OpenPGP smartcard and P-256 in non expert mode

[Sosthène Guédon | Nitrokey]

Hi!

I don't understand why generating a key on a smartcard only offers Curve25519 and P-384 for ECC cryptography unless the --expert flag is used.
P-384 is offered even when the hardware key doesn't support it and other curves which the hardware supports are not offered which is confusing.
Why is the P-256 curve disabled by default? It seems deliberate in https://git.gnupg.org/cgi-bin/gitweb.cgi?p=gnupg.git;a=commit;h=402aa0f94854bb00475c934be5ca6043a4632126
but I can't find any documentation on why that choice was made.

Thanks,
Sosthène

-- 
Sosthène Guédon
Intern

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