Ed25519 uses a different signature algorithm and is only specified for 
Curve25519 so that's not entirely surprising :-)


On 7 April 2014 18:55:28 Alex Gaynor <notifications@github.com> wrote:

> > +    A named `ECDSA`_ curve.
> > +
> > +    .. attribute:: name
> > +
> > +        :type: string
> > +
> > +        The name of the curve. Usually the name defined by SECG. e.g. 
> secp256k1
> > +
> > +    .. attribute:: key_size
> > +
> > +        :type: int
> > +
> > +        The bit length of the curves base point.
> > +
> > +
> > +.. class:: ECDSAPrivateKey
>
> As a point of reference, the go implementation of ed25519 doesn't use the
> ECDSA interfaces at all: https://github.com/agl/ed25519
>
>
> On Mon, Apr 7, 2014 at 10:53 AM, Alex Stapleton 
> <notifications@github.com>wrote:
>
> > In docs/hazmat/primitives/interfaces.rst:
> >
> > > +    A named `ECDSA`_ curve.
> > > +
> > > +    .. attribute:: name
> > > +
> > > +        :type: string
> > > +
> > > +        The name of the curve. Usually the name defined by SECG. e.g. 
> secp256k1
> > > +
> > > +    .. attribute:: key_size
> > > +
> > > +        :type: int
> > > +
> > > +        The bit length of the curves base point.
> > > +
> > > +
> > > +.. class:: ECDSAPrivateKey
> >
> > I'm not entirely sure I understand my self but I believe it's because they
> > generally use different representations of the curve. While it's possible
> > to convert between representations apparently that has some implications on
> > how point addition works? Generally it just seems to be a thing that people
> > don't do. Instead of ECDSA you use the Ed25519 construct for signatures.
> > … <#1453d52f17efc608_>
> > On 7 April 2014 18:46:05 Matt Iversen <notifications@github.com> wrote: >
> > + A named `ECDSA`_ curve. > + > + .. attribute:: name > + > + :type: string
> > > + > + The name of the curve. Usually the name defined by SECG. e.g.
> > secp256k1 > + > + .. attribute:: key_size > + > + :type: int > + > + The
> > bit length of the curves base point. > + > + > +.. class:: ECDSAPrivateKey
> > Why can't you use Curve25519 under ECDSA? --- Reply to this email directly
> > or view it on GitHub:
> > https://github.com/pyca/cryptography/pull/878/files#r11355645
> >
> > —
> > Reply to this email directly or view it on 
> GitHub<https://github.com/pyca/cryptography/pull/878/files#r11356063>
> > .
> >
>
>
>
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