Internet Draft RJ Atkinson
draft-irtf-rrg-ilnp-icmpv6-05.txt Consultant
Category: Experimental SN Bhatti
Expires: 29 NOV 2012 U. St Andrews
29 May 2012
ICMP Locator Update message for ILNPv6
draft-irtf-rrg-ilnp-icmpv6-05.txt
Status of this Memo
Distribution of this memo is unlimited.
Copyright (c) 2012 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.
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
This document may contain material from IETF Documents or
IETF Contributions published or made publicly available
before November 10, 2008. The person(s) controlling the
copyright in some of this material may not have granted the IETF
Trust the right to allow modifications of such material outside
the IETF Standards Process. Without obtaining an adequate
license from the person(s) controlling the copyright in such
materials, this document may not be modified outside the IETF
Standards Process, and derivative works of it may not be created
outside the IETF Standards Process, except to format it for
publication as an RFC or to translate it into languages other
than English. This document may not be modified, and derivative
works of it may not be created, except to publish it as an RFC or
to translate it into languages other than English.
Internet-Drafts are working documents of the Internet
Engineering Task Force (IETF), its areas, and its working
groups. Note that other groups may also distribute working
documents as Internet-Drafts.
Atkinson & Bhatti Expires in 6 months [Page 1]
Internet Draft ILNPv6 ICMP 29 MAY 2012
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."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/1id-abstracts.html
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html
This document is not on the IETF standards-track and does not
specify any level of standard. This document merely provides
information for the Internet community.
This document is part of the ILNP document set, which has had
extensive review within the IRTF Routing Research Group. ILNP
is one of the recommendations made by the RG Chairs. Separately,
various refereed research papers on ILNP have also been published
during this decade. So the ideas contained herein have had much
broader review than the IRTF Routing RG. The views in this
document were considered controversial by the Routing RG,
but the RG reached a consensus that the document still should be
published. The Routing RG has had remarkably little consensus
on anything, so virtually all Routing RG outputs are considered
controversial.
Abstract
This note specifies an experimental ICMPv6 message type used with
the Identifier-Locator Network Protocol (ILNP). The
Identifier-Locator Network Protocol (ILNP) is an experimental,
evolutionary enhancement to IP. This message is used to
dynamically update Identifier/Locator bindings for an existing
ILNP session. This is a product of the IRTF Routing RG.
Table of Contents
1. Introduction ...........................................3
1.1 ILNP Document Roadmap.................................3
1.2 ICMPv6 Locator Update.................................3
1.3 Terminology...........................................3
2. Syntax..................................................4
2.1 Example ICMPv6 Locator Update message.................5
3. Transport Protocol Effects..............................6
4. Implementation Considerations...........................6
Atkinson & Bhatti Expires in 6 months [Page 2]
Internet Draft ILNPv6 ICMP 29 MAY 2012
5. Backwards Compatibility.................................7
6. Security Considerations ................................7
7. IANA Considerations ....................................8
8. References .............................................8
1. Introduction
At present, the research and development community are examining
various alternatives for evolving the Internet Architecture. Several
different classes of evolution are being considered. One class is
often called "Map and Encapsulate", where traffic would be mapped and
then tunnelled through the inter-domain core of the Internet.
Another class being considered is sometimes known as
"Identifier/Locator Split". This document relates to a proposal that
is in the latter class of evolutionary approaches.
1.1 ILNP Document Roadmap
The ILNP Architecture document [ILNP-ARCH] is the best place to start
reading about ILNP. ILNP has multiple possible instantiations.
[ILNP-ENG] discusses engineering and implementation aspects common to
all instances of ILNP. A new IPv6 Destination Option used with
ILNPv6 is defined in [ILNP-NONCEv6]. This document discusses a new
ICMP for IPv6 message. [ILNP-DNS] describes new Domain Name System
(DNS) resource records used with ILNP. Other documents describe ILNP
for IPv4 (ILNPv4).
1.2 ICMPv6 Locator Update
As described in [ILNP-ARCH] and [ILNP-ENG], an ILNP for IPv6 (ILNPv6)
node might need to inform correspondent ILNPv6 nodes of changes to
the set of valid Locator values. The new ICMPv6 Locator Update
message described in this document enables an ILNP-capable node to
update its correspondents about the currently valid set of Locators
valid to use in reaching the node sending this message.[RFC2460]
[RFC4443]
This new ICMPv6 message MUST ONLY be used for ILNPv6 sessions.
Authentication is always required, as described in the Security
Considerations section later in this note.
Some might consider any and all use of ICMP to be undesirable. In
that context, please note that while this specification uses ICMP, on
grounds that this is a control message, there is no architectural
difference between using ICMP and using some different framing, for
example UDP.
1.3 Terminology
Atkinson & Bhatti Expires in 6 months [Page 3]
Internet Draft ILNPv6 ICMP 29 MAY 2012
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].
2. Syntax
The ICMP for IPv6 message described in this section has ICMP Type XXX
and is used ONLY with a current ILNPv6 session. This message enables
an ILNPv6 node to inform ILNPv6 correspondent nodes of changes to the
active Locator set for the ILNPv6 node that originates this message.
This particular ICMP for IPv6 message MUST ONLY be used with ILNPv6
communications sessions.
The ICMP for IPv6 message described in this section has ICMP Type XXX
and is used ONLY with a current ILNPv4 session. This message enables
an ILNPv6 node to advertise changes to the active Locator set for the
ILNPv6 node that originates this message to its unicast ILNP
correspondent nodes. It also enables those correspondents to
acknowledge receipt of the advertisement.
This particular ICMP for IPv6 message MUST ONLY be used with ILNPv6
communications sessions. The Checksum field for this message is
calculated identically as for any other IPv6 ICMP message.
ICMPv6 Locator Update message
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Num of Locs | Operation | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
/ Locator [1] /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Preference [1] | Lifetime [1] |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
/ Locator [2] /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Preference [2] | Lifetime [2] |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| . |
| . |
| . |
ICMPv6 Locator Update fields:
Atkinson & Bhatti Expires in 6 months [Page 4]
Internet Draft ILNPv6 ICMP 29 MAY 2012
Type XXX
Code 0
Checksum The 16-bit one's complement of the one's
complement sum of the ICMP message,
starting with the ICMP Type. For
computing the checksum, the Checksum
field is set to 0.
Num of Locs The number of 64-bit Locator values
that are advertised in this message.
This field MUST NOT be zero.
Locator[i], The 64-bit Locator values currently
i = 1..Num of Locs valid for the sending ILNPv6 node.
Preference[i], The preferability of each Locator[i],
i = 1..Num of Locs relative to other valid Locator[i]
values. The Preference numbers here are
identical, both in syntax and semantics,
to the Preference values for L64 records
as specified by [ILNP-DNS].
Lifetime[i] The maximum number of seconds that this
i = 1..Num of Locs particular Locator may be considered
valid. Normally, this is identical
to the DNS lifetime of the
corresponding L64 record, if one
exists.
Operation The value in this field indicates
whether this is a Locator Update
Advertisement (0x01) or a Locator
Update Acknowledgement (0x02).
RESERVED A field reserved for possible future
use. At present, the sender MUST
initialise this field to zero.
Receivers should ignore this field at
present. The field might be used for
some protocol function in future.
The Operation field has value 1 (hexadecimal 0x01) for a Locator
Update Advertisement. The Operation field has value 2 (hexadecimal
0x02) for a Locator Update Acknowledgement. All other values of the
Operation field are reserved for future use by future revisions of
Atkinson & Bhatti Expires in 6 months [Page 5]
Internet Draft ILNPv6 ICMP 29 MAY 2012
this specification.
A node whose set of valid Locators has changed MUST send Locator
Update Advertisement messages to each correspondent node for each
active unicast ILNP session. For unicast ILNP sessions, the receiver
of a valid (e.g. authentication checks all passed, advertisement is
received from a current correspondent node) Locator Update
Advertisement addressed to the receiver MUST send a Locator Update
Acknowledgement back to the sender of the Locator Update
Advertisement. The Acknowledgement message body is identical to the
received Advertisement message body, except for the Operation value.
All ILNPv6 ICMP Locator Update messages MUST contain a valid ILNPv6
Identifier option and MUST contain an ILNPv6 Nonce Option.
ILNPv6 ICMP Locator Update messages also MAY be protected using IP
Security for ILNP [ILNP-ENG] [RFC4301]. Deployments in high-threat
environments SHOULD also protect ILNPv6 ICMP Locator Update messages
using IP Security. While IPsec ESP can protect a payload, no form of
IPsec ESP is able to protect an IPv6 option that appears prior to the
ESP header.
Note that even when IP Security for ILNP is in use, the ILNP Nonce
Option still MUST be present. This simplifies protocol processing,
and it also means that a receiver can perform the inexpensive check
of the Nonce value before performing any (potentially expensive)
cryptographic calculation.
2.1 Example ICMPv6 Locator Update message
This example shows the ICMPv6 syntax for the case where 2 Locator values
are being indicated.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Num of Locs | RESERVED | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
/ Locator [1] /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Preference [1] | Lifetime [1] |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
/ Locator [2] /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Preference [2] | Lifetime [2] |
Atkinson & Bhatti Expires in 6 months [Page 6]
Internet Draft ILNPv6 ICMP 29 MAY 2012
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
3. Transport Protocol Effects
This message has no impact on any transport protocol.
The message may affect where packets for a given transport
session are sent, but an ILNP design objective is to decouple
transport-protocols from network-layer changes.
4. Implementation Considerations
Implementers may use any internal implementation they wish,
provided that the external appearance is the same as this
implementation approach.
To support ILNPv6, and to retain the incremental deployability
and backwards compatibility needed, the network layer needs a
mode bit in the Transport Control Block (or its equivalent) to
track which IP sessions are using the classic IPv6 mode and which
IP sessions are using the Identifier/Locator Split mode.
Further, when supporting ILNPv4, nodes will need to support a
Identifier Locator Communication Cache (ILCC) in the network
layer as described in [ILNP-ENG].
A node sending an ICMP Locator Update message MUST include all
currently valid Locator values in that message. A node receiving
a valid ICMP Locator Update message MUST replace the previously
current set of Locator values for that correspondent node in its
own ILCC with the newly received set of Locator values.
Every implementation needs to support a large number of Locator
values being sent or received in a single ICMP Locator Update
message, because a multi-homed node or multi-homed site might
have a large number of upstream links to different service
providers, each with its own Locator value.
5. Backwards Compatibility
This IPv6 ICMP message uses the same checksum calculations as any
other IPv6 ICMP message.
When ILNPv6 is not in use, the receiving IPv6 mode MUST discard
the ICMP Locator Update packet without processing the packet.
Atkinson & Bhatti Expires in 6 months [Page 7]
Internet Draft ILNPv6 ICMP 29 MAY 2012
This is standard behaviour for a non-ILNPv6 node when receiving
an ICMPv6 message with an unknown header field value.
6. Security Considerations
Security considerations for the overall ILNP Architecture
are described in [ILNP-ARCH]. Additional common security
considerations are described in [ILNP-ENG]. This section
describes security considerations specific to ILNPv6 topics
discussed in this document.
The ICMPv6 Locator Update message MUST ONLY be used for ILNPv6
sessions.
The ILNP Nonce Destination Option [ILNP-NONCEv6] MUST be present
in packets containing an ICMPv6 Locator Update message. Further,
the received Nonce Destination Option MUST contain the correct
nonce value for the packet to be accepted by the recipient and
then passed to the ICMPv6 protocol for processing. If either of
these requirements are not met, the received packet MUST be
discarded as a forgery, and a security event SHOULD be logged
by the system receiving the non-authentic packet.
Sessions operating in higher risk environments SHOULD use IP
Security for ILNP [ILNP-ENG] [RFC4301] *in addition* to the
ILNPv6 Nonce Destination Option. Use of IP Security for ILNP to
protect a packet does NOT permit the packet to be sent without
the Nonce Destination Option.
Implementations need to support the case where a single ICMP
Locator Update message contains a large number of Locator and
Preference values and ought not develop a security fault
(e.g. stack overflow) due to a received message containing more
Locator values than expected.
If the ILNP Nonce value is predictable, then an off-path attacker
might be able to forge data or control packets. This risk also
is mitigated by the existing common practice of IP Source Address
filtering [RFC2827] [RFC3704].
7. IANA Considerations
Subjecto to IESG Approval, consistent with the procedures of
[RFC4443], IANA is requested to assign a value, replacing the
XXX, to the ICMP Type listed in Section 2.
There are no other IANA actions for this document.
Atkinson & Bhatti Expires in 6 months [Page 8]
Internet Draft ILNPv6 ICMP 29 MAY 2012
8. References
This document contains both normative and informative references.
8.1. Normative References
[ILNP-ARCH] R.J. Atkinson & S.N. Bhatti, "ILNP Architecture",
draft-irtf-rrg-ilnp-arch, May 2012.
[ILNP-DNS] R.J. Atkinson & S.N. Bhatti, "DNS Resource Records
for ILNP", draft-irtf-rrg-ilnp-dns, May 2012.
[ILNP-ENG] R.J. Atkinson & S.N. Bhatti, "ILNP Engineering
Considerations", draft-irtf-rrg-ilnp-eng,
May 2012.
[ILNP-NONCEv6] R.J. Atkinson & S.N. Bhatti, "Nonce Destination
Option", draft-irtf-rrg-ilnp-noncev6,
May 2012.
[RFC2119] Bradner, S., "Key words for use in RFCs to
Indicate Requirement Levels", BCP 14, RFC 2119,
March 1997.
[RFC2460] S. Deering & R. Hinden, "Internet Protocol
Version 6 Specification", RFC 2460,
December 1998.
[RFC3704] F. Baker, P. Savola, "Ingress Filtering for
Multihomed Networks", RFC 3704, March 2004.
[RFC4301] S. Kent & K. Seo, "Security Architecture for
the Internet Protocol", RFC 4301, December 2005.
[RFC4443] A. Conta, S. Deering, and M. Gupta (Ed.),
"Internet Control Message Protocol (ICMPv6)
for the Internet Protocol Version 6 (IPv6)
Specification", RFC 4443, March 2006.
8.2. Informative References
[RFC2827] P. Ferguson and D. Senie, "Network Ingress
Filtering: Defeating Denial of Service Attacks
which employ IP Source Address Spoofing",
RFC 2827, May 2000.
ACKNOWLEDGEMENTS
Atkinson & Bhatti Expires in 6 months [Page 9]
Internet Draft ILNPv6 ICMP 29 MAY 2012
Steve Blake, Stephane Bortzmeyer, Mohamed Boucadair, Noel
Chiappa, Wes George, Steve Hailes, Joel Halpern, Mark Handley,
Volker Hilt, Paul Jakma, Dae-Young Kim, Tony Li, Yakov Rehkter,
Bruce Simpson, Robin Whittle and John Wroclawski (in alphabetical
order) provided review and feedback on earlier versions of this
document. Steve Blake provided an especially thorough review of
an early version of the entire ILNP document set, which was
extremely helpful. We also wish to thank the anonymous reviewers
of the various ILNP papers for their feedback.
Roy Arends provided expert guidance on technical and procedural
aspects of DNS issues.
RFC EDITOR NOTE
This section is to be removed prior to publication.
Please note that this document is written in British English, so
British English spelling is used throughout. This is consistent
with existing practice in several other RFCs, for example
RFC-5887.
This document tries to be very careful with history, in the
interest of correctly crediting ideas to their earliest
identifiable author(s). So in several places the first published
RFC about a topic is cited rather than the most recent published
RFC about that topic.
Author's Address
RJ Atkinson
Consultant
San Jose, CA
95125 USA
Email: rja.lists@gmail.com
SN Bhatti
School of Computer Science
University of St Andrews
North Haugh, St Andrews,
Fife, Scotland, UK
KY16 9SX
Email: saleem@cs.st-andrews.ac.uk
Expires: 29 NOV 2012
Atkinson & Bhatti Expires in 6 months [Page 10]
Internet Draft ILNPv6 ICMP 29 MAY 2012
Atkinson & Bhatti Expires in 6 months [Page 11]