RE: Comments on draft-ietf-bfd-hmac-sha

["Bhatia, Manav (Manav)" <[e-mail]>]

Hi Nobo,

Thanks for the review. We'll be addressing them all in the next revision.

One quick comment.

It's a standard track document because vendors have to implement the crypto-mathematics given in this document down to the last dot (if there ever was such a phrase) to come up with an interoperable implementation.

The crypto-maths here includes the notion of an Additional Pad (Apad) which increases the security, and isnt defined in the regular NIST documents that we refer to in this draft. How it increases the security is a long painful discussion best done in a pub when everything around is us already fuzzy and blurred.

Cheers, Manav

> -----Original Message-----
> From: Rtg-bfd [mailto:[e-mail]] On Behalf Of Nobo Akiya
> (nobo)
> Sent: Tuesday, April 15, 2014 3:51 AM
> To: [e-mail]
> Cc: [e-mail]
> Subject: Comments on draft-ietf-bfd-hmac-sha
> 
> Hi Authors,
> 
> I have reviewed your draft (draft-ietf-bfd-hmac-sha), comments below.
> Since document is nearing expiration, perhaps you can address some of
> these comments and re-publish?
> 
> 
> (1) Section 3, couple of places
> 
> s/avaliable/available/g
> 
> 
> (2) Section 2, 3, 4
> 
> I see that most texts from sections 3 & 4 overlaps with texts in draft-
> ietf-bfd-generic-crypto-auth. Are texts in section 2 something required
> for BFD to use HMAC-SHA (i.e. required to interop)?  I'm just wondering
> why this is a standard-track document, i.e. with draft-ietf-bfd-
> generic-crypto-auth available, whether or not we need to write
> standard-track draft for every authentication that BFD need to use
> going forward. Maybe I over-looked something ...
> 
> 
> (3) Section 2
> 
> Missing '.' chars.
> 
> [old]
>    B is the block size of H, measured in octets rather than bits.  Note
>    that B is the internal block size, not the hash size.  For SHA-1 and
>    SHA-256: B == 64 For SHA-384 and SHA-512: B == 128 L is the length
> of
>    the hash, measured in octets rather than bits.
> [new]
>    B is the block size of H, measured in octets rather than bits.  Note
>    that B is the internal block size, not the hash size.  For SHA-1 and
>    SHA-256: B == 64. For SHA-384 and SHA-512: B == 128. L is the length
>    of the hash, measured in octets rather than bits.
> [snip]
> 
> 
> -Nobo