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Date: Mon, 21 Nov 2011 18:43:51 +0100
From: Samuele Giovanni Tonon <>
Subject: Re: best way to get ciphertext

On 11/21/11 17:52, Solar Designer wrote:
> Hi Samuele,
> Thank you for bringing this topic up - I mean not just "getting the
> ciphertext", but scalability issues for fast hashes in general.


> On Mon, Nov 21, 2011 at 02:59:23PM +0100, Samuele Giovanni Tonon wrote:
>> i'm trying to add key comparison inside the opencl kernel code
>> trying to see if this add more speed to the process.
> Yes, but this is difficult to do.
>> at the moment all the job is done inside crypt_all() in which
>> i set the salt, the list of cleartext password to hash, the output
>> buffer .
>> i tried also to pass to opencl kernel ciphertext password by calling
>> "binary", however with my great disappoint i'm not getting the password
>> but some random data.
> What "ciphertext password"?  John normally has many hashes loaded at
> once, including often many per salt.  Having just one hash to crack (per
> salt, if applicable) is only a special case.

of course, having one hash per salt is a special case but it's the one
that occurs most on nsldaps (lucky me ); i still need to see the whole
flow of code during a "many hash per salt" case.

>> i tried to print inside crypt_all and cmp_all binary value with a simple:
>> printf("cry %x %x %x %x %x \n ", ((ARCH_WORD_32 *)binary)[0],
>> ((ARCH_WORD_32 *)binary)[1], ((ARCH_WORD_32 *)binary)[2], ((ARCH_WORD_32
>> *)binary)[3], ((ARCH_WORD_32 *)binary)[4]);
> No idea what binary value you're trying to print here.  There might not
> even be a symbol called "binary" and available inside crypt_all().
> Well, maybe you happen to have a function called binary(), like many
> formats do, and you print portions of its code here? ;-)

yes, that's what happened; i'm still having bad times remembering C
programming as i'm most used to objective programs; i figured later that
i was just printing beautifoul portion of the code :-)

>> however while on cmp_all i get the right "numbers", on crypt_all
>> i get nothing valuable.
>> since it looks like binary is not available inside crypt_all
>> (because not yet setted?)
> Yes, not available there.  No, for more fundamental reasons.

that's what i've learned today, i hoped it was possible, it isn't :-)

btw i did some comparison just to see how much it would have improved,
so basically i cracked looking for a hash that was like a portion of
code ( :-) ) and i was able to gain just a 3 % which is not really worth.


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