Re: [openpgp] Curve448 in ECDH

Paul Wouters <paul@nohats.ca> Sun, 28 February 2021 17:09 UTC

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Date: Sun, 28 Feb 2021 12:09:28 -0500 (EST)
From: Paul Wouters <paul@nohats.ca>
To: "brian m. carlson" <sandals@crustytoothpaste.net>
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Subject: Re: [openpgp] Curve448 in ECDH
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On Sat, 27 Feb 2021, brian m. carlson wrote:

> I'm wondering, however, if there's consensus for adding Curve448 as well

That is being tracked by the WG chairs.

> The reason I ask is that in many implementations, of the NIST curves,
> only P-256 is implemented in a constant-time manner, whereas Curve25519
> and Curve448 are almost always implemented in a constant-time manner.

Is that a concern for openpgp ? openpgp is not an interactive protocol
where there is a server-client with possible MITM observing time spent?

Paul