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[TLS] Re: Ambiguity of TLS Certificate Compression (RFC 8879)

Muhammad Usama Sardar <muhammad_usama.sardar@tu-dresden.de> Thu, 12 February 2026 20:38 UTC

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Subject: [TLS] Re: Ambiguity of TLS Certificate Compression (RFC 8879)
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On 12.02.26 19:38, David Benjamin wrote:

> I think PR 1401 is similarly minimal, and is a better starting point 
> than PR 1407. It actually tries to define what those "..."s we use in 
> 8446 even mean. Without scoping that to specifically the "..."s, it's 
> actually just false.
I don't think it's false. In my understanding, "Handshake transcript" is 
for handshake messages only. For post-handshake mechanisms, there is 
"hashed authenticator transcript" [0].
> It claims the messages are taken from that sequence but, even without 
> extensions, post-handshake auth does something slightly funky.
Please elaborate what exactly you believe in post-handshake auth is funky.
> By scoping it to specifically the "..."s, it puts the sequence exactly 
> where we need it.
I believe it's completely unnecessary. "hashed authenticator transcript" 
already distinguishes it.
> I intentionally split the PRs up precisely to give a menu of different 
> starting points, depending on how much appetite folks had for changes. 
> If I had meant for it to be a single atomic starting point, I would 
> have uploaded one PR.

Sure, I've added a new sweet dish to the menu :) Folks may still like it 
after your starter and full heart surgery :)

-Usama


[0] https://www.rfc-editor.org/rfc/rfc9261#section-5.2.2-7.4

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