IPv6 maintenance Working Group (6man)                            F. Gont
Internet-Draft                                    SI6 Networks / UTN-FRH
Updates: 2464, 2467, 2470, 4291  2491, 2492,                        A. Cooper
         2497, 2590, 3146, 3572, 4291,                             Cisco
         4338, 4391, 5072, 5121 (if                            D. Thaler
         approved)                                                      Cisco                                             Microsoft
Intended status: Standards Track                               D. Thaler
Expires: July 28, 2014                                         Microsoft                                  W. Liu
Expires: April 11, 2015                              Huawei Technologies
                                                        January 24,
                                                         October 8, 2014

          Recommendation on Stable IPv6 Interface Identifiers
                    draft-ietf-6man-default-iids-00
                    draft-ietf-6man-default-iids-01

Abstract

   Stateless Address Autoconfiguration (SLAAC) for

   The IPv6 typically
   results in hosts configuring one or more stable addresses composed of
   a network prefix advertised by a local router, and an addressing architecture defines Modified EUI-64 format
   Interface
   Identifier that typically embeds a hardware Identifiers, and the existing IPv6 over various link-layers
   specify how such identifiers are derived from the underlying link-
   layer address (e.g., an IEEE LAN MAC address). address) when employing IPv6
   Stateless Address Autoconfiguration (SLAAC).  The security and
   privacy implications of embedding hardware addresses in the Interface
   Identifier have been known and understood for some time now, and some
   popular IPv6 implementations have already deviated from such schemes
   to mitigate these issues.  This document recommends [I-D.ietf-6man-stable-privacy-addresses] as changes the recommended
   default Interface Identifier generation scheme for the generating stable IPv6 addresses to that specified in
   RFC7217, and recommends against embedding hardware addresses in IPv6
   Interface Identifiers.  It formally updates RFC2464, RFC2467,
   RFC2470, RFC2491, RFC2492, RFC2497, RFC2590, RFC3146, RFC3572,
   RFC4291, RFC4338, RFC4391, RFC5072, and RFC5121, wihch require IPv6
   Interface Identifiers to be derived from the underlying link-layer
   address.

Status of this 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
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   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
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   material or to cite them other than as "work in progress."
   This Internet-Draft will expire on July 28, 2014. April 11, 2015.

Copyright Notice

   Copyright (c) 2014 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
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   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . .  3   2
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .  4   3
   3.  Generation of IPv6 Interface Identifiers  . . . . . . . . . . .  5   3
   4.  Future Work . . . . . . . . . . . . . . . . . . . . . . . . .   4
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  6
   5.   4
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  7
   6.   4
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . .  8
   7.   4
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . . .  9
     7.1.   5
     8.1.  Normative References  . . . . . . . . . . . . . . . . . . .  9
     7.2.   5
     8.2.  Informative References  . . . . . . . . . . . . . . . . . .  9   6
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . . . 10   7

1.  Introduction

   [RFC4862] specifies Stateless Address Autoconfiguration (SLAAC) for
   IPv6 [RFC2460], which typically results in hosts configuring one or
   more "stable" addresses composed of a network prefix advertised by a
   local router, and an Interface Identifier (IID) [RFC4291] that
   typically embeds a hardware address (e.g., an IEEE LAN MAC address).

   The security and privacy implications of embedding a hardware address
   in an IPv6 Interface ID have been known for some time now, and are
   discussed in great detail in
   [I-D.ietf-6man-ipv6-address-generation-privacy]; they include:

   o  Network activity correlation

   o  Location tracking
   o  Address scanning

   o  Device-specific vulnerability exploitation

   Some popular IPv6 implementations have already deviated from the
   traditional stable IID generation scheme to mitigate the
   aforementioned security and privacy implications [Microsoft].

   As a result of the aforementioned issues, this document recommends
   the implementation of an alternative scheme
   ([I-D.ietf-6man-stable-privacy-addresses]) ([RFC7217]) as the
   default stable Interface-ID generation scheme, such that the
   aforementioned issues are mitigated.

   NOTE: [RFC4291] defines the "Modified EUI-64 format" for Interface
   identifiers.  Appendix A of [RFC4291] then describes how to transform
   an IEEE EUI-64 identifier, or an IEEE 802 48-bit MAC address from
   which an EUI-64 identifier is derived, into an interface identifier
   in the Modified EUI-64 format.

2.  Terminology

   Stable address:
      An address that does not vary over time within the same network
      (as defined in [I-D.ietf-6man-ipv6-address-generation-privacy].

   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 RFC 2119 [RFC2119].

3.  Generation of IPv6 Interface Identifiers

   Nodes SHOULD NOT employ IPv6 address generation schemes that embed
   the underlying hardware address in the Interface Identifier.  Namely,
   nodes SHOULD NOT generate Interface Identifiers with the schemes
   specified in [RFC2464], [RFC2467], [RFC2470], [RFC2491], [RFC2492],
   [RFC2497], [RFC2590], [RFC3146], [RFC3572], [RFC4338], [RFC4391],
   [RFC5121], and [RFC2470]. [RFC5072].

   Nodes SHOULD implement and employ
   [I-D.ietf-6man-stable-privacy-addresses] [RFC7217] as the default scheme for
   generating stable IPv6 addresses with SLAAC.

   Future specifications SHOULD NOT specify IPv6 address generation
   schemes that embed the underlying hardware address in the Interface
   Identifier.

4.  Future Work

   At the time of this writing, the mechanisms specified in the
   following documents are not compatible with the recommendations in
   this document:

   o  RFC 6282 [RFC6282]

   o  RFC 4944 [RFC4944]

   o  RFC 6755 [RFC6775]

   It is expected that that future revisions or updates of these
   documents will address the aforementioned issues such that the
   requirements in this documents can be enforced.

5.  IANA Considerations

   There are no IANA registries within this document.  The RFC-Editor
   can remove this section before publication of this document as an
   RFC.

5.

6.  Security Considerations

   This document recommends [I-D.ietf-6man-stable-privacy-addresses] [RFC7217] as the default scheme for
   generating IPv6 stable addresses with SLAAC, such that the security
   and privacy issues of Interface IDs that embed hardware addresses are
   mitigated.

6.

7.  Acknowledgements

   The authors would like to thank Erik Nordmark and Ray Hunter for
   providing a detailed review of this document.

   The authors would like to thank (in alphabetical order) Fred Baker,
   Scott Brim, Brian Carpenter, Samita Chakrabarti, Tim Chown, Lorenzo
   Colitti, Jean-Michel Combes, Greg Daley, Esko Dijk, Ralph Droms,
   David Farmer, Brian Haberman, Ulrich Herberg, Bob Hinden, Jahangir
   Hossain, Jonathan Hui, Ray Hunter, Sheng Jiang, Roger Jorgensen, Dan
   Luedtke, George Mitchel, Erik Nordmark, Simon Perreault, Tom Petch,
   Alexandru Petrescu, Michael Richardson, Arturo Servin, Mark Smith,
   Tom Taylor, Ole Troan, and Tina Tsou, and Randy Turner, for providing
   valuable comments on earlier versions of this document.

   Fernando Gont would like to thank Ray Hunter for providing valuable
   input on this topic.

7.

8.  References

7.1.

8.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2460]  Deering, S. and R. Hinden, "Internet Protocol, Version 6
              (IPv6) Specification", RFC 2460, December 1998.

   [RFC2464]  Crawford, M., "Transmission of IPv6 Packets over Ethernet
              Networks", RFC 2464, December 1998.

   [RFC2467]  Crawford, M., "Transmission of IPv6 Packets over FDDI
              Networks", RFC 2467, December 1998.

   [RFC2470]  Crawford, M., Narten, T., and S. Thomas, "Transmission of
              IPv6 Packets over Token Ring Networks", RFC 2470, December
              1998.

   [RFC2492]  Armitage, G., Schulter, P., and M. Jork, "IPv6 over ATM
              Networks", RFC 2492, January 1999.

   [RFC4291]  Hinden, R. and S. Deering, "IP Version 6 Addressing
              Architecture", RFC 4291, February 2006.

   [RFC4862]  Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
              Address Autoconfiguration", RFC 4862, September 2007.

   [I-D.ietf-6man-stable-privacy-addresses]

   [RFC7217]  Gont, F., "A Method for Generating Semantically Opaque
              Interface Identifiers with IPv6 Stateless Address
              Autoconfiguration (SLAAC)",
              draft-ietf-6man-stable-privacy-addresses-16 (work in
              progress), December 2013.

7.2. RFC 7217, April 2014.

   [RFC2491]  Armitage, G., Schulter, P., Jork, M., and G. Harter, "IPv6
              over Non-Broadcast Multiple Access (NBMA) networks", RFC
              2491, January 1999.

   [RFC2497]  Souvatzis, I., "Transmission of IPv6 Packets over ARCnet
              Networks", RFC 2497, January 1999.

   [RFC2590]  Conta, A., Malis, A., and M. Mueller, "Transmission of
              IPv6 Packets over Frame Relay Networks Specification", RFC
              2590, May 1999.

   [RFC3146]  Fujisawa, K. and A. Onoe, "Transmission of IPv6 Packets
              over IEEE 1394 Networks", RFC 3146, October 2001.

   [RFC3572]  Ogura, T., Maruyama, M., and T. Yoshida, "Internet
              Protocol Version 6 over MAPOS (Multiple Access Protocol
              Over SONET/SDH)", RFC 3572, July 2003.

   [RFC4338]  DeSanti, C., Carlson, C., and R. Nixon, "Transmission of
              IPv6, IPv4, and Address Resolution Protocol (ARP) Packets
              over Fibre Channel", RFC 4338, January 2006.

   [RFC4391]  Chu, J. and V. Kashyap, "Transmission of IP over
              InfiniBand (IPoIB)", RFC 4391, April 2006.

   [RFC5121]  Patil, B., Xia, F., Sarikaya, B., Choi, JH., and S.
              Madanapalli, "Transmission of IPv6 via the IPv6
              Convergence Sublayer over IEEE 802.16 Networks", RFC 5121,
              February 2008.

   [RFC5072]  Varada, S., Haskins, D., and E. Allen, "IP Version 6 over
              PPP", RFC 5072, September 2007.

   [RFC6282]  Hui, J. and P. Thubert, "Compression Format for IPv6
              Datagrams over IEEE 802.15.4-Based Networks", RFC 6282,
              September 2011.

   [RFC4944]  Montenegro, G., Kushalnagar, N., Hui, J., and D. Culler,
              "Transmission of IPv6 Packets over IEEE 802.15.4
              Networks", RFC 4944, September 2007.

   [RFC6775]  Shelby, Z., Chakrabarti, S., Nordmark, E., and C. Bormann,
              "Neighbor Discovery Optimization for IPv6 over Low-Power
              Wireless Personal Area Networks (6LoWPANs)", RFC 6775,
              November 2012.

8.2.  Informative References

   [I-D.ietf-6man-ipv6-address-generation-privacy]
              Cooper, A., Gont, F., and D. Thaler, "Privacy
              Considerations for IPv6 Address Generation Mechanisms",
              draft-ietf-6man-ipv6-address-generation-privacy-00
              draft-ietf-6man-ipv6-address-generation-privacy-01 (work
              in progress), October 2013. February 2014.

   [Microsoft]
              Davies, J., "Understanding IPv6, 3rd. ed", page 83,
              Microsoft Press, 2012, <http://it-ebooks.info/book/1022/>.

Authors' Addresses

   Fernando Gont
   SI6 Networks / UTN-FRH
   Evaristo Carriego 2644
   Haedo, Provincia de Buenos Aires  1706
   Argentina

   Phone: +54 11 4650 8472
   Email: fgont@si6networks.com
   URI:   http://www.si6networks.com

   Alissa Cooper
   Cisco
   707 Tasman Drive
   Milpitas, CA  95035
   US

   Phone: +1-408-902-3950
   Email: alcoop@cisco.com
   URI:   https://www.cisco.com/

   Dave Thaler
   Microsoft
   Microsoft Corporation
   One Microsoft Way
   Redmond, WA  98052

   Phone: +1 425 703 8835
   Email: dthaler@microsoft.com

   Will Liu
   Huawei Technologies
   Bantian, Longgang District
   Shenzhen  518129
   P.R. China

   Email: liushucheng@huawei.com