Re: [TLS] Conflict between TLS 1.1 (RFC4346) and Krb5 Cipher Suite (RFC2712)

Bodo Moeller wrote:

> It might be better to be more explicit here.  Your proposed text
> resolves the conflict, but could be puzzling to implementors who
> haven't seen the Kerberos or TLS_GSS ciphersuite specifications and
> don't quite know what you're talking about when you mention
> alternative methods of server authentication.  Here is a more
> elaborate proposal:
> 
>      This message is omitted if the agreed-upon key exchange method is
>      anonymous or uses an alternative method of server authentication.
>      For all non-anoymous key exchange methods specified in this
>      document, the server MUST send this message.  For non-anonymous
>      key exchange methods specified elsewhere that do not provide an
>      alternative method of server authentication, the server MUST send
>      this message.  This message will always immediately follow the
>      server hello message.
> 
> This also would clarify that you can't send a certificate message in
> an anonymous handshake, which apparently isn't strictly forbidden with
> the current language.  (The signature part of the ServerKeyExchange is
> empty, so there's no point in trying to attach a server certificate to
> a handshake that is nominally anonymous.)
> 
> Bodo

One more revision combining the best of Pasi's and Bodo's text:

     This message is omitted if the agreed-upon key exchange method is
     anonymous or uses server authentication method that does not
     involve certificates.  For all key exchange methods specified in
     this document except for DH_anon, the server MUST send this
     message.  For non-anonymous key exchange methods specified
     elsewhere that do not provide an alternative method of server
     authentication, the server MUST send this message.  This message
     will always immediately follow the server hello message.

Jeffrey Altman

Re: [TLS] Conflict between TLS 1.1 (RFC4346) and Krb5 Cipher Suite (RFC2712)

Attachment: smime.p7s