Network Working Group                                            R. Bush
Internet-Draft                                 Internet Initiative Japan
Intended status: Standards Track                          April 26, 2018
Expires: October 28, 2018


                    Origin Validation Clarifications
                    draft-ietf-sidrops-ov-clarify-02

Abstract

   Deployment of RPKI-based BGP origin validation is hampered by, among
   other things, vendor mis-implementations in two critical areas, which
   routes are validated and whether policy is applied when not specified
   by configuration.  This document is meant to clarify possible
   misunderstandings causing those mis-implementations.

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" are to
   be interpreted as described in [RFC8174] only when they appear in all
   upper case.  They may also appear in lower or mixed case as English
   words, without normative meaning.

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
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   Internet-Drafts are draft documents valid for a maximum of six months
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   This Internet-Draft will expire on October 28, 2018.

Copyright Notice

   Copyright (c) 2018 IETF Trust and the persons identified as the
   document authors.  All rights reserved.





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   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://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
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   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.

.  Introduction

   Deployment of RPKI-based BGP origin validation is hampered by, among
   other things, vendor mis-implementations in two critical areas, which
   routes are validated and whether policy is applied when not specified
   by configuration.  This document is meant to clarify possible
   misunderstandings causing those mis-implementations.

   When a route is distributed into BGP, origin validation marks the
   announcement as NotFound, Valid, or Invalid per [RFC6811].
   Operational testing has shown that the specifications of that RFC
   were not sufficient to avoid divergent implementations.  This
   document attempts to clarify two areas seeming to cause confusion.

   The implementation issues seem not to be about how to validate, i.e.,
   how to decide if a route is NotFound, Valid, or Invalid.  The issues
   seem to be which routes to mark and whether to apply policy without
   operator configuration.

.  Suggested Reading

   It is assumed that the reader understands BGP, [RFC4271], the RPKI,
   [RFC6480], Route Origin Authorizations (ROAs), [RFC6482], and RPKI-
   based Prefix Validation, [RFC6811].

.  Mark ALL Prefixes

   Significant Clarification: A router MUST mark all routes in BGP
   coming from any source (eBGP, iBGP, or redistribution from static),
   unless specifically configured otherwise by the operator.  Else the
   operator does not have the ability to drop Invalid routes coming from
   every potential source; and is therefore liable to complaints from
   neighbors about propagation of Invalid routes.  For this reason,
   [RFC6811] says

   "When a BGP speaker receives an UPDATE from a neighbor, it SHOULD
   perform a lookup as described above for each of the Routes in the
   UPDATE message.  The lookup SHOULD also be applied to routes that are



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   redistributed into BGP from another source, such as another protocol
   or a locally defined static route."

   [RFC6811] goes on to say "An implementation MAY provide configuration
   options to control which routes the lookup is applied to."

   When redistributing into BGP from connected, static, IGP, iBGP, etc.,
   there is no AS_PATH in the input to allow RPKI validation of the
   originating AS.  In such cases, the router SHOULD use the AS of the
   router's BGP configuration.  If that is ambiguous because of
   confederation, AS migration, or other multi-AS configuration, then
   the router configuration MUST provide a means of specifying the AS to
   be used on the redistribution, either per redistribution or globally.

.  Marking not Acting

   Significant Clarification: Once routes are marked, the operator
   should be in complete control of any policy applied based the
   markings.  Absent specific operator configuration, policy MUST NOT be
   applied.

   Automatic origin validation policy actions such as those described in
   [RFC8097], BGP Prefix Origin Validation State Extended Community,
   MUST NOT be carried out or otherwise applied unless specifically
   configured by the operator.

.  Security Considerations

   This document does not create security considerations beyond those of
   [RFC6811].

.  IANA Considerations

   This document has no IANA Considerations.

.  Acknowledgments

   Many thanks to John Scudder who had the patience to give constructive
   review multiple times, and to Keyur Patel who noted that the AS might
   have to be specified.  George Michaelson, Jay Borkenhagen, John
   Heasley, and Matthias Waehlisch kindly helped clean up loose wording.

.  References








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8.1.  Normative References

   [RFC6482]  Lepinski, M., Kent, S., and D. Kong, "A Profile for Route
              Origin Authorizations (ROAs)", RFC 6482,
              DOI 10.17487/RFC6482, February 2012,
              <http://www.rfc-editor.org/info/rfc6482>.

   [RFC6811]  Mohapatra, P., Scudder, J., Ward, D., Bush, R., and R.
              Austein, "BGP Prefix Origin Validation", RFC 6811,
              DOI 10.17487/RFC6811, January 2013,
              <http://www.rfc-editor.org/info/rfc6811>.

   [RFC8097]  Mohapatra, P., Patel, K., Scudder, J., Ward, D., and R.
              Bush, "BGP Prefix Origin Validation State Extended
              Community", RFC 8097, DOI 10.17487/RFC8097, March 2017,
              <http://www.rfc-editor.org/info/rfc8097>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <http://www.rfc-editor.org/info/rfc8174>.

8.2.  Informative References

   [RFC4271]  Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
              Border Gateway Protocol 4 (BGP-4)", RFC 4271,
              DOI 10.17487/RFC4271, January 2006,
              <http://www.rfc-editor.org/info/rfc4271>.

   [RFC6480]  Lepinski, M. and S. Kent, "An Infrastructure to Support
              Secure Internet Routing", RFC 6480, DOI 10.17487/RFC6480,
              February 2012, <http://www.rfc-editor.org/info/rfc6480>.

Author's Address

   Randy Bush
   Internet Initiative Japan
   5147 Crystal Springs
   Bainbridge Island, Washington  98110
   US

   Email: randy@psg.com










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