Re: [TLS] Last call comments and WG Chair review of draft-ietf-tls-ecdhe-psk-aead
Joseph Salowey <joe@salowey.net> Tue, 11 April 2017 15:22 UTC
Return-Path: <joe@salowey.net>
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 A3B1F129C4D for <tls@ietfa.amsl.com>; Tue, 11 Apr 2017 08:22:04 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.899
X-Spam-Level:
X-Spam-Status: No, score=-1.899 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=salowey-net.20150623.gappssmtp.com
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 vB-LSTNM8Ysn for <tls@ietfa.amsl.com>; Tue, 11 Apr 2017 08:22:02 -0700 (PDT)
Received: from mail-pg0-x22b.google.com (mail-pg0-x22b.google.com [IPv6:2607:f8b0:400e:c05::22b]) (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 2DBC912EAAB for <tls@ietf.org>; Tue, 11 Apr 2017 08:22:02 -0700 (PDT)
Received: by mail-pg0-x22b.google.com with SMTP id 81so170701pgh.2 for <tls@ietf.org>; Tue, 11 Apr 2017 08:22:02 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=salowey-net.20150623.gappssmtp.com; s=20150623; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=6zGLa2a1dMKbRjGqlY7/tEFjEO8oBKmnJ4xWmH0DN9A=; b=vdEojxMZTfzAKrg8MsKR71ZTWcYS63TDrSMGjce+swNVhl0F1Rr5B7BfSuoHULk3i2 0iEuHBl6SF/ggq2kuz/ac2xU2iy3cRUFqQBiR5mi57A5MakQRtgjWD/cH0Z4rMXIxJMm +bZOw0KwZCgBlN8t/O4ZkXuusI9A5pm9J/J59cTrFk+pCdbUgFH6YtzcVLrr3ejv0LB+ AhzY/OuQ+JMj6r67j7HmV9RlPQI86EHJ5uNUyZvQ6TarTAjV2+fMQ1UhCVYhpf/1CrNZ 4IyVPmkgc8QxB6txO0zIivMEFD4FGorhAqIcwGEqUcYbK9wd1l1byXz+vJmg8dAqM9sP Z12g==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=6zGLa2a1dMKbRjGqlY7/tEFjEO8oBKmnJ4xWmH0DN9A=; b=unMquTQf1zzrGft6N6H0NzZkDPZKYxnpr5whr6/DhcZPZLZ4hN4Oji6QlXNRJwXq4K 5tXd24iGBRxF+Pz5LE5FH7c0y4L3Loh8fmKKl7zss2LL8uuDDt8g/7weyqP1OrZ+bFWU umMMu4z0k6Q1TLeyy9GjO3AaP4+VjzC8tuEu5yGCGFMszYPu6rNfGIC1fyLzz6pRO4ll 08zOlYbVroD9GIcSzKGJr/pw4ZQPAKmjOsHME5Zvh54Ng+1DPOlIOPV2V6UyxcFMXuMt Y/hhpLTx4Zkfu8uzoP5e6jaSWK8RjiKB8/Nypstj+5ZhmEPxqdaetixfmQ2ZuEx4ApUW 5LyA==
X-Gm-Message-State: AFeK/H37tWLlB3vZ/1+2ENOe/rnCKIFQILWFdd55yanxQWi3DiH2PgRztTmdLUKFCrPUyHINYU/Cq5nk3EzZ9g==
X-Received: by 10.99.97.77 with SMTP id v74mr62580690pgb.76.1491924121757; Tue, 11 Apr 2017 08:22:01 -0700 (PDT)
MIME-Version: 1.0
Received: by 10.100.183.7 with HTTP; Tue, 11 Apr 2017 08:21:41 -0700 (PDT)
In-Reply-To: <CADZyTkm4YnrTFwLJcf3Zw2XxKBO0wBuyqQ0c_MqWZVjPE-zUdw@mail.gmail.com>
References: <CAOgPGoA0tTmwkcC3CPdgUd=6QNTpTxRT8pkXLD-Yezzh05b+KA@mail.gmail.com> <CADZyTkm4YnrTFwLJcf3Zw2XxKBO0wBuyqQ0c_MqWZVjPE-zUdw@mail.gmail.com>
From: Joseph Salowey <joe@salowey.net>
Date: Tue, 11 Apr 2017 08:21:41 -0700
Message-ID: <CAOgPGoCoiVjpMgyBkW7HqFgW+aEDK5PyMWC+02eTpuX8ikSBkA@mail.gmail.com>
To: Daniel Migault <daniel.migault@ericsson.com>
Cc: "tls@ietf.org" <tls@ietf.org>, draft-ietf-tls-ecdhe-psk-aead@tools.ietf.org
Content-Type: multipart/alternative; boundary="94eb2c0cc37a4f3f1b054ce5a70b"
Archived-At: <https://mailarchive.ietf.org/arch/msg/tls/liAj1MH8wrRfSj1-bjXPw1RoE9E>
Subject: Re: [TLS] Last call comments and WG Chair review of draft-ietf-tls-ecdhe-psk-aead
X-BeenThere: tls@ietf.org
X-Mailman-Version: 2.1.22
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, 11 Apr 2017 15:22:04 -0000
Hi Daniel, Please submit a revised draft with the changes below. Thanks, Joe On Tue, Mar 21, 2017 at 11:08 AM, Daniel Migault < daniel.migault@ericsson.com> wrote: > Hi, > > Thank you for the review and comments received. Given the discussion our > understanding was that the consensus was to remove CCM-256 so that suites > defined by the document apply both for TLS1.2 as well as for TLS1.3. The > draft available on github [1 > <https://github.com/mglt/draft-ietf-tls-ecdhe-psk-aead/blob/master/draft-ietf-tls-ecdhe-psk-aead>] > has been updated as follows: > > > 1. Why does TLS_ECDHE_PSK_WITH_AES_256_CCM_8_SHA256 use SHA256 instead > of SHA384 like the other 256 bit cipher suites? (From Russ Housley) > > MGLT: This was a mistake in the IANA section. The cypher suite was correct > in the remaining text. However, the current version does not consider > anymore CCM-256* which also solves this issue. > > 2. Since the security considerations mention passwords (human chosen > secrets) it should mention dictionary attacks. (From Russ Housley) > > MGLT: The issue of human chosen passwords and dictionary attacks has been > mentioned in the security consideration with the following text: > > """ > Use of Pre-Shared Keys of limited entropy may allow an active > attacker attempts to connect to the server and tries different keys. > For example, limited entropy may be provided by using short PSK in > which case an attacker may perform a brute-force attack. Other > example includes the use of a PSK chosen by a human and thus may be > exposed to dictionary attacks. > """ > > > 3. Section 2 and 3 of the document contains more detail about TLS 1.3 > than necessary. > > Section 2: This document only defines cipher suites for TLS 1.2, not TLS > 1.2 or later. A subset of equivalent cipher suites is defined in the TLS > 1.3 specification. > > MGLT: CCM-256 has been removed from the specification so that suites can > be defined for TLS 1.2 as well as TLS1.3. The following text is considered. > > """ > This document defines new cipher suites that provide Pre-Shared Key > (PSK) authentication, Perfect Forward Secrecy (PFS), and > Authenticated Encryption with Associated Data (AEAD). The cipher > suites are defined for version 1.2 of the Transport Layer Security > (TLS) [RFC5246] protocol, version 1.2 of the Datagram Transport Layer > Security (DTLS) protocol [RFC6347], as well as version 1.3 of TLS > [I-D.ietf-tls-tls13]. > """ > > Section 3 and 4: Maybe replace the last 2 paragraphs with an addition to > section 4 that states: > > "TLS 1.3 and above name, negotiate and support a subset of these cipher > suites in a different way." (TLS 1.3 does not support > TLS_ECDHE_PSK_WITH_AES_256_CCM_SHA384 and TLS_ECDHE_PSK_WITH_AES_256_ > CCM_8_SHA256) > > MGLT: As CCM-256 has been removed, we do not have to deal with the > situation where TLS1.3 only considers a subset of the suites defined for > TLS1.2. > > The following sentence in section 3 clarifies that codes points are only > defined for TLS1.2: “””The assigned code points can only be used for TLS > 1.2.”””. The description of the TLS1.3 negotiation has been limited in > section 4 to the following sentence: “””TLS 1.3 and above version, > negotiate and support these cipher suites in a different way.””” > > 4. Section 3 should contain a bit more detail about relationship to 4492 > bis and RFC 4279: > > Something like the following may be enough. > > "This messages and pre-master secret construction in this document are > based on [RFC4279]. The elliptic curve parameters used in in the > Diffie-Hellman parameters are negotiated using extensions defined in > [4492-bis]." > > MGLT: The sentence mentioned above has been added with [4492-bis] > mentioned as normative. > “”” > Messages and pre-master secret construction in this document are > based on [RFC4279]. The elliptic curve parameters used in in the > Diffie-Hellman parameters are negotiated using extensions defined in > [I-D.ietf-tls-rfc4492bis]. > “”” > > [1] https://github.com/mglt/draft-ietf-tls-ecdhe-psk-aead/blob/ > master/draft-ietf-tls-ecdhe-psk-aead > > Yours, > Daniel and John > > > On Tue, Feb 21, 2017 at 1:22 PM, Joseph Salowey <joe@salowey.net> wrote: > >> Here are the open issues for draft-ietf-tls-ecdhe-psk-aead >> >> 1. Why does TLS_ECDHE_PSK_WITH_AES_256_CCM_8_SHA256 use SHA256 instead >> of SHA384 like the other 256 bit cipher suites? (From Russ Housley) >> >> 2. Since the security considerations mention passwords (human chosen >> secrets) it should mention dictionary attacks. (From Russ Housley) >> >> 3. Section 2 and 3 of the document contains more detail about TLS 1.3 >> than necessary. >> >> Section 2: This document only defines cipher suites for TLS 1.2, not TLS >> 1.2 or later. A subset of equivalent cipher suites is defined in the TLS >> 1.3 specification. >> >> Section 3 and 4: Maybe replace the last 2 paragraphs with an addition to >> section 4 that states: >> >> "TLS 1.3 and above name, negotiate and support a subset of these cipher >> suites in a different way." (TLS 1.3 does not support >> TLS_ECDHE_PSK_WITH_AES_256_CCM_SHA384 and TLS_ECDHE_PSK_WITH_AES_256 >> _CCM_8_SHA256) >> >> 4. Section 3 should contain a bit more detail about relationship to 4492 >> bis and RFC 4279: >> >> Something like the following may be enough. >> >> "This messages and pre-master secret construction in this document are >> based on [RFC4279]. The elliptic curve parameters used in in the >> Diffie-Hellman parameters are negotiated using extensions defined in >> [4492-bis]." >> >> Thanks, >> >> Joe >> >> >> >> >> _______________________________________________ >> TLS mailing list >> TLS@ietf.org >> https://www.ietf.org/mailman/listinfo/tls >> >> >
- Re: [TLS] Last call comments and WG Chair review … Joseph Salowey
- Re: [TLS] Last call comments and WG Chair review … Daniel Migault
- [TLS] Last call comments and WG Chair review of d… Joseph Salowey
- Re: [TLS] Last call comments and WG Chair review … Martin Thomson
- Re: [TLS] Last call comments and WG Chair review … Salz, Rich
- Re: [TLS] Last call comments and WG Chair review … Yoav Nir
- Re: [TLS] Last call comments and WG Chair review … Ilari Liusvaara
- Re: [TLS] Last call comments and WG Chair review … Joseph Salowey
- Re: [TLS] Last call comments and WG Chair review … Yoav Nir
- Re: [TLS] Last call comments and WG Chair review … Salz, Rich
- Re: [TLS] Last call comments and WG Chair review … Salz, Rich
- Re: [TLS] Last call comments and WG Chair review … Joseph Salowey
- Re: [TLS] Last call comments and WG Chair review … William Whyte
- Re: [TLS] Last call comments and WG Chair review … William Whyte
- Re: [TLS] Last call comments and WG Chair review … Aaron Zauner
- Re: [TLS] Last call comments and WG Chair review … Thomas Pornin
- Re: [TLS] Last call comments and WG Chair review … Salz, Rich
- Re: [TLS] Last call comments and WG Chair review … Yoav Nir
- Re: [TLS] Last call comments and WG Chair review … Yoav Nir
- Re: [TLS] Last call comments and WG Chair review … Aaron Zauner
- Re: [TLS] Last call comments and WG Chair review … Daniel Migault
- Re: [TLS] Last call comments and WG Chair review … Joseph Salowey