RE: Comments on x942-05 draft

[Russ Housley <[e-mail]>]

Burt:

You are correct.  The corrent write-up does specify the content-encryption
algorithm OID.  I agree that we should replace the content-encryption
algorithm OID with the key-wrap algorithm OID.

Russ


At 01:07 PM 3/10/99 -0800, Burt Kaliski wrote:
>Dear Russ --
>
>Thanks for the CMS excerpt.
>
>My question is about the parameters to the X9.42 KDF, specifically the OID
>associated with the derived key. The field is defined as follows:
>
>	algorithm is the ASN.1 algorithm OID of the symmetric algorithm with
>which
>	     this KEK will be used. 
>
>I'm assuming that within CMS, the OID would be id-alg-CMS3DESwrap or
>id-alg-CMSRC2wrap.
>
>x942-05 is unclear about this, as "symmetric algorithm" might be interpreted
>as the OID for RC2 or triple-DES, not the key wrapping mechanism. I think
>it's better to identify the key wrapping mechanism, in case there's more
>than one with the same underlying symmetric algorithm. One risk, of course,
>is that the OID for the key wrapping mechansim might be too generic -- so
>there should be some way to include parameters (if any) to the key wrapping
>OID as input to the KDF.
>
>-- Burt
>
>
>> ----------
>> From: 	Russ Housley[SMTP:[e-mail]]
>> Sent: 	Friday, March 05, 1999 10:05 AM
>> To: 	Burt Kaliski
>> Cc: 	Eric Rescorla; [e-mail]
>> Subject: 	RE: Comments on x942-05 draft 
>> 
>> Burt:
>> 
>> Please take a look at CMS for this answer.  The AlgorithmIdentifier used
>> to
>> name Ephemeral-Static Diffie-Hellman has a parameter, and that parameter
>> specifies the key wrap algorithm.
>> 
>> Russ
>>