[OpenTRV-dev] Christmas secure protocol joy!

[Damon Hart-Davis]

Hi,

Thanks for the analysis.  Yes, all variable-length fields are immediately preceded by their length.

Rgds

Damon

> On 29 Dec 2015, at 12:49, Jeremy Poulter <jeremy at bigjungle.net> wrote:
> 
> If I am reading it correctly you have the total packet length (including the body) as the first byte so I am OK with the body size immediately proceeding the body data and in general this should be the same format for all variable length fields (no checked this is the case in detail).
> 
> Just my 2p worth.
> 
> Jeremy
> 
> On 24 Dec 2015 10:27, "Damon Hart-Davis" <damon at opentrv.uk> wrote:
> Hi,
> 
> http://www.earth.org.uk/OpenTRV/stds/network/20151203-DRAFT-SecureBasicFrame.txt
> 
> Matthew W suggests that parsing (etc) might be significantly easier if the body length field was moved up somewhere in front of the variable-length ID field (or if the ID length was fixed, but I’m pretty certain that I don’t want to take that path).
> 
> I’m loathe to separate the body length from the body, but I’m interested in other views on this.  Simplicity in parsing/generating is very valuable for the sorts of small systems that this protocol is aimed at.
> 
> Will Santa bring us a working protocol?  B^>
> 
> Rgds
> 
> Damon