Re: [TLS] Encryption of TLS 1.3 content type

Colm MacCárthaigh <colm@allcosts.net> Sat, 26 July 2014 17:59 UTC

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Date: Sat, 26 Jul 2014 10:59:15 -0700
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From: =?UTF-8?Q?Colm_MacC=C3=A1rthaigh?= <colm@allcosts.net>
To: Watson Ladd <watsonbladd@gmail.com>
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Subject: Re: [TLS] Encryption of TLS 1.3 content type
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Leaking alert messages has been a recurring theme common to several
attacks; hindering a MITM's ability to discern alert messages seems
like a rational rationale.

On Sat, Jul 26, 2014 at 10:43 AM, Watson Ladd <watsonbladd@gmail.com> wrote:
> This is a change with no rationale: the content type leaks extremely
> limited information. It complicates implementations that wish to keep
> a high degree of codepath similarity between TLS 1.2 and TLS 1.3.
>
> On Fri, Jul 25, 2014 at 10:37 AM, Joseph Salowey (jsalowey)
> <jsalowey@cisco.com> wrote:
>> At the interim meeting on July 20, 2014 there was general consensus to support the encryption of TLS 1.3 content type.  The favored approach was to remove the content type and version from the TLS record layer header and add the content type to the encrypted data.   The proposal is to update the draft to document this approach and try to run some tests to see if this causes much grief with middle boxes.  If you object to this proposal please respond to the list by Friday, August 01, 2014.
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>
>
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-- 
Colm