X.509 support in ssh (revisited)

[Ed Phillips]

On Wed, 23 Jan 2002 mouring at etoh.eviladmin.org wrote:

> Date: Wed, 23 Jan 2002 12:07:28 -0600 (CST)
> From: mouring at etoh.eviladmin.org
> To: Ed Phillips <ed at UDel.Edu>
> Cc: openssh-unix-dev at mindrot.org, secureshell at securityfocus.com
> Subject: Re: X.509 support in ssh (revisited)
>
>
>
> On Wed, 23 Jan 2002, Ed Phillips wrote:
>
> > On Wed, 23 Jan 2002, Markus Friedl wrote:
> >
> > > Date: Wed, 23 Jan 2002 17:42:46 +0100
> > > From: Markus Friedl <markus at openbsd.org>
> > > To: mouring at etoh.eviladmin.org
> > > Cc: Donald van de Weyer <donald at demag.rwth-aachen.de>,
> > >      Thanos Siaperas <thanus at ccf.auth.gr>, openssh-unix-dev at mindrot.org,
> > >      secureshell at securityfocus.com
> > > Subject: Re: X.509 support in ssh (revisited)
> > >
> > > On Wed, Jan 23, 2002 at 10:31:38AM -0600, mouring at etoh.eviladmin.org wrote:
> > > > Does X.509 really make sense with SSH?  I mean you are still not going to
> > > > get Verisigned licenses and even that you are putting your trust in a 3rd
> > > > party certificate which has no real bearing on the trust of the machine in
> > > > question.
> > >
> > > well it could make hostkey management simpler, but i see
> > > no difference between people clicking on
> > > 	"continue, i don't care about this hostkey"
> >
> > Okay... maybe someone has upgrade OpenSSH on the system and generated a
> > new hostkey.  How can you tell?
> >
> > > and
> > > 	"continue, i don't care about the certificate for this hostkey"
> >
> > The kicker is that if you manage the systems, you shouldn't see this
> > message because the client will know which CA(s) your client should trust
> > in on certs for sshd servers you want to connect to.  If you see this
> > message when certs are in play, then something is likely wrong.
> >
> > I would think that the benefit here is that if your client is configured
> > to trust only certain signers, then Joe Hacker can't play
> > man-in-the-middle during the "should I accept this hostkey" question,
> > because Joe Hacker shouldn't have the private key for the CA you trust.
> >
> > Isn't that an improvement?
> >
>
> Until your CA's employees do something brain dead like hand out a copy of
> your key to someone who 'claims' to be an employee of your company.

I wasn't the one talking about a CA "service" like Thawte or Verisign - I
was talking about a home-brew CA used just to sign OpenSSH hostkeys and
verify them so that it can all be automated.  I only need to protect the
home-brew-CA private key.  That is workable in my environment, and the
reward seems worth the effort.  Anyone else think it would be worth it?

> Refer to Micorosft and Versign issue last year which caused MS to resign a
> ton of packages and revoke a very heavily used key.

If you trust them, then you're in for a world of hurt in these situations.

> Think warm fuzzy thoughts that your CA is trustworthy. =)

Yes... it's nice isn't it? ;-P

	Ed

Ed Phillips <ed at udel.edu> University of Delaware (302) 831-6082
Systems Programmer III, Network and Systems Services
finger -l ed at polycut.nss.udel.edu for PGP public key