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Wireshark-dev: Re: [Wireshark-dev] Extracting a GUID as a string from a TVB, SMB2 Extra Create

From: Richard Sharpe <realrichardsharpe@xxxxxxxxx>
Date: Sat, 4 Oct 2014 14:27:43 -0700
On Sat, Oct 4, 2014 at 2:23 PM, Pascal Quantin <pascal.quantin@xxxxxxxxx> wrote:
> 2014-10-04 23:17 GMT+02:00 Richard Sharpe <realrichardsharpe@xxxxxxxxx>:
>>
>> Hi folks,
>>
>> I have come across a case where an Extra Create Parameter's TAG for a
>> CREATE request is a GUID. This is like things like DH2C (Durable
>> Handles V2) but it is for SHVXD, the crazy VHD over SMB2 stuff.
>>
>> The tag is a GUID.
>>
>> In dissect_smb2_olb_string, or something like it, I want to extract
>> the GUID as a string, eg "9ECFCB9C-04C1-980E-..." and use that to look
>> up the dissection routines ... [1]
>>
>> How do I extract such as a string?
>>
>> [1] Curiously there seems to be an example of such already in the form
>> of APP_INSTANCE stuff, but it seems like the tag is encoded in that
>> case in the string form of a GUID. In the SHVX case, it is a binary
>> GUID. Sigh.
>
>
> Hi Richard,
>
> presumably you want to fetch the GUID from the TVB thanks to the
> tvb_get_ntohguid() / tvb_get_letohguid() / tvb_get_guid() routines and then
> convert it to a string thanks to guid_to_ep_str() function.

OK, that looks like it will do it.

-- 
Regards,
Richard Sharpe
(何以解憂?唯有杜康。--曹操)