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

Ted Lemon <mellon@fugue.com> Fri, 11 August 2017 15:39 UTC

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From: Ted Lemon <mellon@fugue.com>
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Date: Fri, 11 Aug 2017 11:39:23 -0400
In-Reply-To: <075C47B6-A601-441F-B881-A7F78648B5F1@akamai.com>
Cc: Nikos Mavrogiannopoulos <nmav@redhat.com>, "tls@ietf.org" <tls@ietf.org>
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 Aug 11, 2017, at 11:17 AM, 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.

The downside to this is that now you have to get it right in each protocol that does it, instead of getting it right once.

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