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Versions: (draft-dseomn-sidr-slurm) 00 01 02 03 04 05 06 07 08 RFC 8416

SIDR                                                       D. Mandelberg
Internet-Draft                                              Unaffiliated
Intended status: Standards Track                                   D. Ma
Expires: February 14, 2017                                          ZDNS
                                                         August 13, 2016


   Simplified Local internet nUmber Resource Management with the RPKI
                        draft-ietf-sidr-slurm-02

Abstract

   The Resource Public Key Infrastructure (RPKI) is a global
   authorization infrastructure that allows the holder of Internet
   Number Resources (INRs) to make verifiable statements about those
   resources.  Network operators, e.g., Internet Service Providers
   (ISPs), can use the RPKI to validate BGP route origination
   assertions.  In the future, ISPs also will be able to use the RPKI to
   validate the path of a BGP route.  However, ISPs may want to
   establish a local view of the RPKI to control its own network while
   making use of RPKI data.  The mechanisms described in this document
   provide a simple way to enable INR holders to establish a local,
   customized view of the RPKI, overriding global RPKI repository data
   as needed.

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
   working documents as Internet-Drafts.  The list of current Internet-
   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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   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on February 14, 2017.

Copyright Notice

   Copyright (c) 2016 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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   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
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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.


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  Terminology  . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  RPKI RPs with SLURM  . . . . . . . . . . . . . . . . . . . . .  4
   3.  SLURM Mechanisms . . . . . . . . . . . . . . . . . . . . . . .  4
     3.1.  Validation Output Filtering  . . . . . . . . . . . . . . .  4
     3.2.  Locally Adding Assertions  . . . . . . . . . . . . . . . .  5
     3.3.  Combining Mechanisms . . . . . . . . . . . . . . . . . . .  5
   4.  Format of the SLURM File . . . . . . . . . . . . . . . . . . .  5
   5.  SLURM File Configuration . . . . . . . . . . . . . . . . . . .  8
     5.1.  SLURM File Atomicity . . . . . . . . . . . . . . . . . . .  8
     5.2.  Multiple SLURM Files . . . . . . . . . . . . . . . . . . .  8
   6.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . .  9
   7.  Security considerations  . . . . . . . . . . . . . . . . . . .  9
   8.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 10
   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 10
     9.1.  Informative References . . . . . . . . . . . . . . . . . . 10
     9.2.  Normative References . . . . . . . . . . . . . . . . . . . 11
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 12





















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1.  Introduction

   The Resource Public Key Infrastructure (RPKI) is a global
   authorization infrastructure that allows the holder of Internet
   Number Resources (INRs) to make verifiable statements about those
   resources.  For example, the holder of a block of IP(v4 or v6)
   addresses can issue a Route Origination Authorization (ROA) [RFC6482]
   to authorize an Autonomous System (AS) to originate routes for that
   block.  Internet Service Providers (ISPs) can then use the RPKI to
   validate BGP routes.  (Validation of the origin of a route is
   described in [RFC6483], and validation of the path of a route is
   described in [I-D.ietf-sidr-bgpsec-overview].)

   However, an RPKI relying party may want to override some of the
   information expressed via putative TAs and the certificates
   downloaded from the RPKI repository system.  For instances, [RFC6491]
   recommends the creation of ROAs that would invalidate public routes
   for reserved and unallocated address space, yet some ISPs might like
   to use BGP and the RPKI with private address space ([RFC1918],
   [RFC4193], [RFC6598]) or private AS numbers ([RFC1930], [RFC6996]).
   Local use of private address space and/or AS numbers is consistent
   with the RFCs cited above, but such use cannot be verified by the
   global RPKI.  This motivates creation of mechanisms that enable a
   network operator to publish a variant of RPKI hierarchy (for its own
   use and that of its customers) at its discretion.  Additionally, a
   network operator might wish to make use of a local override
   capability to protect routes from adverse actions [I-D.ietf-sidr-
   adverse-actions], until the results of such actions have been
   addressed.  The mechanisms developed to provide this capability to
   network operators are hereby called Simplified Local internet nUmber
   Resource Management with the RPKI (SLURM).

   SLURM allows an operator to create a local view of the global RPKI by
   generating sets of assertions.  For Origin Validation [RFC6483], an
   assertion is a tuple of {IP prefix, prefix length, maximum length, AS
   number} as used by rpki-rtr version 0 [RFC6810] and version 1
   [I-D.ietf-sidr-rpki-rtr-rfc6810-bis].  For BGPsec
   [I-D.ietf-sidr-bgpsec-overview], an assertion is a tuple of {AS
   number, subject key identifier, router public key} as used by rpki-
   rtr version.  (For the remainder of this document, these assertions
   are called Origin Validation assertions and BGPsec assertions,
   respectively.)

1.1.  Terminology

   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].



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2.  RPKI RPs with SLURM

   SLURM provides a simple way to enable INR holders to establish a
   local, customized view of the RPKI, by overriding RPKI repository
   data if needed.  To that end, an RP with SLURM filters out (removes
   from consideration for routing decisions) any assertions in the RPKI
   that are overridden by local Origin Validation assertions and BGPsec
   assertions.

   In general, the primary output of an RPKI relying party is the data
   it sends to routers over the rpki-rtr protocol.  The rpki-rtr
   protocol enables routers to query a relying party for all assertions
   it knows about (Reset Query) or for an update of only the changes in
   assertions (Serial Query).  The mechanisms specified in this document
   are to be applied to the result set for a Reset Query, and to both
   the old and new sets that are compared for a Serial Query.  Relying
   party software MAY modify other forms of output in comparable ways,
   but that is outside the scope of this document.

   +--------------+   +---------------------------+   +------------+
   |              |   |                           |   |            |
   | Repositories +--->Local cache of RPKI objects+---> Validation |
   |              |   |                           |   |            |
   +--------------+   +---------------------------+   +-----+------+
                                                            |
          +-------------------------------------------------+
          |
   +------v-------+   +---------------------------+   +------------+
   |              |   |                           |   |            |
   |    SLURM     +--->          rpki-rtr         +--->BGP Speakers|
   |              |   |                           |   |            |
   +--------------+   +---------------------------+   +------------+

           Figure 1: SLURM's Position in the Relying Party Stack


3.  SLURM Mechanisms

3.1.   Validation Output Filtering

   To prevent the global RPKI from affecting routes with locally
   reserved INRs, a relying party is locally configured with a (possibly
   empty) list of IP prefixes and/or AS numbers that are used locally.
   (In general, these IP prefixes and AS numbers will be taken from
   reserved INR spaces.)  Any Origin Validation assertions where the IP
   prefix is equal to or subsumed by a locally reserved IP prefix, are
   removed from the relying party's output.  (Note that an Origin
   Validation assertion is not removed due to its AS number matching a



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   locally reserved AS number.)  Any BGPsec assertion where the AS
   number is equal to a locally reserved AS number is removed from the
   relying party's output.

3.2.  Locally Adding Assertions

   Each relying party is locally configured with a (possibly empty) list
   of assertions.  This list is added to the relying party's output.

3.3.  Combining Mechanisms

   In the envisioned typical use case, a relying party uses both output
   filtering and locally added assertions.  In this case, the resulting
   assertions MUST be the same as if output filtering were performed
   before locally adding assertions.  I.e., locally added assertions
   MUST NOT be removed by output filtering.


4.  Format of the SLURM File

   Relying party software SHOULD support the following configuration
   format for Validation Output Filtering and Locally Adding Assertions.
   The format is defined using the Augmented Backus-Naur Form (ABNF)
   notation and core rules from [RFC5234] and the rules <IPv4address>
   and <IPv6address> from Appendix A of [RFC3986].  See Appendix A for
   an example SLURM file.

   A SLURM file, <SLURMFile>, consists of a head and a body.  The head
   identifies the file as a SLURM file, specifies the version of SLURM
   for which the file was written, and optionally contains other
   information described below.  The body contains the configuration for
   Validation Output Filtering and Locally Adding Assertions.

         SLURMFile = head body

         head = firstLine *(commentLine / headLine)

         body = *(commentLine / bodyLine)

         firstLine = %x53.4c.55.52.4d SP "1.0" EOL ; "SLURM 1.0"

         commentLine = *WSP [comment] EOL

         headLine = *WSP headCommand [ 1*WSP [comment] ] EOL







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         bodyLine = *WSP bodyCommand [ 1*WSP [comment] ] EOL

         comment = "#" *(VCHAR / WSP)

         EOL = CRLF / LF

   The head may specify a target.  If present, the target string
   identifies the environment in which the SLURM file is intended to be
   used.  The meaning of the target string, if present, is determined by
   the user.  If a target is present, a relying party SHOULD verify that
   the target is an acceptable value, and reject the SLURM file if the
   target is not acceptable.  For example, the relying party could be
   configured to accept SLURM files only if they do not specify a
   target, have a target value of "hostname=rpki.example.com", or have a
   target value of "as=65536".  If more than one target line is present,
   all targets must be acceptable to the RP.

         headCommand = target

         target =
            %x74.61.72.67.65.74 1*WSP ; "target"
            1*VCHAR

   The body contains zero or more configuration lines for Validation
   Output Filtering and Locally Adding Assertions.  Each <del> command
   specifies an INR to use for Validation Output Filtering.  Each <add>
   command specifies an assertion to use for Locally Adding Assertions.

         bodyCommand = add / del

         add =
            %x61.64.64 1*WSP ; "add"
            addItem

         del =
            %x64.65.6c 1*WSP ; "del"
            delItem

         addItem = addItemPrefixAS / addItemASKey

         ; Add a mapping from a prefix and max length to an AS number.
         addItemPrefixAS =
            %x6f.72.69.67.69.6e.61.74.69.6f.6e 1*WSP ; "origination"
            IPprefixMaxLen 1*WSP
            ASnum






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         ; Add a mapping from an AS number to a router public key.
         addItemASKey =
            %x62.67.70.73.65.63 1*WSP ; "bgpsec"
            ASnum 1*WSP
            RouterSKI 1*WSP
            RouterPubKey

         delItem = delItemPrefix / delItemAS

         ; Filter prefix-AS mappings, using the given prefix
         delItemPrefix =
            %x6f.72.69.67.69.6e.61.74.69.6f.6e 1*WSP ; "origination"
            IPprefix

         ; Filter AS-key mappings for the given AS
         delItemAS =
            %x62.67.70.73.65.63 1*WSP ; "bgpsec"
            ASnum

         IPprefix = IPv4prefix / IPv6prefix

         IPprefixMaxLen = IPv4prefixMaxLen / IPv6prefixMaxLen

         IPv4prefix = IPv4address "/" 1*2DIGIT
         IPv6prefix = IPv6address "/" 1*3DIGIT

         ; In the following two rules, if the maximum length component
         is
         ; missing, it is treated as equal to the prefix length.
         IPv4prefixMaxLen = IPv4prefix ["-" 1*2DIGIT]
         IPv6prefixMaxLen = IPv6prefix ["-" 1*3DIGIT]

         ASnum = 1*DIGIT

         ; This is the Base64 [RFC4648] encoding of a router
         certificate's
         ; Subject Key Identifer, as described in
         ; [I-D.ietf-sidr-bgpsec-pki-profiles] and [RFC6487].  This is
         the
         ; value of the ASN.1 OCTET STRING without the ASN.1 tag or
         length
         ; fields.

         RouterSKI = Base64







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         ; This is the Base64 [RFC4648] encoding of a router public
         key's
         ; subjectPublicKeyInfo value, as described in
         ; [I-D.ietf-sidr-bgpsec-algs].  This is the full ASN.1 DER
         encoding
         ; of the subjectPublicKeyInfo, including the ASN.1 tag and
         length
         ; values of the subjectPublicKeyInfo SEQUENCE.
         RouterPubKey = Base64

         Base64 = 1*(ALPHA / DIGIT / "+" / "/") 0*2"="


5.  SLURM File Configuration

5.1.  SLURM File Atomicity

   To ensure local consistency, the effect of SLURM MUST be atomic.
   That is, the output of the relying party must be either the same as
   if SLURM file were not used, or it must reflect the entire SLURM
   configuration.  For an example of why this is required, consider the
   case of two local routes for the same prefix but different origin AS
   numbers.  Both routes are configured with Locally Adding Assertions.
   If neither addition occurs, then both routes could be in the unknown
   state [RFC6483].  If both additions occur then both routes would be
   in the valid state.  However, if one addition occurs and the other
   does not, then one could be invalid while the other is valid.

5.2.  Multiple SLURM Files

   An implementation MAY support the concurrent use of multiple SLURM
   files.  In this case, the resulting inputs to Validation Output
   Filtering and Locally Adding Assertions are the respective unions of
   the inputs from each file.  The envisioned typical use case for
   multiple files is when the files have distinct scopes.  For instance,
   operators of two distinct networks may resort to one RP system to
   frame routing decisions.  As such, they probably deliver SLURM files
   to this RP respectively.  Before an RP configures SLURM files from
   different source it MUST make sure there is no internal conflict
   among the INR assertions in these SLURM files.  To do so, the RP
   SHOULD check the entries of SLURM file with regard to overlaps of the
   INR assertions and report errors to the sources that created these
   SLURM files in question.

   If a problem is detected with the INR assertions in these SLURM
   files, the RP MUST NOT use them, and SHOULD issue a warning as error
   report in the following cases:




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      1.  There may be conflicting changes to Origin Validation
          assertions if there exists an IP address X and distinct SLURM
          files Y,Z such that X is contained by any prefix in any
          <addItemPrefixAS> or <delItemPrefix> in file Y and X is
          contained by any prefix in any <addItemPrefixAS> or
          <delItemPrefix> in file Z.

      2.  There may be conflicting changes to BGPsec assertions if there
          exists an AS number X and distinct SLURM files Y,Z such that X
          is used in any <addItemASKey> or <delItemAS> in file Y and X
          is used in any <addItemASKey> or <delItemAS> in file Z.


6.  IANA Considerations

   None


7.  Security considerations

   The mechanisms described in this document provide a network operator
   with additional ways to control make use of RPKI data while
   preserving autonomy in address space and ASN management.  These
   mechanisms are applied only locally; they do not influence how other
   network operators interpret RPKI data.  Nonetheless, care should be
   taken in how these mechanisms are employed.  Note that it also is
   possible to use SLURM to (locally) manipulate assertions about non-
   private INRs, e.g., allocated address space that is globally routed.
   For example, a SLURM file may be used to override RPKI data that a
   network operator believes has been corrupted by an adverse action.
   Network operators who elect to use SLURM in this fashion should use
   extreme caution.

   The goal of the mechanisms described in this document is to enable an
   RP to create its own view of the RPKI, which is intrinsically a
   security function.  An RP using a SLURM file is trusting the
   assertions made in that file.  Errors in the SLURM file used by an RP
   can undermine the security offered by the RPKI, to that RP.  It could
   declare as invalid ROAs that would otherwise be valid, and vice
   versa.  As a result, an RP must carefully consider the security
   implications of the SLURM file being used, especially if the file is
   provided by a third party.

   Additionally, each RP using SLURM MUST ensure the authenticity and
   integrity of any SLURM file that it uses.  Initially, the SLURM file
   may be pre-configured out of band, but if the RP updates its SLURM



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   file over the network, it MUST verify the authenticity and integrity
   of the updated SLURM file.


8.  Acknowledgements

   The authors would like to thank Stephen Kent for his guidance and
   detailed reviews of this document.  Thanks go to Wei Wang for the
   idea behind the target command, to Richard Hansen for his careful
   reviews and Hui Zou for her editorial assistance.


9.  References

9.1.  Informative References

   [I-D.ietf-sidr-bgpsec-overview]
              Lepinski, M. and S. Turner, "An Overview of BGPsec",
              draft-ietf-sidr-bgpsec-overview-08 (work in progress),
              June 2016.

   [I-D.ietf-sidr-lta-use-cases]
              Bush, R., "Use Cases for Localized Versions of the RPKI",
              draft-ietf-sidr-lta-use-cases-07 (work in progress),
              July 2016.

   [I-D.ietf-sidr-rpki-rtr-rfc6810-bis]
              Bush, R. and R. Austein, "The Resource Public Key
              Infrastructure (RPKI) to Router Protocol",
              draft-ietf-sidr-rpki-rtr-rfc6810-bis-07 (work in
              progress), March 2016.

   [RFC1918]  Rekhter, Y., Moskowitz, B., Karrenberg, D., de Groot, G.,
              and E. Lear, "Address Allocation for Private Internets",
              BCP 5, RFC 1918, DOI 10.17487/RFC1918, February 1996,
              <http://www.rfc-editor.org/info/rfc1918>.

   [RFC1930]  Hawkinson, J. and T. Bates, "Guidelines for creation,
              selection, and registration of an Autonomous System (AS)",
              BCP 6, RFC 1930, DOI 10.17487/RFC1930, March 1996,
              <http://www.rfc-editor.org/info/rfc1930>.

   [RFC4193]  Hinden, R. and B. Haberman, "Unique Local IPv6 Unicast
              Addresses", RFC 4193, DOI 10.17487/RFC4193, October 2005,
              <http://www.rfc-editor.org/info/rfc4193>.

   [RFC6482]  Lepinski, M., Kent, S., and D. Kong, "A Profile for Route
              Origin Authorizations (ROAs)", RFC 6482, DOI 10.17487/



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              RFC6482, February 2012,
              <http://www.rfc-editor.org/info/rfc6482>.

   [RFC6483]  Huston, G. and G. Michaelson, "Validation of Route
              Origination Using the Resource Certificate Public Key
              Infrastructure (PKI) and Route Origin Authorizations
              (ROAs)", RFC 6483, DOI 10.17487/RFC6483, February 2012,
              <http://www.rfc-editor.org/info/rfc6483>.

   [RFC6491]  Manderson, T., Vegoda, L., and S. Kent, "Resource Public
              Key Infrastructure (RPKI) Objects Issued by IANA",
              RFC 6491, DOI 10.17487/RFC6491, February 2012,
              <http://www.rfc-editor.org/info/rfc6491>.

   [RFC6598]  Weil, J., Kuarsingh, V., Donley, C., Liljenstolpe, C., and
              M. Azinger, "IANA-Reserved IPv4 Prefix for Shared Address
              Space", BCP 153, RFC 6598, DOI 10.17487/RFC6598,
              April 2012, <http://www.rfc-editor.org/info/rfc6598>.

   [RFC6810]  Bush, R. and R. Austein, "The Resource Public Key
              Infrastructure (RPKI) to Router Protocol", RFC 6810,
              DOI 10.17487/RFC6810, January 2013,
              <http://www.rfc-editor.org/info/rfc6810>.

   [RFC6890]  Cotton, M., Vegoda, L., Bonica, R., Ed., and B. Haberman,
              "Special-Purpose IP Address Registries", BCP 153,
              RFC 6890, DOI 10.17487/RFC6890, April 2013,
              <http://www.rfc-editor.org/info/rfc6890>.

   [RFC6996]  Mitchell, J., "Autonomous System (AS) Reservation for
              Private Use", BCP 6, RFC 6996, DOI 10.17487/RFC6996,
              July 2013, <http://www.rfc-editor.org/info/rfc6996>.

   [RFC7682]  McPherson, D., Amante, S., Osterweil, E., Blunk, L., and
              D. Mitchell, "Considerations for Internet Routing
              Registries (IRRs) and Routing Policy Configuration",
              RFC 7682, DOI 10.17487/RFC7682, December 2015,
              <http://www.rfc-editor.org/info/rfc7682>.

9.2.  Normative References

   [I-D.ietf-sidr-bgpsec-algs]
              Turner, S., "BGPsec Algorithms, Key Formats, & Signature
              Formats", draft-ietf-sidr-bgpsec-algs-15 (work in
              progress), April 2016.

   [I-D.ietf-sidr-bgpsec-pki-profiles]
              Reynolds, M., Turner, S., and S. Kent, "A Profile for



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              BGPsec Router Certificates, Certificate Revocation Lists,
              and Certification Requests",
              draft-ietf-sidr-bgpsec-pki-profiles-18 (work in progress),
              July 2016.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/
              RFC2119, March 1997,
              <http://www.rfc-editor.org/info/rfc2119>.

   [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66,
              RFC 3986, DOI 10.17487/RFC3986, January 2005,
              <http://www.rfc-editor.org/info/rfc3986>.

   [RFC4648]  Josefsson, S., "The Base16, Base32, and Base64 Data
              Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,
              <http://www.rfc-editor.org/info/rfc4648>.

   [RFC5234]  Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
              Specifications: ABNF", STD 68, RFC 5234, DOI 10.17487/
              RFC5234, January 2008,
              <http://www.rfc-editor.org/info/rfc5234>.

   [RFC6487]  Huston, G., Michaelson, G., and R. Loomans, "A Profile for
              X.509 PKIX Resource Certificates", RFC 6487, DOI 10.17487/
              RFC6487, February 2012,
              <http://www.rfc-editor.org/info/rfc6487>.


Authors' Addresses

   David Mandelberg
   Unaffiliated


   Email: david@mandelberg.org


   Di Ma
   ZDNS
   4 South 4th St. Zhongguancun
   Haidian, Beijing  100190
   China

   Email: madi@zdns.cn





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