Subject: [Gen-art] Gen art LC+TC review of: draft-krawczyk-hkdf-01

From: Avshalom Houri <[email-masked]>
Date: Tue, 2 Mar 2010 21:53:09 +0200

I have been selected as the General Area Review Team (Gen-ART) 
reviewer for this draft (for background on Gen-ART, please see 
http://www.alvestrand.no/ietf/gen/art/gen-art-FAQ.html). 
Please wait for direction from your document shepherd 
or AD before posting a new version of the draft. 

Document: draft-krawczyk-hkdf-01
Reviewer: Avshalom Houri
Review Date:  2010-03-02
IESG last call date: 2010-03-02 ?
IESG telechat date: 2010-03-04

Summary: The document is ready for publication as an information RFC (see 
editorial). The document is a a reasonable contribution to the area of 
Internet engineering which is covers.

Major issues:  None

Minor issues:  None

Nits/editorial comments: 

Section 2.2 Step1 :Extract

It is not easy to understand the way that the functions are defined.
For example what is the relationship between:

   PRK = HKDF-Extract(salt, IKM)
and 
   PRK = HMAC-Hash(salt, IKM)

Why Hash is an option?

Thanks
--Avshalom

---

From: Avshalom Houri <[email-masked]>
Date: Tue, 2 Mar 2010 23:18:46 +0200

Anything that will clarify this to someone not versed in the field will 
help.

Thanks
--Avshalom

From:   Hugo Krawczyk <[email-masked]>
To:     Avshalom Houri/Haifa/IBM@IBMIL
Cc:     [email-masked], General Area Review Team 
<[email-masked]>, Russ Housley <[email-masked]>, Tim Polk 
<[email-masked]>
Date:   02/03/2010 11:04 PM
Subject:        Re: Gen art LC+TC review of: draft-krawczyk-hkdf-01
Sent by:        [email-masked]

I have no problem removing the lines

PRK = HKDF-Extract(salt, IKM) 
and 
 OKM = HKDF-Expand(PRK, info, L)

which are intended as logical functions rather than an actual 
specification.

As for the parameter "Hash", this value (which describes a hash function, 
e.g. SHA-256) must be given since HMAC is not defined without it.
Since this parameter is mandatory, maybe it should not be listed under 
"Options".

In any case,  Pasi is better qualified than me to decide on these 
presentational issues.

Hugo

On Tue, Mar 2, 2010 at 2:53 PM, Avshalom Houri <[email-masked]> 
wrote:

Major issues:  None 

Minor issues:  None 

Nits/editorial comments: 

Why Hash is an option? 

Thanks
--Avshalom

---

From: Hugo Krawczyk <[email-masked]>
Date: Tue, 2 Mar 2010 16:03:14 -0500

which are intended as logical functions rather than an actual specification.

Hugo