Return-Path: 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 8EF771A890A for ; Mon, 17 Aug 2015 09:20:39 -0700 (PDT) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -2.6 X-Spam-Level: X-Spam-Status: No, score=-2.6 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_LOW=-0.7, 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 5qMNQEQGmf7f for ; Mon, 17 Aug 2015 09:20:37 -0700 (PDT) Received: from 9.mo69.mail-out.ovh.net (9.mo69.mail-out.ovh.net [46.105.56.78]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 5F2451A891B for ; Mon, 17 Aug 2015 09:20:33 -0700 (PDT) Received: from mail190.ha.ovh.net (b9.ovh.net [213.186.33.59]) by mo69.mail-out.ovh.net (Postfix) with SMTP id C9DAA1020C82 for ; Mon, 17 Aug 2015 18:20:31 +0200 (CEST) Received: from localhost (HELO queueout) (127.0.0.1) by localhost with SMTP; 17 Aug 2015 18:20:31 +0200 Received: from 130.163-14-84.ripe.coltfrance.com (HELO ?10.41.51.97?) (contact@simonbernard.eu@84.14.163.130) by ns0.ovh.net with SMTP; 17 Aug 2015 18:20:29 +0200 Message-ID: <55D209CC.4080708@simonbernard.eu> Date: Mon, 17 Aug 2015 18:20:28 +0200 From: Simon Bernard User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.7.0 MIME-Version: 1.0 To: Eric Rescorla References: <55BB88FD.4060901@simonbernard.eu> <55BBA7DA.8000806@simonbernard.eu> <55D1EDC5.1010106@simonbernard.eu> In-Reply-To: Content-Type: multipart/alternative; boundary="------------050203000102030301080000" X-Ovh-Tracer-Id: 706220717259241714 X-Ovh-Remote: 84.14.163.130 (130.163-14-84.ripe.coltfrance.com) X-Ovh-Local: 213.186.33.20 (ns0.ovh.net) X-OVH-SPAMSTATE: OK X-OVH-SPAMSCORE: 0 X-OVH-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrfeekfedrgedvucetufdoteggucfrrhhofhhilhgvmecuqfggjfenuceurghilhhouhhtmecufedttdenuc X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: 0 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrfeekfedrgedvucetufdoteggucfrrhhofhhilhgvmecuqfggjfenuceurghilhhouhhtmecufedttdenuc Archived-At: Cc: "tls@ietf.org" Subject: Re: [TLS] DTLS epoch and resume session/handshake 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." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 17 Aug 2015 16:20:39 -0000 This is a multi-part message in MIME format. --------------050203000102030301080000 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 8bit I re-readed this paragraph and it's still not clear, what did you mean by connection at transport layer for UDP. I well understand that if a server receive a clientHello with epoch=0, this means that a new handshake should be done. But I still don't know what happends in a ResumeHandshake use case. In fact, my use case is a client behind a NAT which communicate periodically. at each period, its IP/Port could changed (because of NAT), so we would like to resume handshake each time. 1) Does it make sense ? 2) If yes, should we do the resume handhsake with epoch = 0 or continue with previous epoch ? Le 17/08/2015 16:24, Eric Rescorla a écrit : > Please see RFC 6347 S 4.2.8 > > -Ekr > > > On Mon, Aug 17, 2015 at 7:20 AM, Simon Bernard > > wrote: > > I'm sorry to insist, but What did you mean by transport level > connection ? For me UDP was a connectionless protocol. > > Simon > > > Le 31/07/2015 18:53, Eric Rescorla a écrit : >> >> >> On Fri, Jul 31, 2015 at 6:52 PM, Simon Bernard >> > wrote: >> >> Thx. >> What did you mean by connection ? >> >> >> transport level connection. >> >> A resume handshake is a new connection ? >> >> >> You can also resume when you renegotiate. >> >> -Ekr >> >> >> Le 31/07/2015 16:54, Eric Rescorla a écrit : >> >> The epoch is set to 0 at the start of each connection and >> then incremented >> with each handshake on that connection. >> >> -Ekr >> >> On Fri, Jul 31, 2015 at 4:41 PM, Simon Bernard >> >> > >> wrote: >> >> Hi, >> >> I search in DTLS RFC 6347 if the epoch should be >> (re)set to 0 >> when we start a resume handshake, or if we keep the >> last used >> value, or the last used value+1 ? I can not any clue >> of that in >> the spec. >> Any idea ? >> >> Thx >> Simon >> >> _______________________________________________ >> TLS mailing list >> TLS@ietf.org > > >> https://www.ietf.org/mailman/listinfo/tls >> >> >> >> > > --------------050203000102030301080000 Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: 8bit I re-readed this paragraph and it's still not clear, what did you mean by connection at transport layer for UDP.

I well understand that if a server receive a clientHello with epoch=0, this means that a new handshake should be done.

But I still don't know what happends in a ResumeHandshake use case.

In fact, my use case is a client behind a NAT which communicate periodically. at each period, its IP/Port could changed (because of NAT), so we would like to resume handshake each time.
1) Does it make sense ?
2) If yes, should we do the resume handhsake with epoch = 0 or continue with previous epoch ?


Le 17/08/2015 16:24, Eric Rescorla a écrit :
Please see RFC 6347 S 4.2.8

-Ekr


On Mon, Aug 17, 2015 at 7:20 AM, Simon Bernard <contact@simonbernard.eu> wrote:
I'm sorry to insist, but What did you mean by transport level connection ? For me UDP was a connectionless protocol.

Simon


Le 31/07/2015 18:53, Eric Rescorla a écrit :


On Fri, Jul 31, 2015 at 6:52 PM, Simon Bernard <contact@simonbernard.eu> wrote:
Thx.
What did you mean by connection ?

transport level connection.

 
A resume handshake is a new connection ?

You can also resume when you renegotiate.

-Ekr


Le 31/07/2015 16:54, Eric Rescorla a écrit :
The epoch is set to 0 at the start of each connection and then incremented
with each handshake on that connection.

-Ekr

 On Fri, Jul 31, 2015 at 4:41 PM, Simon Bernard <contact@simonbernard.eu <mailto:contact@simonbernard.eu>> wrote:

    Hi,

      I search in DTLS RFC 6347 if the epoch should be (re)set to 0
    when we start a resume handshake, or if we keep the last used
    value, or the last used value+1 ? I can not any clue of that in
    the spec.
      Any idea ?

    Thx
    Simon

    _______________________________________________
    TLS mailing list
     TLS@ietf.org <mailto:TLS@ietf.org>
    https://www.ietf.org/mailman/listinfo/tls







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