john-users - Re: filter performances

Openwall GNU/*/Linux 3.0 - a small security-enhanced Linux distro for servers

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Date: Tue, 18 Oct 2011 02:13:22 +0400
From: Solar Designer <solar@...nwall.com>
To: john-users@...ts.openwall.com
Subject: Re: filter performances

On Mon, Oct 17, 2011 at 05:01:31AM +0400, Solar Designer wrote:
[...]
> appears to be 3025989069143040 combinations, which is roughly 45% of
> the original total.  I computed it with the attached comb.c program,
> which I had tested with smaller settings (comparing its output vs.
> actual results).

Now that I know this number, I was able to find two more instances of it
on the web, computed using different approaches:

http://mathforum.org/library/drmath/view/52277.html
http://www.passwordresearch.com/files/Password%20Pool%20Possibilities%20-%20PUBLIC.xls

Most other numbers from the tables I put at:

http://openwall.info/wiki/john/policy

are not found with Google's web search - in particular, it appears
that no research had been done on keyspace reduction with "at least 2
characters of a class" requirements.  This is a bit surprising.

Alexander