Re: key usage - key encipherment or data encipherment

[Sam Roberts <sroberts@xxxxxxxxxxxx>]

Wrote Simon McMahon <Simon_McMahon@xxxxxxxxxxxxxxxxx>, on Fri, May 20, 2005 at 07:50:03AM +1000:
> The example should match typical usage and doesn't have to cover every
> possibility.

It probably isn't "typical", but the TCG uses RSA private keys encrypted
with RSA public keys of the same strength.

IIRC, instead of encrypting d,p-1,q-1,... (which would be too large),
they only encrypt p. The decryptor can recreate the rest of the private
key from the public key and knowledge of p.

Cheers,
Sam


> 
> Simon.
> 
> 
> Simon McMahon
> 
> Work: (07) 31311420
> Mobile: (043) 2294180
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> 
> >>> <diegofv@xxxxxxxxxxx> 05/18/05 12:15am >>>
> But, if the asymmetric private key is based on elliptic curves?
> 
> Diego
> 
> ----- Mensaje Original -----
> Remitente: "Simon McMahon" Simon_McMahon@xxxxxxxxxxxxxxxxx 
> Destinatario: housley@xxxxxxxxxxxx, ietf-pkix@xxxxxxxx 
> Fecha: Martes, Mayo 17, 2005  1:03am
> Asunto: Re: key usage - key encipherment or data encipherment
> 
> >
> >The example for 'keyEncipherment' should not include an "RSA public 
> >key encrypting an asymmetric private key", which, if it is also RSA 
> >is too big to encrypt with the public key. Surely, an RFC shouldn't 
> >list impossible cases as examples.
> >
> >Simon.
> >
> 
> 
> 
> 
> 
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