Re: Less Leaky ECDSA signature generation (in master)

NIIBE Yutaka via Gcrypt-devel <[email protected]> Mon, 31 Mar 2025 10:00:40 +0900
Newsgroups gmane.comp.encryption.gpg.libgcrypt.devel
Message-ID <[email protected]>
Hello,

Thank you for your correction.

On Fri, Mar 28, 2025 at 10:21:43AM +0900, I (NIIBE Yutaka) wrote:
> While, arbitrary integers can be represented in the MPI representation,
> for a specific curve, the finite field is the one of integers module P
> (P: a prime defined by the curve).  Thus, for an ECC point, we can keep
> the integer value in the range from 0 to P-1.  For an intermediate value
> of integer (like multiplication), 2*P is enough size.

Ian Goldberg wrote:
> Do you mean P^2, not 2*P, as the bound of the intermediate result of a
> multiplication?

Yes.  It means P^2.  (I tried to say: it is enough to have memory, which
size is 2 * size of P.)
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