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Re: [TLS] TLS 1.3 and max_fragment_length

Martin Thomson <martin.thomson@gmail.com> Tue, 14 March 2017 21:27 UTC

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From: Martin Thomson <martin.thomson@gmail.com>
Date: Wed, 15 Mar 2017 08:27:41 +1100
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To: Benjamin Kaduk <bkaduk@akamai.com>
Cc: Yoav Nir <ynir.ietf@gmail.com>, Ilari Liusvaara <ilariliusvaara@welho.com>, "tls@ietf.org" <tls@ietf.org>
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Subject: Re: [TLS] TLS 1.3 and max_fragment_length
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On 15 March 2017 at 07:44, Benjamin Kaduk <bkaduk@akamai.com> wrote:
>    The presence of padding does not change the overall record size
>    limitations - the full fragment plaintext may not exceed 2^14 octets. If
>
>    the maximum fragment length is reduced, such as by the
>
>    max_fragment_length extension from [RFC6066], then the reduced limit
>
>    applies to the full plaintext, including the padding.

Sounds good, I've created a PR.  I also changed the "may" to a  "MUST"
on the basis that this is an interoperability requirement.

https://github.com/tlswg/tls13-spec/pull/909

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