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Date: Fri, 26 Aug 2016 13:45:44 -0500
From: jfoug <jfoug@...nwall.net>
To: john-dev@...ts.openwall.com
Subject: Re: Re: GPU-side mask mode

On 8/26/2016 1:28 PM, magnum wrote:
>
>> Is there a way to make this into a module (like we have done with SIMD
>> code), so that it does not have to be hooked so deeply into the format's
>> kernel code?  There would still be some interface code (like we have
>> with SIMD), but the main functionality is external.
>
> Yes but it's currently an enormeous amount of code all over the 
> CPU-side format. It needs a LOT of work. Ideally we should just call 
> some shared function from reset(), and some other function from 
> crypt_all() (and so on) and be done with it.
>
> On kernel side, things are much better. It's the host code that knocks 
> me cold.

It's good that the 'kernel' side is 'cleaner' and somewhat modular.   I 
agree with you on the location of the CPU hooking code.  So if the code 
could be made more 'generic' (with no loss of speed), then simply 
changing a few lines in those 2 CPU-side format functions and adding 
whatever kernel hooks are needed, and any format would get the benefits 
of GPU masking.  That was my questions.   It would be a HELL of a lot 
easier to do this now, than to hammer out a dozen more format, and then 
have to decouple all of those.  Just think of having to decouple 50 
formats that have SIMD code intertwined (like some of the -ng formats). 
It would really slow down enhancements or usage of the SIMD stuff.  Yes, 
the SIMD callable code is not 100% the fastest always, but it is pretty 
darn close, AND is pretty trivial to simply hook it into a format.

>
>> I am sending this offlist, as I do not want to pollute your thread IF
>> this is total PEBCAK
>
> No you didn't :-)  But this is a good discussion here.

I saw that the moment I clicked send, that I had not changed the 'to:' 
value, lol.  Oh well, I would have brought it to list anyway, once I saw 
it was not 100% PEBCAK.

Jim.

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