Re: [TLS] ESNI padding the Certificate message

Stephen Farrell <stephen.farrell@cs.tcd.ie> Thu, 13 December 2018 13:54 UTC

Return-Path: <stephen.farrell@cs.tcd.ie>
X-Original-To: tls@ietfa.amsl.com
Delivered-To: tls@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id ED0F01271FF for <tls@ietfa.amsl.com>; Thu, 13 Dec 2018 05:54:55 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -4.301
X-Spam-Level:
X-Spam-Status: No, score=-4.301 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, RCVD_IN_DNSWL_MED=-2.3, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=cs.tcd.ie
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 QyhLexp3X1pd for <tls@ietfa.amsl.com>; Thu, 13 Dec 2018 05:54:53 -0800 (PST)
Received: from mercury.scss.tcd.ie (mercury.scss.tcd.ie [134.226.56.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 88D631252B7 for <tls@ietf.org>; Thu, 13 Dec 2018 05:54:52 -0800 (PST)
Received: from localhost (localhost [127.0.0.1]) by mercury.scss.tcd.ie (Postfix) with ESMTP id 878D0BE55; Thu, 13 Dec 2018 13:54:50 +0000 (GMT)
Received: from mercury.scss.tcd.ie ([127.0.0.1]) by localhost (mercury.scss.tcd.ie [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id e8PAa52Pv8lP; Thu, 13 Dec 2018 13:54:50 +0000 (GMT)
Received: from [134.226.36.93] (bilbo.dsg.cs.tcd.ie [134.226.36.93]) by mercury.scss.tcd.ie (Postfix) with ESMTPSA id 3758BBE53; Thu, 13 Dec 2018 13:54:50 +0000 (GMT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cs.tcd.ie; s=mail; t=1544709290; bh=grFrS9qQQBu8GaR2Ts9KSH+OLZgd/U4GNzb2Fbly5E0=; h=Subject:To:References:From:Date:In-Reply-To:From; b=RboAS11iAhjK0ct+h86xRC56zKOWIdH0/v53hAoMo4rfKI1dgCwL48blyK+jZzvE6 Zt7PrGPsTOSouCsDLSwgVrl7w6SMx88TxMn3Pt5GhQEXFDCpyfa5cik+FRri4k1gc6 rTylvHaeezB3hmvzX0hCK25hT8Yonc+OVhmUUynA=
To: Matt Caswell <matt@openssl.org>, tls@ietf.org
References: <876187a2-df66-2eb0-5a55-b6e67cf668f6@cs.tcd.ie> <ed463806-067d-bd83-f186-2ef6f5bd3518@openssl.org>
From: Stephen Farrell <stephen.farrell@cs.tcd.ie>
Openpgp: id=5BB5A6EA5765D2C5863CAE275AB2FAF17B172BEA; url=
Autocrypt: addr=stephen.farrell@cs.tcd.ie; prefer-encrypt=mutual; keydata= mQINBFo9UDIBEADUH4ZPcUnX5WWRWO4kEkHea5Y5eEvZjSwe/YA+G0nrTuOU9nemCP5PMvmh 5Cg8gBTyWyN4Z2+O25p9Tja5zUb+vPMWYvOtokRrp46yhFZOmiS5b6kTq0IqYzsEv5HI58S+ QtaFq978CRa4xH9Gi9u4yzUmT03QNIGDXE37honcAM4MOEtEgvw4fVhVWJuyy3w//0F2tzKr EMjmL5VGuD/Q9+G/7abuXiYNNd9ZFjv4625AUWwy+pAh4EKzS1FE7BOZp9daMu9MUQmDqtZU bUv0Q+DnQAB/4tNncejJPz0p2z3MWCp5iSwHiQvytYgatMp34a50l6CWqa13n6vY8VcPlIqO Vz+7L+WiVfxLbeVqBwV+4uL9to9zLF9IyUvl94lCxpscR2kgRgpM6A5LylRDkR6E0oudFnJg b097ZaNyuY1ETghVB5Uir1GCYChs8NUNumTHXiOkuzk+Gs4DAHx/a78YxBolKHi+esLH8r2k 4LyM2lp5FmBKjG7cGcpBGmWavACYEa7rwAadg4uBx9SHMV5i33vDXQUZcmW0vslQ2Is02NMK 7uB7E7HlVE1IM1zNkVTYYGkKreU8DVQu8qNOtPVE/CdaCJ/pbXoYeHz2B1Nvbl9tlyWxn5Xi HzFPJleXc0ksb9SkJokAfwTSZzTxeQPER8la5lsEEPbU/cDTcwARAQABtDJTdGVwaGVuIEZh cnJlbGwgKDIwMTcpIDxzdGVwaGVuLmZhcnJlbGxAY3MudGNkLmllPokCQAQTAQgAKgIbAwUJ CZQmAAULCQgHAgYVCAkKCwIEFgIDAQIeAQIXgAUCWj6jdwIZAQAKCRBasvrxexcr6o7QD/9m x9DPJetmW794RXmNTrbTJ44zc/tJbcLdRBh0KBn9OW/EaAqjDmgNJeCMyJTKr1ywaps8HGUN hLEVkc14NUpgi4/Zkrbi3DmTp25OHj6wXBS5qVMyVynTMEIjOfeFFyxG+48od+Xn7qg6LT7G rHeNf+z/r0v9+8eZ1Ip63kshQDGhhpmRMKu4Ws9ZvTW2ACXkkTFaSGYJj3yIP4R6IgwBYGMz DXFX6nS4LA1s3pcPNxOgrvCyb60AiJZTLcOk/rRrpZtXB1XQc23ZZmrlTkl2HaThL6w3YKdi Ti1NbuMeOxZqtXcUshII45sANm4HuWNTiRh93Bn5bN6ddjgsaXEZBKUBuUaPBl7gQiQJcAlS 3MmGgVS4ZoX8+VaPGpXdQVFyBMRFlOKOC5XJESt7wY0RE2C8PFm+5eywSO/P1fkl9whkMgml 3OEuIQiP2ehRt/HVLMHkoM9CPQ7t6UwdrXrvX+vBZykav8x9U9M6KTgfsXytxUl6Vx5lPMLi 2/Jrsz6Mzh/IVZa3xjhq1OLFSI/tT2ji4FkJDQbO+yYUDhcuqfakDmtWLMxecZsY6O58A/95 8Qni6Xeq+Nh7zJ7wNcQOMoDGj+24di2TX1cKLzdDMWFaWzlNP5dB5VMwS9Wqj1Z6TzKjGjru q8soqohwb2CK9B3wzFg0Bs1iBI+2RuFnxLkCDQRaPVAyARAA+g3R0HzGr/Dl34Y07XqGqzq5 SU0nXIu9u8Ynsxj7gR5qb3HgUWYEWrHW2jHOByXnvkffucf5yzwrsvw8Q8iI8CFHiTYHPpey 4yPVn6R0w/FOMcY70eTIu/k6EEFDlDbs09DtKcrsT9bmN0XoRxITlXwWTufYqUnmS+YkAuk+ TLCtUin7OdaS2uU6Ata3PLQSeM2ZsUQMmYmHPwB9rmf+q2I005AJ9Q1SPQ2KNg/8xOGxo13S VuaSqYRQdpV93RuCOzg4vuXtR+gP0KQrus/P2ZCEPvU9cXF/2MIhXgOz207lv3iE2zGyNXld /n8spvWk+0bH5Zqd9Wcba/rGcBhmX9NKKDARZqjkv/zVEP1X97w1HsNYeUFNcg2lk9zQKb4v l1jx/Uz8ukzH2QNhU4R39dbF/4AwWuSVkGW6bTxHJqGs6YimbfdQqxTzmqFwz3JP0OtXX5q/ 6D4pHwcmJwEiDNzsBLl6skPSQ0Xyq3pua/qAP8MVm+YxCxJQITqZ8qjDLzoe7s9X6FLLC/DA L9kxl5saVSfDbuI3usH/emdtn0NA9/M7nfgih92zD92sl1yQXHT6BDa8xW1j+RU4P+E0wyd7 zgB2UeYgrp2IIcfG+xX2uFG5MJQ/nYfBoiALb0+dQHNHDtFnNGY3Oe8z1M9c5aDG3/s29QbJ +w7hEKKo9YMAEQEAAYkCJQQYAQgADwUCWj1QMgIbDAUJCZQmAAAKCRBasvrxexcr6qwvD/9b Rek3kfN8Q+jGrKl8qwY8HC5s4mhdDJZI/JP2FImf5J2+d5/e8UJ4fcsT79E0/FqX3Z9wZr6h sofPqLh1/YzDsYkZDHTYSGrlWGP/I5kXwUmFnBZHzM3WGrL3S7ZmCYMdudhykxXXjq7M6Do1 oxM8JofrXGtwBTLv5wfvvygJouVCVe87Ge7mCeY5vey1eUi4zSSF1zPpR6gg64w2g4TXM5qt SwkZVOv1g475LsGlYWRuJV8TA67yp1zJI7HkNqCo8KyHX0DPOh9c+Sd9ZX4aqKfqH9HIpnCL AYEgj7vofeix7gM3kQQmwynqq32bQGQBrKJEYp2vfeO30VsVx4dzuuiC5lyjUccVmw5D72J0 FlGrfEm0kw6D1qwyBg0SAMqamKN6XDdjhNAtXIaoA2UMZK/vZGGUKbqTgDdk0fnzOyb2zvXK CiPFKqIPAqKaDHg0JHdGI3KpQdRNLLzgx083EqEc6IAwWA6jSz+6lZDV6XDgF0lYqAYIkg3+ 6OUXUv6plMlwSHquiOc/MQXHfgUP5//Ra5JuiuyCj954FD+MBKIj8eWROfnzyEnBplVHGSDI ZLzL3pvV14dcsoajdeIH45i8DxnVm64BvEFHtLNlnliMrLOrk4shfmWyUqNlzilXN2BTFVFH 4MrnagFdcFnWYp1JPh96ZKjiqBwMv/H0kw==
Message-ID: <a82f0a2c-1bca-df31-1615-45e87391c053@cs.tcd.ie>
Date: Thu, 13 Dec 2018 13:54:47 +0000
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1
MIME-Version: 1.0
In-Reply-To: <ed463806-067d-bd83-f186-2ef6f5bd3518@openssl.org>
Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="q5ujsjXN9C8fKksayW6DTb1MkGPqQZYAY"
Archived-At: <https://mailarchive.ietf.org/arch/msg/tls/7OMBsvRQ51Fy2LlsCjaaFRgsk3w>
Subject: Re: [TLS] ESNI padding the Certificate message
X-BeenThere: tls@ietf.org
X-Mailman-Version: 2.1.29
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: Thu, 13 Dec 2018 13:54:56 -0000


On 13/12/2018 13:36, Matt Caswell wrote:
> You can set a padding callback using SSL_CTX_set_record_padding_callback() (or
> SSL_set_record_padding_callback()). The callback can determine whether it is
> padding a handshake message by examining its "type" parameter, and which message
> it is by calling SSL_get_state(). From there you should be able to get the
> callback to add padding only to the Certificate and/or CertificateVerify
> messages as required.

Thanks! I'll try that,
S.