Subject: RE: KISS for PKIX. (Was: RE: ASN.1 vs XML (used to be RE: I-D A CTION :draft-ietf-pkix-scvp- 00.txt))

From: "Waters, Stephen" <[email-masked]>
Date: Mon, 19 Jul 1999 17:32:53 +0100

That sounds hopeful. I have no experience of the self-defense mechanisms
available with Smartcards, but something like the self-block you mention
sounds the like the job.  I guess for VPN clients that generate/store
private keys on disk with password/pin protection (encrypted), things are
slightly more exposed.  The file could be worked on independently of the
client code.  The VPN client should support some sort of key crippling if it
gets the wrong answer too many times I guess, but Smartcards would be
better.

I think I'd be happy with self-crippling Smartcards. If I didn't have that,
I'd require secondary authentication to provide the VPN server with a chance
at spotting a break-in attempt.

This concern opens up an issue with SOHO VPN devices I feel. If I have a
SOHO router loaded with a certificate used to connect a LAN-LAN VPN tunnel,
and my home is burgled while I'm on holiday, the thief has all he needs to
break in. It would be a pain to have to access a console in order to unlock
the private key each time I powered up the router, but that seems to be a
possible security policy requirement.  I guess I wouldn't mind pressing my
thumb on a Smartcard each morning until 'the green light came on'.  

Thanks, Steve.

-----Original Message-----
From: Anders Rundgren [mailto:[email-masked]]
Sent: Monday, July 19, 1999 2:59 PM
To: Stephen Kent; 'Waters, Stephen'; [email-masked]'
Subject: RE: KISS for PKIX. (Was: RE: ASN.1 vs XML (used to be RE: I-D
ACTION :draft-ietf-pkix-scvp- 00.txt))

Stephen W,
<snip>
>As an example, I am using a certificate Smartcard with a pin-number
>protected private key for VPN access to my head office.  If the laptop and
>smartcard are stolen, the thief can play with them until he has cracked the
>pin number. The thief can do this off-line with no contact with the VPN
>server. Once cracked, they can connect to the Internet, and contact the VPN
>server.

Is it that easy?
I doubt that a thief can "play" with the smart-card until he/she cracks the
PIN-code.

After lets say tree tries most smart-cards become  "neutralized" and
requires a
much harder PUK-code to be reactivated.  It is also easy for a smart-card
to introduce a for a human negligible delay that makes computerized attacks
less fruitful.

The only method I know of requires opening the chip and manipulations at
silicon-
level.  This is not for everybody.

Anders