[Docs] [txt|pdf] [Tracker] [Email] [Diff1] [Diff2] [Nits]

Versions: (RFC 7983) 00 01 draft-ietf-avtcore-rfc7983bis

AVTCORE Working Group                                           B. Aboba
INTERNET-DRAFT                                     Microsoft Corporation
Updates: 7983, 5764                                         G. Salgueiro
Category: Standards Track                                  Cisco Systems
Expires: May 19, 2021                                         C. Perkins
                                                   University of Glasgow
                                                        19 November 2020

                  Multiplexing Scheme Updates for QUIC
                 draft-aboba-avtcore-rfc7983bis-01.txt

Abstract

   This document defines how QUIC, Datagram Transport Layer Security
   (DTLS), Real-time Transport Protocol (RTP), RTP Control Protocol
   (RTCP), Session Traversal Utilities for NAT (STUN), Traversal Using
   Relays around NAT (TURN), and ZRTP packets are multiplexed on a
   single receiving socket.

   This document updates RFC 7983 and RFC 5764.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on May 19, 2021.














Aboba, et. al                Standards Track                    [Page 1]


INTERNET-DRAFT    Multiplexing Scheme Updates for QUIC  19 November 2020


Copyright Notice

   Copyright (c) 2020 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Multiplexing of TURN Channels . . . . . . . . . . . . . . . .   3
   3.  Updates to RFC 7983 . . . . . . . . . . . . . . . . . . . . .   4
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .   5
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   6
   6. References . . . . . . . . . . . . . . . . . . . . . . . . . .   6
     6.1.  Normative References  . . . . . . . . . . . . . . . . . .   6
     6.2.  Informative References  . . . . . . . . . . . . . . . . .   7
   Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .   7
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   8























Aboba, et. al                Standards Track                    [Page 2]


INTERNET-DRAFT    Multiplexing Scheme Updates for QUIC  19 November 2020


1.  Introduction

   "Multiplexing Scheme Updates for Secure Real-time Transport Protocol
   (SRTP) Extension for Datagram Transport Layer Security (DTLS)"
   [RFC7983] defines a scheme for a Real-time Transport Protocol (RTP)
   [RFC3550] receiver to demultiplex DTLS [RFC6347], Session Traversal
   Utilities for NAT (STUN) [RFC5389], Secure Real-time Transport
   Protocol (SRTP) / Secure Real-time Transport Control Protocol (SRTCP)
   [RFC3711], ZRTP [RFC6189] and TURN Channel packets arriving on a
   single port.

   This document updates [RFC7983] and [RFC5764] to also allow QUIC [I-
   D.ietf-quic-transport] to be multiplexed on the same port.  For peer-
   to-peer operation in WebRTC scenarios as described in [WEBRTC-
   QUIC][WEBRTC-QUIC-TRIAL], RTP is used to transport audio and video
   and QUIC is used for data exchange, SRTP [RFC3711] is keyed using
   DTLS-SRTP [RFC5764] and therefore SRTP/SRTCP [RFC3550], STUN, TURN,
   DTLS [RFC6347] and QUIC need to be multiplexed on the same port.

   Since new versions of QUIC are allowed to change aspects of the wire
   image, there is no guarantee that future versions of QUIC beyond
   version 1 will adhere to the multiplexing scheme described in this
   document.

1.1.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

2.  Multiplexing of TURN Channels

   TURN channels are an optimization where data packets are exchanged
   with a 4-byte prefix instead of the standard 36-byte STUN overhead
   (see Section 2.5 of [RFC5766]).  [RFC7983] allocated the values from
   64 to 79 in order to allow TURN channels to be demultiplexed when the
   TURN Client does the channel binding request in combination with the
   demultiplexing scheme described in [RFC7983].

   As noted in [I-D.aboba-avtcore-quic-multiplexing], the first octet of
   a QUIC short header packet falls in the range 64 to 127, thereby
   overlapping with the allocated range for TURN channels of 64 to 79.

   The first octet of QUIC long header packets fall in the range 192 to
   255.  Since QUIC long header packets preceed QUIC short header
   packets, if no packets with a first octet in the range of 192 to 255
   have been received, a packet whose first octet is in the range of 64
   to 79 can be demultplexed unambiguously as TURN Channel traffic.



Aboba, et. al                Standards Track                    [Page 3]


INTERNET-DRAFT    Multiplexing Scheme Updates for QUIC  19 November 2020


   Since WebRTC implementations supporting QUIC data exchange do not
   utilize TURN Channels, once packets with a first octet in the range
   of 192 to 255 have been received, a packet whose first octet is in
   the range of 64 to 127 can be demultiplexed as QUIC traffic.

3.  Updates to RFC 7983

   This document updates the text in Section 7 of [RFC7983] (which in
   turn updates [RFC5764]) as follows:

   OLD TEXT

   The process for demultiplexing a packet is as follows.  The receiver
   looks at the first byte of the packet.  If the value of this byte is
   in between 0 and 3 (inclusive), then the packet is STUN.  If the
   value is between 16 and 19 (inclusive), then the packet is ZRTP.  If
   the value is between 20 and 63 (inclusive), then the packet is DTLS.
   If the value is between 64 and 79 (inclusive), then the packet is
   TURN Channel.  If the value is in between 128 and 191 (inclusive),
   then the packet is RTP (or RTCP, if both RTCP and RTP are being
   multiplexed over the same destination port).  If the value does not
   match any known range, then the packet MUST be dropped and an alert
   MAY be logged.  This process is summarized in Figure 3.

                    +----------------+
                    |        [0..3] -+--> forward to STUN
                    |                |
                    |      [16..19] -+--> forward to ZRTP
                    |                |
        packet -->  |      [20..63] -+--> forward to DTLS
                    |                |
                    |      [64..79] -+--> forward to TURN Channel
                    |                |
                    |    [128..191] -+--> forward to RTP/RTCP
                    +----------------+

     Figure 3: The DTLS-SRTP receiver's packet demultiplexing algorithm.

   END OLD TEXT

   NEW TEXT

   The process for demultiplexing a packet is as follows.  The receiver
   looks at the first byte of the packet.  If the value of this byte is
   in between 0 and 3 (inclusive), then the packet is STUN.  If the
   value is between 16 and 19 (inclusive), then the packet is ZRTP.  If
   the value is between 20 and 63 (inclusive), then the packet is DTLS.
   If the value is in between 128 and 191 (inclusive) then the packet is



Aboba, et. al                Standards Track                    [Page 4]


INTERNET-DRAFT    Multiplexing Scheme Updates for QUIC  19 November 2020


   RTP (or RTCP, if both RTCP and RTP are being multiplexed over the
   same destination port). If the value is between 80 and 127 or between
   192 and 255 (inclusive) then the packet is QUIC. If the value is
   between 64 and 79 inclusive, then if a packet has been previously
   forwarded that is in the range of 192 and 255, then the packet is
   QUIC, otherwise it is TURN Channel.

   If the value does not match any known range, then the packet MUST be
   dropped and an alert MAY be logged. This process is summarized in
   Figure 3.

                       +----------------+
                       |        [0..3] -+--> forward to STUN
                       |                |
                       |      [16..19] -+--> forward to ZRTP
                       |                |
           packet -->  |      [20..63] -+--> forward to DTLS
                       |                |
                       |      [64..79] -+--> forward to TURN Channel
                       |     [64..127] -+--> forward to QUIC
                       |                |    (Short Header)
                       |    [128..191] -+--> forward to RTP/RTCP
                       |                |
                       |    [192..255] -+--> forward to QUIC
                       +----------------+    (Long Header)

        Figure 3: The receiver's packet demultiplexing algorithm.

   END NEW TEXT

4.  Security Considerations

   The solution discussed in this document could potentially introduce
   some additional security considerations beyond those detailed in
   [RFC7983].

   Due to the additional logic required, if mis-implemented, heuristics
   have the potential to mis-classify packets.

   When QUIC is used for only for data exchange, the TLS-within-QUIC
   exchange [I-D.ietf-quic-tls] derives keys used solely to protect the
   QUIC data packets.  If properly implemented, this should not affect
   the transport of SRTP nor the derivation of SRTP keys via DTLS-SRTP,
   but if badly implemented, both transport and key derivation could be
   adversely impacted.






Aboba, et. al                Standards Track                    [Page 5]


INTERNET-DRAFT    Multiplexing Scheme Updates for QUIC  19 November 2020


5.  IANA Considerations

   This document does not require actions by IANA.

6.  References

6.1.  Normative References

[I-D.ietf-quic-tls]
             Thomson, M. and S. Turner, "Using Transport Layer Security
             (TLS) to Secure QUIC", draft-ietf-quic-tls-32 (work in
             progress), October 20, 2020.

[I-D.ietf-quic-transport]
             Iyengar, J. and M. Thomson, "QUIC: A UDP-Based Multiplexed
             and Secure Transport", draft-ietf-quic-transport-32 (work
             in progress), October 20, 2020.

[RFC2119]    Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, DOI
             10.17487/RFC2119, March 1997, <http://www.rfc-
             editor.org/info/rfc2119>.

[RFC3550]    Schulzrinne, H., Casner, S., Frederick, R., and V.
             Jacobson, "RTP: A Transport Protocol for Real-Time
             Applications", STD 64, RFC 3550, DOI 10.17487/RFC3550, July
             2003, <http://www.rfc-editor.org/info/rfc3550>.

[RFC3711]    Baugher, M., McGrew, D., Naslund, M., Carrara, E., and K.
             Norrman, "The Secure Real-time Transport Protocol (SRTP)",
             RFC 3711, DOI 10.17487/RFC3711, March 2004,
             <http://www.rfc-editor.org/info/rfc3711>.

[RFC5389]    Rosenberg, J., Mahy, R., Matthews, P., and D. Wing,
             "Session Traversal Utilities for NAT (STUN)", RFC 5389, DOI
             10.17487/RFC5389, October 2008, <http://www.rfc-
             editor.org/info/rfc5389>.

[RFC5764]    McGrew, D. and E. Rescorla, "Datagram Transport Layer
             Security (DTLS) Extension to Establish Keys for the Secure
             Real-time Transport Protocol (SRTP)", RFC 5764, DOI
             10.17487/RFC5764, May 2010, <http://www.rfc-
             editor.org/info/rfc5764>.

[RFC5766]    Mahy, R., Matthews, P., and J. Rosenberg, "Traversal Using
             Relays around NAT (TURN): Relay Extensions to Session
             Traversal Utilities for NAT (STUN)", RFC 5766, DOI
             10.17487/RFC5766, April 2010, <http://www.rfc-



Aboba, et. al                Standards Track                    [Page 6]


INTERNET-DRAFT    Multiplexing Scheme Updates for QUIC  19 November 2020


             editor.org/info/rfc5766>.

[RFC7983]    Petit-Huguenin, M. and G. Salgueiro, "Multiplexing Scheme
             Updates for Secure Real-time Transport Protocol (SRTP)
             Extension for Datagram Transport Layer Security (DTLS)",
             RFC 7983, DOI 10.17487/RFC7983, September 2016,
             <https://www.rfc-editor.org/info/rfc7983>.

6.2.  Informative References

[I-D.aboba-avtcore-quic-multiplexing]
             Aboba, B., Thatcher, P. and C. Perkins, "QUIC
             Multiplexing", draft-aboba-avtcore-quic-multiplexing-04
             (work in progress), January 28, 2020.

[RFC6189]    Zimmermann, P., Johnston, A., Ed., and J. Callas, "ZRTP:
             Media Path Key Agreement for Unicast Secure RTP", RFC 6189,
             DOI 10.17487/RFC6189, April 2011, <http://www.rfc-
             editor.org/info/rfc6189>.

[RFC6347]    Rescorla, E. and N. Modadugu, "Datagram Transport Layer
             Security Version 1.2", RFC 6347, DOI 10.17487/RFC6347,
             January 2012, <http://www.rfc-editor.org/info/rfc6347>.

[WEBRTC-QUIC]
             Thatcher, P. and B. Aboba, "QUIC API For Peer-to-Peer
             Connections", W3C Community Group Draft (work in progress),
             January 2020, <https://w3c.github.io/webrtc-quic>

[WEBRTC-QUIC-TRIAL]
             Hampson, S., "RTCQuicTransport Coming to an Origin Trial
             Near You (Chrome 73)", January 2019,
             <https://developers.google.com/web/updates/
             2019/01/rtcquictransport-api>

Acknowledgments

   We would like to thank Martin Thomson, Roni Even and other
   participants in the IETF QUIC and AVTCORE working groups for their
   discussion of the QUIC multiplexing issue, and their input relating
   to potential solutions.










Aboba, et. al                Standards Track                    [Page 7]


INTERNET-DRAFT    Multiplexing Scheme Updates for QUIC  19 November 2020


Authors' Addresses

   Bernard Aboba
   Microsoft Corporation
   One Microsoft Way
   Redmond, WA  98052
   USA

   Email:  bernard.aboba@gmail.com

   Gonzalo Salgueiro
   Cisco Systems
   7200-12 Kit Creek Road
   Research Triangle Park, NC  27709
   United States of America

   Email: gsalguei@cisco.com

   Colin Perkins
   School of Computing Science
   University of Glasgow
   Glasgow  G12 8QQ
   United Kingdom

   Email: csp@csperkins.org


























Aboba, et. al                Standards Track                    [Page 8]


Html markup produced by rfcmarkup 1.129d, available from https://tools.ietf.org/tools/rfcmarkup/