[TLS] ech/esni - theoretically some inner CH's wouldn't fit...

Stephen Farrell <stephen.farrell@cs.tcd.ie> Sat, 20 February 2021 20:19 UTC

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From: Stephen Farrell <stephen.farrell@cs.tcd.ie>
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Date: Sat, 20 Feb 2021 20:19:26 +0000
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Subject: [TLS] ech/esni - theoretically some inner CH's wouldn't fit...
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Hiya,

The CH in TLS has a 3 octet length. The payload in ECH has a
2-octet length. Hopefully that'll never matter but it's an
inconsistency I don't recall coming up before. (Apologies if
I've forgotten, or if I've missed something in 8446 that
forbids bigger CH's.)

I'm fine with just leaving it as-is, or with noting in the
text that you will suffer this problem (and many others;-) if
you want to use a CH that's that long, or with moving to a 3
octet length for the payload.

Cheers,
S.