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Re: [TLS] draft-ietf-tls-tls13-21: TLS 1.3 record padding removal leaks padding size

Nikos Mavrogiannopoulos <nmav@redhat.com> Fri, 11 August 2017 16:43 UTC

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From: Nikos Mavrogiannopoulos <nmav@redhat.com>
Date: Fri, 11 Aug 2017 18:43:15 +0200
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To: "Short, Todd" <tshort@akamai.com>
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Subject: Re: [TLS] draft-ietf-tls-tls13-21: TLS 1.3 record padding removal leaks padding size
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On Fri, Aug 11, 2017 at 5:17 PM, Short, Todd <tshort@akamai.com> wrote:

> The application can solve this by having its own padding. If it’s going to
> force all messages to be padded out to 1024 bytes by TLS, why not just make
> that part of the application protocol? Its not as though it’s trying to
> save bytes here.
>

I don't argue with this but this is not the approach TLS 1.3 took. It
provides a generic padding mechanism to be used across application
protocols.

regards,
Nikos

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