Re: [Dcrup] rsa-sha1 usage

["Murray S. Kucherawy" <[e-mail]>]

On Tue, Jun 13, 2017 at 9:18 PM, Jim Fenton <[e-mail]> wrote:

> As Pete Resnick loves to point out, RFC prose can be normative without
> using RFC2119 words.
>
> The text of RFC2119 counsels against unnecessary use of the words it
> defines.  It also contains this language: "...actually required for
> interoperation" (which use of rsa-sha1 clearly does not impede) "or to
> limit behavior which has potential for causing harm".  I suppose this
> latter is the key issue.
>
>
> With respect to whether you need to include the MUST NOT (a point you made
> earlier), I'll defer to whatever the accepted practices are on the wording.
>
> But WRT the potential to cause harm, I refer to ekr's comment:
>
> Well, this would require a second preimage. My sense is that nobody is
> close to that at all with SHA-1....
>
> which I interpret as little potential for causing harm in the near future.
>

This actually leads me to believe that there's no urgency to deprecate
rsa-sha1 at all.


> P.S. It would be helpful for you to identify which of your comments are
> made as chair and which are made hats-off.
>

Unless you see me explicitly saying the hat is on, especially in a
technical discussion, the hat is always off.  I'm participating.

I don't think it's ever appropriate for a chair to make hatted assertions
about technical topics unless being called on to make a decision when the
WG is deadlocked, and that should be exceptional.  In the chair role, we
just run the process.

-MSK