a bug in the draft: page 8 says for the Options Length field "This field MUST be set to 16.” But really 
the field must be set to 12, since that’s the length of the PDM option.




-hadriel




> > On Jul 6, 2015, at 9:15 AM, Nalini Elkins <nalini.elkins () insidethestack com> wrote:
> >
> > Hello All,
> >
> > Please let me know if I should post this to the user's list.
> >
> > My proposal for a new IPv6 Destination Option was recently adopted by the IP Performance Metrics Working Group of 
> > the IETF.  It is at: 
> > http://datatracker.ietf.org/doc/draft-ietf-ippm-6man-pdm-option/   
> >
> > I have started implementation of this on FreeBSD.  Of course, one of the steps in this process is to write a 
> > Wireshark dissector!
> >
> > I have started with an LUA implementation.  (See attached)  I am having some problems as this is my first time with 
> > LUA.  
> >
> > The first problem is that I do not seem to be pointing to the payload of the IPv6 Destination Option correctly.  
> > The parsing should be for the field ipv6.opt.experimental.  But, I am not able to make this work.  I would 
> > appreciate any help.
> >
> > A PCAP is also attached.
> > Thanks,
> >
> > Nalini Elkins
> > Inside Products, Inc.
> > (831) 659-8360
> > www.insidethestack.com
> > <pdmIPSec.pcapng><pdmOriginal.lua>___________________________________________________________________________
>
>
>
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