Network Working Group                                        K. Zeilenga
Request for Comments: 4523                           OpenLDAP Foundation
Obsoletes: 2252, 2256, 2587                                    June 2006
Category: Standards Track


            Lightweight Directory Access Protocol (LDAP)
              Schema Definitions for X.509 Certificates

Status of This Memo

  This document specifies an Internet standards track protocol for the
  Internet community, and requests discussion and suggestions for
  improvements.  Please refer to the current edition of the "Internet
  Official Protocol Standards" (STD 1) for the standardization state
  and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

  Copyright (C) The Internet Society (2006).

  Abstract

  This document describes schema for representing X.509 certificates,
  X.521 security information, and related elements in directories
  accessible using the Lightweight Directory Access Protocol (LDAP).
  The LDAP definitions for these X.509 and X.521 schema elements
  replace those provided in RFCs 2252 and 2256.

1.  Introduction

  This document provides LDAP [RFC4510] schema definitions [RFC4512]
  for a subset of elements specified in X.509 [X.509] and X.521
  [X.521], including attribute types for certificates, cross
  certificate pairs, and certificate revocation lists; matching rules
  to be used with these attribute types; and related object classes.
  LDAP syntax definitions are also provided for associated assertion
  and attribute values.

  As the semantics of these elements are as defined in X.509 and X.521,
  knowledge of X.509 and X.521 is necessary to make use of the LDAP
  schema definitions provided herein.

  This document, together with [RFC4510], obsoletes RFCs 2252 and 2256
  in their entirety.  The changes (in this document) made since RFC
  2252 and RFC 2256 include:

     -  addition of pkiUser, pkiCA, and deltaCRL classes;



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     -  update of attribute types to include equality matching rules in
        accordance with their X.500 specifications;

     -  addition of certificate, certificate pair, certificate list,
        and algorithm identifier matching rules; and

     -  addition of LDAP syntax for assertion syntaxes for these
        matching rules.

  This document obsoletes RFC 2587.  The X.509 schema descriptions for
  LDAPv2 [RFC1777] are Historic, as is LDAPv2 [RFC3494].

  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 BCP 14 [RFC2119].

  Schema definitions are provided using LDAP description formats
  [RFC4512].  Definitions provided here are formatted (line wrapped)
  for readability.

2.  Syntaxes

  This section describes various syntaxes used in LDAP to transfer
  certificates and related data types.

2.1.  Certificate

     ( 1.3.6.1.4.1.1466.115.121.1.8 DESC 'X.509 Certificate' )

  A value of this syntax is an X.509 Certificate [X.509, clause 7].

  Due to changes made to the definition of a Certificate through time,
  no LDAP-specific encoding is defined for this syntax.  Values of this
  syntax SHOULD be encoded using Distinguished Encoding Rules (DER)
  [X.690] and MUST only be transferred using the ;binary transfer
  option [RFC4522]; that is, by requesting and returning values using
  attribute descriptions such as "userCertificate;binary".

  As values of this syntax contain digitally signed data, values of
  this syntax and the form of each value MUST be preserved as
  presented.

2.2.  CertificateList

     ( 1.3.6.1.4.1.1466.115.121.1.9 DESC 'X.509 Certificate List' )

  A value of this syntax is an X.509 CertificateList [X.509, clause
  7.3].



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  Due to changes made to the definition of a CertificateList through
  time, no LDAP-specific encoding is defined for this syntax.  Values
  of this syntax SHOULD be encoded using DER [X.690] and MUST only be
  transferred using the ;binary transfer option [RFC4522]; that is, by
  requesting and returning values using attribute descriptions such as
  "certificateRevocationList;binary".

  As values of this syntax contain digitally signed data, values of
  this syntax and the form of each value MUST be preserved as
  presented.

2.3.  CertificatePair

     ( 1.3.6.1.4.1.1466.115.121.1.10 DESC 'X.509 Certificate Pair' )

  A value of this syntax is an X.509 CertificatePair [X.509, clause
  11.2.3].

  Due to changes made to the definition of an X.509 CertificatePair
  through time, no LDAP-specific encoding is defined for this syntax.
  Values of this syntax SHOULD be encoded using DER [X.690] and MUST
  only be transferred using the ;binary transfer option [RFC4522]; that
  is, by requesting and returning values using attribute descriptions
  such as "crossCertificatePair;binary".

  As values of this syntax contain digitally signed data, values of
  this syntax and the form of each value MUST be preserved as
  presented.

2.4.  SupportedAlgorithm

     ( 1.3.6.1.4.1.1466.115.121.1.49
          DESC 'X.509 Supported Algorithm' )

  A value of this syntax is an X.509 SupportedAlgorithm [X.509, clause
  11.2.7].

  Due to changes made to the definition of an X.509 SupportedAlgorithm
  through time, no LDAP-specific encoding is defined for this syntax.
  Values of this syntax SHOULD be encoded using DER [X.690] and MUST
  only be transferred using the ;binary transfer option [RFC4522]; that
  is, by requesting and returning values using attribute descriptions
  such as "supportedAlgorithms;binary".

  As values of this syntax contain digitally signed data, values of
  this syntax and the form of the value MUST be preserved as presented.





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2.5.  CertificateExactAssertion

     ( 1.3.6.1.1.15.1 DESC 'X.509 Certificate Exact Assertion' )

  A value of this syntax is an X.509 CertificateExactAssertion [X.509,
  clause 11.3.1].  Values of this syntax MUST be encoded using the
  Generic String Encoding Rules (GSER) [RFC3641].  Appendix A.1
  provides an equivalent Augmented Backus-Naur Form (ABNF) [RFC4234]
  grammar for this syntax.

2.6.  CertificateAssertion

     ( 1.3.6.1.1.15.2 DESC 'X.509 Certificate Assertion' )

  A value of this syntax is an X.509 CertificateAssertion [X.509,
  clause 11.3.2].  Values of this syntax MUST be encoded using GSER
  [RFC3641].  Appendix A.2 provides an equivalent ABNF [RFC4234]
  grammar for this syntax.

2.7.  CertificatePairExactAssertion

     ( 1.3.6.1.1.15.3
          DESC 'X.509 Certificate Pair Exact Assertion' )

  A value of this syntax is an X.509 CertificatePairExactAssertion
  [X.509, clause 11.3.3].  Values of this syntax MUST be encoded using
  GSER [RFC3641].  Appendix A.3 provides an equivalent ABNF [RFC4234]
  grammar for this syntax.

2.8.  CertificatePairAssertion

     ( 1.3.6.1.1.15.4 DESC 'X.509 Certificate Pair Assertion' )

  A value of this syntax is an X.509 CertificatePairAssertion [X.509,
  clause 11.3.4].  Values of this syntax MUST be encoded using GSER
  [RFC3641].  Appendix A.4 provides an equivalent ABNF [RFC4234]
  grammar for this syntax.

2.9.  CertificateListExactAssertion

     ( 1.3.6.1.1.15.5
          DESC 'X.509 Certificate List Exact Assertion' )

  A value of this syntax is an X.509 CertificateListExactAssertion
  [X.509, clause 11.3.5].  Values of this syntax MUST be encoded using
  GSER [RFC3641].  Appendix A.5 provides an equivalent ABNF grammar for
  this syntax.




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2.10.  CertificateListAssertion

     ( 1.3.6.1.1.15.6 DESC 'X.509 Certificate List Assertion' )

  A value of this syntax is an X.509 CertificateListAssertion [X.509,
  clause 11.3.6].  Values of this syntax MUST be encoded using GSER
  [RFC3641].  Appendix A.6 provides an equivalent ABNF [RFC4234]
  grammar for this syntax.

2.11.  AlgorithmIdentifier

     ( 1.3.6.1.1.15.7 DESC 'X.509 Algorithm Identifier' )

  A value of this syntax is an X.509 AlgorithmIdentifier [X.509, Clause
  7].  Values of this syntax MUST be encoded using GSER [RFC3641].

  Appendix A.7 provides an equivalent ABNF [RFC4234] grammar for this
  syntax.

3.  Matching Rules

  This section introduces a set of certificate and related matching
  rules for use in LDAP.  These rules are intended to act in accordance
  with their X.500 counterparts.

3.1.  certificateExactMatch

  The certificateExactMatch matching rule compares the presented
  certificate exact assertion value with an attribute value of the
  certificate syntax as described in clause 11.3.1 of [X.509].

     ( 2.5.13.34 NAME 'certificateExactMatch'
          DESC 'X.509 Certificate Exact Match'
          SYNTAX 1.3.6.1.1.15.1 )

3.2.  certificateMatch

  The certificateMatch matching rule compares the presented certificate
  assertion value with an attribute value of the certificate syntax as
  described in clause 11.3.2 of [X.509].

     ( 2.5.13.35 NAME 'certificateMatch'
          DESC 'X.509 Certificate Match'
          SYNTAX 1.3.6.1.1.15.2 )







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3.3.  certificatePairExactMatch

  The certificatePairExactMatch matching rule compares the presented
  certificate pair exact assertion value with an attribute value of the
  certificate pair syntax as described in clause 11.3.3 of [X.509].

     ( 2.5.13.36 NAME 'certificatePairExactMatch'
          DESC 'X.509 Certificate Pair Exact Match'
          SYNTAX 1.3.6.1.1.15.3 )

3.4.  certificatePairMatch

  The certificatePairMatch matching rule compares the presented
  certificate pair assertion value with an attribute value of the
  certificate pair syntax as described in clause 11.3.4 of [X.509].

     ( 2.5.13.37 NAME 'certificatePairMatch'
          DESC 'X.509 Certificate Pair Match'
          SYNTAX 1.3.6.1.1.15.4 )

3.5.  certificateListExactMatch

  The certificateListExactMatch matching rule compares the presented
  certificate list exact assertion value with an attribute value of the
  certificate pair syntax as described in clause 11.3.5 of [X.509].

     ( 2.5.13.38 NAME 'certificateListExactMatch'
          DESC 'X.509 Certificate List Exact Match'
          SYNTAX 1.3.6.1.1.15.5 )

3.6.  certificateListMatch

  The certificateListMatch matching rule compares the presented
  certificate list assertion value with an attribute value of the
  certificate pair syntax as described in clause 11.3.6 of [X.509].

     ( 2.5.13.39 NAME 'certificateListMatch'
          DESC 'X.509 Certificate List Match'
          SYNTAX 1.3.6.1.1.15.6 )












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3.7.  algorithmIdentifierMatch

  The algorithmIdentifierMatch mating rule compares a presented
  algorithm identifier with an attribute value of the supported
  algorithm as described in clause 11.3.7 of [X.509].

     ( 2.5.13.40 NAME 'algorithmIdentifier'
          DESC 'X.509 Algorithm Identifier Match'
          SYNTAX 1.3.6.1.1.15.7 )

4.  Attribute Types

  This section details a set of certificate and related attribute types
  for use in LDAP.

4.1.  userCertificate

  The userCertificate attribute holds the X.509 certificates issued to
  the user by one or more certificate authorities, as discussed in
  clause 11.2.1 of [X.509].

     ( 2.5.4.36 NAME 'userCertificate'
          DESC 'X.509 user certificate'
          EQUALITY certificateExactMatch
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.8 )

  As required by this attribute type's syntax, values of this attribute
  are requested and transferred using the attribute description
  "userCertificate;binary".

4.2.  cACertificate

  The cACertificate attribute holds the X.509 certificates issued to
  the certificate authority (CA), as discussed in clause 11.2.2 of
  [X.509].

     ( 2.5.4.37 NAME 'cACertificate'
          DESC 'X.509 CA certificate'
          EQUALITY certificateExactMatch
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.8 )

  As required by this attribute type's syntax, values of this attribute
  are requested and transferred using the attribute description
  "cACertificate;binary".







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4.3.  crossCertificatePair

  The crossCertificatePair attribute holds an X.509 certificate pair,
  as discussed in clause 11.2.3 of [X.509].

     ( 2.5.4.40 NAME 'crossCertificatePair'
          DESC 'X.509 cross certificate pair'
          EQUALITY certificatePairExactMatch
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.10 )

  As required by this attribute type's syntax, values of this attribute
  are requested and transferred using the attribute description
  "crossCertificatePair;binary".

4.4.  certificateRevocationList

  The certificateRevocationList attribute holds certificate lists, as
  discussed in 11.2.4 of [X.509].

     ( 2.5.4.39 NAME 'certificateRevocationList'
          DESC 'X.509 certificate revocation list'
          EQUALITY certificateListExactMatch
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.9 )

  As required by this attribute type's syntax, values of this attribute
  are requested and transferred using the attribute description
  "certificateRevocationList;binary".

4.5.  authorityRevocationList

  The authorityRevocationList attribute holds certificate lists, as
  discussed in 11.2.5 of [X.509].

     ( 2.5.4.38 NAME 'authorityRevocationList'
          DESC 'X.509 authority revocation list'
          EQUALITY certificateListExactMatch
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.9 )

  As required by this attribute type's syntax, values of this attribute
  are requested and transferred using the attribute description
  "authorityRevocationList;binary".










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4.6.  deltaRevocationList

  The deltaRevocationList attribute holds certificate lists, as
  discussed in 11.2.6 of [X.509].

     ( 2.5.4.53 NAME 'deltaRevocationList'
          DESC 'X.509 delta revocation list'
          EQUALITY certificateListExactMatch
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.9 )

  As required by this attribute type's syntax, values of this attribute
  MUST be requested and transferred using the attribute description
  "deltaRevocationList;binary".

4.7.  supportedAlgorithms

  The supportedAlgorithms attribute holds supported algorithms, as
  discussed in 11.2.7 of [X.509].

     ( 2.5.4.52 NAME 'supportedAlgorithms'
          DESC 'X.509 supported algorithms'
          EQUALITY algorithmIdentifierMatch
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.49 )

  As required by this attribute type's syntax, values of this attribute
  MUST be requested and transferred using the attribute description
  "supportedAlgorithms;binary".

5.  Object Classes

  This section details a set of certificate-related object classes for
  use in LDAP.

5.1.  pkiUser

  This object class is used in augment entries for objects that may be
  subject to certificates, as defined in clause 11.1.1 of [X.509].

     ( 2.5.6.21 NAME 'pkiUser'
          DESC 'X.509 PKI User'
          SUP top AUXILIARY
          MAY userCertificate )









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5.2.  pkiCA

  This object class is used to augment entries for objects that act as
  certificate authorities, as defined in clause 11.1.2 of [X.509]

     ( 2.5.6.22 NAME 'pkiCA'
          DESC 'X.509 PKI Certificate Authority'
          SUP top AUXILIARY
          MAY ( cACertificate $ certificateRevocationList $
               authorityRevocationList $ crossCertificatePair ) )

5.3.  cRLDistributionPoint

  This class is used to represent objects that act as CRL distribution
  points, as discussed in clause 11.1.3 of [X.509].

     ( 2.5.6.19 NAME 'cRLDistributionPoint'
          DESC 'X.509 CRL distribution point'
          SUP top STRUCTURAL
          MUST cn
          MAY ( certificateRevocationList $
               authorityRevocationList $ deltaRevocationList ) )

5.4.  deltaCRL

  The deltaCRL object class is used to augment entries to hold delta
  revocation lists, as discussed in clause 11.1.4 of [X.509].

     ( 2.5.6.23 NAME 'deltaCRL'
          DESC 'X.509 delta CRL'
          SUP top AUXILIARY
          MAY deltaRevocationList )

5.5.  strongAuthenticationUser

  This object class is used to augment entries for objects
  participating in certificate-based authentication, as defined in
  clause 6.15 of [X.521].  This object class is deprecated in favor of
  pkiUser.

     ( 2.5.6.15 NAME 'strongAuthenticationUser'
          DESC 'X.521 strong authentication user'
          SUP top AUXILIARY
          MUST userCertificate )







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5.6.  userSecurityInformation

  This object class is used to augment entries with needed additional
  associated security information, as defined in clause 6.16 of
  [X.521].

     ( 2.5.6.18 NAME 'userSecurityInformation'
          DESC 'X.521 user security information'
          SUP top AUXILIARY
          MAY ( supportedAlgorithms ) )

5.7.  certificationAuthority

  This object class is used to augment entries for objects that act as
  certificate authorities, as defined in clause 6.17 of [X.521].  This
  object class is deprecated in favor of pkiCA.

     ( 2.5.6.16 NAME 'certificationAuthority'
          DESC 'X.509 certificate authority'
          SUP top AUXILIARY
          MUST ( authorityRevocationList $
               certificateRevocationList $ cACertificate )
          MAY crossCertificatePair )

5.8.  certificationAuthority-V2

  This object class is used to augment entries for objects that act as
  certificate authorities, as defined in clause 6.18 of [X.521].  This
  object class is deprecated in favor of pkiCA.

     ( 2.5.6.16.2 NAME 'certificationAuthority-V2'
          DESC 'X.509 certificate authority, version 2'
          SUP certificationAuthority AUXILIARY
          MAY deltaRevocationList )

6.  Security Considerations

  General certificate considerations [RFC3280] apply to LDAP-aware
  certificate applications.  General LDAP security considerations
  [RFC4510] apply as well.

  While elements of certificate information are commonly signed, these
  signatures only protect the integrity of the signed information.  In
  the absence of data integrity protections in LDAP (or lower layer,
  e.g., IPsec), a server is not assured that client certificate request
  (or other request) was unaltered in transit.  Likewise, a client
  cannot be assured that the results of the query were unaltered in




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  transit.  Hence, it is generally recommended that implementations
  make use of authentication and data integrity services in LDAP
  [RFC4513][RFC4511].

7.  IANA Considerations

7.1.  Object Identifier Registration

  The IANA has registered an LDAP Object Identifier [RFC4520] for use
  in this technical specification.

     Subject: Request for LDAP OID Registration
     Person & email address to contact for further information:
         Kurt Zeilenga <[email protected]>
     Specification: RFC 4523
     Author/Change Controller: IESG
     Comments:
         Identifies the LDAP X.509 Certificate schema elements
          introduced in this document.

7.2.  Descriptor Registration

  The IANA has updated the LDAP
  Descriptor registry [RFC44520] as indicated below.

     Subject: Request for LDAP Descriptor Registration
     Descriptor (short name): see table
     Object Identifier: see table
     Person & email address to contact for further information:
         Kurt Zeilenga <[email protected]>
     Usage: see table
     Specification: RFC 4523
     Author/Change Controller: IESG

     algorithmIdentifierMatch     M 2.5.13.40
     authorityRevocationList      A 2.5.4.38 *
     cACertificate                A 2.5.4.37 *
     cRLDistributionPoint         O 2.5.6.19 *
     certificateExactMatch        M 2.5.13.34
     certificateListExactMatch    M 2.5.13.38
     certificateListMatch         M 2.5.13.39
     certificateMatch             M 2.5.13.35
     certificatePairExactMatch    M 2.5.13.36
     certificatePairMatch         M 2.5.13.37
     certificateRevocationList    A 2.5.4.39 *
     certificationAuthority       O 2.5.6.16 *
     certificationAuthority-V2    O 2.5.6.16.2 *
     crossCertificatePair         A 2.5.4.40 *



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     deltaCRL                     O 2.5.6.23 *
     deltaRevocationList          A 2.5.4.53 *
     pkiCA                        O 2.5.6.22 *
     pkiUser                      O 2.5.6.21 *
     strongAuthenticationUser     O 2.5.6.15 *
     supportedAlgorithms          A 2.5.4.52 *
     userCertificate              A 2.5.4.36 *
     userSecurityInformation      O 2.5.6.18 *

     * Updates previous registration

8.  Acknowledgements

  This document is based on X.509, a product of the ITU-T.  A number of
  LDAP schema definitions were based on those found in RFCs 2252 and
  2256, both products of the IETF ASID WG.  The ABNF productions in
  Appendix A were provided by Steven Legg.  Additional material was
  borrowed from prior works by David Chadwick and Steven Legg to refine
  the LDAP X.509 schema.

9.  References

9.1.  Normative References

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

  [RFC3641]  Legg, S., "Generic String Encoding Rules (GSER) for ASN.1
             Types", RFC 3641, October 2003.

  [RFC4510]  Zeilenga, K., Ed., "Lightweight Directory Access Protocol
             (LDAP): Technical Specification Road Map", RFC 4510, June
             2006.

  [RFC4512]  Zeilenga, K., "Lightweight Directory Access Protocol
             (LDAP): Directory Information Models", RFC 4512, June
             2006.

  [RFC4522]  Legg, S., "Lightweight Directory Access Protocol (LDAP):
             The Binary Encoding Option", RFC 4522, June 2006.

  [X.509]    International Telecommunication Union - Telecommunication
             Standardization Sector, "The Directory: Authentication
             Framework", X.509(2000).







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RFC 4523                   LDAP X.509 Schema                   June 2006


  [X.521]    International Telecommunication Union - Telecommunication
             Standardization Sector, "The Directory: Selected Object
             Classes", X.521(2000).

  [X.690]    International Telecommunication Union - Telecommunication
             Standardization Sector, "Specification of ASN.1 encoding
             rules: Basic Encoding Rules (BER), Canonical Encoding
             Rules (CER), and Distinguished Encoding Rules (DER)",
             X.690(2002) (also ISO/IEC 8825-1:2002).

9.2.  Informative References

  [RFC1777]  Yeong, W., Howes, T., and S. Kille, "Lightweight Directory
             Access Protocol", RFC 1777, March 1995.

  [RFC2156]  Kille, S., "MIXER (Mime Internet X.400 Enhanced Relay):
             Mapping between X.400 and RFC 822/MIME", RFC 2156, January
             1998.

  [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.

  [RFC3494]  Zeilenga, K., "Lightweight Directory Access Protocol
             version 2 (LDAPv2) to Historic Status", RFC 3494, March
             2003.

  [RFC3642]  Legg, S., "Common Elements of Generic String Encoding
             Rules (GSER) Encodings", RFC 3642, October 2003.

  [RFC4234]  Crocker, D. and P. Overell, "Augmented BNF for Syntax
             Specifications: ABNF", RFC 4234, October 2005.

  [RFC4511]  Sermersheim, J., Ed., "Lightweight Directory Access
             Protocol (LDAP): The Protocol", RFC 4511, June 2006.

  [RFC4513]  Harrison, R. Ed., "Lightweight Directory Access Protocol
             (LDAP): Authentication Methods and Security Mechanisms",
             RFC 4513, June 2006.

  [RFC4520]  Zeilenga, K., "Internet Assigned Numbers Authority (IANA)
             Considerations for the Lightweight Directory Access
             Protocol (LDAP)", BCP 64, RFC 4520, June 2006.







Zeilenga                    Standards Track                    [Page 14]

RFC 4523                   LDAP X.509 Schema                   June 2006


Appendix A.

  This appendix is informative.

  This appendix provides ABNF [RFC4234] grammars for GSER-based
  [RFC3641] LDAP-specific encodings specified in this document.  These
  grammars where produced using, and relying on, Common Elements for
  GSER Encodings [RFC3642].

A.1.  CertificateExactAssertion

  CertificateExactAssertion = "{" sp cea-serialNumber ","
       sp cea-issuer sp "}"

  cea-serialNumber = id-serialNumber msp CertificateSerialNumber
  cea-issuer = id-issuer msp Name

  id-serialNumber =
       %x73.65.72.69.61.6C.4E.75.6D.62.65.72 ; 'serialNumber'
  id-issuer = %x69.73.73.75.65.72 ; 'issuer'

  Name = id-rdnSequence ":" RDNSequence
  id-rdnSequence = %x72.64.6E.53.65.71.75.65.6E.63.65 ; 'rdnSequence'

  CertificateSerialNumber = INTEGER

A.2.  CertificateAssertion

CertificateAssertion = "{" [ sp ca-serialNumber ]
    [ sep sp ca-issuer ]
    [ sep sp ca-subjectKeyIdentifier ]
    [ sep sp ca-authorityKeyIdentifier ]
    [ sep sp ca-certificateValid ]
    [ sep sp ca-privateKeyValid ]
    [ sep sp ca-subjectPublicKeyAlgID ]
    [ sep sp ca-keyUsage ]
    [ sep sp ca-subjectAltName ]
    [ sep sp ca-policy ]
    [ sep sp ca-pathToName ]
    [ sep sp ca-subject ]
    [ sep sp ca-nameConstraints ] sp "}"

ca-serialNumber = id-serialNumber msp CertificateSerialNumber
ca-issuer = id-issuer msp Name
ca-subjectKeyIdentifier = id-subjectKeyIdentifier msp
    SubjectKeyIdentifier
ca-authorityKeyIdentifier = id-authorityKeyIdentifier msp
    AuthorityKeyIdentifier



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RFC 4523                   LDAP X.509 Schema                   June 2006


ca-certificateValid = id-certificateValid msp Time
ca-privateKeyValid = id-privateKeyValid msp GeneralizedTime
ca-subjectPublicKeyAlgID = id-subjectPublicKeyAlgID msp
    OBJECT-IDENTIFIER
ca-keyUsage = id-keyUsage msp KeyUsage
ca-subjectAltName = id-subjectAltName msp AltNameType
ca-policy = id-policy msp CertPolicySet
ca-pathToName = id-pathToName msp Name
ca-subject = id-subject msp Name
ca-nameConstraints = id-nameConstraints msp NameConstraintsSyntax

id-subjectKeyIdentifier =
    %x73.75.62.6A.65.63.74.4B.65.79.49.64.65.6E.74.69.66.69.65.72
    ; 'subjectKeyIdentifier'
id-authorityKeyIdentifier =
    %x61.75.74.68.6F.72.69.74.79.4B.65.79.49.64.65.6E.74.69.66.69.65.72
    ; 'authorityKeyIdentifier'
id-certificateValid = %x63.65.72.74.69.66.69.63.61.74.65.56.61.6C.69.64
    ; 'certificateValid'
id-privateKeyValid = %x70.72.69.76.61.74.65.4B.65.79.56.61.6C.69.64
    ; 'privateKeyValid'
id-subjectPublicKeyAlgID  =
    %x73.75.62.6A.65.63.74.50.75.62.6C.69.63.4B.65.79.41.6C.67.49.44
    ; 'subjectPublicKeyAlgID'
id-keyUsage = %x6B.65.79.55.73.61.67.65 ; 'keyUsage'
id-subjectAltName = %x73.75.62.6A.65.63.74.41.6C.74.4E.61.6D.65
    ; 'subjectAltName'
id-policy = %x70.6F.6C.69.63.79 ; 'policy'
id-pathToName = %x70.61.74.68.54.6F.4E.61.6D.65 ; 'pathToName'
id-subject = %x73.75.62.6A.65.63.74 ; 'subject'
id-nameConstraints = %x6E.61.6D.65.43.6F.6E.73.74.72.61.69.6E.74.73
    ; 'nameConstraints'

SubjectKeyIdentifier = KeyIdentifier

KeyIdentifier = OCTET-STRING

AuthorityKeyIdentifier = "{" [ sp aki-keyIdentifier ]
    [ sep sp aki-authorityCertIssuer ]
    [ sep sp aki-authorityCertSerialNumber ] sp "}"

aki-keyIdentifier = id-keyIdentifier msp KeyIdentifier
aki-authorityCertIssuer = id-authorityCertIssuer msp GeneralNames

GeneralNames = "{" sp GeneralName *( "," sp GeneralName ) sp "}"
GeneralName  = gn-otherName
    / gn-rfc822Name
    / gn-dNSName



Zeilenga                    Standards Track                    [Page 16]

RFC 4523                   LDAP X.509 Schema                   June 2006


    / gn-x400Address
    / gn-directoryName
    / gn-ediPartyName
    / gn-uniformResourceIdentifier
    / gn-iPAddress
    / gn-registeredID

gn-otherName = id-otherName ":" OtherName
gn-rfc822Name = id-rfc822Name ":" IA5String
gn-dNSName = id-dNSName ":" IA5String
gn-x400Address = id-x400Address ":" ORAddress
gn-directoryName = id-directoryName ":" Name
gn-ediPartyName = id-ediPartyName ":" EDIPartyName
gn-iPAddress = id-iPAddress ":" OCTET-STRING
gn-registeredID = gn-id-registeredID ":" OBJECT-IDENTIFIER

gn-uniformResourceIdentifier = id-uniformResourceIdentifier
    ":" IA5String

id-otherName = %x6F.74.68.65.72.4E.61.6D.65 ; 'otherName'
gn-id-registeredID = %x72.65.67.69.73.74.65.72.65.64.49.44
    ; 'registeredID'

OtherName = "{" sp on-type-id "," sp on-value sp "}"
on-type-id = id-type-id msp OBJECT-IDENTIFIER
on-value = id-value msp Value
    ;; <Value> as defined in Section 3 of [RFC3641]

id-type-id = %x74.79.70.65.2D.69.64 ; 'type-id'
id-value = %x76.61.6C.75.65 ; 'value'

ORAddress = dquote *SafeIA5Character dquote
SafeIA5Character = %x01-21 / %x23-7F / ; ASCII minus dquote
    dquote dquote ; escaped double quote
dquote = %x22 ; '"' (double quote)

;; Note: The <ORAddress> rule encodes the x400Address component
;; of a GeneralName as a character string between double quotes.
;; The character string is first derived according to Section 4.1
;; of [RFC2156], and then any embedded double quotes are escaped
;; by being repeated. This resulting string is output between
;; double quotes.

EDIPartyName = "{" [ sp nameAssigner "," ] sp partyName sp "}"
nameAssigner = id-nameAssigner msp DirectoryString
partyName = id-partyName msp DirectoryString
id-nameAssigner = %x6E.61.6D.65.41.73.73.69.67.6E.65.72
    ; 'nameAssigner'



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RFC 4523                   LDAP X.509 Schema                   June 2006


id-partyName    = %x70.61.72.74.79.4E.61.6D.65 ; 'partyName'

aki-authorityCertSerialNumber = id-authorityCertSerialNumber
    msp CertificateSerialNumber

id-keyIdentifier = %x6B.65.79.49.64.65.6E.74.69.66.69.65.72
    ; 'keyIdentifier'
id-authorityCertIssuer =
    %x61.75.74.68.6F.72.69.74.79.43.65.72.74.49.73.73.75.65.72
    ; 'authorityCertIssuer'

id-authorityCertSerialNumber = %x61.75.74.68.6F.72.69.74.79.43
    %x65.72.74.53.65.72.69.61.6C.4E.75.6D.62.65.72
    ; 'authorityCertSerialNumber'

Time = time-utcTime / time-generalizedTime
time-utcTime = id-utcTime ":" UTCTime
time-generalizedTime = id-generalizedTime ":" GeneralizedTime
id-utcTime = %x75.74.63.54.69.6D.65 ; 'utcTime'
id-generalizedTime = %x67.65.6E.65.72.61.6C.69.7A.65.64.54.69.6D.65
    ; 'generalizedTime'

KeyUsage = BIT-STRING / key-usage-bit-list
key-usage-bit-list = "{" [ sp key-usage *( "," sp key-usage ) ] sp "}"

;; Note: The <key-usage-bit-list> rule encodes the one bits in
;; a KeyUsage value as a comma separated list of identifiers.

key-usage = id-digitalSignature
    / id-nonRepudiation
    / id-keyEncipherment
    / id-dataEncipherment
    / id-keyAgreement
    / id-keyCertSign
    / id-cRLSign
    / id-encipherOnly
    / id-decipherOnly

id-digitalSignature = %x64.69.67.69.74.61.6C.53.69.67.6E.61.74
    %x75.72.65 ; 'digitalSignature'
id-nonRepudiation   = %x6E.6F.6E.52.65.70.75.64.69.61.74.69.6F.6E
    ; 'nonRepudiation'
id-keyEncipherment  = %x6B.65.79.45.6E.63.69.70.68.65.72.6D.65.6E.74
    ; 'keyEncipherment'
id-dataEncipherment = %x64.61.74.61.45.6E.63.69.70.68.65.72.6D.65.6E
    %x74 ; "dataEncipherment'
id-keyAgreement     = %x6B.65.79.41.67.72.65.65.6D.65.6E.74
    ; 'keyAgreement'



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RFC 4523                   LDAP X.509 Schema                   June 2006


id-keyCertSign      = %x6B.65.79.43.65.72.74.53.69.67.6E
    ; 'keyCertSign'
id-cRLSign          = %x63.52.4C.53.69.67.6E ; "cRLSign"
id-encipherOnly     = %x65.6E.63.69.70.68.65.72.4F.6E.6C.79
    ; 'encipherOnly'
id-decipherOnly     = %x64.65.63.69.70.68.65.72.4F.6E.6C.79
    ; 'decipherOnly'

AltNameType = ant-builtinNameForm / ant-otherNameForm

ant-builtinNameForm = id-builtinNameForm ":" BuiltinNameForm
ant-otherNameForm = id-otherNameForm ":" OBJECT-IDENTIFIER

id-builtinNameForm = %x62.75.69.6C.74.69.6E.4E.61.6D.65.46.6F.72.6D
    ; 'builtinNameForm'
id-otherNameForm   = %x6F.74.68.65.72.4E.61.6D.65.46.6F.72.6D
    ; 'otherNameForm'

BuiltinNameForm  = id-rfc822Name
    / id-dNSName
    / id-x400Address
    / id-directoryName
    / id-ediPartyName
    / id-uniformResourceIdentifier
    / id-iPAddress
    / id-registeredId

id-rfc822Name = %x72.66.63.38.32.32.4E.61.6D.65 ; 'rfc822Name'
id-dNSName = %x64.4E.53.4E.61.6D.65 ; 'dNSName'
id-x400Address  = %x78.34.30.30.41.64.64.72.65.73.73 ; 'x400Address'
id-directoryName = %x64.69.72.65.63.74.6F.72.79.4E.61.6D.65
    ; 'directoryName'
id-ediPartyName  = %x65.64.69.50.61.72.74.79.4E.61.6D.65
    ; 'ediPartyName'
id-iPAddress = %x69.50.41.64.64.72.65.73.73 ; 'iPAddress'
id-registeredId = %x72.65.67.69.73.74.65.72.65.64.49.64
    ; 'registeredId'

id-uniformResourceIdentifier = %x75.6E.69.66.6F.72.6D.52.65.73.6F.75
    %x72.63.65.49.64.65.6E.74.69.66.69.65.72
    ; 'uniformResourceIdentifier'

CertPolicySet = "{" sp CertPolicyId *( "," sp CertPolicyId ) sp "}"
CertPolicyId = OBJECT-IDENTIFIER

NameConstraintsSyntax = "{" [ sp ncs-permittedSubtrees ]
    [ sep sp ncs-excludedSubtrees ] sp "}"




Zeilenga                    Standards Track                    [Page 19]

RFC 4523                   LDAP X.509 Schema                   June 2006


ncs-permittedSubtrees = id-permittedSubtrees msp GeneralSubtrees
ncs-excludedSubtrees = id-excludedSubtrees  msp GeneralSubtrees

id-permittedSubtrees =
    %x70.65.72.6D.69.74.74.65.64.53.75.62.74.72.65.65.73
    ; 'permittedSubtrees'
id-excludedSubtrees =
    %x65.78.63.6C.75.64.65.64.53.75.62.74.72.65.65.73
    ; 'excludedSubtrees'

GeneralSubtrees = "{" sp GeneralSubtree
    *( "," sp GeneralSubtree ) sp "}"
GeneralSubtree  = "{" sp gs-base
    [ "," sp gs-minimum ]
    [ "," sp gs-maximum ] sp "}"

gs-base = id-base msp GeneralName
gs-minimum = id-minimum msp BaseDistance
gs-maximum = id-maximum msp BaseDistance

id-base = %x62.61.73.65 ; 'base'
id-minimum = %x6D.69.6E.69.6D.75.6D ; 'minimum'
id-maximum = %x6D.61.78.69.6D.75.6D ; 'maximum'

BaseDistance = INTEGER-0-MAX

A.3.  CertificatePairExactAssertion

 CertificatePairExactAssertion = "{" [ sp cpea-issuedTo ]
      [sep sp cpea-issuedBy ] sp "}"
 ;; At least one of <cpea-issuedTo> or <cpea-issuedBy> MUST be present.

 cpea-issuedTo = id-issuedToThisCAAssertion msp
      CertificateExactAssertion
 cpea-issuedBy = id-issuedByThisCAAssertion msp
      CertificateExactAssertion

 id-issuedToThisCAAssertion = %x69.73.73.75.65.64.54.6F.54.68.69.73
      %x43.41.41.73.73.65.72.74.69.6F.6E ; 'issuedToThisCAAssertion'
 id-issuedByThisCAAssertion = %x69.73.73.75.65.64.42.79.54.68.69.73
      %x43.41.41.73.73.65.72.74.69.6F.6E ; 'issuedByThisCAAssertion'










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RFC 4523                   LDAP X.509 Schema                   June 2006


A.4.  CertificatePairAssertion

  CertificatePairAssertion = "{" [ sp cpa-issuedTo ]
       [sep sp cpa-issuedBy ] sp "}"
  ;; At least one of <cpa-issuedTo> and <cpa-issuedBy> MUST be present.

  cpa-issuedTo = id-issuedToThisCAAssertion msp CertificateAssertion
  cpa-issuedBy = id-issuedByThisCAAssertion msp CertificateAssertion

A.5.  CertificateListExactAssertion

  CertificateListExactAssertion = "{" sp clea-issuer ","
       sp clea-thisUpdate
       [ "," sp clea-distributionPoint ] sp "}"

  clea-issuer = id-issuer msp Name
  clea-thisUpdate = id-thisUpdate msp Time
  clea-distributionPoint = id-distributionPoint msp
       DistributionPointName

  id-thisUpdate = %x74.68.69.73.55.70.64.61.74.65 ; 'thisUpdate'
  id-distributionPoint =
       %x64.69.73.74.72.69.62.75.74.69.6F.6E.50.6F.69.6E.74
       ; 'distributionPoint'

  DistributionPointName = dpn-fullName / dpn-nameRelativeToCRLIssuer

  dpn-fullName = id-fullName ":" GeneralNames
  dpn-nameRelativeToCRLIssuer = id-nameRelativeToCRLIssuer ":"
       RelativeDistinguishedName

  id-fullName = %x66.75.6C.6C.4E.61.6D.65 ; 'fullName'
  id-nameRelativeToCRLIssuer = %x6E.61.6D.65.52.65.6C.61.74.69.76.65
       %x54.6F.43.52.4C.49.73.73.75.65.72 ; 'nameRelativeToCRLIssuer'

A.6.  CertificateListAssertion

  CertificateListAssertion = "{" [ sp cla-issuer ]
       [ sep sp cla-minCRLNumber ]
       [ sep sp cla-maxCRLNumber ]
       [ sep sp cla-reasonFlags ]
       [ sep sp cla-dateAndTime ]
       [ sep sp cla-distributionPoint ]
       [ sep sp cla-authorityKeyIdentifier ] sp "}"

  cla-issuer = id-issuer msp Name
  cla-minCRLNumber = id-minCRLNumber msp CRLNumber
  cla-maxCRLNumber = id-maxCRLNumber msp CRLNumber



Zeilenga                    Standards Track                    [Page 21]

RFC 4523                   LDAP X.509 Schema                   June 2006


  cla-reasonFlags = id-reasonFlags msp ReasonFlags
  cla-dateAndTime = id-dateAndTime msp Time

  cla-distributionPoint = id-distributionPoint msp
       DistributionPointName

  cla-authorityKeyIdentifier = id-authorityKeyIdentifier msp
       AuthorityKeyIdentifier

  id-minCRLNumber = %x6D.69.6E.43.52.4C.4E.75.6D.62.65.72
       ; 'minCRLNumber'
  id-maxCRLNumber = %x6D.61.78.43.52.4C.4E.75.6D.62.65.72
       ; 'maxCRLNumber'
  id-reasonFlags = %x72.65.61.73.6F.6E.46.6C.61.67.73 ; 'reasonFlags'
  id-dateAndTime = %x64.61.74.65.41.6E.64.54.69.6D.65 ; 'dateAndTime'

  CRLNumber = INTEGER-0-MAX

  ReasonFlags = BIT-STRING
       / "{" [ sp reason-flag *( "," sp reason-flag ) ] sp "}"

  reason-flag = id-unused
       / id-keyCompromise
       / id-cACompromise
       / id-affiliationChanged
       / id-superseded
       / id-cessationOfOperation
       / id-certificateHold
       / id-privilegeWithdrawn
       / id-aACompromise

  id-unused = %x75.6E.75.73.65.64 ; 'unused'
  id-keyCompromise = %x6B.65.79.43.6F.6D.70.72.6F.6D.69.73.65
       ; 'keyCompromise'
  id-cACompromise = %x63.41.43.6F.6D.70.72.6F.6D.69.73.65
       ; 'cACompromise'
  id-affiliationChanged =
       %x61.66.66.69.6C.69.61.74.69.6F.6E.43.68.61.6E.67.65.64
       ; 'affiliationChanged'
  id-superseded = %x73.75.70.65.72.73.65.64.65.64 ; 'superseded'
  id-cessationOfOperation =
       %x63.65.73.73.61.74.69.6F.6E.4F.66.4F.70.65.72.61.74.69.6F.6E
       ; 'cessationOfOperation'
  id-certificateHold = %x63.65.72.74.69.66.69.63.61.74.65.48.6F.6C.64
       ; 'certificateHold'
  id-privilegeWithdrawn =
       %x70.72.69.76.69.6C.65.67.65.57.69.74.68.64.72.61.77.6E
       ; 'privilegeWithdrawn'



Zeilenga                    Standards Track                    [Page 22]

RFC 4523                   LDAP X.509 Schema                   June 2006


  id-aACompromise = %x61.41.43.6F.6D.70.72.6F.6D.69.73.65
       ; 'aACompromise'

A.7.  AlgorithmIdentifier

  AlgorithmIdentifier = "{" sp ai-algorithm
       [ "," sp ai-parameters ] sp "}"

  ai-algorithm = id-algorithm msp OBJECT-IDENTIFIER
  ai-parameters = id-parameters msp Value
  id-algorithm = %x61.6C.67.6F.72.69.74.68.6D ; 'algorithm'
  id-parameters = %x70.61.72.61.6D.65.74.65.72.73 ; 'parameters'

Author's Address

  Kurt D. Zeilenga
  OpenLDAP Foundation

  EMail: [email protected]
































Zeilenga                    Standards Track                    [Page 23]

RFC 4523                   LDAP X.509 Schema                   June 2006


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.

Intellectual Property

  The IETF takes no position regarding the validity or scope of any
  Intellectual Property Rights or other rights that might be claimed to
  pertain to the implementation or use of the technology described in
  this document or the extent to which any license under such rights
  might or might not be available; nor does it represent that it has
  made any independent effort to identify any such rights.  Information
  on the procedures with respect to rights in RFC documents can be
  found in BCP 78 and BCP 79.

  Copies of IPR disclosures made to the IETF Secretariat and any
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Acknowledgement

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







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