Wireshark-dev: Re: [Wireshark-dev] Preparing to Write Dissector for New IPv6 Destination Option
From: Hadriel Kaplan <[email protected]>
Date: Mon, 6 Jul 2015 13:56:09 -0400
You probably need a more recent version of Wireshark. That looks like a bug that was fixed last year.
You should be running Wireshark 1.12.x (the current released version).

Also, don’t try loading Lua scripts from the Evaluate window - that frequently doesn’t work and isn’t supported - instead, Lua scripts should only be loaded by either being in the Personal Plugins directory, or from the command line.  To find your Personal Plugins directory, in Wireshark go to Help->About Wireshark, and select the “Folders” tab. The “Personal Plugin” directory/folder should be listed there. Just copy the ‘pdm.lua’ file to that directory and restart Wireshark.

Or if you can start wireshark from the command line, then you can use the “-X lua_script:<scriptname>” option to load the script.
 So like “wireshark -X lua_script:pdm.lua” if you’re in the same directory as ‘pdm.lua’ file is (or put in the full path if not).

-hadriel


> On Jul 6, 2015, at 1:42 PM, Nalini Elkins <[email protected]> wrote:
> 
> 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 <[email protected]>
> To: Nalini Elkins <[email protected]> 
> Cc: Developer support list for Wireshark <[email protected]> 
> 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 <[email protected]> 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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