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Date: Sun, 11 May 2014 11:10:57 +0200
From: magnum <john.magnum@...hmail.com>
To: john-dev@...ts.openwall.com
Subject: Re: Bad formats, and some ideas on helping in this area

On 2014-05-11 01:27, magnum wrote:
> On 2014-05-11 01:09, magnum wrote:
>> On 2014-05-09 19:54, jfoug wrote:
>>> I would think it easier for a user to add some format
>>> labels to a list in a conf file, than to try to muck with moving
>>> files, or
>>> possibly having to edit other files.
>>
>> This should be trivial. I can think of a way of doing it that should be
>> a one line patch in john.c. I'll try that and see if it flies.
>
> It could have been trivial. I did this:
>
>   static void john_register_one(struct fmt_main *format)
>   {
> +   if (cfg_get_bool("Disabled", "Formats", format->params.label, 0))
> +       return;
> +
>
> ...and added this to john.local.conf:
>
> [Disabled:Formats]
> rar = Y
>
>
> There is just one problem: john_register_all() is called before
> cfg_init(). The devil is, like always, in the details.

I now have a patch committed (to the autoconf topic branch for now) that 
seems to do the trick. The patch still isn't very intrusive and it's 
actually better than the above: A disabled format is never enumerated 
for automatic selections (including ambigous format warnings) but can 
still be selected explicitly. Now that it ended up like that, I consider 
this an important feature :-)

This would disable the LM format:

[Disabled:Formats]
LM = Y

You can temporarily re-enable it without deleting the entry, by setting 
the boolean to false (or N). I know where you're coming from, this will 
be VERY handy when doing "annual Big Endian testing" and the like.

magnum

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