[noise] Transport protocol spec finalizing

[Alexey Ermishkin]

Yes, echoing last version by default is probably the best option here. Otherwise it’s just reserved bytes needed for simplification of packet processing.

Will add this to spec if no objections

-----Original Message-----
From: Trevor Perrin [mailto:trevp at trevp.net] 
Sent: Thursday, July 13, 2017 2:19 PM
To: Alexey Ermishkin <scratch.net at gmail.com>
Cc: noise <noise at moderncrypto.org>
Subject: Re: [noise] Transport protocol spec finalizing

On Thu, Jul 13, 2017 at 7:36 AM, Alexey Ermishkin <scratch.net at gmail.com> wrote:
> Ok, makes sense. But we would still like to simplify handshake parsing and make a clear separation from transport messages.
>
> How about adding those fields (version, negotiation_data len) to the third packet? So that all handshake packets had the same structure.

We'd have to specify the rules for these fields.

For example, to match the behavior of client_version and server_version, maybe requiring later version fields match the previous version is best?

I don't have a strong opinion on this.  It's a little more complex, so we should try to write it up and make sure it's not too complicated.

It would also be good if we could think of examples uses for it.

Trevor