Re: [CFRG] Handling the errata for RFC 7748

[Adam Langley <[e-mail]>]

On Wed, Dec 9, 2020 at 10:50 PM Stanislav V. Smyshlyaev <[e-mail]>
wrote:

> Dear CFRG,
>
> There are three reported errata for RFC 7748:
> https://www.rfc-editor.org/errata/eid5568
> https://www.rfc-editor.org/errata/eid5651
> https://www.rfc-editor.org/errata/eid5028
>
> The third one (5028) is an editorial one, I am sure that it improves
> clarity of the text, therefore, I support it without doubt.
>
> The first one (5568) is a technical one, with a proposal to change one bit
> of the input u-coordinate in the hexadecimal representation (to make it
> "consistent" with the base 10 representation). However, the author of 5568
> has probably missed that implementations of x25519 should "mask" that bit
> after taking a u-coordinate as an input - therefore, the existing text of
> RFC does not have any errors there. This is exactly the result of unclear
> text that is addressed in the abovementioned third erratum
> (5028).Therefore, I would propose to reject the erratum.
>
> The second one (5651) notes that the algorithm description has a mistake
> in the description (for calculation of z_2). After implementing the
> described algorithm myself (with the MAGMA package) I've obtained the
> expected numbers. I suspect that the RFC text is OK, –therefore I would
> propose to reject the erratum.
>
> Therefore, I'm planning to approve the third one (5028) and reject the
> other two errata (5568 and 5651).
>

I agree with all of the above. Thanks for checking them.


AGL