Re: [TLS] draft-ietf-tls-esni feedback

[Eric Rescorla <[e-mail]>]

On Mon, Oct 21, 2019 at 7:32 AM Rob Sayre <[e-mail]> wrote:



> Judging by the mailing list archives, the design of the field is
>>> intentional. It's not clear to me why "zeros" wasn't specified as
>>> variable-length with a prose restriction, though.
>>>
>>
>> Because then you have a spurious length field.
>>
>
> I don't understand why it would be spurious. In this case, the
> deserializing implementation needs to inspect every byte anyway.
>

Because if you set padding to be the length of the maximum value, then a
length byte makes every message one longer.



>
>> This part of the spec is also just generally difficult to follow, in my
>>> opinion. I had no trouble following the ESNIKeys section. Perhaps the
>>> problem is in the interaction of prose order, serialization order, and
>>> procedural code order.
>>>
>>
>> Well, this structure is likely to change a fair bit, so probably not
>> worth trying to update the text right at this moment.
>>
>
> Fair enough. I would also suggest making sure that this section does not
> span a page boundary. That made things worse for me.
>

At this early stage, we usually don't worry over-much about page breaks.

-Ekr


> thanks,
> Rob
>