Re: [jose] CFRG ECC in JOSE - thumbprint

[Ilari Liusvaara <[e-mail]>]

On Sat, Nov 14, 2015 at 04:43:27PM +0100, Anders Rundgren wrote:
> Hi Ilari,
> 
> If these curves are generally recognized as "Edwards" (?) I would personally prefer
> that "kty" refer to something Edward-ish like "ED" although this is (of course)
> entirely unimportant.

These things are not Edwards curves. These things are abstract public-key
algorithms.

If you truly had Edwards curve over prime field[1], there would be no
problem presenting it in standard "EC" notation, as these things have
well-defined curve and both x and y coordinates that are in Z_p.


And yes, I did consider reusing "crv" and "x", but decided that looks
pretty odd (there is no guarantee that these things are in any way
based on elliptic curves, nor that even if they are, "x" is actually
x coordinate of the curve.


[1] But this fails for Edwards curves over prime squared fields, since
each co-ordinate has two subcomponents (AFAIK, higher powers give
weak-for-ECC fields). 



-Ilari