EAP-TLS with TLS 1.3

Stefan Winter stefan.winter at restena.lu
Mon Mar 12 11:40:15 CET 2018


I'm currently looking at

It states that:

   While Elliptic Curve Cryptography (ECC) was optional for earlier
   version of TLS, TLS 1.3 mandates support of ECC (see Section 9 of
   [I-D.ietf-tls-tls13]).  To avoid fragmentation, the use of ECC in
   certificates, signature algorithms, and groups are RECOMMENDED when
   using EAP-TLS with TLS 1.3 or higher.

That sounds like useful avice.

I'm wondering though what to do if you have a diverse variety of client
devices doing EAP; some of which only do TLS 1.2 while others do TLS 1.3.

The EAP server can only present one certificate to its incoming peer

If it has a ECDSA certificate, there's a chance for an interop problem
with TLS 1.2 clients not supporting the needed cipher suites.

If it has a RSA certificate, it misses out on the small-cert benefits.

I wonder if it's possible to have both certificates available to the
server, with a late selection: depending on which TLS version has been
negotiated, present one cert or the other.

Is that kind of stuff doable?

It would certainly make a transition easier...


Stefan Winter

Ingenieur de Recherche
Fondation RESTENA - Réseau Téléinformatique de l'Education Nationale et
de la Recherche
2, avenue de l'Université
L-4365 Esch-sur-Alzette

Tel: +352 424409 1
Fax: +352 422473

PGP key updated to 4096 Bit RSA - I will encrypt all mails if the
recipient's key is known to me

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: OpenPGP digital signature
URL: <http://lists.freeradius.org/pipermail/freeradius-devel/attachments/20180312/85f8cef5/attachment.sig>

More information about the Freeradius-Devel mailing list