Re: [TLS] PR#28: Converting cTLS to QUIC-style varints

Martin Thomson <mt@lowentropy.net> Tue, 06 October 2020 06:52 UTC

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Date: Tue, 06 Oct 2020 17:52:15 +1100
From: "Martin Thomson" <mt@lowentropy.net>
To: tls@ietf.org
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Subject: Re: [TLS] PR#28: Converting cTLS to QUIC-style varints
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On Tue, Oct 6, 2020, at 17:36, Hannes Tschofenig wrote:
> In the work on QUIC did you discuss the ability to make the encoding 
> such that there are no ways to express a number in two different ways, 
> as shown in your example with the single byte 25 decoding to 37 and the 
> two byte sequence 40 25? 

For QUIC, where the performance impact of serialization and parsing was considered important, the additional cost involved was a little higher than I think some people wanted.  It also makes the encoding more complex.

A "distinguished" or canonical encoding wasn't critical there.  It's probably not critical here either.