Subject: Re: [saag] Support for ECDSA and SHA-2 (SHA-256) in the SSHFP record

From: Jeffrey Hutzelman <[email-masked]>
Date: Mon, 01 Aug 2011 13:14:52 -0400

On Sat, 2011-07-30 at 20:54 -0400, Ondřej Surý wrote:
> Hi Damien,
> 
> On 30. 7. 2011, at 14:21, Damien Miller wrote:
> 
> > Thanks for starting work on this - SSHFP records for ECDSA keys were on
> > my TODO list, but I haven't yet got around to them.
> 
> > I briefly skimmed your draft - one question I have is whether it is
> > better to roll up all the ECDSA key types under one SSHFP RR type.
> > It would be quite ugly to have to allocate SSHFP RR type numbers for
> > each possible ECDSA curve type, but using a single one might make
> > exploitation of SHA256 preimage attacks easier.

Before we go any further, it's probably best to make it clear in advance
that we are _not_ talking about RR types at all.  SSHFP is and continues
to be a single RR type.  What we are talking about is values for the
"algorithm" field in the SSHFP RR data.

It's a bit late now, but if we'd made the algorithm field a string
containing the SSH public key algorithm name, we wouldn't be having this
discussion now. :-(

> I thought that secsh was concluded, but it seems that the mailing list
>  is still up.  Ccing there as well.

The WG did conclude, but this list is still active and is the
appropriate forum for discussing changes or enhancements to SSH or
related protocols.  I'm CC'ing this there, and moving saag to bcc only
so that people there see my first comment above.

-- Jeff