IETF Logo Mail Archive

Re: [TLS] Headerless records (was: padding)

Martin Thomson <martin.thomson@gmail.com> Tue, 25 August 2015 07:02 UTC

Return-Path: <martin.thomson@gmail.com>
X-Original-To: tls@ietfa.amsl.com
Delivered-To: tls@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id A82DD1A8AFE for <tls@ietfa.amsl.com>; Tue, 25 Aug 2015 00:02:44 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2
X-Spam-Level:
X-Spam-Status: No, score=-2 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, FREEMAIL_FROM=0.001, SPF_PASS=-0.001] autolearn=ham
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id YSA7aOglJRkl for <tls@ietfa.amsl.com>; Tue, 25 Aug 2015 00:02:43 -0700 (PDT)
Received: from mail-yk0-x229.google.com (mail-yk0-x229.google.com [IPv6:2607:f8b0:4002:c07::229]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 9C69E1A1B8A for <tls@ietf.org>; Tue, 25 Aug 2015 00:02:43 -0700 (PDT)
Received: by ykll84 with SMTP id l84so146213573ykl.0 for <tls@ietf.org>; Tue, 25 Aug 2015 00:02:43 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=oz8gDCgtZOHNtW9ppzqhJisgtV1zReIdNN75J675Ces=; b=Z5ltqkBBQMY4QU22zPIaKTPvjsDrWxGkWrTOl4QjgSr/AR0DpWqKFvTQab54Y6/rw/ V3nEyOzWZ5ZPyjNBVeURKHRQrNbn0r2UXBjVi0hWQjB9KpMH7e5EiQy9q+q4FIZlgvBC 75ThIUT4lQBAXEcJmWi8DZNORd1Oqf0OGHvJEHVg1JXY8+KjO/lbU7FO2WNMhG8eWdxG C/xDlRhUM+1lfiip6zxmLkBK23881Ejg0E7PA4mLXcTlRfj5wcwCL0uDhI8WMiYfDGDR d4xcaB/JGC1A7hcc7aazKjKvwdnj2xUHP7gg6EDYQUXP/bQLmpK+ORJC2RCsc0RhcoBB EsRw==
MIME-Version: 1.0
X-Received: by 10.13.225.66 with SMTP id k63mr35892625ywe.148.1440486162950; Tue, 25 Aug 2015 00:02:42 -0700 (PDT)
Received: by 10.129.133.130 with HTTP; Tue, 25 Aug 2015 00:02:42 -0700 (PDT)
In-Reply-To: <201508250004.36291.davemgarrett@gmail.com>
References: <CAH8yC8nQKzht4g6+FwvmN1ULCz3a+2j=0UF4h=8h71XbcVjFDQ@mail.gmail.com> <201508222028.46145.davemgarrett@gmail.com> <CA+cU71kS=x7_hVRXb8Q8m=DmqMaM65GaEn1SnzH_fQHP9mzyqA@mail.gmail.com> <201508250004.36291.davemgarrett@gmail.com>
Date: Tue, 25 Aug 2015 00:02:42 -0700
Message-ID: <CABkgnnX+S5De7pBC_VChz15daNcSpxgF6_ofxdPAv2vhpFigSg@mail.gmail.com>
From: Martin Thomson <martin.thomson@gmail.com>
To: Dave Garrett <davemgarrett@gmail.com>
Content-Type: text/plain; charset=UTF-8
Archived-At: <http://mailarchive.ietf.org/arch/msg/tls/biM87Mb1MJ9cCSyL17avp9a9cZw>
Cc: IETF TLS <tls@ietf.org>
Subject: Re: [TLS] Headerless records (was: padding)
X-BeenThere: tls@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: "This is the mailing list for the Transport Layer Security working group of the IETF." <tls.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/tls>, <mailto:tls-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/tls/>
List-Post: <mailto:tls@ietf.org>
List-Help: <mailto:tls-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/tls>, <mailto:tls-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 25 Aug 2015 07:02:44 -0000

On 24 August 2015 at 21:04, Dave Garrett <davemgarrett@gmail.com> wrote:
>         uint16 length = TLSPlaintext.length;

You can't recover the plaintext without knowing how long it is.  This
part at a minimum needs to be in the clear.  At which point you need
it to be based on TLSCiphertext.length

v2.1.27 | Report a Bug | By Email