Re: MD5 password salt calculation

From: Jacques A. Vidrine (n@nectar.cc)
Date: 12/30/01 

Date: Sun, 30 Dec 2001 00:02:48 -0600
From: "Jacques A. Vidrine" <n@nectar.cc>
To: Allen Landsidel <all@biosys.net>

On Sun, Dec 30, 2001 at 12:58:08AM -0500, Allen Landsidel wrote:
> Using something like strftime(3) defeats this, depending on the format used
> in the call. If you have 256 possible salts, then an attacker may be
> dissuaded from generating the lookup.

Actually, even really isn't enough salt, and is one of the several
problems with the traditional UNIX crypt scheme.

> If you only have 24 (say strftime
> was called to generate a normal human-readable time, and the two characters
> for the hour were used) then the purpose behind the salt is entirely
> defeated, and may as well be left off just to make the code cleaner.

Yes, that would be bad. But that's not what the original poster
described.

Cheers, 

-- 
Jacques A. Vidrine <n@nectar.cc>                 http://www.nectar.cc/
NTT/Verio SME          .     FreeBSD UNIX     .       Heimdal Kerberos
jvidrine@verio.net     .  nectar@FreeBSD.org  .          nectar@kth.se
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