Re: [TLS] TLS 1.3 Record Boundaries
Ilari Liusvaara <ilariliusvaara@welho.com> Tue, 24 October 2017 12:53 UTC
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Date: Tue, 24 Oct 2017 15:53:50 +0300
From: Ilari Liusvaara <ilariliusvaara@welho.com>
To: Andrei Popov <Andrei.Popov@microsoft.com>
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Subject: Re: [TLS] TLS 1.3 Record Boundaries
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On Tue, Oct 24, 2017 at 12:42:01AM +0000, Andrei Popov wrote: > Draft-21 says: > "Handshake messages MUST NOT span key changes. Implementations > MUST verify that all messages immediately preceding a key change > align with a record boundary; if not, then they MUST terminate the > connection with an "unexpected_message" alert. Because the > ClientHello, EndOfEarlyData, ServerHello, Finished, and KeyUpdate > messages can immediately precede a key change, implementations > MUST send these messages in alignment with a record boundary." Edge case: Finished is also part of post-handshake auth (*puke*), which does not trigger key change. And from some cryptographic analysis, one might get an idea to immediately send a KeyUpdate requesting reciproal update afterwards (not that I think that is actually necressary or even helpful). -Ilari
- [TLS] TLS 1.3 Record Boundaries Andrei Popov
- Re: [TLS] TLS 1.3 Record Boundaries Peter Wu
- Re: [TLS] TLS 1.3 Record Boundaries Ilari Liusvaara
- Re: [TLS] TLS 1.3 Record Boundaries Hubert Kario