Internet Engineering Task Force (IETF)                         G. Huston
Request for Comments: 6487                                 G. Michaelson
Category: Standards Track                                     R. Loomans
ISSN: 2070-1721                                                    APNIC
                                                           February 2012


             A Profile for X.509 PKIX Resource Certificates

Abstract

   This document defines a standard profile for X.509 certificates for
   the purpose of supporting validation of assertions of "right-of-use"
   of Internet Number Resources (INRs).  The certificates issued under
   this profile are used to convey the issuer's authorization of the
   subject to be regarded as the current holder of a "right-of-use" of
   the INRs that are described in the certificate.  This document
   contains the normative specification of Certificate and Certificate
   Revocation List (CRL) syntax in the Resource Public Key
   Infrastructure (RPKI).  This document also specifies profiles for the
   format of certificate requests and specifies the Relying Party RPKI
   certificate path validation procedure.

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/rfc6487.















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Copyright Notice

   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.





































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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  4
     1.1.  Terminology  . . . . . . . . . . . . . . . . . . . . . . .  5
   2.  Describing Resources in Certificates . . . . . . . . . . . . .  5
   3.  End-Entity (EE) Certificates and Signing Functions in the RPKI  5
   4.  Resource Certificates  . . . . . . . . . . . . . . . . . . . .  6
     4.1.  Version  . . . . . . . . . . . . . . . . . . . . . . . . .  6
     4.2.  Serial Number  . . . . . . . . . . . . . . . . . . . . . .  6
     4.3.  Signature Algorithm  . . . . . . . . . . . . . . . . . . .  6
     4.4.  Issuer . . . . . . . . . . . . . . . . . . . . . . . . . .  7
     4.5.  Subject  . . . . . . . . . . . . . . . . . . . . . . . . .  7
     4.6.  Validity . . . . . . . . . . . . . . . . . . . . . . . . .  7
       4.6.1.  notBefore  . . . . . . . . . . . . . . . . . . . . . .  8
       4.6.2.  notAfter . . . . . . . . . . . . . . . . . . . . . . .  8
     4.7.  Subject Public Key Info  . . . . . . . . . . . . . . . . .  8
     4.8.  Resource Certificate Extensions  . . . . . . . . . . . . .  8
       4.8.1.  Basic Constraints  . . . . . . . . . . . . . . . . . .  8
       4.8.2.  Subject Key Identifier . . . . . . . . . . . . . . . .  9
       4.8.3.  Authority Key Identifier . . . . . . . . . . . . . . .  9
       4.8.4.  Key Usage  . . . . . . . . . . . . . . . . . . . . . .  9
       4.8.5.  Extended Key Usage . . . . . . . . . . . . . . . . . .  9
       4.8.6.  CRL Distribution Points  . . . . . . . . . . . . . . . 10
       4.8.7.  Authority Information Access . . . . . . . . . . . . . 10
       4.8.8.  Subject Information Access . . . . . . . . . . . . . . 11
       4.8.9.  Certificate Policies . . . . . . . . . . . . . . . . . 12
       4.8.10. IP Resources . . . . . . . . . . . . . . . . . . . . . 12
       4.8.11. AS Resources . . . . . . . . . . . . . . . . . . . . . 12
   5.  Resource Certificate Revocation Lists  . . . . . . . . . . . . 13
   6.  Resource Certificate Requests  . . . . . . . . . . . . . . . . 13
     6.1.  PCKS#10 Profile  . . . . . . . . . . . . . . . . . . . . . 14
       6.1.1.  PKCS#10 Resource Certificate Request Template Fields . 14
     6.2.  CRMF Profile . . . . . . . . . . . . . . . . . . . . . . . 15
       6.2.1.  CRMF Resource Certificate Request Template Fields  . . 15
       6.2.2.  Resource Certificate Request Control Fields  . . . . . 16
     6.3.  Certificate Extension Attributes in Certificate Requests . 16
   7.  Resource Certificate Validation  . . . . . . . . . . . . . . . 17
     7.1.  Resource Extension Validation  . . . . . . . . . . . . . . 17
     7.2.  Resource Certification Path Validation . . . . . . . . . . 18
   8.  Design Notes . . . . . . . . . . . . . . . . . . . . . . . . . 19
   9.  Operational Considerations for Profile Agility . . . . . . . . 22
   10. Security Considerations  . . . . . . . . . . . . . . . . . . . 24
   11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 25
   12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 25
     12.1. Normative References . . . . . . . . . . . . . . . . . . . 25
     12.2. Informative References . . . . . . . . . . . . . . . . . . 26
   Appendix A.  Example Resource Certificate  . . . . . . . . . . . . 27
   Appendix B.  Example Certificate Revocation List . . . . . . . . . 31



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1.  Introduction

   This document defines a standard profile for X.509 certificates
   [X.509] for use in the context of certification of Internet Number
   Resources (INRs), i.e., IP Addresses and Autonomous System (AS)
   numbers.  Such certificates are termed "resource certificates".  A
   resource certificate is a certificate that conforms to the PKIX
   profile [RFC5280], and that conforms to the constraints specified in
   this profile.  A resource certificate attests that the issuer has
   granted the subject a "right-of-use" for a listed set of IP addresses
   and/or Autonomous System numbers.

   This document is referenced by Section 7 of the "Certificate Policy
   (CP) for the Resource Public Key Infrastructure (RPKI)" [RFC6484].
   It is an integral part of that policy and the normative specification
   for certificate and Certificate Revocation List (CRL) syntax used in
   the RPKI.  The document also specifies profiles for the format of
   certificate requests, and the relying party (RP) RPKI certificate
   path validation procedure.

   Resource certificates are to be used in a manner that is consistent
   with the RPKI Certificate Policy (CP) [RFC6484].  They are issued by
   entities that assign and/or allocate public INRs, and thus the RPKI
   is aligned with the public INR distribution function.  When an INR is
   allocated or assigned by a number registry to an entity, this
   allocation can be described by an associated resource certificate.
   This certificate is issued by the number registry, and it binds the
   certificate subject's key to the INRs enumerated in the certificate.
   One or two critical extensions, the IP Address Delegation or AS
   Identifier Delegation Extensions [RFC3779], enumerate the INRs that
   were allocated or assigned by the issuer to the subject.

   Relying party (RP) validation of a resource certificate is performed
   in the manner specified in Section 7.1.  This validation procedure
   differs from that described in Section 6 of [RFC5280], such that:

   o  additional validation processing imposed by the INR extensions is
      required,

   o  a confirmation of a public key match between the CRL issuer and
      the resource certificate issuer is required, and

   o  the resource certificate is required to conform to this profile.

   This profile defines those fields that are used in a resource
   certificate that MUST be present for the certificate to be valid.
   Any extensions not explicitly mentioned MUST be absent.  The same
   applies to the CRLs used in the RPKI, that are also profiled in this



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   document.  A Certification Authority (CA) conforming to the RPKI CP
   MUST issue certificates and CRLs consistent with this profile.

1.1.  Terminology

   It is assumed that the reader is familiar with the terms and concepts
   described in "Internet X.509 Public Key Infrastructure Certificate
   and Certificate Revocation List (CRL) Profile" [RFC5280], and "X.509
   Extensions for IP Addresses and AS Identifiers" [RFC3779].

   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].

2.  Describing Resources in Certificates

   The framework for describing an association between the subject of a
   certificate and the INRs currently under the subject's control is
   described in [RFC3779].  This profile further requires that:

   o  Every resource certificate MUST contain either the IP Address
      Delegation or the Autonomous System Identifier Delegation
      extension, or both.

   o  These extensions MUST be marked as critical.

   o  The sorted canonical format describing INRs, with maximal spanning
      ranges and maximal spanning prefix masks, as defined in [RFC3779],
      MUST be used for the resource extension field, except where the
      "inherit" construct is used instead.

   When validating a resource certificate, an RP MUST verify that the
   INRs described in the issuer's resource certificate encompass the
   INRs of the resource certificate being validated.  In this context,
   "encompass" allows for the issuer's INRs to be the same as, or a
   strict superset of, the subject's INRs.

3.  End-Entity (EE) Certificates and Signing Functions in the RPKI

   As noted in [RFC6480], the primary function of end-entity (EE)
   certificates in the RPKI is the verification of signed objects that
   relate to the usage of the INRs described in the certificate, e.g.,
   Route Origin Authorizations (ROAs) and manifests.

   The private key associated with an EE certificate is used to sign a
   single RPKI signed object, i.e., the EE certificate is used to
   validate only one object.  The EE certificate is embedded in the
   object as part of a Cryptographic Message Syntax (CMS) signed-data



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   structure [RFC6488].  Because of the one-to-one relationship between
   the EE certificate and the signed object, revocation of the
   certificate effectively revokes the corresponding signed object.

   An EE certificate may be used to validate a sequence of signed
   objects, where each signed object in the sequence overwrites the
   previous instance of the signed object in the repository publication
   point, such that only one instance of the signed object is published
   at any point in time (e.g., an EE certificate MAY be used to sign a
   sequence of manifests [RFC6486]).  Such EE certificates are termed
   "sequential use" EE certificates.

   EE certificates used to validate only one instance of a signed
   object, and are not used thereafter or in any other validation
   context, are termed "one-time-use" EE certificates.

4.  Resource Certificates

   A resource certificate is a valid X.509 public key certificate,
   consistent with the PKIX profile [RFC5280], containing the fields
   listed in this section.  Only the differences from [RFC5280] are
   noted below.

   Unless specifically noted as being OPTIONAL, all the fields listed
   here MUST be present, and any other fields MUST NOT appear in a
   conforming resource certificate.  Where a field value is specified
   here, this value MUST be used in conforming resource certificates.

4.1.  Version

   As resource certificates are X.509 version 3 certificates, the
   version MUST be 3 (i.e., the value of this field is 2).

   RPs need not process version 1 or version 2 certificates (in contrast
   to [RFC5280]).

4.2.  Serial Number

   The serial number value is a positive integer that is unique for each
   certificate issued by a given CA.

4.3.  Signature Algorithm

   The algorithm used in this profile is specified in [RFC6485].







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4.4.  Issuer

   The value of this field is a valid X.501 distinguished name.

   An issuer name MUST contain one instance of the CommonName attribute
   and MAY contain one instance of the serialNumber attribute.  If both
   attributes are present, it is RECOMMENDED that they appear as a set.
   The CommonName attribute MUST be encoded using the ASN.1 type
   PrintableString [X.680].  Issuer names are not intended to be
   descriptive of the identity of issuer.

   The RPKI does not rely on issuer names being globally unique, for
   reasons of security.  However, it is RECOMMENDED that issuer names be
   generated in a fashion that minimizes the likelihood of collisions.
   See Section 8 for (non-normative) suggested name-generation
   mechanisms that fulfill this recommendation.

4.5.  Subject

   The value of this field is a valid X.501 distinguished name
   [RFC4514], and is subject to the same constraints as the issuer name.

   In the RPKI, the subject name is determined by the issuer, not
   proposed by the subject [RFC6481].  Each distinct subordinate CA and
   EE certified by the issuer MUST be identified using a subject name
   that is unique per issuer.  In this context, "distinct" is defined as
   an entity and a given public key.  An issuer SHOULD use a different
   subject name if the subject's key pair has changed (i.e., when the CA
   issues a certificate as part of re-keying the subject.)  Subject
   names are not intended to be descriptive of the identity of subject.

4.6.  Validity

   The certificate validity period is represented as a SEQUENCE of two
   dates: the date on which the certificate validity period begins
   (notBefore) and the date on which the certificate validity period
   ends (notAfter).

   While a CA is typically advised against issuing a certificate with a
   validity period that spans a greater period of time than the validity
   period of the CA's certificate that will be used to validate the
   issued certificate, in the context of this profile, a CA MAY have
   valid grounds to issue a subordinate certificate with a validity
   period that exceeds the validity period of the CA's certificate.







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4.6.1.  notBefore

   The "notBefore" time SHOULD be no earlier than the time of
   certificate generation.

   In the RPKI, it is valid for a certificate to have a value for this
   field that pre-dates the same field value in any superior
   certificate.  Relying Parties SHOULD NOT attempt to infer from this
   time information that a certificate was valid at a time in the past,
   or that it will be valid at a time in the future, as the scope of an
   RP's test of validity of a certificate refers specifically to
   validity at the current time.

4.6.2.  notAfter

   The "notAfter" time represents the anticipated lifetime of the
   current resource allocation or assignment arrangement between the
   issuer and the subject.

   It is valid for a certificate to have a value for this field that
   post-dates the same field value in any superior certificate.  The
   same caveats apply to RP's assumptions relating to the certificate's
   validity at any time other than the current time.

4.7.  Subject Public Key Info

   The algorithm used in this profile is specified in [RFC6485].

4.8.  Resource Certificate Extensions

   The following X.509 v3 extensions MUST be present in a conforming
   resource certificate, except where explicitly noted otherwise.  Each
   extension in a resource certificate is designated as either critical
   or non-critical.  A certificate-using system MUST reject the
   certificate if it encounters a critical extension it does not
   recognize; however, a non-critical extension MAY be ignored if it is
   not recognized [RFC5280].

4.8.1.  Basic Constraints

   The Basic Constraints extension field is a critical extension in the
   resource certificate profile, and MUST be present when the subject is
   a CA, and MUST NOT be present otherwise.

   The issuer determines whether the "cA" boolean is set.

   The Path Length Constraint is not specified for RPKI certificates,
   and MUST NOT be present.



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4.8.2.  Subject Key Identifier

   This extension MUST appear in all resource certificates.  This
   extension is non-critical.

   The Key Identifier used for resource certificates is the 160-bit
   SHA-1 hash of the value of the DER-encoded ASN.1 bit string of the
   Subject Public Key, as described in Section 4.2.1.2 of [RFC5280].

4.8.3.  Authority Key Identifier

   This extension MUST appear in all resource certificates, with the
   exception of a CA who issues a "self-signed" certificate.  In a self-
   signed certificate, a CA MAY include this extension, and set it equal
   to the Subject Key Identifier.  The authorityCertIssuer and
   authorityCertSerialNumber fields MUST NOT be present.  This extension
   is non-critical.

   The Key Identifier used for resource certificates is the 160-bit
   SHA-1 hash of the value of the DER-encoded ASN.1 bit string of the
   issuer's public key, as described in Section 4.2.1.1 of [RFC5280].

4.8.4.  Key Usage

   This extension is a critical extension and MUST be present.

   In certificates issued to certification authorities only, the
   keyCertSign and CRLSign bits are set to TRUE, and these MUST be the
   only bits set to TRUE.

   In EE certificates, the digitalSignature bit MUST be set to TRUE and
   MUST be the only bit set to TRUE.

4.8.5.  Extended Key Usage

   The Extended Key Usage (EKU) extension MUST NOT appear in any CA
   certificate in the RPKI.  This extension also MUST NOT appear in EE
   certificates used to verify RPKI objects (e.g., ROAs or manifests.
   The extension MUST NOT be marked critical.

   The EKU extension MAY appear in EE certificates issued to routers or
   other devices.  Permitted values for the EKU OIDs will be specified
   in Standards Track RFCs issued by other IETF working groups that
   adopt the RPKI profile and that identify application-specific
   requirements that motivate the use of such EKUs.






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4.8.6.  CRL Distribution Points

   This extension MUST be present, except in "self-signed" certificates,
   and it is non-critical.  In a self-signed certificate, this extension
   MUST be omitted.

   In this profile, the scope of the CRL is specified to be all
   certificates issued by this CA issuer.

   The CRL Distribution Points (CRLDP) extension identifies the
   location(s) of the CRL(s) associated with certificates issued by this
   issuer.  The RPKI uses the URI [RFC3986] form of object
   identification.  The preferred URI access mechanism is a single rsync
   URI ("rsync://") [RFC5781] that references a single inclusive CRL for
   each issuer.

   In this profile, the certificate issuer is also the CRL issuer,
   implying that the CRLIssuer field MUST be omitted, and the
   distributionPoint field MUST be present.  The Reasons field MUST be
   omitted.

   The distributionPoint MUST contain the fullName field, and MUST NOT
   contain a nameRelativeToCRLIssuer.  The form of the generalName MUST
   be of type URI.

   The sequence of distributionPoint values MUST contain only a single
   DistributionPoint.  The DistributionPoint MAY contain more than one
   URI value.  An rsync URI [RFC5781] MUST be present in the
   DistributionPoint and MUST reference the most recent instance of this
   issuer's CRL.  Other access form URIs MAY be used in addition to the
   rsync URI, representing alternate access mechanisms for this CRL.

4.8.7.  Authority Information Access

   In the context of the RPKI, this extension identifies the publication
   point of the certificate of the issuer of the certificate in which
   the extension appears.  In this profile, a single reference to the
   publication point of the immediate superior certificate MUST be
   present, except for a "self-signed" certificate, in which case the
   extension MUST be omitted.  This extension is non-critical.

   This profile uses a URI form of object identification.  The preferred
   URI access mechanisms is "rsync", and an rsync URI [RFC5781] MUST be
   specified with an accessMethod value of id-ad-caIssuers.  The URI
   MUST reference the point of publication of the certificate where this
   Issuer is the subject (the issuer's immediate superior certificate).
   Other accessMethod URIs referencing the same object MAY also be
   included in the value sequence of this extension.



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   A CA MUST use a persistent URL name scheme for CA certificates that
   it issues [RFC6481].  This implies that a reissued certificate
   overwrites a previously issued certificate (to the same subject) in
   the publication repository.  In this way, certificates subordinate to
   the reissued (CA) certificate can maintain a constant Authority
   Information Access (AIA) extension pointer and thus need not be
   reissued when the parent certificate is reissued.

4.8.8.  Subject Information Access

   In the context of the RPKI, this Subject Information Access (SIA)
   extension identifies the publication point of products signed by the
   subject of the certificate.

4.8.8.1.  SIA for CA Certificates

   This extension MUST be present and MUST be marked non-critical.

   This extension MUST have an instance of an accessMethod of id-ad-
   caRepository, with an accessLocation form of a URI that MUST specify
   an rsync URI [RFC5781].  This URI points to the directory containing
   all published material issued by this CA, i.e., all valid CA
   certificates, published EE certificates, the current CRL, manifest,
   and signed objects validated via EE certificates that have been
   issued by this CA [RFC6481].  Other accessDescription elements with
   an accessMethod of id-ad-caRepository MAY be present.  In such cases,
   the accessLocation values describe alternate supported URI access
   mechanisms for the same directory.  The ordering of URIs in this
   accessDescription sequence reflect the CA's relative preferences for
   access methods to be used by RPs, with the first element of the
   sequence being the most preferred by the CA.

   This extension MUST have an instance of an AccessDescription with an
   accessMethod of id-ad-rpkiManifest,

         id-ad OBJECT IDENTIFIER ::= { id-pkix 48 }

         id-ad-rpkiManifest OBJECT IDENTIFIER ::= { id-ad 10 }

   with an rsync URI [RFC5781] form of accessLocation.  The URI points
   to the CA's manifest of published objects [RFC6486] as an object URL.
   Other accessDescription elements MAY exist for the id-ad-rpkiManifest
   accessMethod, where the accessLocation value indicates alternate
   access mechanisms for the same manifest object.







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4.8.8.2.  SIA for EE Certificates

   This extension MUST be present and MUST be marked non-critical.

   This extension MUST have an instance of an accessMethod of id-ad-
   signedObject,

         id-ad-signedObject OBJECT IDENTIFIER ::= { id-ad 11 }

   with an accessLocation form of a URI that MUST include an rsync URI
   [RFC5781].  This URI points to the signed object that is verified
   using this EE certificate [RFC6481].  Other accessDescription
   elements may exist for the id-ad-signedObject accessMethod, where the
   accessLocation value indicates alternate URI access mechanisms for
   the same object, ordered in terms of the EE's relative preference for
   supported access mechanisms.

   Other AccessMethods MUST NOT be used for an EE certificates's SIA.

4.8.9.  Certificate Policies

   This extension MUST be present and MUST be marked critical.  It MUST
   include exactly one policy, as specified in the RPKI CP [RFC6484]

4.8.10.  IP Resources

   Either the IP Resources extension, or the AS Resources extension, or
   both, MUST be present in all RPKI certificates, and if present, MUST
   be marked critical.

   This extension contains the list of IP address resources as per
   [RFC3779].  The value may specify the "inherit" element for a
   particular Address Family Identifier (AFI) value.  In the context of
   resource certificates describing public number resources for use in
   the public Internet, the Subsequent AFI (SAFI) value MUST NOT be
   used.

   This extension MUST either specify a non-empty set of IP address
   records, or use the "inherit" setting to indicate that the IP address
   resource set of this certificate is inherited from that of the
   certificate's issuer.

4.8.11.  AS Resources

   Either the AS Resources extension, or the IP Resources extension, or
   both, MUST be present in all RPKI certificates, and if present, MUST
   be marked critical.




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   This extension contains the list of AS number resources as per
   [RFC3779], or it may specify the "inherit" element.  Routing Domain
   Identifier (RDI) values are NOT supported in this profile and MUST
   NOT be used.

   This extension MUST either specify a non-empty set of AS number
   records, or use the "inherit" setting to indicate that the AS number
   resource set of this certificate is inherited from that of the
   certificate's issuer.

5.  Resource Certificate Revocation Lists

   Each CA MUST issue a version 2 CRL that is consistent with [RFC5280].
   RPs are NOT required to process version 1 CRLs (in contrast to
   [RFC5280]).  The CRL issuer is the CA.  CRLs conforming to this
   profile MUST NOT include Indirect or Delta CRLs.  The scope of each
   CRL MUST be all certificates issued by this CA.

   The issuer name is as in Section 4.4 above.

   Where two or more CRLs are issued by the same CA, the CRL with the
   highest value of the "CRL Number" field supersedes all other CRLs
   issued by this CA.

   The algorithm used in CRLs issued under this profile is specified in
   [RFC6485].

   The contents of the CRL are a list of all non-expired certificates
   that have been revoked by the CA.

   An RPKI CA MUST include the two extensions, Authority Key Identifier
   and CRL Number, in every CRL that it issues.  RPs MUST be prepared to
   process CRLs with these extensions.  No other CRL extensions are
   allowed.

   For each revoked resource certificate, only the two fields, Serial
   Number and Revocation Date, MUST be present, and all other fields
   MUST NOT be present.  No CRL entry extensions are supported in this
   profile, and CRL entry extensions MUST NOT be present in a CRL.

6.  Resource Certificate Requests

   A resource certificate request MAY use either of PKCS#10 or
   Certificate Request Message Format (CRMF).  A CA MUST support
   certificate issuance in PKCS#10 and a CA MAY support CRMF requests.

   Note that there is no certificate response defined in this profile.
   For CA certificate requests, the CA places the resource certificate



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   in the repository, as per [RFC6484].  No response is defined for EE
   certificate requests.

6.1.  PCKS#10 Profile

   This profile refines the specification in [RFC2986], as it relates to
   resource certificates.  A Certificate Request Message object,
   formatted according to PKCS#10, is passed to a CA as the initial step
   in issuing a certificate.

   With the exception of the SubjectPublicKeyinfo and the SIA extension
   request, the CA is permitted to alter any field in the request when
   issuing a certificate.

6.1.1.  PKCS#10 Resource Certificate Request Template Fields

   This profile applies the following additional requirements to fields
   that MAY appear in a CertificationRequestInfo:

      Version
         This field is mandatory and MUST have the value 0.

      Subject
         This field MAY be omitted.  If present, the value of this field
         SHOULD be empty (i.e., NULL), in which case the CA MUST
         generate a subject name that is unique in the context of
         certificates issued by this CA.  This field is allowed to be
         non-empty only for a re-key/reissuance request, and only if the
         CA has adopted a policy (in its Certificate Practice Statement
         (CPS)) that permits reuse of names in these circumstances.

      SubjectPublicKeyInfo
         This field specifies the subject's public key and the algorithm
         with which the key is used.  The algorithm used in this profile
         is specified in [RFC6485].

      Attributes
         [RFC2986] defines the attributes field as key-value pairs where
         the key is an OID and the value's structure depends on the key.

         The only attribute used in this profile is the extensionRequest
         attribute as defined in [RFC2985].  This attribute contains
         certificate extensions.  The profile for extensions in
         certificate requests is specified in Section 6.3.

   This profile applies the following additional constraint to fields
   that MAY appear in a CertificationRequest Object:




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      signatureAlgorithm
         The signatureAlgorithm value is specified in [RFC6485].

6.2.  CRMF Profile

   This profile refines the Certificate Request Message Format (CRMF)
   specification in [RFC4211], as it relates to resource certificates.
   A Certificate Request Message object, formatted according to the
   CRMF, is passed to a CA as the initial step in certificate issuance.

   With the exception of the SubjectPublicKeyinfo and the SIA extension
   request, the CA is permitted to alter any requested field when
   issuing the certificate.

6.2.1.  CRMF Resource Certificate Request Template Fields

   This profile applies the following additional requirements to fields
   that may appear in a Certificate Request Template:

      version
         This field SHOULD be omitted.  If present, it MUST specify a
         request for a version 3 Certificate.

      serialNumber
         This field MUST be omitted.

      signingAlgorithm
         This field MUST be omitted.

      issuer
         This MUST be omitted in this profile.

      Validity
         This field MAY be omitted.  If omitted, the CA will issue a
         Certificate with Validity dates as determined by the CA.  If
         specified, then the CA MAY override the requested values with
         dates as determined by the CA.

      Subject
         This field MAY be omitted.  If present, the value of this field
         SHOULD be empty (i.e., NULL), in which case the CA MUST
         generate a subject name that is unique in the context of
         certificates issued by this CA.  This field is allowed to be
         non-empty only for a re-key/reissuance request, and only if the
         CA has adopted a policy (in its CPS) that permits the reuse of
         names in these circumstances.





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      PublicKey
         This field MUST be present.

      extensions
         The profile for extensions in certificate requests is specified
         in Section 6.3.

6.2.2.  Resource Certificate Request Control Fields

   The following control fields are supported in this profile:

      Authenticator Control
         The intended model of authentication of the subject is a "long
         term" model, and the guidance offered in [RFC4211] is that the
         Authenticator Control field be used.

6.3.  Certificate Extension Attributes in Certificate Requests

   The following extensions MAY appear in a PKCS#10 or CRMF Certificate
   Request.  Any other extensions MUST NOT appear in a Certificate
   Request.  This profile places the following additional constraints on
   these extensions:

      BasicConstraints
         If this is omitted, then the CA will issue an EE certificate
         (hence no BasicConstraints extension will be included).

         The pathLengthConstraint is not supported in this profile, and
         this field MUST be omitted.

         The CA MAY honor the cA boolean if set to TRUE (CA Certificate
         Request).  If this bit is set, then it indicates that the
         subject is requesting a CA certificate.

         The CA MUST honor the cA bit if set to FALSE (EE Certificate
         Request), in which case the corresponding EE certificate will
         not contain a Basic Constraints extension.

      KeyUsage
         The CA MAY honor KeyUsage extensions of keyCertSign and cRLSign
         if present, as long as this is consistent with the
         BasicConstraints SubjectType sub-field, when specified.

      ExtendedKeyUsage
         The CA MAY honor ExtendedKeyUsage extensions of keyCertSign and
         cRLSign if present, as long as this is consistent with the
         BasicConstraints SubjectType sub-field, when specified.




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      SubjectInformationAccess
         This field MUST be present, and the field value SHOULD be
         honored by the CA if it conforms to the requirements set forth
         in Section 4.8.8.  If the CA is unable to honor the requested
         value for this field, then the CA MUST reject the Certificate
         Request.

7.  Resource Certificate Validation

   This section describes the resource certificate validation procedure.
   This refines the generic procedure described in Section 6 of
   [RFC5280].

7.1.  Resource Extension Validation

   The IP Resources and AS Resources extensions [RFC3779] define
   critical extensions for INRs.  These are ASN.1 encoded
   representations of the IPv4 and IPv6 address range and an AS number
   set.

   Valid resource certificates MUST have a valid IP address and/or AS
   number resource extension.  In order to validate a resource
   certificate, the resource extension MUST also be validated.  This
   validation process relies on definitions of comparison of resource
   sets:

      more specific
         Given two contiguous IP address ranges or two contiguous AS
         number ranges, A and B, A is "more specific" than B if range B
         includes all IP addresses or AS numbers described by range A,
         and if range B is larger than range A.

      equal
         Given two contiguous IP address ranges or two contiguous AS
         number ranges, A and B, A is "equal" to B if range A describes
         precisely the same collection of IP addresses or AS numbers
         described by range B. The definition of "inheritance" in
         [RFC3779] is equivalent to this "equality" comparison.

      encompass
         Given two IP address and AS number sets, X and Y, X
         "encompasses" Y if, for every contiguous range of IP addresses
         or AS numbers elements in set Y, the range element is either
         "more specific" than or "equal" to a contiguous range element
         within the set X.

   Validation of a certificate's resource extension in the context of a
   certification path (see Section 7.2 entails that for every adjacent



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   pair of certificates in the certification path (certificates 'x' and
   'x + 1'), the number resources described in certificate 'x'
   "encompass" the number resources described in certificate 'x + 1',
   and the resources described in the trust anchor information
   "encompass" the resources described in the first certificate in the
   certification path.

7.2.  Resource Certification Path Validation

   Validation of signed resource data using a target resource
   certificate consists of verifying that the digital signature of the
   signed resource data is valid, using the public key of the target
   resource certificate, and also validating the resource certificate in
   the context of the RPKI, using the path validation process.  This
   path validation process verifies, among other things, that a
   prospective certification path (a sequence of n certificates)
   satisfies the following conditions:

      1.  for all 'x' in {1, ..., n-1}, the subject of certificate 'x'
          is the issuer of certificate ('x' + 1);

      2.  certificate '1' is issued by a trust anchor;

      3.  certificate 'n' is the certificate to be validated; and

      4.  for all 'x' in {1, ..., n}, certificate 'x' is valid.

   Certificate validation entails verifying that all of the following
   conditions hold, in addition to the certification path validation
   criteria specified in Section 6 of [RFC5280]:

      1.  The certificate can be verified using the issuer's public key
          and the signature algorithm

      2.  The current time lies within the certificate's Validity From
          and To values.

      3.  The certificate contains all fields that MUST be present, as
          defined by this specification, and contains values for
          selected fields that are defined as allowable values by this
          specification.

      4.  No field, or field value, that this specification defines as
          MUST NOT be present is used in the certificate.

      5.  The issuer has not revoked the certificate.  A revoked
          certificate is identified by the certificate's serial number
          being listed on the issuer's current CRL, as identified by the



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          CRLDP of the certificate, the CRL is itself valid, and the
          public key used to verify the signature on the CRL is the same
          public key used to verify the certificate itself.

      6.  The resource extension data is "encompassed" by the resource
          extension data contained in a valid certificate where this
          issuer is the subject (the previous certificate in the context
          of the ordered sequence defined by the certification path).

      7.  The certification path originates with a certificate issued by
          a trust anchor, and there exists a signing chain across the
          certification path where the subject of Certificate 'x' in the
          certification path matches the issuer in Certificate 'x + 1'
          in the certification path, and the public key in Certificate
          'x' can verify the signature value in Certificate 'x+1'.

   A certificate validation algorithm MAY perform these tests in any
   chosen order.

   Certificates and CRLs used in this process MAY be found in a locally
   maintained cache, maintained by a regular synchronization across the
   distributed publication repository structure [RFC6481].

   There exists the possibility of encountering certificate paths that
   are arbitrarily long, or attempting to generate paths with loops as
   means of creating a potential denial-of-service (DOS) attack on an
   RP.  An RP executing this procedure MAY apply further heuristics to
   guide the certification path validation process to a halt in order to
   avoid some of the issues associated with attempts to validate such
   malformed certification path structures.  Implementations of resource
   certificate validation MAY halt with a validation failure if the
   certification path length exceeds a locally defined configuration
   parameter.

8.  Design Notes

   The following notes provide some additional commentary on the
   considerations that lie behind some of the design choices that were
   made in the design of this certificate profile.  These notes are
   non-normative, i.e., this section of the document does not constitute
   a formal part of the profile specification, and the interpretation of
   key words as defined in RFC 2119 are not applicable in this section
   of the document.








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   Certificate Extensions:
         This profile does not permit the use of any other critical or
         non-critical extensions.  The rationale for this restriction is
         that the resource certificate profile is intended for a
         specific defined use.  In this context, having certificates
         with additional non-critical extensions that RPs may see as
         valid certificates without understanding the extensions is
         inappropriate, because if the RP were in a position to
         understand the extensions, it would contradict or qualify this
         original judgment of validity in some way.  This profile takes
         the position of minimalism over extensibility.  The specific
         goal for the associated RPKI is to precisely match the INR
         allocation structure through an aligned certificate structure
         that describes the allocation and its context within the INR
         distribution hierarchy.  The profile defines a resource
         certificate that is structured to meet these requirements.

   Certification Authorities and Key Values:
         This profile uses a definition of an instance of a CA as a
         combination of a named entity and a key pair.  Within this
         definition, a CA instance cannot rollover a key pair.  However,
         the entity can generate a new instance of a CA with a new key
         pair and roll over all the signed subordinate products to the
         new CA [RFC6489].

         This has a number of implications in terms of subject name
         management, CRL Scope, and repository publication point
         management.

   CRL Scope and Key Values:
         For CRL Scope, this profile specifies that a CA issues a single
         CRL at a time, and the scope of the CRL is all certificates
         issued by this CA.  Because the CA instance is bound to a
         single key pair, this implies that the CA's public key, the key
         used to validate the CA's CRL, and the key used to validate the
         certificates revoked by that CRL are all the same key value.

   Repository Publication Point:
         The definition of a CA affects the design of the repository
         publication system.  In order to minimize the amount of forced
         re-certification on key rollover events, a repository
         publication regime that uses the same repository publication
         point for all CA instances that refers to the same entity, but
         with different key values, will minimize the extent of
         re-generation of certificates to only immediate subordinate
         certificates.  This is described in [RFC6489].





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   Subject Name:
         This profile specifies that subject names must be unique per
         issuer, and does not specify that subject names must be
         globally unique (in terms of assured uniqueness).  This is due
         to the nature of the RPKI as a distributed PKI, implying that
         there is no ready ability for certification authorities to
         coordinate a simple RPKI-wide unique name space without
         resorting to additional critical external dependencies.  CAs
         are advised to use subject name generation procedures that
         minimize the potential for name clashes.

         One way to achieve this is for a CA to use a subject name
         practice that uses the CommonName component of the
         Distinguished Name as a constant value for any given entity
         that is the subject of CA-issued certificates, and set the
         serialNumber component of the Distinguished Name to a value
         that is derived from the hash of the subject public key value.

         If the CA elects not to use the serialNumber component of the
         DistinguishedName, then it is considered beneficial that a CA
         generates CommonNames that have themselves a random component
         that includes significantly more than 40 bits of entropy in the
         name.  Some non-normative recommendations to achieve this
         include:

         1) Hash of the subject public key (encoded as ASCII HEX).
            example: cn="999d99d564de366a29cd8468c45ede1848e2cc14"

         2) A Universally Unique IDentifier (UUID) [RFC4122]
            example: cn="6437d442-6fb5-49ba-bbdb-19c260652098"

         3) A randomly generated ASCII HEX encoded string of length 20
            or greater:
            example: cn="0f8fcc28e3be4869bc5f8fa114db05e1">
            (A string of 20 ASCII HEX digits would have 80-bits of
            entropy)

         4) An internal database key or subscriber ID combined with one
            of the above
            example: cn="<DBkey1> (6437d442-6fb5-49ba-bbdb-
            19c2606520980)"
            (The issuing CA may wish to be able to extract the database
            key or subscriber ID from the commonName.  Since only the
            issuing CA would need to be able to parse the commonName,
            the database key and the source of entropy (e.g., a UUID)
            could be separated in any way that the CA wants, as long as
            it conforms to the rules for PrintableString.  The separator




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            could be a space character, parenthesis, hyphen, slash,
            question mark, etc.

9.  Operational Considerations for Profile Agility

   This profile requires that relying parties reject certificates or
   CRLs that do not conform to the profile.  (Through the remainder of
   this section, the term "certificate" is used to refer to both
   certificates and CRLs.)  This includes certificates that contain
   extensions that are prohibited, but that are otherwise valid as per
   [RFC5280].  This means that any change in the profile (e.g.,
   extensions, permitted attributes or optional fields, or field
   encodings) for certificates used in the RPKI will not be backward
   compatible.  In a general PKI context, this constraint probably would
   cause serious problems.  In the RPKI, several factors minimize the
   difficulty of effecting changes of this sort.

   Note that the RPKI is unique in that every relying party (RP)
   requires access to every certificate issued by the CAs in this
   system.  An important update of the certificates used in the RPKI
   must be supported by all CAs and RPs in the system, lest views of the
   RPKI data differ across RPs.  Thus, incremental changes require very
   careful coordination.  It would not be appropriate to introduce a new
   extension, or authorize use of an extant, standard extension, for a
   security-relevant purpose on a piecemeal basis.

   One might imagine that the "critical" flag in X.509 certificate
   extensions could be used to ameliorate this problem.  However, this
   solution is not comprehensive and does not address the problem of
   adding a new, security-critical extension.  (This is because such an
   extension needs to be supported universally, by all CAs and RPs.)
   Also, while some standard extensions can be marked either critical or
   non-critical, at the discretion of the issuer, not all have this
   property, i.e., some standard extensions are always non-critical.
   Moreover, there is no notion of criticality for attributes within a
   name or optional fields within a field or an extension.  Thus, the
   critical flag is not a solution to this problem.

   In typical PKI deployments, there are few CAs and many RPs.  However,
   in the RPKI, essentially every CA in the RPKI is also an RP.  Thus
   the set of entities that will need to change in order to issue
   certificates under a new format is the same set of entities that will
   need to change to accept these new certificates.  To the extent that
   this is literally true, it says that CA/RP coordination for a change
   is tightly linked anyway.  In reality, there is an important
   exception to this general observation.  Small ISPs and holders of
   provider-independent allocations are expected to use managed CA
   services, offered by Regional Internet Registries (RIRs) and



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   potentially by wholesale Internet Service Providers (ISPs).  This
   reduces the number of distinct CA implementations that are needed and
   makes it easier to effect changes for certificate issuance.  It seems
   very likely that these entities also will make use of RP software
   provided by their managed CA service provider, which reduces the
   number of distinct RP software implementations.  Also note that many
   small ISPs (and holders of provider-independent allocations) employ
   default routes, and thus need not perform RP validation of RPKI data,
   eliminating these entities as RPs.

   Widely available PKI RP software does not cache large numbers of
   certificates, an essential strategy for the RPKI.  It does not
   process manifest or ROA data structures, essential elements of the
   RPKI repository system.  Experience shows that such software deals
   poorly with revocation status data.  Thus, extant RP software is not
   adequate for the RPKI, although some open source tools (e.g., OpenSSL
   and cryptlib) can be used as building blocks for an RPKI RP
   implementation.  Thus, it is anticipated that RPs will make use of
   software that is designed specifically for the RPKI environment and
   is available from a limited number of open sources.  Several RIRs and
   two companies are providing such software today.  Thus it is feasible
   to coordinate change to this software among the small number of
   developers/maintainers.

   If the resource certificate profile is changed in the future, e.g.,
   by adding a new extension or changing the allowed set of name
   attributes or encoding of these attributes, the following procedure
   will be employed to effect deployment in the RPKI.  The model is
   analogous to that described in [RPKI-ALG], but is simpler.

   A new document will be issued as an update to this RFC.  The CP for
   the RPKI [RFC6484] will be updated to reference the new certificate
   profile.  The new CP will define a new policy OID for certificates
   issued under the new certificate profile.  The updated CP also will
   define a timeline for transition to the new certificate (CRL) format.
   This timeline will define 3 phases and associated dates:

      1.  At the end of phase 1, all RPKI CAs MUST be capable of issuing
          certificates under the new profile, if requested by a subject.
          Any certificate issued under the new format will contain the
          new policy OID.

      2.  During phase 2, CAs MUST issue certificates under the new
          profile, and these certificates MUST coexist with certificates
          issued under the old format.  (CAs will continue to issue
          certificates under the old OID/format as well.)  The old and
          new certificates MUST be identical, except for the policy OID
          and any new extensions, encodings, etc.  The new certificates,



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          and associated signed objects, will coexist in the RPKI
          repository system during this phase, analogous to what is
          required by an algorithm transition for the RPKI [RPKI-ALG].
          Relying parties MAY make use of the old or the new certificate
          formats when processing signed objects retrieved from the RPKI
          repository system.  During this phase, a relying party that
          elects to process both formats will acquire the same values
          for all certificate fields that overlap between the old and
          new formats.  Thus if either certificate format is verifiable,
          the relying party accepts the data from that certificate.
          This allows CAs to issue certificates under the new format
          before all relying parties are prepared to process that
          format.

      3.  At the beginning of phase 3, all relying parties MUST be
          capable of processing certificates under the new format.
          During this phase, CAs will issue new certificates ONLY under
          the new format.  Certificates issued under the old OID will be
          replaced with certificates containing the new policy OID.  The
          repository system will no longer require matching old and new
          certificates under the different formats.

   At the end of phase 3, all certificates under the old OID will have
   been replaced.  The resource certificate profile RFC will be replaced
   to remove support for the old certificate format, and the CP will be
   replaced to remove reference to the old policy OID and to the old
   resource certificate profile RFC.  The system will have returned to a
   new, steady state.

10.  Security Considerations

   The Security Considerations of [RFC5280] and [RFC3779] apply to
   resource certificates.  The Security Considerations of [RFC2986] and
   [RFC4211] apply to resource certificate certification requests.

   A resource certificate PKI cannot in and of itself resolve any forms
   of ambiguity relating to uniqueness of assertions of rights of use in
   the event that two or more valid certificates encompass the same
   resource.  If the issuance of resource certificates is aligned to the
   status of resource allocations and assignments, then the information
   conveyed in a certificate is no better than the information in the
   allocation and assignment databases.

   This profile requires that the key used to sign an issued certificate
   be the same key used to sign the CRL that can revoke the certificate,
   implying that the certification path used to validate the signature
   on a certificate is the same as that used to validate the signature
   of the CRL that can revoke the certificate.  It is noted that this is



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   a tighter constraint than required in X.509 PKIs, and there may be a
   risk in using a path validation implementation that is capable of
   using separate validation paths for a certificate and the
   corresponding CRL.  If there are subject name collisions in the RPKI
   as a result of CAs not following the guidelines provided here
   relating to ensuring sufficient entropy in constructing subject
   names, and this is combined with the situation that an RP uses an
   implementation of validation path construction that is not in
   conformance with this RPKI profile, then it is possible that the
   subject name collisions can cause an RP to conclude that an otherwise
   valid certificate has been revoked.

11.  Acknowledgements

   The authors would like to particularly acknowledge the valued
   contribution from Stephen Kent in reviewing this document and
   proposing numerous sections of text that have been incorporated into
   the document.  The authors also acknowledge the contributions of
   Sandy Murphy, Robert Kisteleki, Randy Bush, Russ Housley, Ricardo
   Patara, and Rob Austein in the preparation and subsequent review of
   this document.  The document also reflects review comments received
   from Roque Gagliano, Sean Turner, and David Cooper.

12.  References

12.1.  Normative References

   [RFC2119]   Bradner, S., "Key words for use in RFCs to Indicate
               Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2986]   Nystrom, M. and B. Kaliski, "PKCS #10: Certification
               Request Syntax Specification Version 1.7", RFC 2986,
               November 2000.

   [RFC3779]   Lynn, C., Kent, S., and K. Seo, "X.509 Extensions for IP
               Addresses and AS Identifiers", RFC 3779, June 2004.

   [RFC4211]   Schaad, J., "Internet X.509 Public Key Infrastructure
               Certificate Request Message Format (CRMF)", RFC 4211,
               September 2005.

   [RFC5280]   Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
               Housley, R., and W. Polk, "Internet X.509 Public Key
               Infrastructure Certificate and Certificate Revocation
               List (CRL) Profile", RFC 5280, May 2008.

   [RFC5781]   Weiler, S., Ward, D., and R. Housley, "The rsync URI
               Scheme", RFC 5781, February 2010.



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   [RFC6484]   Kent, S., Kong, D., Seo, K., and R. Watro, "Certificate
               Policy (CP) for the Resource Public Key Infrastructure
               (RPKI)", BCP 173, RFC 6484, February 2012.

   [RFC6485]   Huston, G., "The Profile for Algorithms and Key Sizes for
               Use in the Resource Public Key Infrastructure (RPKI)",
               RFC 6485, February 2012.

   [X.509]     ITU-T, "Recommendation X.509: The Directory -
               Authentication Framework", 2000.

   [X.680]     ITU-T, "Recommendation X.680 (2002) | ISO/IEC 8824-
               1:2002, Information technology - Abstract Syntax Notation
               One (ASN.1): Specification of basic notation", 2002.

12.2.  Informative References

   [RFC2985]   Nystrom, M. and B. Kaliski, "PKCS #9: Selected Object
               Classes and Attribute Types Version 2.0", RFC 2985,
               November 2000.

   [RFC3986]   Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
               Resource Identifier (URI): Generic Syntax", STD 66,
               RFC 3986, January 2005.

   [RFC4122]   Leach, P., Mealling, M., and R. Salz, "A Universally
               Unique IDentifier (UUID) URN Namespace", RFC 4122,
               July 2005.

   [RFC4514]   Zeilenga, K., "Lightweight Directory Access Protocol
               (LDAP): String Representation of Distinguished Names",
               RFC 4514, June 2006.

   [RFC6480]   Lepinski, M. and S. Kent, "An Infrastructure to Support
               Secure Internet Routing", RFC 6480, February 2012.

   [RFC6481]   Huston, G., Loomans, R., and G. Michaelson, "A Profile
               for Resource Certificate Repository Structure", RFC 6481,
               February 2012.

   [RFC6486]   Austein, R., Huston, G., Kent, S., and M. Lepinski,
               "Manifests for the Resource Public Key Infrastructure
               (RPKI)", RFC 6486, February 2012.

   [RFC6488]   Lepinski, M., Chi, A., and S. Kent, "Signed Object
               Template for the Resource Public Key Infrastructure
               (RPKI)", RFC 6488, February 2012.




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   [RFC6489]   Huston, G., Michaelson, G., and S. Kent, "Certification
               Authority (CA) Key Rollover in the Resource Public Key
               Infrastructure (RPKI)", BCP 174, RFC 6489, February 2012.

   [RPKI-ALG]  Gagliano, R., Kent, S., and S. Turner, "Algorithm Agility
               Procedure for RPKI", Work in Progress, November 2011.













































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Appendix A.  Example Resource Certificate

   The following is an example resource certificate.

   Certificate Name: 9JfgAEcq7Q-47IwMC5CJIJr6EJs.cer

   Data:
     Version: 3 (0x2)
     Serial: 1500 (0x5dc)
     Signature Algorithm: SHA256WithRSAEncryption
     Issuer: CN=APNIC Production-CVPQSgUkLy7pOXdNeVWGvnFX_0s
     Validity
      Not Before: Oct 25 12:50:00 2008 GMT
       Not After : Jan 31 00:00:00 2010 GMT
     Subject: CN=A91872ED
     Subject Public Key Info:
       Public Key Algorithm: rsaEncryption
       RSA Public Key: (2048 bit)
       Modulus (2048 bit):
         00:bb:fb:4a:af:a4:b9:dc:d0:fa:6f:67:cc:27:39:
         34:d1:80:40:37:de:88:d1:64:a2:f1:b3:fa:c6:7f:
         bb:51:df:e1:c7:13:92:c3:c8:a2:aa:8c:d1:11:b3:
         aa:99:c0:ac:54:d3:65:83:c6:13:bf:0d:9f:33:2d:
         39:9f:ab:5f:cd:a3:e9:a1:fb:80:7d:1d:d0:2b:48:
         a5:55:e6:24:1f:06:41:35:1d:00:da:1f:99:85:13:
         26:39:24:c5:9a:81:15:98:fb:5f:f9:84:38:e5:d6:
         70:ce:5a:02:ca:dd:61:85:b3:43:2d:0b:35:d5:91:
         98:9d:da:1e:0f:c2:f6:97:b7:97:3e:e6:fc:c1:c4:
         3f:30:c4:81:03:25:99:09:4c:e2:4a:85:e7:46:4b:
         60:63:02:43:46:51:4d:ed:fd:a1:06:84:f1:4e:98:
         32:da:27:ee:80:82:d4:6b:cf:31:ea:21:af:6f:bd:
         70:34:e9:3f:d7:e4:24:cd:b8:e0:0f:8e:80:eb:11:
         1f:bc:c5:7e:05:8e:5c:7b:96:26:f8:2c:17:30:7d:
         08:9e:a4:72:66:f5:ca:23:2b:f2:ce:54:ec:4d:d9:
         d9:81:72:80:19:95:57:da:91:00:d9:b1:e8:8c:33:
         4a:9d:3c:4a:94:bf:74:4c:30:72:9b:1e:f5:8b:00:
         4d:e3
       Exponent: 65537 (0x10001)
     X509v3 extensions:
       X509v3 Subject Key Identifier:
         F4:97:E0:00:47:2A:ED:0F:B8:EC:8C:0C:0B:90:89:
         20:9A:FA:10:9B

       X509v3 Authority Key Identifier:
         keyid:09:53:D0:4A:05:24:2F:2E:E9:39:77:4D:79:
         55:86:BE:71:57:FF:4B





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RFC 6487              Resource Certificate Profile         February 2012


       X509v3 Key Usage: critical
         Certificate Sign, CRL Sign

       X509v3 Basic Constraints: critical
         CA:TRUE

       X509v3 CRL Distribution Points:
         URI:rsync://rpki.apnic.net/repository/A3C38A24
             D60311DCAB08F31979BDBE39/CVPQSgUkLy7pOXdNe
             VWGvnFX_0s.crl

       Authority Information Access:
          CA Issuers - URI:rsync://rpki.apnic.net/repos
             itory/8BDFC7DED5FD11DCB14CF4B1A703F9B7/CVP
             QSgUkLy7pOXdNeVWGvnFX_0s.cer

       X509v3 Certificate Policies: critical
          Policy: 1.3.6.1.5.5.7.14.2

       Subject Information Access:
          CA Repository - URI:rsync://rpki.apnic.net/mem
              ber_repository/A91872ED/06A83982887911DD81
              3F432B2086D636/
          Manifest - URI:rsync://rpki.apnic.net/member_r
              epository/A91872ED/06A83982887911DD813F432
              B2086D636/9JfgAEcq7Q-47IwMC5CJIJr6EJs.mft

        sbgp-autonomousSysNum: critical
          Autonomous System Numbers:
            24021
            38610
            131072
            131074

        sbgp-ipAddrBlock: critical
          IPv4:
            203.133.248.0/22
            203.147.108.0/23













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RFC 6487              Resource Certificate Profile         February 2012


   Signature Algorithm: sha256WithRSAEncryption
       51:4c:77:e4:21:64:80:e9:35:30:20:9f:d8:4b:88:60:b8:1f:
       73:24:9d:b5:17:60:65:6a:28:cc:43:4b:68:97:ca:76:07:eb:
       dc:bd:a2:08:3c:8c:56:38:c6:0a:1e:a8:af:f5:b9:42:02:6b:
       77:e0:b1:1c:4a:88:e6:6f:b6:17:d3:59:41:d7:a0:62:86:59:
       29:79:26:76:34:d1:16:2d:75:05:cb:b2:99:bf:ca:c6:68:1b:
       b6:a9:b0:f4:43:2e:df:e3:7f:3c:b3:72:1a:99:fa:5d:94:a1:
       eb:57:9c:9a:2c:87:d6:40:32:c9:ff:a6:54:b8:91:87:fd:90:
       55:ef:12:3e:1e:2e:cf:c5:ea:c3:4c:09:62:4f:88:00:a0:7f:
       cd:67:83:bc:27:e1:74:2c:18:4e:3f:12:1d:ef:29:0f:e3:27:
       00:ce:14:eb:f0:01:f0:36:25:a2:33:a8:c6:2f:31:18:22:30:
       cf:ca:97:43:ed:84:75:53:ab:b7:6c:75:f7:2f:55:5c:2e:82:
       0a:be:91:59:bf:c9:06:ef:bb:b4:a2:71:9e:03:b1:25:8e:29:
       7a:30:88:66:b4:f2:16:6e:df:ad:78:ff:d3:b2:9c:29:48:e3:
       be:87:5c:fc:20:2b:df:da:ca:30:58:c3:04:c9:63:72:48:8c:
       0a:5f:97:71



































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RFC 6487              Resource Certificate Profile         February 2012


Appendix B.  Example Certificate Revocation List

   The following is an example Certificate Revocation List.

   CRL Name: q66IrWSGuBE7jqx8PAUHAlHCqRw.crl
   Data:
     Version: 2
     Signature Algorithm:
       Hash: SHA256, Encryption: RSA
     Issuer: CN=Demo Production APNIC CA - Not for real use,
       E=ca@apnic.net
     This Update: Thu Jul 27 06:30:34 2006 GMT
     Next Update: Fri Jul 28 06:30:34 2006 GMT
     Authority Key Identifier: Key Identifier:
       ab:ae:88:ad:64:86:b8:11:3b:8e:ac:7c:3c:05:
       07:02:51:c2:a9:1c
     CRLNumber: 4
     Revoked Certificates: 1
       Serial Number: 1
       Revocation Date: Mon Jul 17 05:10:19 2006 GMT
       Serial Number: 2
       Revocation Date: Mon Jul 17 05:12:25 2006 GMT
       Serial Number: 4
       Revocation Date: Mon Jul 17 05:40:39 2006 GMT
     Signature:
       b2:5a:e8:7c:bd:a8:00:0f:03:1a:17:fd:40:2c:46:
       0e:d5:64:87:e7:e7:bc:10:7d:b6:3e:39:21:a9:12:
       f4:5a:d8:b8:d4:bd:57:1a:7d:2f:7c:0d:c6:4f:27:
       17:c8:0e:ae:8c:89:ff:00:f7:81:97:c3:a1:6a:0a:
       f7:d2:46:06:9a:d1:d5:4d:78:e1:b7:b0:58:4d:09:
       d6:7c:1e:a0:40:af:86:5d:8c:c9:48:f6:e6:20:2e:
       b9:b6:81:03:0b:51:ac:23:db:9f:c1:8e:d6:94:54:
       66:a5:68:52:ee:dd:0f:10:5d:21:b8:b8:19:ff:29:
       6f:51:2e:c8:74:5c:2a:d2:c5:fa:99:eb:c5:c2:a2:
       d0:96:fc:54:b3:ba:80:4b:92:7f:85:54:76:c9:12:
       cb:32:ea:1d:12:7b:f8:f9:a2:5c:a1:b1:06:8e:d8:
       c5:42:61:00:8c:f6:33:11:29:df:6e:b2:cc:c3:7c:
       d3:f3:0c:8d:5c:49:a5:fb:49:fd:e7:c4:73:68:0a:
       09:0e:6d:68:a9:06:52:3a:36:4f:19:47:83:59:da:
       02:5b:2a:d0:8a:7a:33:0a:d5:ce:be:b5:a2:7d:8d:
       59:a1:9d:ee:60:ce:77:3d:e1:86:9a:84:93:90:9f:
       34:a7:02:40:59:3a:a5:d1:18:fb:6f:fc:af:d4:02:
       d9








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RFC 6487              Resource Certificate Profile         February 2012


Authors' Addresses

   Geoff Huston
   APNIC

   EMail: gih@apnic.net
   URI:   http://www.apnic.net


   George Michaelson
   APNIC

   EMail: ggm@apnic.net
   URI:   http://www.apnic.net


   Robert Loomans
   APNIC

   EMail: robertl@apnic.net
   URI:   http://www.apnic.net






























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