Re: [TLS] Encryption of TLS 1.3 content type

Yoav Nir <> Fri, 25 July 2014 20:57 UTC

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From: Yoav Nir <>
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Date: Fri, 25 Jul 2014 16:57:35 -0400
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To: "Joseph Salowey (jsalowey)" <>
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Subject: Re: [TLS] Encryption of TLS 1.3 content type
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I believe that changing the 5-byte record header will cause us trouble. Passive IDS/IPS devices follow TLS streams to detect certain attacks. They will cut connections. I also believe that it is impossible to “run some tests” because there are literally dozens of different such middleboxes, with multiple software/firmware versions available for each type.

I therefore support leaving the 5-byte header as it is, fixing the ContentType value to 23 for all encrypted records, and having another contentType byte within the encrypted record.


On Jul 25, 2014, at 1:37 PM, Joseph Salowey (jsalowey) <> 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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