Re: Double-checking with NUMS and Curve 25519 [was Re: Elliptic Curve Extensibility - your view is expected]

On Fri, Oct 17, 2014 at 4:39 PM, Mrk Watson <watsonm@netflix.com> wrote:
>
>
> On Fri, Oct 17, 2014 at 4:16 PM, Trevor Perrin <trevp@trevp.net> wrote:
>>
>> You're also assuming the JWK "EC" type, which requires full x and y
>> coordinates, so disallows single-coordinate or compressed public keys.
>
>
> Do you think they would use a different "kty" value if JWK was extended for
> single-coordinate or compressed public keys ?

I joined one call about 25519, and I think Mike Jones suggested
defining a different "kty" for 25519, instead of trying to change the
"EC" type.

So I don't know what the best representation of compressed Edwards or
single-coordinate Montgomery points in JWK is.  I guess I'd leave that
decision to a new algorithm.


>> Those could be fixed - whether all this is saving any effort or
>> cleaner than just defining new algorithms, I don't have strong
>> opinions on.
>
>
> I don't much care either, myself, but others have expressed strong opinions
> in the past that adding to the NamedCurve list is superior to defining new
> algorithms and noone has expressed the converse opinion.

I weakly prefer just defining new algorithms, I think these extension
points messy-up the text; they replace almost all the substance of the
existing algorithms; and if they're not exactly right we'll need new
algorithms anyways.


Trevor

Received on Friday, 17 October 2014 23:57:00 UTC