Subject: [TLS] new extension - domain hint

From: "Joshua Ball" <[email-masked]>
Date: Wed, 2 Feb 2005 11:54:33 -0800

Hello,

I am creating a new TLS extension (a domain hint, sent by the client to
help the server map the clients certificate) and would like to ensure
some extension numbers and new handshake messages don't conflict with
any others. Do you have a protocol for choosing these numbers, or should
I just choose and submit to this list (and then an informational as
well).

If the latter, then here is what I suggest:
Currently, we need a new ExtensionType { client_domain(6) }
As well we need a new Handshake Message { client_domain_name(23) }

Otherwise, if these conflict with others, I am certainly open to
different numbers. 

As well, is there (or should there be) a list of known extensions and HS
messages?

Any thoughts? 

Thanks,
joshua

_______________________________________________
TLS mailing list
[email-masked]
https://www1.ietf.org/mailman/listinfo/tls

---

From: [email-masked]
Date: Thu, 3 Feb 2005 08:22:44 +0200

Joshua Ball writes:
> 
> Hello,
> 
> I am creating a new TLS extension (a domain hint, sent by the
> client to help the server map the clients certificate) and
> would like to ensure some extension numbers and new handshake
> messages don't conflict with any others. Do you have a
> protocol for choosing these numbers, or should I just choose
> and submit to this list (and then an informational as well).

According to RFC 3546, "requests to define new extensions
(including assigning extension and error alert numbers) must be
approved by IETF Standards Action". draft-ietf-tls-rfc3546bis-00 
changes this to "IETF Consensus".

RFC 2246 does not define the procedure for handshake message
numbers, but draft-ietf-tls-rfc2246-bis-09 says that "New
Handshake message type values MUST be defined via RFC 2434
Standards Action."

Since you're defining both an extension and a new handshake
message, the correct procedure would be to write an internet
draft (with the values left as "TBD"), and initiate standards
action as described in RFC 2026, Section 6.1.1.  When IESG
approves the draft as proposed standard, then the "TBDs" are 
replaced with the actual numbers.

Or this is at least how the official IETF procedure is
supposed to work. Sadly, this procedure is often ignored,
as this list of "TLS numbers used in various places" shows:
http://people.nokia.net/~pasi/tls-numbers.txt

So if you decide not to follow the official procedure,
at least don't use any number that's already on the list...

(Disclaimer: The list is totally unofficial, and the inclusion
of any particular value does not mean that the number is
"allocated" for that purpose. In some cases, it's more 
like "hall of shame" :-)

Best regards,
Pasi