The Answer Guy 39: Another "No Login" Problem: A little tip
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Another "No Login" Problem: A little tip
From Jens Christian Gram on Wed, 03 Mar 1999
I have experienced the "no login" problem in both RH 5.1 and RH 5.2.
The problem seems to be that the /bin/passwd command has applies some
restrictions to the entered passwords (they can not be to short, to
simple ...). When you use the graphic tool, no restrictions are applied,
but you can not log in, if the password violates the restrictions from
passwd.
I hope you understand what I mean, and that you can use my help, even
though I am relatively new at linux.
Jens Christian Gram
Of course! That explains it.
The normal Linux 'passwd' command does attempt to enforce a
"strong passwords" policy --- to ensure that the user will
pick passwords that are unlikely to be in a potential
attacker's 'crack' dictionary. 'crack' is a program that
hashes (encodes) a list of words (a dictionary) into every
variant of the way it might appear in a given password
file (/etc/passwd). This is much more efficient than a
true "brute force" attack.
In any event --- the GUI tool obviously has a bug it
it --- since it just calls the underlying 'passwd'
command and doesn't relay the error messages back to
the user. I personally consider that to be a major
flaw and would suggest that sysadmins remove this
program (python script?) from their systems until it's
fixed.
Copyright © 1999, James T. Dennis
Published in The Linux Gazette Issue 39 April 1999