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Versions: (draft-huston-sidr-res-certs) 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 RFC 6487

SIDR                                                           G. Huston
Internet-Draft                                                R. Loomans
Intended status: Best Current                              G. Michaelson
Practice                                                           APNIC
Expires: December 21, 2006                                 June 19, 2006


             A Profile for X.509 PKIX Resource Certificates
                    draft-ietf-sidr-res-certs-01.txt

Status of this Memo

   By submitting this Internet-Draft, each author represents that any
   applicable patent or other IPR claims of which he or she is aware
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   This Internet-Draft will expire on December 21, 2006.

Copyright Notice

   Copyright (C) The Internet Society (2006).

Abstract

   This document defines a profile for X.509 certificates for the
   purposes of supporting validation of assertions of "right-to- use" of
   an Internet Number Resource (IP Addresses and Autonomous System
   Numbers).  This profile is used to convey the authorization of the
   subject to be regarded as the current unique controlled of the IP
   addresses and AS numbers that are described in a Resource
   Certificate.



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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  4
     1.1.  Terminology  . . . . . . . . . . . . . . . . . . . . . . .  4
   2.  Describing Resources in Certificates . . . . . . . . . . . . .  5
   3.  Resource Certificate Fields  . . . . . . . . . . . . . . . . .  6
     3.1.  Version  . . . . . . . . . . . . . . . . . . . . . . . . .  6
     3.2.  Serial number  . . . . . . . . . . . . . . . . . . . . . .  6
     3.3.  Signature Algorithm  . . . . . . . . . . . . . . . . . . .  6
     3.4.  Issuer . . . . . . . . . . . . . . . . . . . . . . . . . .  6
     3.5.  Subject  . . . . . . . . . . . . . . . . . . . . . . . . .  6
     3.6.  Valid From . . . . . . . . . . . . . . . . . . . . . . . .  6
     3.7.  Valid To . . . . . . . . . . . . . . . . . . . . . . . . .  7
     3.8.  Subject Public Key Info  . . . . . . . . . . . . . . . . .  7
     3.9.  Resource Certificate Version 3 Extension Fields  . . . . .  7
       3.9.1.  Basic Constraints  . . . . . . . . . . . . . . . . . .  7
       3.9.2.  Subject Key Identifier . . . . . . . . . . . . . . . .  8
       3.9.3.  Authority Key Identifier . . . . . . . . . . . . . . .  8
       3.9.4.  Key Usage  . . . . . . . . . . . . . . . . . . . . . .  8
       3.9.5.  CRL Distribution Points  . . . . . . . . . . . . . . .  9
       3.9.6.  Authority Information Access . . . . . . . . . . . . .  9
       3.9.7.  Subject Information Access . . . . . . . . . . . . . . 10
       3.9.8.  Certificate Policies . . . . . . . . . . . . . . . . . 11
       3.9.9.  Subject Alternate Name . . . . . . . . . . . . . . . . 11
       3.9.10. IP Resources . . . . . . . . . . . . . . . . . . . . . 11
       3.9.11. AS Resources . . . . . . . . . . . . . . . . . . . . . 11
   4.  Resource Certificate Revocation List Profile . . . . . . . . . 11
     4.1.  Version  . . . . . . . . . . . . . . . . . . . . . . . . . 12
     4.2.  Issuer Name  . . . . . . . . . . . . . . . . . . . . . . . 12
     4.3.  This Update  . . . . . . . . . . . . . . . . . . . . . . . 12
     4.4.  Next Update  . . . . . . . . . . . . . . . . . . . . . . . 12
     4.5.  Signature  . . . . . . . . . . . . . . . . . . . . . . . . 12
     4.6.  Revoked Certificate List . . . . . . . . . . . . . . . . . 13
       4.6.1.  Serial Number  . . . . . . . . . . . . . . . . . . . . 13
       4.6.2.  Revocation Date  . . . . . . . . . . . . . . . . . . . 13
     4.7.  CRL Extensions . . . . . . . . . . . . . . . . . . . . . . 13
       4.7.1.  Authority Key Identifier . . . . . . . . . . . . . . . 13
       4.7.2.  CRL Number . . . . . . . . . . . . . . . . . . . . . . 13
   5.  Resource Certificate Request Profile . . . . . . . . . . . . . 14
     5.1.  Resource Certificate Request Template Fields . . . . . . . 14
     5.2.  Resource Certificate Request Control Fields  . . . . . . . 17
   6.  Resource Certificate Validation  . . . . . . . . . . . . . . . 18
     6.1.  Trust Anchors for Resource Certificates  . . . . . . . . . 19
     6.2.  Resource Extension Validation  . . . . . . . . . . . . . . 20
     6.3.  Resource Certificate Path Validation . . . . . . . . . . . 20
   7.  Security Considerations  . . . . . . . . . . . . . . . . . . . 22
   8.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 22
   9.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 22



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   10. Normative References . . . . . . . . . . . . . . . . . . . . . 22
   Appendix A.  Example Resource Certificate  . . . . . . . . . . . . 23
   Appendix B.  Example Certificate Revocation List . . . . . . . . . 24
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 25
   Intellectual Property and Copyright Statements . . . . . . . . . . 26














































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1.  Introduction

   This document defines a profile for X.509 certificates for use in the
   context of Resources Certificates.  Resource Certificates are X.509
   certificates that conform to the PKIX profile [RFC3280] and to this
   additional profile, and attest that the subject has the "right-to-
   use" a listed set of IP addresses and Autonomous Numbers.

   A Resource Certificate describes an action by an Issuer that binds a
   list of IP address blocks and AS numbers to the Subject of a
   certificate, identified by the unique association of the Subject's
   private key with the public key contained in the Resource
   Certificate.

   In the context of the public Internet it is intended that Resource
   Certificates are used in a manner that is aligned to the public
   number resource distribution function, Specifically, when a number
   resource is allocated or assigned by a Registry to an entity, this
   allocation is described by a Resource Certificate issued by the
   Registry with a subject corresponding to the entity that is the
   recipient of this assignment or allocation.  This corresponds to a
   hierarchical PKI structure, where Resource Certificates are only
   issued in one 'direction' and there is a single unique path from a
   "Root CA" to any valid certificate.

   Validation of a certificate in such a hierarchical PKI can be
   undertaken by creating a valid issuer - subject chain from the trust
   anchor allocation authorities to the certificate [RFC4158].

   Resource Certificates may be used in the context of secure inter-
   domain routing protocols to convey a right-to-use of an IP number
   resource that is being passed within the routing protocol, to verify
   legitimacy and correctness of routing information.  Related use
   contexts include validation of access to Internet Routing Registries
   for nominated routing objects, validation of routing requests, and
   detection of potential unauthorized used of IP addresses.

   This profile defines those fields that are used in a Resource
   Certificate that MUST be present for the certificate to be valid.
   Relying Parties SHOULD check that a Resource Certificate conforms to
   this profile as a requisite for validation of a Resource Certificate.

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" [RFC3280], "X.509
   Extensions for IP Addresses and AS Identifiers" [RFC3779], "Internet



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   Protocol" [RFC0791], "Internet Protocol Version 6 (IPv6) Addressing
   Architecture" [RFC4291], "Internet Registry IP Allocation Guidelines"
   [RFC2050], and related regional Internet registry address management
   policy documents.

   The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119.


2.  Describing Resources in Certificates

   The framework for describing an association between the subject of a
   certificate and the resources currently under the subject's current
   control is described in [RFC3779].

   There are three aspects of this resource extension that are noted in
   this profile:

   1.  RFC 3779 notes that this resource extension SHOULD be a CRITICAL
       extension to the X.509 Certificate.  This Resource Certificate
       profile further defines that the use of this certificate
       extension MUST be used and MUST be marked as CRITICAL.

   2.  RFC 3779 defines a sorted canonical form of describing a resource
       set, with maximal spanning ranges and maximal spanning prefix
       masks as appropriate.  All valid certificates in this profile
       MUST use this sorted canonical form of resource description

   3.  A test of the resource extension in the context of certificate
       unique value token within the context of certificates issued by
       the validity includes the first condition that the resources
       described in the Issuer's resource extension must encompass those
       of the Subject's resource extension.  In this context "encompass"
       allows for the Issuer's resource set to be the same as, or a
       strict superset of, any subject's resource set.  Certificate
       validity in the context of this profile also includes a second
       condition that no two (or more) certificates issued by a single
       Issuer to two (or more) different subjects have a non-null
       intersection of resources.  In other words an Issuer can certify
       at most one unique subject as the unique holder of a right-to-use
       for any particular resource.

   This implies that a test of certificate validity implies that there
   exists a set of valid certificates in an issuer-subject chain from
   one, and only one, trust anchor to the certificate in question, and
   that the resource extensions from the trust anchor to the certificate
   form a sequence of encompassing relationships.



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3.  Resource Certificate Fields

   A Resource Certificate is a valid X.509 v3 public key certificate,
   consistent with the PKIX profile [RFC3280], containing the fields
   listed in this section.  Unless specifically noted as being OPTIONAL,
   all the fields listed here MUST be present, and any other field MUST
   NOT appear in a conforming Resource Certificate.  Where a field value
   is specified here this value MUST be used in conforming Resource
   Certificates.

3.1.  Version

   Resource Certificates are X.509 Version 3 certificates.  This field
   MUST be present, and the Version MUST be 3 (i.e. the value of this
   field is 2).

3.2.  Serial number

   The serial number value is a positive integer that is unique per
   Issuer.

3.3.  Signature Algorithm

   This field describes the algorithm used to compute the signature on
   this certificate.  This profile uses SHA-256 with RSA
   (sha256WithRSAEncryption), and the value for this field MUST be the
   OID value 1.2.840.113549.1.1.11 [RFC4055].

3.4.  Issuer

   This field identifies the entity that has signed and issued the
   certificate.  The value of this field is an X.501 name.

3.5.  Subject

   This field identifies the entity to whom the resource has been
   allocated / assigned.  The value of this field is an X.500 name.  In
   this profile the subject name is determined by the Issuer.

   This field MUST be non-empty.

3.6.  Valid From

   The starting time at which point the certificate is valid.  In this
   profile the "Valid From" time is to be no earlier than the time of
   certificate generation.  As per Section 4.1.2.5 of [RFC3280],
   Certificate Authorities (CAs) conforming to this profile MUST always
   encode the certificate's "Valid From" date through the year 2049 as



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   UTCTime, and dates in 2050 or later MUST be encoded as
   GeneralizedTime.  These two time formats are defined in [RFC3280].

3.7.  Valid To

   The Valid To time is the date and time at which point in time the
   certificate's validity ends.  It represents the anticipated lifetime
   of the resource allocation / assignment arrangement between the
   Issuer and the Subject.  As per Section 4.1.2.5 of [RFC3280], CAs
   conforming to this profile MUST always encode the certificate's
   "Valid To" date through the year 2049 as UTCTime, and dates in 2050
   or later MUST be encoded as GeneralizedTime.  These two time formats
   are defined in [RFC3280].

3.8.  Subject Public Key Info

   This field specifies the subject's public key and the algorithm with
   which the key is used.  The public key algorithm MUST be RSA, and
   thus the OID for the algorithm is 1.2.840.113549.1.1.1.  A minimum
   key size of 1024 bits is mandated in this profile.  Regional Registry
   CAs MUST use a key size of 2048 bits.

   [Note - not for publication.  One alternative option is to specify
   "no less than 2048 bits" and allow for longer key sizes.  On the
   other hand it may be preferable to move to EC-DSA instead of RSA, in
   which case allowing for the option of longer RSA key sizes may be
   considered inappropriate.]

3.9.  Resource Certificate Version 3 Extension Fields

   As noted in Section 4.2 of [RFC3280], each extension in a 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 [RFC3280].

   The following X.509 V3 extensions MUST be present in a conforming
   Resource Certificate.

3.9.1.  Basic Constraints

   The basic constraints extension identifies whether the subject of the
   certificate is a CA and the maximum depth of valid certification
   paths that include this certificate.

   The Issuer determines whether the cA boolean is set.  If this bit is
   set, then it indicates that the Subject is allowed to issue resources
   certificates within this overall framework (i.e. the subject is



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   permitted be a CA).

   The Path Length Constraint is not specified in this profile and MUST
   NOT be present.

   The Basic Constraints extension field is a critical extension in the
   Resource Certificate profile, and MUST be present.

   [note - not for publication.  It is unclear whether the CA bit should
   be set on in all cases.

3.9.2.  Subject Key Identifier

   The subject key identifier extension provides a means of identifying
   certificates that contain a particular public key.  To facilitate
   certification path construction, this extension MUST appear in all
   Resource Certificates.  This extension is non-critical.

   The value of the subject key identifier MUST be the value placed in
   the key identifier field of the Authority Key Identifier extension of
   certificates issued by the subject of this certificate.

   The Key Identifier used here 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[RFC3280].

3.9.3.  Authority Key Identifier

   The subject key identifier extension provides a means of identifying
   certificates that are signed by a particular issuer's private key, by
   providing a hash value of the corresponding Issuer's public key.  To
   facilitate path construction, this extension MUST appear in all
   Resource Certificates.  The keyIdentifier subfield MUST be present.
   The authorityCertIssuer and authorityCertSerialNumber subfields MAY
   be present.  This extension is non-critical.

   The Key Identifier used here 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 [RFC3280].

3.9.4.  Key Usage

   This describes the purpose of the certificate.  This is a critical
   extension, and it MUST be present.

   In certificates issued to CAs only the keyCertSign and CRLSign bits
   are set to TRUE.  In end-entity certificates the digitialSignature
   bit MUST be set and MUST be the only bit set to TRUE.



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3.9.5.  CRL Distribution Points

   This field (CRLDP) identifies the location(s) of the CRL(s)
   associated with certificates issued by this Issuer.  This profile
   uses the URI form of object identification.  The preferred URI access
   mechanism is a single "rsync" URL that references a single inclusive
   CRL for each issuer.

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

   The distributionPoint MUST contain general names, and MUST NOT
   contain a nameRelativeToCRLIssuer.  The type of the general name MUST
   be of type URI.  Furthermore, as the scope of the CRL is all
   certificates issued by this issuer, the sequence of distributionPoint
   values MUST contain only a single DistributionPointName set.  The
   DistributionPointName set MAY contain more than one URI value.  An
   rsync URI MUST be present in the DistributionPointName set.

   This extension MUST be present and it is non-critical.

   [NOTE - not for publication.  The reason for the specification of an
   RSYNC URI as a MUST in this profile is to ensure that relying parties
   who wish to maintain a local copy of a synchronized repository are
   not forced to maintain a retrieval capability using a potentially
   unbounded set of URI types.  The profile is attempting to ensure that
   rsync should be all that is required to perform a repository
   synchronization operation.  A more restrictive potential condition
   here (and also in the SIA and AIA extensions) is that one and only
   one RSYNC URI is permitted.  This would reduce some of the potential
   variations in certificates and also stress that certificate access
   and use by relying parties is critically dependent on RSYNC access,
   and that other forms of access are not necessarily available to
   relying parties.]

3.9.6.  Authority Information Access

   This field (AIA) identifies the location of all certificates that are
   issued by this Issuer that are signed with the Issuer's private key
   that signed this certificate.  This profile uses a URI form of object
   identification.  The preferred URI access mechanisms is "rsync", and
   an rsync URI MUST be specified with an accessMethod value of id-ad-
   caIssuers.  Other access method URIs MAY also be included in the
   value sequence of this extension.

   This field MUST be present, and is non-critical.



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   [Note - not for publication rfc3280 defines only two OIDs for the
   access method, id-ad-caIssuers and id-ad-ocsp.  It would appear that
   id-ad-ocsp is not relevant here in that OCSP is not included as part
   of the resource certificate profile - which leaves id-ad-caIssuers.
   The text in 4.2.2.1 of RFC3280 notes that: "the id-ad-caIssuers OID
   is used when the additional information lists CAs that have issued
   certificates superior to the CA that issued the certificate
   containing this extension.  The referenced CA issuers description is
   intended to aid certificate users in the selection of a certification
   path that terminates at a point trusted by the certificate user"
   However there is no intention to require that such a list be included
   in this subfield in this profile.  The question is: What accessMethod
   OID should be used here in the Access Description?]

3.9.7.  Subject Information Access

   This field (SIA) identifies the location of information and services
   relating to the subject of the certificate in which the SIA extension
   appears that relate to the subject public key that is certified in
   this certificate.  Where the Subject is a CA for Resource
   Certificates this information and service collection will include all
   current valid certificates that have been issued by this subject that
   are signed with the subject's corresponding private key.  This
   profile uses a URI form of location identification.  The preferred
   URI access mechanism is "rsync", and an rsync URI SHOULD be
   specified, with an access method value of id-ad-caRepository when the
   subject of the certificate is a CA.  Other access method URIs MAY
   also be included in the value sequence of this extension.

   This field MUST be present when the subject is a CA, and is non-
   critical.  Where the subject is not a CA this field MUST NOT be
   present.

   [Note - not for publication.  RFC3280 defines only two OIDs for the
   access method, id-ad-caRepository and id-ad-timeStamping, with the
   difference being whether the subject is a CA or not.  The access
   method id-ad-caRepository appears to be appropriate where the subject
   is a CA.  Where the subject is NOT a CA would it be useful to have
   the SIA extension point to where the subject stores digital objects
   that have been signed by the subject?  If this were considered to be
   desirable, then the id-ad-timeStamping appears to be inappropriate in
   this context.  The general question is: What accessMethod OID should
   be used here in the Access Description?  The approach currently used
   in this draft is that SIA should only be present for CAs and must be
   absent in the case of End Entity certificates.]






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3.9.8.  Certificate Policies

   This extension MUST reference the Resource Certificate Policy, using
   the OID Policy Identifier value of "1.3.6.1.5.5.7.14.2".  This field
   MUST be present and MUST contain only this value for Resource
   Certificates.

   PolicyQualifiers MUST NOT be used in this profile.

   This extension MUST be present and it is critical.

3.9.9.  Subject Alternate Name

   This is an optional extension, and MAY contain an X.501 Name as
   supplied by the subject in the Certificate Request or as assigned by
   the Issuer CA.

3.9.10.  IP Resources

   This field contains the list of IP address resources as per
   [RFC3779].  The value may specify the "inherit" element for a
   particular AFI value and an optional SAFI value.  All Resource
   Certificates MUST include an IP Resources extension, an AS Resources
   extension, or both extensions.

   This extension, if present, MUST be marked critical.

3.9.11.  AS Resources

   This field contains the list of AS number resources as per [RFC3779],
   or may specify the "inherit" element.  All Resource Certificates MUST
   include an IP Resources extension, an AS Resources extension, or both
   extensions.  RDI values are NOT supported in this profile and MUST
   NOT be used.

   This extension, if present, MUST be marked critical.


4.  Resource Certificate Revocation List Profile

   Each Resource CA MUST issue a version 2Certificate Revocation List
   (CRL), consistent with [RFC3280].  The CRL issuer is the CA, and no
   indirect CRLs are supported in this profile.  The scope of the CRL
   MUST be "all certificates issued by this CA".  The contents of the
   CRL are a list of all unexpired certificates issued by the CA that
   have been revoked by the CA.

   An entry MUST NOT be removed from the CRL until it appears on one



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   regularly scheduled CRL issued beyond the revoked certificate's
   validity period.

   This profile does not allow issuance of Delta CRLs.

   The profile does not allow the issuance of multiple current CRLs with
   different scope by a single CA.

   No CRL fields other than those listed below are allowed in CRLs
   issued under this profile.  Unless otherwise indicated, these fields
   MUST be present in the CRL.  Where two or more CRLs issued by a
   single CA are present in a certificate repository, the CRL with the
   highest value of the "CRL Number" field supersedes all other extant
   CRLs issued by this CA..

4.1.  Version

   Resource Certificate Revocation Lists are Version 2 certificates (the
   integer value of this field is 1).

4.2.  Issuer Name

   The value of this field is the X.501 name of the issuing CA who is
   also the signer of the CRL, and is identical to the Issuer name in
   the Resource Certificates.

4.3.  This Update

   This is the date and time that this CRL was issued.  The value of
   this field MUST be encoded as UTCTime for dates through the year
   2049, and MUST be encoded as GeneralizedTime for dates in the year
   2050 or later.

4.4.  Next Update

   This is the date and time by which the next CRL will be issued.  The
   value of this field MUST be encoded as UTCTime for dates through the
   year 2049, and MUST be encoded as GeneralizedTime for dates in the
   year 2050 or later.

4.5.  Signature

   This field contains the algorithm used to sign this CRL.  The
   signature algorithm MUST be SHA-256 with RSA.  This field MUST be
   present.






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4.6.  Revoked Certificate List

   When there are no revoked certificates, then the revoked certificate
   list MUST be absent.

   For each revoked resource certificate ONLY the following fields MUST
   be present.  No CRL entry extensions are supported in this profile.

4.6.1.  Serial Number

   The serial number of the revoked certificate.

4.6.2.  Revocation Date

   The time the certificate was revoked.  This time SHOULD NOT be a
   future date.  The value of this field MUST be encoded as UTCTime for
   dates through the year 2049, and MUST be encoded as GeneralizedTime
   for dates in the year 2050 or later.

4.7.  CRL Extensions

   The X.509 v2 CRL format allows extensions to be placed in a CRL.  The
   following extensions are supported in this profile, and MUST be
   present in a CRL.

4.7.1.  Authority Key Identifier

   The authority key identifier extension provides a means of
   identifying the public key corresponding to the private key used to
   sign a CRL.  Conforming CRL issuers MUST use the key identifier
   method.  The syntax for this CRL extension is defined in section
   4.2.1.1 of [RFC3280].

   This extension is non-critical.

4.7.2.  CRL Number

   The CRL Number extension conveys a monotonically increasing sequence
   number for a given CA.  This extension allows users to easily
   determine when a particular CRL supersedes another CRL.  The higher
   CRL Number value supersedes all other CRLs issued by the CA within
   the scope of this profile.

   This extension is non-critical.







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5.  Resource Certificate Request Profile

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

   [Note - not for publication.  RFC2986 references PKCS #10:
   Certification Request Syntax Specification, Version 1.7.  Given the
   relative wide support of CMC, the extension of PKCS#10 that is
   roughly equivalent to CMP, then it would appear that a CMC profile
   should also be included here.  It is unclear at this point whether a
   PCKS#10 profile is also necessary in this profile.]

   This request may be conveyed to the CA via a Registration Authority
   (RA), acting under the direction of a Subject.

   [Note - not for publication: There are no profile-based
   qualifications regarding Proof-of-Possession.  This may be refined in
   subsequent iterations of this draft.]

5.1.  Resource Certificate Request Template Fields


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

   Version
      This field MAY be absent, or MAY specify the request of a Version
      3 Certificate.

   SerialNumber
      As per [RFC4211], this field is assigned by the CA and MUST be
      omitted in this profile.

   SigningAlgorithm
      As per [RFC4211], this field is assigned by the CA and MUST be
      omitted in this profile.

   Issuer
      This field is assigned by the CA and MUST be omitted in this
      profile.








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   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  As the subject name is assigned by the CA, this field MAY be
      omitted, in which case the subject name will be generated by the
      CA.  If specified, the CA SHOULD consider this as the subject's
      suggestion, but the CA is NOT bound to honour this suggestion.

   PublicKey
      This field MUST be present.

   This profile applies the following additional constraints to X509 v3
   Certificate extension fields that may appear in a Certificate
   Request:

   BasicConstraints
      If this is omitted then this field is assigned by the CA.

      The Path Length Constraint is not supported in this Resource
      Certificate Profile, and this field MUST be omitted in this
      profile.

      The CA MAY honour the SubjectType CA bit set to on.  If this bit
      is set, then it indicates that the Subject is allowed to issue
      resources certificates within this overall framework.

      The CA MAY honour the SubjectType CA bit set of off (End Entity
      certificate request).

      [Note - not for publication.  There are some potential variants on
      this model, where the CA bit may be considered as being set in all
      circumstances.  For example, if the generation of signed resource
      objects, such as routing origination authorities requires the
      generation of special purpose resource certificates whose validity
      dates are implicitly the validity dates of the associated
      authority, then the subject needs to be able to issue certificates
      - i.e. there is a CA requirement.  In this version of the draft
      this is left as a subject suggestion in the request that the CA
      may, or may not, honor in the issued certificate.  In this model
      all the entities are CAs, except for the users of ROA signing
      shadow certs.  In both cases, the CA knows the intended purpose
      (i.e. issue to others: CA, issue shadow to yourself: non-CA). ]






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   SubjectKeyIdentifier
      This field is assigned by the CA and MUST be omitted in this
      profile.

   AuthorityKeyIdentifier
      This field is assigned by the CA and MUST be omitted in this
      profile.

   KeyUsage
      The CA MAY honor KeyUsage extensions of CertificateSigning and
      CRLSigning if present, as long as this is consistent with the
      BasicConstraints SubjectType subfield, when specified.

   CRLDistributionPoints
      This field MAY be honoured by the CA on the condition that the CA
      issues a certificate with the BasicConstraints SubjectType CA bit
      set and the KeyUsage set to CertificateSigning and CRLSigning.

      If specified, this field contains a sequence of URIs that
      references a CRL that will be published by the subject for
      subordinate certificates.  This sequence MUST include a rsync URI.
      This field MAY be honoured by the CA if present.

      If this field is omitted and KeyUsage is set to CertificateSigning
      then the CA MUST generate a CRLDistributionPoint URL based on out-
      of-band information that has been passed between the CA and the
      requester.

      [Note - not for publication.  The issue of where and how to
      specify where the subject will publish the CRL if the CA bit is
      set and honored by the issuer is described here as information
      that is either provided in this field in the certificate request
      or provided via an "out-of-band" exchange.  An alternative is to
      say that this field MUST be provided if the CA bit is set in the
      request.]

   AuthorityInformationAccess
      This field is assigned by the CA and MUST be omitted in this
      profile.

   SubjectInformationAccess
      This field MAY be honoured by the CA on the condition that the CA
      issues a certificate with the BasicConstraints SubjectType CA bit
      set and the KeyUsage set to CertificateSigning and CRLSigning.







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      If specified, this field contains a URI of the form of a single
      rsync URL that references a single publication point that will be
      used by the subject for all certificates that published by the
      subject for subordinate certificates, and MUST be honoured by the
      CA.

      If this field is omitted and KeyUsage is set to CertificateSigning
      then the CA MUST generate a SIA URL based on out-of-band
      information that has been passed between the CA and the requester.

      [Note not for publication - the same considerations with respect
      to the CRL DistributionPoints apply to this field as well. i.e. if
      this field is missing than it is also an option for the Issuer to
      deny the request and not issue a certificate if the issued
      certificate was to have the CA bit set.]

   CertificatePolicies
      This field is assigned by the CA and MUST be omitted in this
      profile.

   SubjectAlternateName
      This field MAY be present, and the CA MAY use this as the
      SubjectAltName in the issued Certificate.

   IPResources
      This field is assigned by the CA and MUST be omitted in this
      profile.

   ASResources
      This field is assigned by the CA and MUST be omitted in this
      profile.

   With the exception of the publicKey field, the CA is permitted to
   alter any requested field.

5.2.  Resource Certificate Request Control Fields

   The following control fields are supported in this profile:

   Authenticator Control
      It is noted that the intended model of authentication of the
      subject in a long term one, and the advice as offered in [RFC4211]
      is that the Authenticator Control field be used.








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      [Note - not for publication: The method of generation and
      authentication of this field is to be specified.  The desirable
      properties include the ability to validate the subject and the
      authenticity of the provided public key.]

   Resource Class
      The profile defines an additional control for Resource Certificate
      Requests, namely a Resource Class control.
      The Subject MUST specify a Resource Class value as specified by
      the CA to which the request refers.  The CA will issue a
      certificate with the IPAddress and AS Number resources that match
      the subject's right-of-use of these resources with the class of
      resources specified by the Resource Class control value.

      [Note - not for publication: This specification of the resource
      class is related the various forms of resource allocation which
      imply that an entity may be the holder of resources with differing
      validation dates and differing validation paths, even when the
      entity is the recipient of resources allocated from a single
      'upstream' issuing registry.  Due to this consideration it may not
      be possible to issue a single certificate with an all-encompassing
      resource set.  Alternatively it is possible to define a structure
      where there is no Resource Class specified and the issuer issues a
      set of spanning certificates for all resources held by the subject
      (i.e. all resources that fall under the subject's "right-of-use")]


6.  Resource Certificate Validation

   This section describes the Resource Certificate validation procedure.
   This refines the generic procedure described in [RFC3280]:

   To meet this goal, the 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}, the certificate was valid at the time
       in question.






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6.1.  Trust Anchors for Resource Certificates

   The trust model used in the resource certificate framework in the
   context of validation of assertions of public number resources in
   public-use contexts is a top-down delegated CA model that mirrors the
   delegation of resources from a registry distribution point to the
   entities that are the direct recipients of these resources.  Within
   the trust model these recipient entities may, in turn, operate a
   registry and perform further allocations or assignments.  This is a
   strict hierarchy, in that any number resource and a corresponding
   recipient entity has only one 'parent' issuing registry for that
   number resource (i.e. there is always a unique parent entity for any
   resource and corresponding entity), and that the issuing registry is
   not a direct or indirect subordinate recipient entity of the
   recipient entity in question (i.e. no loops in the hierarchy).  The
   only exception to the "no loop" condition are the nominated trust
   anchors, where a self-signed certificate is issued.

   At the time of preparing this draft there are proposed to be multiple
   roots of this public number resource hierarchy, corresponding to
   multiple trust anchors.  These trust anchors are the self-signed
   certificates that are issued by the Regional Internet Registries.
   Each self-signed certificate issued by a RIR contains a resource set
   that describes those resources where the RIR is administratively
   responsible.  There MUST NOT be overlap of resources in the IP
   resource extensions across the collection of RIR self-signed
   certificates.  This implies that a validation path for any valid
   certificate is unique, in the sense that the path will terminate with
   a single trust anchor.

   Cross-certification of these trust anchors, where one trust anchor
   entity issues a certificate with a subject of another trust anchor is
   not seen as providing any further substance to the integrity or ease
   of validation in this trust model, so cross-certification is not used
   in the trust anchor structure for this Resource Certificate
   framework.

   The adoption of a single trust anchor as a unique distinguished root
   of this certificate hierarchy is a potential future option here, and
   within the proposed framework some care has been taken not to
   preclude the potential for a single distinguished root for this
   certificate framework that could issue a certificate to each RIR with
   a resource extension that matches the resource sets that fall under
   the administrative responsibility of each RIR.







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6.2.  Resource Extension Validation

   The IP resource extension definition [RFC3779] defines a critical
   extensions for Internet number resources.  These are ASN.1 encoded
   representations of the IPv4 and IPv6 address range (either as a
   prefix/length, or start-end pair) and the 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 IP address or AS number contiguous 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 IP address or AS number contiguous ranges, A and B,
      A is "equal" to B if range A describes precisely the same
      collection of IP addresses or AS numbers as described by range B.
      The definition of "inheritance" in [RFC3779]is equivalent to this
      "equality" comparison.

   Validation of a certificate's resource extension in the context of an
   ordered certification path of {1,2, ... , n} where '1'is a trust
   anchor and 'n' is the target certificate, implies that each of the
   contiguous resource sets of IP addresses and AS Numbers described in
   certificate x, for 'x' is greater than , are more specific or equal
   to the resources described in certificate x-1.

6.3.  Resource Certificate Path Validation

   Validation of signed resource data using a target resource
   certificate consists of assembling an ordered sequence (or
   'Certificate Path') of certificates ({1,2,...n} where '1' is a trust
   anchor, and 'n' is the target certificate) verifying that all of the
   following conditions hold:

   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 and
       contains field values as specified in this profile for all field
       values that MUST be present.



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   4.  No field value that MUST NOT be present is present in the
       certificate.

   5.  The Issuer has not revoked the certificate by placing the
       certificate's serial number on the Issuer's current Certificate
       Revocation List, and the CRL is itself valid.

   6.  That the resource extension data is equal to or more specific
       than the resource extension data contained in a valid certificate
       where this Issuer is the Subject (the previous certificate in the
       ordered sequence)

   7.  The Certificate Path originates at a trust anchor, and there
       exists a signing chain across the Certificate Path where the
       Subject of Certificate x in the Certificate Path matches the
       Issuer in Certificate x+1 in the Certificate Path.

   Validation of a certificate may perform these tests in any chosen
   order.

   A Resource Certificate may have a number of potential parent
   certificates, where a potential parent certificate is one where the
   subject name matches the issuer name of the resource certificate.  A
   candidate parent certificate is any member of the parent certificate
   set where the resource extension validity constraint is satisfied,
   and a valid candidate parent certificate is any candidate parent
   certificate that also matches validity conditions 1 through 6.  A
   valid parent certificate is a valid candidate parent certificate that
   also matches validity condition 7.

   Certificates and CRLs used in this process may be found on a single
   repository, maintained by a regular top-down walk from the Root Trust
   Anchors via Issuer certificates and their SIA fields as forward
   pointers, plus the CRLDP.  Alternatively, validation may be performed
   using a bottom-up process with on-line certificate access using the
   AIA and CRLDP pointers to guide the certificate retrieval process.

   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 DOS attack on a certificate validator.
   Some further heuristics may be required to halt the validation
   process in order to avoid some of the issues associated with attempts
   to validate such structures.  It is suggested that implementations of
   Resource Certificate validation MAY halt with a validation failure if
   the certificate path length exceeds a pre-determined configuration
   parameter.

   In the context of Resource Certificates that are generated in respect



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   of public resources and with the framework of the associated resource
   distribution process, it is suggested that this configuration
   parameter of maximum certificate path length be set to a value of
   100.  (There is no particular reason for suggesting this value other
   than the observation that it appears to be comfortably longer than
   any real distribution chain for public number resources, without
   being too long so as to pose potential DOS concerns for relying
   parties performing a validation operation.)


7.  Security Considerations

   [to be completed]


8.  IANA Considerations

   [An OID for a resource class option in a certificate request may need
   to be defined.]


9.  Acknowledgements

   The authors would like to acknowledge the valued contributions from
   Stephen Kent, Robert Kisteleki, Randy Bush, Russ Housley, Ricardo
   Patara and Rob Austein in the preparation and subsequent review of
   this document.


10.  Normative References

   [RFC0791]  Postel, J., "Internet Protocol", STD 5, RFC 791,
              September 1981.

   [RFC2050]  Hubbard, K., Kosters, M., Conrad, D., Karrenberg, D., and
              J. Postel, "INTERNET REGISTRY IP ALLOCATION GUIDELINES",
              BCP 12, RFC 2050, November 1996.

   [RFC3280]  Housley, R., Polk, W., Ford, W., and D. Solo, "Internet
              X.509 Public Key Infrastructure Certificate and
              Certificate Revocation List (CRL) Profile", RFC 3280,
              April 2002.

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

   [RFC4055]  Schaad, J., Kaliski, B., and R. Housley, "Additional
              Algorithms and Identifiers for RSA Cryptography for use in



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              the Internet X.509 Public Key Infrastructure Certificate
              and Certificate Revocation List (CRL) Profile", RFC 4055,
              June 2005.

   [RFC4158]  Cooper, M., Dzambasow, Y., Hesse, P., Joseph, S., and R.
              Nicholas, "Internet X.509 Public Key Infrastructure:
              Certification Path Building", RFC 4158, September 2005.

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

   [RFC4291]  Hinden, R. and S. Deering, "IP Version 6 Addressing
              Architecture", RFC 4291, February 2006.


Appendix A.  Example Resource Certificate

   The following is an example Resource Certificate.

   Certificate Name: UDkyh1nUjIjk5_WpdkZMh3KuvYo-25f7.crt

   Data:
     Version: 3
     Serial:  9719 (0x25f7)
     Signature Algorithm:
              Hash: SHA256, Encryption: RSA
     Issuer:  CN=APNIC-AP-IANA
     Validity:
              Not Before: Fri May 12 05:37:43 2006 GMT
              Not After:  Thu Aug 10 05:37:43 2006 GMT
     Subject: CN=FC9B85ADDF5B
     Subject Public Key Info:
              Public Key Algorithm: rsaEncryption
              RSA Public Key: (1024 bit)
              Modulus (1024 bit):
                   00:f2:e5:63:d6:e3:89:45:47:02:13:90:b7:e5:39:
                   a3:f0:8c:3b:27:0d:d1:90:92:46:9b:45:d0:52:34:
                   f1:7c:c7:34:9f:be:d0:41:18:ab:35:43:62:89:2e:
                   3e:32:ab:01:e2:86:76:2a:44:83:49:4c:83:02:b4:
                   0c:2a:b0:b2:82:c6:35:24:7b:16:7a:35:42:36:15:
                   18:50:fe:8b:7f:c9:04:18:69:6b:ed:59:0d:61:ea:
                   20:ef:cd:19:30:9f:ce:b8:4a:f5:fb:ad:81:42:ab:
                   57:72:0c:47:b0:d8:30:c0:0c:5b:52:dc:aa:94:95:
                   3e:fe:44:ac:d5:b0:f4:d5:cb
              Exponent: 65537 (0x10001)
     X509v3 extensions:
       Basic Constraints:



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              CA:TRUE
       Subject Key Identifier:
              keyid: 50:39:32:87:59:D4:8C:88:E4:E7:F5:A9:
                     76:46:4C:87:72:AE:BD:8A
       Authority Key Identifier:
              keyid: 19:54:CD:F2:81:C6:4E:31:09:6D:3A:15:
                     E6:88:39:30:21:A6:56:73
       Key Usage: critical
              Certificate Sign, CRL Sign
       CRL Distribution Points:
              URI:rsync://rsync.apnic.net/repository/
                         pvpjvwUeQix2e54X8fGbhmdYMo0/
                         GVTN8oHGTjEJbToV5og5MCGmVnM/
                         GVTN8oHGTjEJbToV5og5MCGmVnM.crl
       Authority Information Access:
               CA Issuers - URI:rsync://rsync.apnic.net/repository/
                                       pvpjvwUeQix2e54X8fGbhmdYMo0/
                                       GVTN8oHGTjEJbToV5og5MCGmVnM
       Subject Information Access:
               CA Repository - URI:rsync://rsync.apnic.net/repository/
                                      pvpjvwUeQix2e54X8fGbhmdYMo0/
                                      GVTN8oHGTjEJbToV5og5MCGmVnM/
                                      UDkyh1nUjIjk5_WpdkZMh3KuvYo
       Certificate Policies: critical
               Policy: 1.3.6.1.5.5.7.14.2
       ipAddrBlock: critical
               192.0.0.0/24
       autonomousSysNum: critical
               64512
       Subject Alternative Name:
               DirName:/CN=<subject_supplied_string>

     Signature:
               72:27:9c:bc:a8:7f:c0:f0:27:62:a1:1f:55:b3:c7:b1:31:c9:fc:
               42:84:71:30:3b:0d:c0:d6:ad:79:b1:f6:1d:14:e8:f3:0f:f3:dd:
               40:3d:ae:28:a6:33:96:b6:d3:7d:d2:f3:ac:d3:8e:d4:2e:ad:ab:
               71:4d:05:74:20:ed:bc:e3:bd:85:7f:af:8b:70:3e:b8:90:b6:2d:
               a5:e3:9d:2a:c8:a9:9b:73:3c:03:43:d2:b8:d2:4e:68:34:eb:db:
               3c:44:eb:eb:1e:3b:03:d9:3b:e0:64:a6:31:90:9b:2c:4a:26:8e:
               0e:36:4c:ee:c8:e9:29:6b:78:61:87:05:e2:f9


Appendix B.  Example Certificate Revocation List

   The following is an example Certificate Revocation List.






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   Certificate Name: GVTN8oHGTjEJbToV5og5MCGmVnM.crl

   Data:
     Version: 2
     Issuer:  CN=APNIC-AP-IANA
     Effective Date: Fri May 12 05:37:43 2006 GMT
     Next Update:    Fri May 26 05:37:43 2006 GMT
     Signature algorithn
              Hash: SHA256, Encryption: RSA
     CRL V2 Extensions:
       Authority Key Identifier:
         Keyid: 19:54:cd:f2:81:c6:4e:31:09:6d:3a:15:
                e6:88:39:30:21:a6:56:73
         Certificate Issuer:
                CN=APNIC-AP-IANA
         Certificate Serial Number: 1b
       CRL Number:  1097
     Revocation List:
       Revoked Certificates
         Serial Number: 0b
           Revocation Date: Mon May 8 05:10:19 2006 GMT
         Serial Number: 0c
           Revocation Date: Mon May 8 05:10:19 2006 GMT


Authors' Addresses

   Geoff Huston
   Asia Pacific Network Information Centre

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


   Robert Loomans
   Asia Pacific Network Information Centre

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


   George Michaelson
   Asia Pacific Network Information Centre

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





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Full Copyright Statement

   Copyright (C) The Internet Society (2006).

   This document is subject to the rights, licenses and restrictions
   contained in BCP 78, and except as set forth therein, the authors
   retain all their rights.

   This document and the information contained herein are provided on an
   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
   OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
   ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
   INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
   INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
   WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.


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   The IETF invites any interested party to bring to its attention any
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   this standard.  Please address the information to the IETF at
   ietf-ipr@ietf.org.


Acknowledgment

   Funding for the RFC Editor function is provided by the IETF
   Administrative Support Activity (IASA).





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