Re: Lua in-kernel (lbuf library)

[Lourival Vieira Neto <lourival.neto%gmail.com@localhost>]

On Tue, Oct 15, 2013 at 7:22 PM, Alexander Nasonov <alnsn%yandex.ru@localhost> 
wrote:
> Lourival Vieira Neto wrote:
>> I'm developing a library to handle buffers in Lua, named lbuf. It is
>> been developed as part of my efforts to perform experimentation in
>> kernel network stack using Lua. Initially, I intended to bind mbuf to
>> allow, for example, to write protocols dissectors in Lua. For example,
>> calling a Lua function to inspect network packets:
>>
>> function filter(packet)
>>   if packet.field == value then return DROP end
>>   return PASS
>> end
>>
>> Thus, I started to design a Lua binding to mbuf inspired by '#pragma
>> pack' and bitfields of C lang. Then, I realized that this Lua library
>> could be useful to other kernel (and user-space) areas, such as device
>> drivers and user-level protocols. So, I started to develop this
>> binding generically as a independent library to give random access to
>> bits in a buffer. It is just in the early beginning, but I want to
>> share some thoughts.
>
> I wonder if you looked at Lua support in Wireshark [1]? Unfortunately,
> it's GPL and they even have a special section 'Beware the GPL' on wiki.
>
> [1] http://wiki.wireshark.org/Lua
>
> Alex

Yes. In fact, I have already implemented a Wireshark dissector in Lua
for a proprietary protocol that I was designing, inspired in ERP, to
detect network loops. WS Lua dissectors also served as inspiration.
However, I just used the API; I never looked at the binding
implementation.

Wireshark Lua dissectors is a good example of what can be done with
Lua in that sense. But I'm looking for a more generic API that could
allow random bit access in a buffer using Lua table notation, that
could also be used to communicate with devices, for example. I think
(IMHO) that lbuf masks is more straight forward.

Regards,
-- 
Lourival Vieira Neto