Re: [TLS] Update on TLS 1.3 Middlebox Issues

Hannes Tschofenig <hannes.tschofenig@gmx.net> Tue, 10 October 2017 09:12 UTC

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To: mrex@sap.com, Ilari Liusvaara <ilariliusvaara@welho.com>
Cc: Adam Langley <agl@imperialviolet.org>, "tls@ietf.org" <tls@ietf.org>
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From: Hannes Tschofenig <hannes.tschofenig@gmx.net>
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Date: Tue, 10 Oct 2017 11:11:59 +0200
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Subject: Re: [TLS] Update on TLS 1.3 Middlebox Issues
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Hi Martin,

On 10/10/2017 10:52 AM, Martin Rex wrote:
> Nope, none at all.  I'm _not_ asking for protocol changes, just that
> the TLS handshake continues to end with CCS + HS, and ContentTypes
> remain visible.  Contents of all handshake messages, and whether
> and how that content is protected, remains subject to negotiated
> protocol version which may vary significantly.

FWIW: Making the ContentType visible is a protocol change since the
current version of the TLS / DTLS 1.3 protocol encrypts them.

Ciao
Hannes

PS: I think sending fake ChangeCipherSpec messages around is a terrible
idea.