Is X25519/X448 supported for TLSv1.2?

[Viktor Dukhovni]

On Wed, Jun 12, 2019 at 05:31:30PM +0800, John Jiang wrote:

> > > Tried below commands,
> > > openssl s_server -trace -state -cert server.cer -key server.key -accept port
> > > openssl s_client -trace -state -CAfile ca.cer -tls1_2 -groups X25519 -connect localhost:port
> >
> > With same commands, using OpenSSL 1.1.1c, I get:
> >
> >     CONNECTION ESTABLISHED
> >     Protocol version: TLSv1.2
> >     Ciphersuite: ECDHE-RSA-AES256-GCM-SHA384
> >     Peer certificate:
> >     Hash used: SHA256
> >     Signature type: RSA-PSS
> >     Supported Elliptic Curve Point Formats: ...
> >     Server Temp Key: X25519, 253 bits
> >
> > Perhaps your s_client is not the one from 1.1.1 or it is dynamically
> > linked against 1.1.0 libraries...
> >
> My s_client can support TLSv1.3, so it should not be from any pre-1.1.1
> version.

You say that, but the evidence suggests otherwise.  In each of
whatever shells you're using to start the client and server,
it would be prudent to run:

    $ openssl version -v

Here's an example with the command and library at the same version:

    $ /usr/local/bin/openssl version -v
    OpenSSL 1.1.1c  28 May 2019

And here's another where they differ in the patchlevel:

    $ LD_PRELOAD=/lib/libcrypto.so.111:/usr/lib/libssl.so.111 /usr/local/bin/openssl version -v
    OpenSSL 1.1.1c  28 May 2019 (Library: OpenSSL 1.1.1a-freebsd  20 Nov 2018)

Without forcing anything with LD_PRELOAD, ... are your client and
server in fact 1.1.1 in both the executable and the library?

-- 
	Viktor.