Subject: Private Key Cloning

From: [email-masked]
Date: Mon, 19 Jun 2000 10:11:05 -0400

Juergen,

If a private key generated within a hardware cryptographic module is
securely wrapped within that same module, is then exported to another
similar hardware cryptographic module through an authenticated key exchange
where it is unwrapped and both of these private keys are then used to
perform electronic signatures in a load balancing situation (e.g. OCSP or
TSA server), do you mean this would not be legal in Germany?

Regards,

Francois
___________________________________
Francois Rousseau
Director of Standards and Conformance
Chrysalis-ITS
1688 Woodward Drive
Ottawa, Ontario, CANADA, K2C 3R7
[email-masked]      Tel. (613) 723-5076 ext. 419
http://www.chrysalis-its.com     Fax. (613) 723-5078

-----Original Message-----
From: Juergen Brauckmann [mailto:[email-masked]]
Sent: Monday, June 19, 2000 5:25 AM
To: [email-masked]
Subject: Re: I-D ACTION:draft-ietf-pkix-time-stamp-08.txt

At 11:24 19.06.00 +0200, Joerg Seidel wrote:
>> If a TSA has more than one key for performance purposes, I would assume
they
>> are just copies of the same private key cloned in different cryptographic
>> modules for performance and load balancing reasons.
>
>Since it is not possible with some cryptograpic modules to make copies of
the
>private key...

And sometimes not legal... .

Regards,
   Juergen

-- 
Juergen Brauckmann             Tel.:  040 / 8080 26 311
TC TrustCenter GmbH            Fax.:  040 / 8080 26 126
Sonninstraße 24-28   	    mailto:[email-masked]
20097 Hamburg 		    http://www.trustcenter.de

---

From: Paul Koning <[email-masked]>
Date: Mon, 19 Jun 2000 10:48:17 -0400 (EDT)

>>>>> "FRousseau" == FRousseau  <[email-masked]> writes:

 FRousseau> Juergen, If a private key generated within a hardware
 FRousseau> cryptographic module is securely wrapped within that same
 FRousseau> module, is then exported to another similar hardware
 FRousseau> cryptographic module through an authenticated key exchange
 FRousseau> where it is unwrapped and both of these private keys are
 FRousseau> then used to perform electronic signatures in a load
 FRousseau> balancing situation (e.g. OCSP or TSA server), do you mean
 FRousseau> this would not be legal in Germany?

How would you guarantee that there's no man in the middle?  The only
way would be to have a prior out of band secure setup of
authenticating data, such as a shared secret or public keys used for
this key exchange process.  While the user of such a device can ensure
that this is done right, the manufacturer of the devices cannot.

It doesn't surprise me at all to see devices that don't allow this.
It makes good security sense to omit such a capability.

   paul