Network Working Group J. Abley, Ed. Internet-Draft Afilias Updates: 2460 (if approved) May 6, 2007 Intended status: Standards Track Expires: November 7, 2007 Deprecation of Type 0 Routing Headers in IPv6 draft-jabley-ipv6-rh0-is-evil-00 Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. 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. 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/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on November 7, 2007. Copyright Notice Copyright (C) The IETF Trust (2007). Abley Expires November 7, 2007 [Page 1] Internet-Draft Deprecation of RH0 May 2007 Abstract The functionality provided by IPv6's Type 0 Routing Header can be exploited in order to perform remote network discovery, to bypass firewalls and to achieve packet amplification for the purposes of generating denial-of-service traffic. This document updates the IPv6 specification to deprecate the use of IPv6 Type 0 Routing Headers, in the light of these security concerns. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . 4 3. Implementation . . . . . . . . . . . . . . . . . . . . . . . . 5 4. Operations . . . . . . . . . . . . . . . . . . . . . . . . . . 6 5. Security Considerations . . . . . . . . . . . . . . . . . . . 7 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 7. Acknowlegements . . . . . . . . . . . . . . . . . . . . . . . 9 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 10 8.1. Normative References . . . . . . . . . . . . . . . . . . . 10 8.2. Informative References . . . . . . . . . . . . . . . . . . 10 Appendix A. Change History . . . . . . . . . . . . . . . . . . . 11 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 12 Intellectual Property and Copyright Statements . . . . . . . . . . 13 Abley Expires November 7, 2007 [Page 2] Internet-Draft Deprecation of RH0 May 2007 1. Introduction [RFC2460] defines an IPv6 extension header called "Routing Header", identified by a Next Header value of 43 in the immediately preceding header. A particular Routing Header subtype denoted as "Type 0" is also defined. Type 0 Routing Headers are referred to as "RH0" in this document. Use of RH0 has been shown to have unpleasant security implications. This document deprecates the use of RH0. Abley Expires November 7, 2007 [Page 3] Internet-Draft Deprecation of RH0 May 2007 2. Definitions RH0 in this document denotes the IPv6 Extension Header type 43 ("Routing Header") variant 0 ("Type 0 Routing Header"), as defined in [RFC2460]. 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]. Abley Expires November 7, 2007 [Page 4] Internet-Draft Deprecation of RH0 May 2007 3. Implementation Compliant IPv6 hosts and routers MUST NOT transmit IPv6 datagrams containing RH0. Abley Expires November 7, 2007 [Page 5] Internet-Draft Deprecation of RH0 May 2007 4. Operations Compliant IPv6 hosts and routers which receive IPv6 datagrams containing RH0 MUST silently discard those datagrams without further processing. Abley Expires November 7, 2007 [Page 6] Internet-Draft Deprecation of RH0 May 2007 5. Security Considerations The purpose of this document is to deprecate a feature of IPv6 which has been shown to have serious security implications. Specific examples of vulnerabilities which are facilitated by the availability of RH0 can be found in [BiondiEbalard]. Abley Expires November 7, 2007 [Page 7] Internet-Draft Deprecation of RH0 May 2007 6. IANA Considerations This document requests that IANA update the description of variant 0 of IPv6 header-type 43 ("Routing Header") to indicate that the use of RH0 is deprecated. Abley Expires November 7, 2007 [Page 8] Internet-Draft Deprecation of RH0 May 2007 7. Acknowlegements An eloquent and useful description of the operational security implications of RH0 was presented by Philippe Biondi and Arnaud Ebalard at the CanSecWest conference in Vancouver, 2007 [BiondiEbalard]. This presentation resulted in widespread publicity for the risks associated with RH0, and that in turn led to much discussion in the IETF. Abley Expires November 7, 2007 [Page 9] Internet-Draft Deprecation of RH0 May 2007 8. References 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. 8.2. Informative References [BiondiEbalard] BIONDI, P. and A. EBALARD, "IPv6 Routing Header Security", April 2007. Abley Expires November 7, 2007 [Page 10] Internet-Draft Deprecation of RH0 May 2007 Appendix A. Change History This section to be removed prior to publication. 00 Strawman, circulated to provoke discussion. Abley Expires November 7, 2007 [Page 11] Internet-Draft Deprecation of RH0 May 2007 Author's Address Joe Abley (editor) Afilias Canada Corp. Suite 204, 4141 Yonge Street Toronto, ON M2P 2A8 Canada Phone: +1 416 673 4176 Email: jabley@ca.afilias.info Abley Expires November 7, 2007 [Page 12] Internet-Draft Deprecation of RH0 May 2007 Full Copyright Statement Copyright (C) The IETF Trust (2007). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. 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Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org. Acknowledgment Funding for the RFC Editor function is provided by the IETF Administrative Support Activity (IASA). Abley Expires November 7, 2007 [Page 13]