Re: Which password cipher ?

[Julio Merino <jmmv84%gmail.com@localhost>]

On 12/1/10 11:49 AM, Steven Bellovin wrote:
> On Dec 1, 2010, at 6:14 05AM, Julio Merino wrote:
>
> > On 12/1/10 10:59 AM, Robert Elz wrote:
> > >      Date:        Wed, 1 Dec 2010 09:42:17 +0000
> > >      From:        Julio Merino<jmmv%NetBSD.org@localhost>
> > >      
> > > Message-ID:<AANLkTimY1WcUrXgdObPZzi_jv2ysKV+9esJ46s5CXn=e%mail.gmail.com@localhost>
> > >
> > >    | Which makes me wonder... why do we even *ask* people to choose a
> > >    | cypher algorithm during install?  Couldn't we, as the developers of
> > >    | the system, make a good choice for our users (and let them change it
> > >    | after installation if they so wish, just as they can with everything
> > >    | else)?  (It just feels stupid that we have a question in sysinst for
> > >    | something as trivial as this but we don't have a way to select, e.g.
> > >    | which services to enable.)
> > >
> > > It is (of course) because we really want sysinst to encourage setting a
> > > root password, and we need to know which cipher to use to set that one with,
> > > before it is set.   Nothing sysinst does inhibits in any way enabling
> > > the various services, but setting a root password with the "wrong" cipher
> > > would be annoying.
> > "Of course".  But really, who cares?  Why would you ever have to think about 
> > what cypher algorithm to use, *specially* during installation?  And if you want to change 
> > it at all after install, you should know how to and, therefore, you should know what 
> > implications that has and how to deal with them.
> The simple answer is password file compatibility -- other systems accept the older 
> formats.  Over the years, I've seen many instances where someone will say "send me 
> your passwd file line".  DES is the most compatible; the Blowfish and md5 methods 
> are used by other open source systems; the HMAC-SHA1 scheme was developed for NetBSD and 
> doesn't exist elsewhere unless they've picked up our code.
I understand that having the ability to change the cypher algorithm can 
be handy (I'm not arguing otherwise).  But that doesn't mean such a 
tunable needs to be available during the installation procedure.

Anyway, thanks for the explanation.