Implications of Oversized IPv6 Header Chains
RFC 7112
Document | Type |
RFC - Proposed Standard
(January 2014; No errata)
Updates RFC 2460
|
|
---|---|---|---|
Authors | Fernando Gont , Vishwas Manral , Ron Bonica | ||
Last updated | 2015-10-14 | ||
Replaces | draft-gont-6man-oversized-header-chain | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized bibtex | ||
Reviews | |||
Stream | WG state | Submitted to IESG for Publication | |
Document shepherd | Ole Trøan | ||
Shepherd write-up | Show (last changed 2013-09-27) | ||
IESG | IESG state | RFC 7112 (Proposed Standard) | |
Action Holders |
(None)
|
||
Consensus Boilerplate | Yes | ||
Telechat date | |||
Responsible AD | Brian Haberman | ||
Send notices to | (None) | ||
IANA | IANA review state | Version Changed - Review Needed | |
IANA action state | RFC-Ed-Ack |
Internet Engineering Task Force (IETF) F. Gont Request for Comments: 7112 Huawei Technologies Updates: 2460 V. Manral Category: Standards Track Ionos Networks ISSN: 2070-1721 R. Bonica Juniper Networks January 2014 Implications of Oversized IPv6 Header Chains Abstract The IPv6 specification allows IPv6 Header Chains of an arbitrary size. The specification also allows options that can, in turn, extend each of the headers. In those scenarios in which the IPv6 Header Chain or options are unusually long and packets are fragmented, or scenarios in which the fragment size is very small, the First Fragment of a packet may fail to include the entire IPv6 Header Chain. This document discusses the interoperability and security problems of such traffic, and updates RFC 2460 such that the First Fragment of a packet is required to contain the entire IPv6 Header Chain. Status of This Memo This is an Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc7112. Gont, et al. Standards Track [Page 1] RFC 7112 Implications of Oversized Header Chains January 2014 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 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 ....................................................2 2. Requirements Language ...........................................3 3. Terminology .....................................................3 4. Motivation ......................................................4 5. Updates to RFC 2460 .............................................5 6. IANA Considerations .............................................5 7. Security Considerations .........................................6 8. Acknowledgements ................................................6 9. References ......................................................7 9.1. Normative References .......................................7 9.2. Informative References .....................................7 1. Introduction With IPv6, optional internet-layer information is carried in one or more IPv6 Extension Headers [RFC2460]. Extension Headers are placed between the IPv6 header and the Upper-Layer Header in a packet. The term "Header Chain" refers collectively to the IPv6 header, Extension Headers, and Upper-Layer Header occurring in a packet. In those scenarios in which the IPv6 Header Chain is unusually long and packets are fragmented, or scenarios in which the fragment size is very small, the Header Chain may span multiple fragments. While IPv4 had a fixed maximum length for the set of all IPv4 options present in a single IPv4 packet, IPv6 does not have any equivalent maximum limit at present. This document updates the set of IPv6 specifications to create an overall limit on the size of the combination of IPv6 options and IPv6 Extension Headers that is allowed in a single IPv6 packet. Namely, it updates RFC 2460 such that the First Fragment of a fragmented datagram is required to contain the entire IPv6 Header Chain. Gont, et al. Standards Track [Page 2] RFC 7112 Implications of Oversized Header Chains January 2014 It should be noted that this requirement does not preclude the use of large payloads but, instead, merely requires that all headers, starting from the IPv6 base header and continuing up to the Upper- Layer Header (e.g., TCP or the like) be present in the FirstShow full document text