On Thu, Jun 13, 2019 at 12:28 PM Viktor Dukhovni <openssl-users@xxxxxxxxxxxx> wrote:
On Thu, Jun 13, 2019 at 10:49:14AM +0800, John Jiang wrote:
> I got the point: the server certificate is ECDSA with curve secp256r1.
> It works with RSA certificate and curves
> sepc256r1/sepc384r1/sepc521r1/x25519/x448.
See https://github.com/openssl/openssl/issues/4175#issuecomment-322915924
When using ECDSA with TLSv1.2, the group list MUST include the group
used in the certificate. Otherwise, you get no shared cipher as
you reported.
How about this point in TLSv1.3?
With my testing, the case "ECDSA certificate with curve secp256r1 + named group secp521r1" work fine with OpenSSL s_server and s_client.
You can *prefer* X25519, but you cannot only offerJust an intentional test.
X25519.
