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PKIX Working Group                                   R. Housley (SPYRUS)
Internet Draft                                        W. Ford (Verisign) (VeriSign)
                                                          W. Polk (NIST)
                                                      D. Solo (Citicorp)
expires in six months                                     March 25,                                      June 16, 1998


                Internet X.509 Public Key Infrastructure

                   X.509

                      Certificate and CRL Profile

                  <draft-ietf-pkix-ipki-part1-07.txt>

                  <draft-ietf-pkix-ipki-part1-08.txt>


Status of this Memo

   This document is an Internet-Draft.  Internet-Drafts are working
   documents of the Internet Engineering Task Force (IETF), its areas,
   and its working groups.  Note that other groups may also distribute
   working documents as Internet-Drafts.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet- Drafts as reference
   material or to cite them other than as "work in progress."

   To view learn the entire list of current Internet-Drafts, status of any Internet-Draft, please check the
   "1id-abstracts.txt" listing contained in the Internet-Drafts Internet- Drafts Shadow
   Directories on ftp.is.co.za (Africa), ftp.nordu.net
   (Northern Europe), ftp.nis.garr.it (Southern Europe), nic.nordu.net (Europe),
   munnari.oz.au
   (Pacific Pacific Rim), ftp.ietf.org ds.internic.net (US East Coast), or
   ftp.isi.edu (US West Coast).

   Copyright (C) The Internet Society (date). All Rights Reserved.


Abstract

   This is the seventh eighth draft of the Internet Public Key Infrastructure
   X.509 Certificate and CRL Profile.  This draft is a complete
   specification.  This text includes minor modifications over the
   previous draft. This draft introduces UTF8 support, clarifies name encoding and comparison
   issues, updates the path validation process to conform with the
   current X.509 specification,
   forbids wildcarding in subject alternative names, specifies performance enhancements for
   path building, and clarifies conformance requirements.

   The Entrust patent statement in section 9.5 is a placeholder. Recent
   negotiations have produced new licensing terms; a new statement
   aligned with those terms will be inserted when available.



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   The key words "MUST", "REQUIRED", "SHOULD", "RECOMMENDED", and "MAY"
   in this document are to be interpreted as described in RFC 2119.

   Please send comments on this document to the ietf-pkix@tandem.com
   mail list.














































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                           Table of Contents



   1  Executive Summary ...........................................    5  Introduction ................................................    6
   2  Requirements and Assumptions ................................    6    7
   2.1  Communication and Topology ................................    6    7
   2.2  Acceptability Criteria ....................................    7    8
   2.3  User Expectations .........................................    7    8
   2.4  Administrator Expectations ................................    7    8
   3  Overview of Approach ........................................    7    8
   3.1  X.509 Version 3 Certificate ...............................    9   10
   3.2  Certification Paths and Trust .............................   10   11
   3.3  Revocation ................................................   12   13
   3.4  Operational Protocols .....................................   13   14
   3.5  Management Protocols ......................................   14
   4  Certificate and Certificate Extensions Profile ..............   15
   4.1  Basic Certificate Fields ..................................   15   16
   4.1.1  Certificate Fields ......................................   16   17
   4.1.1.1  tbsCertificate ........................................   16   17
   4.1.1.2  signatureAlgorithm ....................................   17
   4.1.1.3  signature .............................................   17  signatureValue ........................................   18
   4.1.2  TBSCertificate ..........................................   17   18
   4.1.2.1  Version ...............................................   18
   4.1.2.2  Serial number .........................................   18
   4.1.2.3  Signature .............................................   18   19
   4.1.2.4  Issuer Name ...........................................   18 ................................................   19
   4.1.2.5  Validity ..............................................   20   21
   4.1.2.5.1  UTCTime .............................................   20   21
   4.1.2.5.2  GeneralizedTime .....................................   20   21
   4.1.2.6  Subject Name ..........................................   21 ...............................................   22
   4.1.2.7  Subject Public Key Info ...............................   21   23
   4.1.2.8  Unique Identifiers ....................................   21   23
   4.1.2.9 Extensions .............................................   22   23
   4.2  Certificate Extensions ....................................   22   23
   4.2.1  Standard Extensions .....................................   23   24
   4.2.1.1  Authority Key Identifier ..............................   23   25
   4.2.1.2  Subject Key Identifier ................................   24   25
   4.2.1.3  Key Usage .............................................   24   26
   4.2.1.4  Private Key Usage Period ..............................   26   27
   4.2.1.5  Certificate Policies ..................................   26   28
   4.2.1.6  Policy Mappings .......................................   28   30
   4.2.1.7  Subject Alternative Name ..............................   29   30
   4.2.1.8  Issuer Alternative Name ...............................   31   32
   4.2.1.9  Subject Directory Attributes ..........................   31   33



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   4.2.1.10  Basic Constraints ....................................   31   33
   4.2.1.11  Name Constraints .....................................   32   33
   4.2.1.12  Policy Constraints ...................................   33   35
   4.2.1.13  CRL Distribution Points ..............................   34
   4.2.1.14  Extended key usage field .............................   35   36
   4.2.1.14  CRL Distribution Points ..............................   38
   4.2.2  Private  Internet Certificate Extensions .............................   36 .........................   38
   4.2.2.1  Authority Information Access ..........................   37   39
   5  CRL and CRL Extensions Profile ..............................   39   40
   5.1  CRL Fields ................................................   39   41
   5.1.1  CertificateList Fields ..................................   40   41
   5.1.1.1  tbsCertList ...........................................   40   42
   5.1.1.2  signatureAlgorithm ....................................   41   42
   5.1.1.3  signature .............................................   41  signatureValue ........................................   42
   5.1.2  Certificate List "To Be Signed" .........................   41   42
   5.1.2.1  Version ...............................................   41   42
   5.1.2.2  Signature .............................................   42   43
   5.1.2.3  Issuer Name ...........................................   42   43
   5.1.2.4  This Update ...........................................   42   43
   5.1.2.5  Next Update ...........................................   42   43
   5.1.2.6  Revoked Certificates ..................................   43   44
   5.1.2.7  Extensions ............................................   43   44
   5.2  CRL Extensions ............................................   43   44
   5.2.1  Authority Key Identifier ................................   44   45
   5.2.2  Issuer Alternative Name .................................   44   45
   5.2.3  CRL Number ..............................................   44
   5.2.4  Issuing Distribution Point ..............................   45
   5.2.5
   5.2.4  Delta CRL Indicator .....................................   45
   5.2.6 Certificate Issuer .......................................
   5.2.5  Issuing Distribution Point ..............................   46
   5.3  CRL Entry Extensions ......................................   46   47
   5.3.1  Reason Code .............................................   47
   5.3.2  Hold Instruction Code ...................................   47   48
   5.3.3  Invalidity Date .........................................   48
   5.3.4  Certificate Issuer ......................................   49
   6  Certificate Path Validation .................................   48   49
   6.1  Basic Path Validation .....................................   50
   6.2  Extending Path Validation .................................   54
   7  Algorithm Support ...........................................   53   54
   7.1  One-way Hash Functions ....................................   53   55
   7.1.1  MD2 One-way Hash Function ...............................   53   55
   7.1.2  MD5 One-way Hash Function ...............................   54   55
   7.1.3  SHA-1 One-way Hash Function .............................   54   55
   7.2  Signature Algorithms ......................................   54   56
   7.2.1  RSA Signature Algorithm .................................   55   56
   7.2.2  DSA Signature Algorithm .................................   56   57
   7.3  Subject Public Key Algorithms .............................   57   58
   7.3.1  RSA Keys ................................................   57   58
   7.3.2  Diffie-Hellman Key Exchange Key ..........................   58 .........................   59
   7.3.3  DSA Signature Keys .......................................   59
   References ..................................................... ......................................   60
   Patent Statements ..............................................   62
   Appendix A. ASN.1 Structures and OIDs ..........................   66
   8  References ..................................................   61



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   9  Patent Statements ...........................................   63
   9.1  Digital Signature Algorithm (DSA) .........................   64
   9.2  RSA Signature and Encryption ..............................   64
   9.3  Diffie-Hellman Key Agreement ..............................   65
   9.4  Hellman-Merkle Public Key Cryptography ....................   65
   9.5  CRL Distribution Points and Related Mechanisms ............   65
   10  Security Considerations ....................................   66
   Appendix A.  ASN.1 Structures and OIDs .........................   69
   A.1 Explicitly Tagged Module, 1988 Syntax ......................   69
   A.1 Implicitly Tagged Module, 1988 Syntax ......................   83
   Appendix B.  1993 ASN.1 Structures and OIDs .....................   83 ....................   90
   B.1 Explicitly Tagged Module, 1993 Syntax ......................   90
   B.2 Implicitly Tagged Module, 1993 Syntax ......................  107
   Appendix C.  ASN.1 Notes ........................................  100 .......................................  114
   Appendix D.  Examples ...........................................  101 ..........................................  115
   D.1  Certificate ................................................  102 ...............................................  115
   D.1.1  ASN.1 Dump of "Self-Signed" Certificate ..................  102 .................  116
   D.1.2  Pretty Print of "Self-Signed" Certificate ................  104 ...............  118
   D.2  Certificate ................................................  106 ...............................................  119
   D.2.1  Basic ASN.1 Dump of "End Entity" Certificate .............  106 ............  119
   D.2.2  Pretty Print of "End Entity" Certificate .................  108 ................  121
   D.3  End-Entity Certificate Using RSA ...........................  110 ..........................  122
   D.4  Certificate Revocation List ................................  114
   Security Considerations ........................................  111 ...............................  127
   Appendix E.  Author Addresses ...............................................  116 ..................................  128
   Appendix F.  Full Copyright Statement ..........................  128


























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1  Executive Summary  Introduction

   This specification is one part of a multipart standard family of standards for the X.509
   Public Key Infrastructure (PKI) for the Internet.  This specification
   is a standalone document; implementations of this standard may
   proceed independent from the other parts.

   This specification profiles the format and semantics of certificates
   and certificate revocation lists for the Internet PKI.  Procedures
   are described for processing of certification paths in the Internet
   environment.  Encoding rules are provided for popular cryptographic
   algorithms.  Finally, ASN.1 modules are provided in the appendices
   for all data structure structures defined or referenced.

   The specification describes the requirements which inspire the crea-
   tion of this document and the assumptions which affect its scope in
   Section 2.  Section 3 presents an architectural model and describes
   its relationship to previous IETF and ISO ISO/IEC/ITU standards.  In particular, par-
   ticular, this document's relationship with the IETF PEM specifications specifica-
   tions and the
   ISO ISO/IEC/ITU X.509 documents are described.

   The specification profiles the X.509 version 3 certificate in Section
   4, and the X.509 version 2 certificate revocation list (CRL) in Sec-
   tion 5. The profiles include the identification of ISO ISO/IEC/ITU and
   ANSI extensions which may be useful in the Internet PKI and definition of
   new extensions to meet the Internet's requirements. PKI. The profiles
   are presented in the 1988 Abstract Syntax Notation One (ASN.1) rather
   than the 1993 1994 syntax used in the ISO ISO/IEC/ITU standards.  The ASN.1 notation
   assumes implict tagging throughout.

   This specification also includes path validation procedures in Sec-
   tion 6.  These procedures are based upon the ISO ISO/IEC/ITU definition,
   but the presentation assumes a self-signed root trusted CA certificate.
   Implementations are required to derive the same results but are not
   required to use the specified procedures.

   Finally,

   Section 7 of the specification describes procedures for
   identification identifica-
   tion and encoding of public key materials and digital sig-
   natures. signatures.
   Implementations are not required to use any particular cryptographic
   algorithms.  However, conforming implementations which use the identified iden-
   tified algorithms are required to identify and encode the public key
   materials and digital signatures as described.

   Finally, four appendices are provided to aid implementers.  Appendix
   A contains all ASN.1 structures defined or referenced within this
   specification.  As above, the material is presented in the 1988
   Abstract Syntax Notation One (ASN.1) rather than the 1993 1994 syntax.
   Appendix B contains the same information in the 1993 1994 ASN.1 notation. notation
   as a service to implementers using updated toolsets.  However, Appen-
   dix A takes precedence in case of conflict.  Appendix C contains notes on less familiar features of the ASN.1



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   notes on less familiar features of the ASN.1 notation used within
   this specification.  Appendix D contains exam-
   ples examples of a conforming
   certificate and a conforming CRL.

2  Requirements and Assumptions

   Goal

   The goal of this specification is to develop a profile and associated management structure to facilitate
   the adoption/use use of X.509 certificates within Internet applications for those
   communities wishing to make use of X.509 tech-
   nology. technology. Such applications applica-
   tions may include WWW, electronic mail, user authentication, and IPSEC, as well as others.
   IPsec.  In order to relieve some of the obstacles to using X.509 certificates, cer-
   tificates, this document defines a profile to promote the development
   of certificate manage-
   ment management systems; development of application tools;
   and interoperability determined by policy, as opposed to syntax. policy.

   Some communities will need to supplement, or possibly replace, this
   profile in order to meet the requirements of specialized application
   domains or environments with additional authorization, assurance, or
   operational requirements.  However, for basic applications, common
   representations of frequently used attributes are defined so that
   application developers can obtain necessary information without
   regard to the issuer of a particular certificate or certificate revo-
   cation list (CRL).

   A certificate user should review the certification practice Statement
   (CPS) certificate policy generated by
   the CA certification authority (CA) before relying on the authentication
   or non-repudiation services associated with the public key in a particu-
   lar par-
   ticular certificate.  To this end, this standard does not prescribe
   legally binding rules or duties.

   As supplemental authorization and attribute management tools emerge,
   such as attribute certificates, it may be appropriate to limit the
   authenticated attributes that are included in a certificate.  These
   other management tools may be provide more appropriate method methods of conveying con-
   veying many authenticated attributes.

2.1  Communication and Topology

   The users of certificates will operate in a wide range of environ-
   ments with respect to their communication topology, especially users
   of secure electronic mail.  This profile supports users without high
   bandwidth, real-time IP connectivity, or high connection availablity. availabil-
   ity.  In addition, the profile allows for the presence of firewall or
   other filtered communication.

   This profile does not assume the deployment of an X.500 Directory
   system.  The profile does not prohibit the use of an X.500 Directory,
   but other means of distributing certificates and certificate



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   revocation lists (CRLs) are supported. may be used.

2.2  Acceptability Criteria

   The goal of the Internet Public Key Infrastructure (PKI) is to meet
   the needs of deterministic, automated identification, authentication,
   access control, and authorization functions. Support for these ser-
   vices determines the attributes contained in the certificate as well
   as the ancillary control information in the certificate such as pol-
   icy data and certification path constraints.

2.3  User Expectations

   Users of the Internet PKI are people and processes who use client
   software and are the subjects named in certificates.  These uses
   include readers and writers of electronic mail, the clients for WWW
   browsers, WWW servers, and the key manager for IPSEC IPsec within a router.
   This profile recognizes the limitations of the platforms these users
   employ and the sophistication/attentiveness limitations in sophistication and attentiveness of the
   users themselves.  This manifests itself in minimal user configuration configura-
   tion responsibility (e.g., root trusted CA keys, rules), explicit platform
   usage constraints within the certificate, certification path constraints con-
   straints which shield the user from many malicious actions, and
   applications which sensibly automate validation functions.

2.4  Administrator Expectations

   As with users, user expectations, the Internet PKI profile is structured to
   support the individuals who generally operate Certification Authorities (CAs). CAs.  Providing
   administrators with unbounded choices increases the chances that a
   subtle CA administrator mistake will result in broad comprom-
   ise. compromise.
   Also, unbounded choices greatly complicates complicate the software that must
   process and validate the certificates created by the CA.

3  Overview of Approach

   Following is a simplified view of the architectural model assumed by
   the PKIX specifications.













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       +---+
       | C |                       +------------+
       | e | <-------------------->| End entity |
       | r |       Operational     +------------+
       | t |       transactions          ^
       |   |      and management         |  Management
       | / |       transactions          |  transactions
       |   |                             |                PKI users
       | C |    PKI users                             v
       | R |             -------+-------+--------+------       -------------------+--+-----------+----------------
       | L |   PKI management                          ^              ^
       |   |      entities                          |              |  PKI management
       |   |                          v              |      entities
       | R |                       +------+          |
       | e | <-------------- | <---------------------| RA   | <-----+ <---+    |
       | p |  Publish certificate   |      |  +------+     |    |
       | o |       publish   +------+                                    |    |
       | s |                                    |    |
       | I |                                    v    v
       | t |                                +------------+
       | o | <--------------------------| <------------------------------|     CA     |
       | r |   Publish certificate publish          +------------+
       | y |   Publish CRL publish                         ^
       |   |                                       |
       +---+                                   |                        Management     |
                                    transactions   |
                                                   v
                                               +------+
                                               |  CA  |
                                               +------+

                          Figure 1 - PKI Entities

   The components in this model are:

   end entity:  user of PKI certificates and/or end user system that
                is the subject of a certificate;
   CA:          certification authority;
   RA:          registration authority, i.e., an optional system to
                which a CA delegates certain management functions;
   repository:  a system or collection of distributed systems that
                store certificates and CRLs and serves as a means of
                distributing these certificates and CRLs to end
                entities.







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3.1  X.509 Version 3 Certificate

   Application of public key technology requires the user

   Users of a public key to must be confident that the public associated private
   key belongs to is owned by the correct remote subject (person or system) with
   which an encryption or digital signa-
   ture signature mechanism will be used.
   This confidence is obtained through the use of public key certificates, certifi-
   cates, which are data structures that bind public key values to subjects. sub-
   jects.  The binding is achieved by having a trusted certification authority (CA) CA digitally sign
   each certificate.  A certificate has a limited valid lifetime which
   is indicated in its signed contents.  Because a certificate's signature signa-
   ture and timeliness can be independently checked by a certificate-using certificate-
   using client, certifi-
   cates certificates can be distributed via untrusted communications communi-
   cations and server sys-
   tems, systems, and can be cached in unsecured storage in
   certificate-using systems.

   The standard known as

   ITU-T X.509 (formerly CCITT X.509) or ISO/IEC ISO/IEC/ITU 9594-8, which was
   first published in 1988 as part of the X.500 Direc-
   tory recommendations, Directory recommenda-
   tions, defines a standard certificate format. format [X.509]. The cer-
   tificate certificate
   format in the 1988 standard is called the version 1 (v1) format.
   When X.500 was revised in 1993, two more fields were added, resulting
   in the version 2 (v2) format. These two fields are may be used to support
   directory access control.

   The Internet Privacy Enhanced Mail (PEM) proposals, RFCs, published in 1993,
   include specifications for a public key infrastructure based on X.509
   v1 certificates [RFC 1422].  The experience gained in attempts to
   deploy RFC 1422 made it clear that the v1 and v2 certificate for-
   mats formats
   are deficient in several respects.  Most importantly, more fields
   were needed to carry information which PEM design and imple-
   mentation implementation
   experience has proven necessary.  In response to these new
   requirements, ISO/IEC require-
   ments, ISO/IEC/ITU and ANSI X9 developed the X.509 version 3 (v3)
   certificate format.  The v3 format extends the v2 format by adding
   provision for additional extension fields.  Particular extension
   field types may be specified in standards or may be defined and
   registered by any organization or community. In June 1996, standardi-
   zation of the basic v3 format was completed [X.509].

   ISO/IEC

   ISO/IEC/ITU and ANSI X9 have also developed standard extensions for
   use in the v3 extensions field [X.509][X9.55].  These extensions can con-
   vey
   convey such data as additional subject identification information,
   key attribute information, policy information, and certification path
   constraints.

   However, the ISO/IEC ISO/IEC/ITU and ANSI X9 standard extensions are very
   broad in their applicability.  In order to develop interoperable implementa-
   tions
   implementations of X.509 v3 systems for Internet use, it is necessary
   to specify a profile for use of the X.509 v3 extensions tailored for
   the



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   for Internet WWW, electronic mail, and IPSEC IPsec applications. Environments Environ-
   ments with additional requirements may build on this profile or may
   replace it.

3.2  Certification Paths and Trust

   A user of a security service requiring knowledge of a public key gen-
   erally needs to obtain and validate a certificate containing the
   required public key.  If the public-key user does not already hold an
   assured copy of the public key of the CA that signed the certificate,
   then it might need an additional certificate to obtain that public
   key.  In general, a chain of multiple certificates may be needed,
   comprising a certificate of the public key owner (the end entity)
   signed by one CA, and zero or more additional certificates of CAs
   signed by other CAs.  Such chains, called certification paths, are
   required because a public key user is only initialized with a limited
   number of assured CA public keys.

   There are different ways in which CAs might be configured in order
   for public key users to be able to find certification paths.  For
   PEM, RFC 1422 defined a rigid hierarchical structure of CAs.  There
   are three types of PEM certification authority:

      (a)  Internet Policy Registration Authority (IPRA):  This author-
      ity, operated under the auspices of the Internet Society, acts as
      the root of the PEM certification hierarchy at level 1.  It issues
      certificates only for the next level of authorities, PCAs.  All
      certification paths start with the IPRA.

      (b)  Policy Certification Authorities (PCAs):  PCAs are at level 2
      of the hierarchy, each PCA being certified by the IPRA.  A PCA
      must establish and publish a statement of its policy with respect
      to certifying users or subordinate certification authorities.
      Distinct PCAs aim to satisfy different user needs. For example,
      one PCA (an organizational PCA) might support the general elec-
      tronic mail needs of commercial organizations, and another PCA (a
      high-assurance PCA) might have a more stringent policy designed
      for satisfying legally binding digital signature requirements.

      (c)  Certification Authorities (CAs):  CAs are at level 3 of the
      hierarchy and can also be at lower levels. Those at level 3 are
      certified by PCAs.  CAs represent, for example, particular organi-
      zations, particular organizational units (e.g., departments,
      groups, sections), or particular geographical areas.

   RFC 1422 furthermore has a name subordination rule which requires
   that a CA can only issue certificates for entities whose names are



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   subordinate (in the X.500 naming tree) to the name of the CA itself.



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   The trust associated with a PEM certification path is implied by the
   PCA name. The name subordination rule ensures that CAs below the PCA
   are sensibly constrained as to the set of subordinate entities they
   can certify (e.g., a CA for an organization can only certify entities
   in that organization's name tree). Certificate user systems are able
   to mechanically check that the name subordination rule has been fol-
   lowed.

   The RFC 1422 was based upon uses the X.509 v1 certificate formats. The limitations
   of X.509 v1 required imposition of several structural restrictions to
   clearly associate policy information or restrict the utility of certificates. cer-
   tificates.  These restrictions included:

      (a) a pure top-down hierarchy, with all certification paths start-
      ing from the root; IPRA;

      (b) a naming subordination rule restricting the names of a CA's
      subjects; and

      (c) use of the PCA concept, which requires knowledge of individual
      PCAs to be built into certificate chain verification logic.
      Knowledge of individual PCAs was required to determine if a chain
      could be accepted.

   With X.509 v3, most of the requirements addressed by RFC 1422 can be
   addressed using certificate extensions, without a need to restrict
   the CA structures used.  In particular, the certificate extensions
   relating to certificate policies obviate the need for PCAs and the
   constraint extensions obviate the need for the name subordination
   rule.  As a result, this document supports a more flexible architec-
   ture, including:

      (a) Certification paths may start with a public key of a CA in a
      user's own domain, or with the public key of the top of a hierar-
      chy.  Starting with the public key of a CA in a user's own domain
      has certain advantages.  In many some environments, the local domain is
      often
      the most trusted.  Initialization and key-pair-update opera-
      tions can often be more effectively conducted between an end
      entity and a local management system.

      (b)  Name constraints may be imposed through explicit inclusion of
      a name constraints extension in a certificate, but are not
      required.

      (c)  Policy extensions and policy mappings replace the PCA con-
      cept, which permits a greater degree of automation.  The applica-
      tion can determine if the certification path is acceptable based



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      on the contents of the certificates instead of a priori knowledge
      of PCAs. This permits the full process automation of certificate chain pro-
      cessing to be implemented in software. processing.




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3.3  Revocation

   When a certificate is issued, it is expected to be in use for its
   entire validity period.  However, various circumstances may cause a
   certificate to become invalid prior to the expiration of the validity
   period. Such circumstances might include change of name, change of
   association associa-
   tion between subject and CA (e.g., an employee terminates employment
   with an organization), and compromise or suspected compromise of the
   corresponding private key.  Under such cir-
   cumstances, circumstances, the CA needs to
   revoke the certificate.

   X.509 defines one method of certificate revocation.  This method
   involves each CA periodically issuing a signed data structure called
   a certificate revocation list (CRL).  A CRL is a time stamped list
   identifying revoked certificates which is signed by a CA and made
   freely available in a public repository.  Each revoked certificate is
   identified in a CRL by its certificate serial number. When a
   certificate-using system uses a certificate (e.g., for verifying a
   remote user's digital signature), that system not only checks the
   certificate signature and validity but also acquires a suitably-
   recent CRL and checks that the certificate serial number is not on
   that CRL.  The meaning of "suitably-recent" may vary with local pol-
   icy, but it usually means the most recently-issued CRL.  A CA issues
   a new CRL on a regular periodic basis (e.g., hourly, daily, or
   weekly).  Entries are  An entry is added to CRLs as revocations occur, and an
   entry may be removed when the certificate expiration date is reached. CRL as part of the next update
   following notification of revocation. An entry may be removed from
   the CRL after appearing on one regularly scheduled CRL issued beyond
   the revoked certificate's validity period.

   An advantage of this revocation method is that CRLs may be distri-
   buted by exactly the same means as certificates themselves, namely,
   via untrusted communications and server systems.

   One limitation of the CRL revocation method, using untrusted communi-
   cations and servers, is that the time granularity of revocation is
   limited to the CRL issue period.  For example, if a revocation is
   reported now, that revocation will not be reliably notified to
   certificate-using systems until the next periodic CRL is issued --
   this may be up to one hour, one day, or one week depending on the
   frequency that the CA issues CRLs.

   Another potential problem with CRLs is the risk of a CRL growing to
   an entirely unacceptable size.  In the 1988 and 1993 versions of
   X.509, the CRL for the end-user certificates needed to cover the
   entire population of end-users for one CA.  It is desirable to allow
   such populations to be in the range of thousands, tens of thousands,



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   or possibly even hundreds of thousands of users. The end-user CRL is
   therefore at risk of growing to such sizes, which present major com-
   munication and storage overhead problems.  With the version 2 CRL
   format, introduced along with the v3 certificate format, it becomes
   possible to arbitrarily divide the population of certificates for one
   CA into a number of partitions, each partition being associated with
   one CRL distribution point (e.g., directory entry or URL) from which
   CRLs are distributed.  Therefore, the maximum CRL size can be con-
   trolled by a CA.  Separate CRL distribution points can also exist for
   different revocation reasons.  For example, routine revocations
   (e.g., name change) may be placed on a different CRL to revocations
   resulting from suspected key compromises, and policy may specify that
   the latter CRL be updated and issued more frequently than the former.

   As with the X.509 v3 certificate format, in order to facilitate
   interoperable implementations from multiple vendors, the X.509 v2 CRL
   format needs to be profiled for Internet use.  It is one goal of this
   document to specify that profile.

   Furthermore, it is recognized that  However, this profile does not
   require CAs to issue CRLs. Message formats and protocols supporting
   on-line revocation notification may be defined in other PKIX specifi-
   cations.  On-line methods of revocation notification may be



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   applicable in some environments as an alternative to the X.509 CRL.
   On-line revocation checking may significantly reduces reduce the latency
   between a revocation report and the next issue distribution of a CRL. the information
   to relying parties.  Once the CA accepts the report as authentic and
   valid, any query to the on-line service will correctly reflect the
   certificate validation impacts of the revocation.  However, these
   methods impose new secu-
   rity security requirements; the certificate validator
   must trust the on-line validation service while the repository did does
   not need to be trusted.

   Therefore, this profile also considers standard approaches to on-line
   revocation notification.  The PKIX series of specifications defines a
   set of standard message formats supporting these functions in [PKIX-
   OCSP].  The protocols for conveying these messages in different
   environments are also specified.

3.4  Operational Protocols

   Operational protocols are required to deliver certificates and CRLs
   (or status information) to certificate using client systems. Provi-
   sion is needed for a variety of different means of certificate and
   CRL delivery, including request/delivery distribution procedures based on E-mail,
   http, X.500, LDAP, HTTP,
   FTP, and WHOIS++. X.500.  Operational protocols supporting these functions are
   defined in other PKIX specifications.  These specifications may
   include definitions
   of, and/or references to, of message formats and procedures for support-
   ing supporting
   all of the above operational environments, including definitions of
   or references to appropriate MIME content types.

   Operational protocols supporting these functions are defined in the
   PKIX specifications [PKIXLDAP], [PKIXFTP] and [PKIXOCSP].



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3.5  Management Protocols

   Management protocols are required to support on-line interactions
   between Public Key Infrastructure (PKI) components. PKI user and management entities.  For example, a management
   protocol might be used between a CA and a client system with which a
   key pair is associated, or between two CAs which cross-
   certify cross-certify each
   other.  The set of functions which potentially need to be supported
   by management protocols include:

      (a)  registration:  This is the process whereby a user first makes
      itself known to a CA (directly, or through an RA), prior to that
      CA issuing  a certificate or certificates for that user.

      (b)  initialization:  Before a client system can operate securely
      it is necessary to install in it necessary key materials which have the
   appropriate appropri-
      ate relationship with keys stored elsewhere in the infras-
   tructure. infrastructure.
      For example, the client needs to be securely initialized with the
      public key of a trusted CA, to be used in validating certificate
      paths.  Furthermore, a client typically needs to be initialized
      with its own key pair(s).

      (c)  certification:  This  is the process in which a CA issues a cer-
   tificate
      certificate for a user's public key, and returns that certificate
      to the user's client system and/or posts that certificate in a
      repository.




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      (d)  key pair recovery:  As an option, user client key materials
      (e.g., a user's private key used for encryption purposes) may be
      backed up by a CA or a key backup system.  If a user needs to
      recover these backed up key materials (e.g., as a result of a forgotten pass-
   word for-
      gotten password or a lost key chain file), an on-line protocol
      exchange may be needed to support such recovery.

      (e)  key pair update:  All key pairs need to be updated regularly,
      i.e., replaced with a new key pair, and new certificates issued.

      (f)  revocation request:  An authorized person advises a CA of an
      abnormal situation requiring certificate revocation.

      (g)  cross-certification:  Two CAs exchange the information necessary used in
      establishing a cross-certificate. A cross-certificate is a certi-
      ficate issued by one CA to establish cross-certificates between those CAs. another CA which contains a CA signa-
      ture key used for issuing certificates.

   Note that on-line protocols are not the only way of implementing the
   above functions.  For all functions there are off-line methods of
   achieving the same result, and this specification does not mandate
   use of on-line protocols.  For example, when hardware tokens are
   used, many of the functions may be achieved as part of the physical
   token delivery.  Furthermore, some of the above functions may be com-
   bined into one protocol exchange.  In particular, two or more of the



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   registration, initialization, and certification functions can be com-
   bined into one protocol exchange.

   The PKIX series of specifications defines may define a set of standard message mes-
   sage formats supporting the above functions in [PKIXMGMT].  The future specifications.
   In that case, the protocols for conveying these messages in different
   environments (on-line, e-
   mail, (e.g., on-line, file transfer, e-mail, and WWW) are will
   also specified be described in [PKIXMGMT]. those specifications.

4  Certificate and Certificate Extensions Profile

   This section presents a profile for public key certificates that will
   foster interoperability and a reusable public key infrastructure. PKI.  This section is based
   upon the X.509 V3 v3 certificate format and the standard certificate
   extensions defined in [X.509].  The ISO docu-
   ments ISO/IEC/ITU documents use the
   1993 version of ASN.1; while this document uses the 1988 ASN.1 syntax, syn-
   tax, the encoded certificate and standard extensions are equivalent.
   This section also defines private extensions required to support a public key infrastructure
   PKI for the Internet com-
   munity. community.

   Certificates may be used in a wide range of applications and environ-
   ments covering a broad spectrum of interoperability goals and a
   broader spectrum of operational and assurance requirements.  The goal



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   of this document is to establish a common baseline for generic appli-
   cations requiring broad interoperability and limited special purpose
   requirements.  In particular, the emphasis will be on supporting the
   use of X.509 v3 certificates for informal internet Internet electronic mail,
   IPSEC,
   IPsec, and WWW applications.  Other efforts are looking at certifi-
   cate profiles for payment systems.

4.1  Basic Certificate Fields

   The X.509 v3 certificate basic syntax is as follows.  For signature
   calculation, the certificate is encoded using the ASN.1 distinguished
   encoding rules (DER) [X.208].  ASN.1 DER encoding is a tag, length,
   value encoding system for each element.

   Certificate  ::=  SEQUENCE  {
        tbsCertificate       TBSCertificate,
        signatureAlgorithm   AlgorithmIdentifier,
        signature
        signatureValue       BIT STRING  }

   TBSCertificate  ::=  SEQUENCE  {
        version         [0]  EXPLICIT Version DEFAULT v1,
        serialNumber         CertificateSerialNumber,
        signature            AlgorithmIdentifier,
        issuer               Name,
        validity             Validity,



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        subject              Name,
        subjectPublicKeyInfo SubjectPublicKeyInfo,
        issuerUniqueID  [1]  IMPLICIT UniqueIdentifier OPTIONAL,
                             -- If present, version must be v2 or v3
        subjectUniqueID [2]  IMPLICIT UniqueIdentifier OPTIONAL,
                             -- If present, version must be v2 or v3
        extensions      [3]  EXPLICIT Extensions OPTIONAL
                             -- If present, version must be v3
        }

   Version  ::=  INTEGER  {  v1(0), v2(1), v3(2)  }

   CertificateSerialNumber  ::=  INTEGER

   Validity ::= SEQUENCE {
        notBefore      Time,
        notAfter       Time }

   Time ::= CHOICE {
        utcTime        UTCTime,
        generalTime    GeneralizedTime }

   UniqueIdentifier  ::=  BIT STRING




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   SubjectPublicKeyInfo  ::=  SEQUENCE  {
        algorithm            AlgorithmIdentifier,
        subjectPublicKey     BIT STRING  }

   Extensions  ::=  SEQUENCE SIZE (1..MAX) OF Extension

   Extension  ::=  SEQUENCE  {
        extnID      OBJECT IDENTIFIER,
        critical    BOOLEAN DEFAULT FALSE,
        extnValue   OCTET STRING  }

   The following items describe a proposed use of the X.509 v3 certifi-
   cate certificate for use in the
   Internet.

4.1.1  Certificate Fields

   The Certificate is a SEQUENCE of three required fields. The fields
   are are described in detail in the following subsections subsections.

4.1.1.1  tbsCertificate

   The first field in the sequence is the tbsCertificate.  This is a
   itself a sequence, and contains the names of the subject and issuer, a public key
   associated with the subject an expiration date, subject, a validity period, and



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   information.  The fields of the basic tbsCertificate are described in detail in section 4.1.2;
   the tbscertificate may also include extensions which are described in
   section 4.2.

4.1.1.2  signatureAlgorithm

   The signatureAlgorithm field contains the algorithm identifier for the crypto-
   graphic algorithm used by the CA to sign this certificate.  Section
   7.2 lists the supported signature algorithms.

   An algorithm identifier is defined by the following ASN.1 structure:

   AlgorithmIdentifier  ::=  SEQUENCE  {
        algorithm               OBJECT IDENTIFIER,
        parameters              ANY DEFINED BY algorithm OPTIONAL  }

   and it

   The algorithm identifier is used to identify a cryptographic algorithm. algo-
   rithm.  The OBJECT IDENTIFIER algorithm component identifies the algorithm
   (such as RSA DSA with SHA-
   1).  In the sigantureAlgorithm field, the SHA-1).  The contents of the optional parameters
   field shall be will vary according to the value NULL. algorithm identified. Section 7.2
   lists the sup-
   ported supported algorithms for this specification.

   This field must contain the same algorithm identifier as the signa-
   ture field in the sequence tbsCertificate (see section 4.1.2.3) sec. 4.1.2.3).




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4.1.1.3  signature  signatureValue

   The signature signatureValue field contains a digital signature computed upon
   the ASN.1 DER encoded TBSCertificate. tbsCertificate.  The ASN.1 DER encoded TBSCertifi-
   cate tbsCer-
   tificate is used as the input to a one-way hash function.  The one-way
   hash function output value is encrypted (e.g., using RSA Encryption)
   to form the signed quantity.  This signature function. This signa-
   ture value is then ASN.1 encoded as a BIT STRING and included in the
   Certificate's signature field. The details of this process are specified speci-
   fied for each of the sup-
   ported supported algorithms in Section 7.2.

   By generating this signature, a CA certifies the validity of the
   information in tbscertificate. the tbsCertificate field.  In particular, the CA certifies cer-
   tifies the binding between the public key material and the subject of
   the certi-
   ficate. certificate.

4.1.2  TBSCertificate

   The sequence TBSCertificate is a sequence which contains information associated with the
   subject of the certificate and the CA who issued it.  Every TBSCertificate TBSCerti-
   ficate contains the names of the subject and issuer, a public key
   associated with the subject, an expiration date, a validity period, a version number number, and
   a serial number; some may contain optional



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   The remainder of this section describes the syntax and semantics of
   these fields.  A TBSCertificate may also include extensions.  Extensions  Exten-
   sions for the Internet PKI are described in Section 4.2.

4.1.2.1  Version

   This field describes the version of the encoded certificate.  When
   extensions are used, as expected in this profile, use X.509 version 3
   (value is 2).  If no extensions are present, but a UniqueIdentifier
   is present, use version 2 (value is 1).  If only basic fields are
   present, use version 1 (the value is omitted from the certificate as
   the default value).

   Implementations should be prepared to accept any version certificate.
   At a minimum, conforming implementations shall recognize version 3
   certificates.

   Generation of version 2 certificates is not expected by implementa-
   tions based on this profile.

4.1.2.2  Serial number

   The serial number is an integer assigned by the certification author-
   ity CA to each certificate. certifi-
   cate.  It must be unique for each certificate issued by a given CA
   (i.e., the issuer name and serial number iden-
   tify identify a unique certificate). certifi-
   cate).




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4.1.2.3  Signature

   This field contains the algorithm identifier for the algorithm used
   by the CA to sign the certificate.  Section 7.2 lists the supported
   signature algorithms.

   This field must contain the same algorithm identifier as the signa-
   tureAlgorithm field in the sequence Certificate (see section sec. 4.1.1.2).  As with signatureAlgorithm,
   The contents of the optional parameters component shall
   contain field will vary according to
   the value NULL. algorithm identified.  Section 7.2 lists the supported signature
   algorithms.

4.1.2.4  Issuer Name

   The issuer name field identifies the entity who has signed (and and issued the
   certificate).
   certificate.  The issuer identity may be carried in the issuer name
   field and/or the issuerAltName extension.  If identity information is
   present only in the issuerAltName extension, then the issuer name may
   be an empty sequence and the issuerAltName extension must be criti-
   cal.




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   Where it is non-null, the issuer name field shall contain an X.500 a non-null distinguished
   name (DN).  The issuer field is defined as the X.501 type Name.  Name
   is defined by the following ASN.1 structures:

   Name ::= CHOICE {
     RDNSequence }

   RDNSequence ::= SEQUENCE OF RelativeDistinguishedName

   RelativeDistinguishedName ::=
     SET OF AttributeTypeAndValue

   AttributeTypeAndValue ::= SEQUENCE {
     type     AttributeType,
     value    AttributeValue }

   AttributeType ::= OBJECT IDENTIFIER

   AttributeValue ::= ANY

   -- Directory string type -- DEFINED BY AttributeType

   DirectoryString ::= CHOICE {
         teletexString           TeletexString (SIZE (1..MAX), (1..MAX)),
         printableString         PrintableString (SIZE (1..MAX)),
         universalString         UniversalString (SIZE (1..MAX)),
         utf8String              UTF8String (SIZE (1.. MAX)),
         bmpString               BMPString (SIZE (1..MAX)) }

   The Name describes a hierarchical name composed of attributes, such
   as country name, and corresponding values, such as US.  The type of
   the component AttributeValue is determined by the AttributeType; in
   general it will be a directoryString. DirectoryString.

   The directoryString DirectoryString type is defined as a choice of PrintableString,
   TeletexString, BMPString UTF8String and UniversalString.  Conforming
   CAs shall  When



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   creating a distinguished name, including their own, conforming CAs
   shall choose from these options as follows:

      (a) if the character set is sufficient, the string will be
      represented as a PrintableString;

      (b) failing (a), if the bMPString BMPString character set is sufficient the
      string shall be represented as a BMPString; and

      (c) failing (a) and (b), if the UTF8 character set is sufficient,



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      UTF8String.

   The TeletexString and

      (d) failing (a), (b) UniversalString are included for backward com-
   patibility, and (c), should not be used for certificates for new subjects.
   However, these types may be used in certificates where the string shall name was
   previously established.  Certificate users should be represented as a
      UniversalString. prepared to
   receive certificates with these string types.

   Standard sets of attributes have been defined in the X.500 series of
   specifications.  Where CAs issue certificates with X.501 type names,
   it is recommended  This specification recommends that issuer names con-
   tain only the following attribute types: country, organization,
   organizational-unit, distinguished name qualifier, title, locality,
   state or province name, common name (e.g., "Susan Housley"), surname,
   given name, initials, and generationqualifier (e.g., "Jr." or "IV").
   The syntax and associated object identifiers (OIDs) for these attributes attri-
   bute types be used.

4.1.2.5  Validity

   This field indicates the period of validity of are provided in the certificate, ASN.1 modules in Appendices A and
   consists of two dates, B.

   Certificate users must be prepared to process the first issuer dis-
   tinguished name and last on which the certificate is
   valid.  The certificate validity period subject distinguished name (see sec. 4.1.2.6)
   fields to perform name chaining for certification path validation
   (see section 6). Name chaining is performed by matching the time interval during
   which the CA warrants that it will maintain information about issuer
   distinguished name in one certificate with the
   status subject name in
   another.

   This specification requires only a subset of the certificate, i.e. publish revocation data. name comparison
   functionality specified in X.501. The field is
   represented requirements for conforming
   implementations are as a SEQUENCE of two dates:  the date on which the certi-
   ficate validity period begins follows:

      (a) attribute values encoded in different string types (e.g.,
      PrintableString and BMPString) may be assumed to represent dif-
      ferent strings;

      (b) attribute values in string types other than PrintableString
      are case sensitive (this permits matching of attribute values as
      binary objects);

      (c) attribute values in PrintableString are not case sensitive
      (e.g., "Marianne Swanson" is the same as "MARIANNE SWANSON"); and



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      (d) attribute values in PrintableString are compared after remov-
      ing leading and trailing white space and converting internal
      strings of one or more consecutive white space characters to a
      single space.

   These name comparison rules permit a certificate user to validate
   certificates issued using languages or encodings unfamiliar to the
   certificate user.

4.1.2.5  Validity

   The certificate validity period is the time interval during which the
   CA warrants that it will maintain information about the status of the
   certificate. The field is represented as a SEQUENCE of two dates:
   the date on which the certificate validity period begins (notBefore)
   and the date on which the certificate validity period ends
   (notAfter).  Both notBefore and notAfter may be encoded as UTCTime or
   GeneralizedTime.

   CAs conforming to this profile shall always encode certificate vali-
   dity dates through the year 2049 as UTCTime; certificate validity
   dates in 2050 or later shall be encoded as GeneralizedTime.

4.1.2.5.1  UTCTime

   The universal time type, UTCTime, is a standard ASN.1 type intended
   for international applications where local time alone is not ade-
   quate.  UTCTime specifies the year through the two low order digits
   and time is specified to the precision of one minute or one second.
   UTCTime includes either Z (for Zulu, or Greenwich Mean Time) or a
   time differential.

   For the purposes of this profile, UTCTime values shall be expressed
   Greenwich Mean Time (Zulu) and shall include seconds (i.e., times are
   YYMMDDHHMMSSZ), even where the number of seconds is zero.  Conforming
   systems shall interpret the year field (YY) as follows:

      Where YY is greater than or equal to 50, the year shall be inter-
      preted as 19YY; and

      Where YY is less than 50, the year shall be interpreted as 20YY.

4.1.2.5.2  GeneralizedTime

   The generalized time type, GeneralizedTime, is a standard ASN.1 type
   for variable precision representation of time.  Optionally, the



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   GeneralizedTime Gen-
   eralizedTime field can include a representation of the time dif-
   ferential differen-
   tial between local and Greenwich Mean Time.



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   For the purposes of this profile, GeneralizedTime values shall be
   expressed Greenwich Mean Time (Zulu) and shall include seconds (i.e.,
   times are YYYYMMDDHHMMSSZ), even where the number of seconds is zero.
   GeneralizedTime values shall not include fractional seconds.

4.1.2.6  Subject Name

   The subject name field identifies the entity associated with the public
   key stored in the subject public key field.  The subject identity name may be
   carried in the subject field and/or the subjectAltName extension.  If
   identity
   the subject is a CA (e.g., the basic constraints extension, as dis-
   cussed in 4.2.1.10, is present and the value of cA is TRUE,) then the
   subject field must be populated with a non-null distinguished name
   matching the contents of the issuer field (see sec. 4.1.2.4) in all
   certificates issued by the subject CA.  If subject naming information
   is present only in the subjectAltName extension (e.g., a key bound
   only to an email address or URI), then the subject name may must be an
   empty sequence and the subjectAltName extension must be critical.

   Where it is non-null, non-empty, the subject name field shall contain an X.500
   distinguished dis-
   tinguished name (DN). The DN must be unique for each subject entity
   certified by the one CA as defined by the issuer name field. (A CA
   may issue more than one certificate with the same DN to the same subject sub-
   ject entity.)

   The subject name field is defined as the X.501 type Name, and shall
   follow the encoding rules for the issuer name field (see sec.
   4.1.2.4).

4.1.2.7  Subject Public Key Info

   This field is used to carry the public key and identify When encoding strings as the algorithm
   with type PrintableString, conform-
   ing CAs should use mixed case but should not include leading or
   trailing white space and should limit internal white space to sub-
   strings of a single space.

   Implementations of this specification should be prepared to receive
   the following X.501 attribute types: country, organization,
   organizational-unit, distinguished name qualifier, title, locality,
   state or province name, common name (e.g., "Susan Housley"), surname,
   given name, initials, and generationqualifier (e.g., "Jr." or "IV").
   The syntax and associated object identifiers (OIDs) for these attri-
   bute types are provided in the ASN.1 modules in Appendices A and B.

   Legacy implementations exist where an RFC 822 name is embedded in the
   subject distinguished name as a PKCS #9 EmailAddress attribute [PKCS
   #9].  Conforming implementations generating new certificates with
   electronic mail addresses must use the rfc822Name in the subject
   alternative name field (see sec. 4.2.1.7) to describe such identi-
   ties.  Simultaneous inclusion of the EmailAddress attribute in the
   subject distinugished name to support legacy implementations is
   deprecated but permitted.



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   The ASN.1 syntax for EmailAddress and the corresponding OID are sup-
   plied below.

   EmailAddress ::= IA5String

   pkcs-9 OBJECT IDENTIFIER ::=
          { iso(1) member-body(2) US(840) rsadsi(113549) pkcs(1) 9 }

   emailAddress OBJECT IDENTIFIER ::= { pkcs-9 1 }

4.1.2.7  Subject Public Key Info

   This field is used to carry the public key and identify the algorithm
   with which the key is used. The algorithm is identified using the
   algorithmIdentifier
   AlgorithmIdentifier structure specified in Section section 4.1.1.2. The
   object identifiers for the supported algorithms and the methods for
   encoding the public key materials (public key and parameters) are
   specified in Section section 7.3.

4.1.2.8  Unique Identifiers

   These fields may only appear if the version is 2 or 3 (see sec.
   4.1.2.1).  The subject and issuer unique identifier identifiers are present in
   the certifi-
   cate certificate to handle the possibility of reuse of subject and/or
   issuer names over time.  This profile recommends that names not be
   reused for different entities and that Internet certificates not make
   use of unique identifiers.  CAs conforming to this profile should not
   generate certificates with unique identifiers.  Applications conforming conform-
   ing to this profile should be capable of parsing unique identifiers
   and making comparisons.






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4.1.2.9  Extensions

   This field may only appear if the version number is 3 (see 4.1.2.x). sec. 4.1.2.1).
   If present, this field is a SEQUENCE of one or more certificate
   extensions. The format and content of certificate extensions in the
   Internet PKI is defined in Section section 4.2.

4.2  Standard Certificate Extensions

   The extensions defined for X.509 v3 certificates provide methods for
   associating additional attributes with users or public keys, keys and for
   managing the certification hierarchy, and for managing CRL distribu-
   tion. hierarchy.  The X.509 v3 certificate format for-
   mat also allows communities to define private extensions to carry
   information unique to those com-
   munities. communities.  Each extension in a certificate certi-
   ficate may be designated as crit-
   ical critical or non-critical.  A certificate
   using system (an application
   validating a certificate) must reject the certificate if it encounters a critical
   extension it does not recognize.  A non-
   critical recognize; however, a non-critical extension



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   may be ignored if it is not recognized.  The fol-
   lowing presents following sections
   present recommended extensions used within Internet certifi-
   cates certificates and
   standard locations for information.  Communities may elect to use
   additional extensions; however, caution should be exercised in
   adopting adopt-
   ing any critical extensions in certificates which might be used prevent use
   in a general context.

   Each extension includes an object identifier OID and an ASN.1 structure.  When an
   extension appears in a certificate, the object identifier OID appears as the field
   extnID and the corresponding ASN.1 encoded structure is the value of
   the octet string extnValue.  Only one instance of a particular extension exten-
   sion may appear in a particular certi-
   ficate. certificate. For example, a certificate certifi-
   cate may contain only one authority key identifier extension (4.2.1.1). (see
   sec. 4.2.1.1).  An extension may also include includes the
   optional boolean critical; critical's critical, with a
   default value is of FALSE.  The text for each extension specifies the
   acceptable values for the crit-
   ical critical field.

   Conforming CAs are required to support the key identifiers (see sec.
   4.2.1.1 and 4.2.1.2), basic Constraints exten-
   sion (Section constraints (see sec. 4.2.1.10), the key
   usage extension (4.2.1.3) (see sec. 4.2.1.3), and certi-
   ficate certificate policies extension (4.2.1.5). (see sec. 4.2.1.5)
   extensions. If the CA issues certificates with an empty sequence for
   the subject field, the CA must support the
   subjectAltName extension.  If the CA issues certificates with an
   empty sequence for the issuer field, the CA must support the
   issuerAltName extension. subject alternative name
   extension (see sec. 4.2.1.7).  Support for the remaining extensions
   is optional. Conforming CAs may support extensions that are not identi-
   fied iden-
   tified within this specification; certificate issuers are cautioned
   that marking such extensions as critical may inhibit interoperabil-
   ity.




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   At a minimum, applications conforming to this profile shall recognize
   the extensions which shall or may be critical. critical in this specification.
   These extensions are:  key usage (4.2.1.3), (see sec. 4.2.1.3), certificate policies (4.2.1.5), pol-
   icies (see sec. 4.2.1.5), the alternative sub-
   ject name (4.2.1.7), issuer subject alternative name (4.2.1.8), (see sec.
   4.2.1.7), basic con-
   straints (4.2.1.10), constraints (see sec. 4.2.1.10), name constraints (4.2.1.11),
   (see sec. 4.2.1.11), policy constraints
   (4.2.1.12), (see sec. 4.2.1.12), and
   extended key usage (4.2.1.14). (see sec. 4.2.1.13).

   In addition, this profile recommends application support for key
   identifiers
   (4.2.1.1 and 4.2.1.2), CRL distribution points (4.2.1.13), (see sec. 4.2.1.1 and
   authority information access (4.2.2.1). 4.2.1.2) extensions.

4.2.1  Standard Extensions

   This section identifies standard certificate extensions defined in
   [X.509] for use in the Internet Public Key Infrastructure. PKI.  Each extension is associated
   with an object identifier OID defined in [X.509].  These object identifiers OIDs are members of the certificateExtension certi-
   ficateExtension arc, which is defined by the following:

   certificateExtension  OBJECT IDENTIFIER ::=
                             {joint-iso-ccitt(2) ds(5) 29}



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   id-ce                 OBJECT IDENTIFIER ::=  certificateExtension

4.2.1.1  Authority Key Identifier

   The authority key identifier extension provides a means of identify-
   ing the public key corresponding to the particular private key used to sign a
   certificate. This extension would be is used where an issuer has multiple
   signing keys (either due to multiple concurrent key pairs or due to
   changeover).  In general, this extension should be
   included in certificates.  The identification can may be based on either the key identifier iden-
   tifier (the subject key identifier in the issuer's certificate) or on
   the issuer name and serial number.

   The keyIdentifier field of the authorityKeyIdentifier extension shall
   be included in all certificates generated by conforming CAs to facil-
   itate chain building. This profile recommends support for the key
   identifier method by all certificate users.  There is recommended one exception;
   where a CA distributes its public key in the form of a "self-signed"
   certificate, the authority key identifier may be omitted.  In this profile. Conforming CAs that generate this extension shall
   include or omit both authorityCertIssuer and authorityCertSerial-
   Number. If authorityCertIssuer and authorityCertSerialNumber are
   omitted,
   case, the keyIdentifier field shall subject and authority key identifiers would be present. identical.

   This extension shall not be marked critical.

   id-ce-authorityKeyIdentifier OBJECT IDENTIFIER ::=  { id-ce 35 }

   AuthorityKeyIdentifier ::= SEQUENCE {
        keyIdentifier             [0] KeyIdentifier           OPTIONAL,
        authorityCertIssuer       [1] GeneralNames            OPTIONAL,
        authorityCertSerialNumber [2] CertificateSerialNumber OPTIONAL



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    }

   KeyIdentifier ::= OCTET STRING

4.2.1.2  Subject Key Identifier

   The subject key identifier extension provides a means of identifying
   the particular public key used in an application.  Where a reference
   to a public key identifier is needed (as with an Authority Key Iden-
   tifier) and one is not This extension
   should be included in all certificates.

   To facilitate chain building, this extension MUST appear in all con-
   forming CA certificates, that is, all certificates including the associated certificate, a
   SHA-1 hash
   basic constraints extension (see sec. 4.2.1.10) where the value of cA
   is TRUE.  The value of the subject public key identifier shall be used.  The hash shall
   be calculated over the value (excluding tag and length)
   placed in the key identifier field of the BIT
   STRING subjectPublicKey in Authority Key Identifier
   extension (see sec. 4.2.1.1) of certificates issued by the subject of
   this certificate.

   Where a key identifier has not been previously established, this
   specification recommends the following method for generating



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   keyIdentifiers:  the keyIdentifier is composed of a four bit type
   field with the value 0100 followed by the least significant 60 bits
   of the SHA-1 hash of the BIT STRING subjectPublicKey.

   This extension should be marked non-critical.

   id-ce-subjectKeyIdentifier OBJECT IDENTIFIER ::=  { id-ce 14 }

   SubjectKeyIdentifier ::= KeyIdentifier

4.2.1.3  Key Usage

   The key usage extension defines the purpose (e.g., encipherment, sig-
   nature, certificate signing) of the key contained in the certificate.
   The usage restriction might be employed when a key that could be used
   for more than one operation is to be restricted.  For example, when
   an RSA key should be used only for signing, the digitalSignature and
   and/or nonRepudiation bits would be asserted. Likewise, when an RSA
   key should be used only for key management, the keyEncipherment bit
   would be asserted.  The profile recommends that when When used, this extension should be marked
   as a critical extension. criti-
   cal.

      id-ce-keyUsage OBJECT IDENTIFIER ::=  { id-ce 15 }

      KeyUsage ::= BIT STRING {
           digitalSignature        (0),
           nonRepudiation          (1),
           keyEncipherment         (2),
           dataEncipherment        (3),
           keyAgreement            (4),
           keyCertSign             (5),
           cRLSign                 (6),
           encipherOnly            (7),
           decipherOnly            (8) }


   Bits in the KeyUsage type are used as follows:

      The digitalSignature bit is asserted when the subject public key



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      is used to verifying verify digital signatures that have purposes other than
      non-repudiation, certificate signature, and CRL signature.  For
      example, The the digitalSignature bit is asserted when the subject
      public key is used to provide authentication.

      The nonRepudiation bit is asserted when the subject public key is
      used to verifying verify digital signatures used to provide a non-
      repudiation service which protects against the signing entity
      falsely denying some action, excluding certificate or CRL signing.



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      The keyEncipherment bit is asserted when the subject public key is
      used for key transport.  For example, when an RSA key is to be
      used exclusively for key management, then this bit must asserted.

      The dataEncipherment bit is asserted when the subject public key
      is used for enciphering user data, other than cryptographic keys.

      The keyAgreement bit is asserted when the subject public key is
      used for key agreement.  For example, when a Diffie-Hellman key is
      to be used exclusively for key management, then this bit must asserted.

      The keyCertSign bit is asserted when the subject public key is
      used for verifying a signature on certificates.  This bit may only
      be asserted in CA certificates.

      The cRLSign bit is asserted when the subject public key is used
      for verifying a signature on CRLs.  This bit may only be asserted
      in CA certificates.

      When revocation information (e.g., a CRL).

      The meaning of the encipherOnly bit is asserted and the undefined in the absence of
      the keyAgreement bit.  When the encipherOnly bit is asserted and
      the keyAgreement bit is also set, the subject public key may be
      used only for enciphering data while performing key agreement.

      The meaning of the enci-
      pherOnly decipherOnly bit is undefined in the absence of
      the keyAgreement bit.  When the decipherOnly bit is asserted and
      the keyAgreement bit is also set, the subject public key may be
      used only for deciphering data while performing key agreement.  The meaning of the deci-
      pherOnly bit is undefined in the absence of the keyAgreement bit.

   This profile does not restrict the combinations the of bits that may be
   set in an instantiation of the keyUsage extension.  However,
   appropriate values for keyUsage extensions for particular algo-
      rithms algorithms
   are specifed specified in section 7.3.







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4.2.1.4  Private Key Usage Period

   This profile recommends against the use of this extension.  CAs con-
   forming to this profile shall not generate certificates with critical
   private key usage period extensions.

   The private key usage period extension allows the certificate issuer
   to specify a different validity period for the private key than the
   certificate. This extension is intended for use with digital signa-
   ture keys.  This extension consists of two optional components notBe-
   fore components,
   notBefore and notAfter.  The private key associated with the certificate certifi-
   cate should not be used to sign objects before or after the times speci-
   fied
   specified by the two components, respectively. CAs conforming to this pro-
   file
   profile shall not generate certificates with private key usage period
   extensions unless at least one of the two components is present.

   This profile recommends against the use of this extension.  CAs con-
   forming to this profile shall not generate certificates with critical
   private key usage period extensions.



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   Where used, notBefore and notAfter are represented as GeneralizedTime
   and shall be specified and interpreted as defined in Section section
   4.1.2.5.2.

   id-ce-privateKeyUsagePeriod OBJECT IDENTIFIER ::=  { id-ce 16 }

   PrivateKeyUsagePeriod ::= SEQUENCE {
        notBefore       [0]     GeneralizedTime OPTIONAL,
        notAfter        [1]     GeneralizedTime OPTIONAL }

4.2.1.5  Certificate Policies

   The certificate policies extension contains a sequence of one or more
   policy information terms, each of which consists of an object iden-
   tifier (OID) and optional qualifiers.  These policy information terms
   indicate the policy under which the certificate has been issued and
   the purposes for which the certificate may be used.  This profile
   strongly recommends that a simple OID be present in this field.  Optional qualifiers qualif-
   iers, which may be present present, are not expected to provide
   information about obtaining CA rules, not change the definition
   of the policy.

   Applications with specific policy requirements are expected to have a
   list of those policies which they will accept and to compare the pol-
   icy OIDs in the certificate to that list.  If this extension is crit-
   ical, the path validation software must be able to interpret this
   extension,
   extension (including the optional qualifier), or must reject the certificate.  (Applications without
   specific cer-
   tificate.

   To promote interoperability, this profile recommends that policy requirements are not required to list acceptable pol-
   icies, and may accept any valid certificate regardless
   information terms consist of policy even
   if the extension only an OID.  Where an OID alone is marked critical.)
   insufficient, this profile strongly recommends that use of qualifiers
   be limited to those identified in this section.

   This specification defines two policy qualifiers qualifier types for use by
   certificate cer-
   tificate policy writers and certificate issuers at their own dis-
   cretion. issuers. The qualifier types
   are the CPS Pointer qualifier, and the



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INTERNET DRAFT                                            March 25, 1998 User Notice qualifier. qualifiers.

   The CPS Pointer qualifier contains a pointer to a Certification Prac-
   tice Statement (CPS) published by the CA.  The pointer is in the form
   of a URI.

   User notice is intended for display to a relying party when a certi-
   ficate is used.  The application software should display all user
   notices in all certificates of the certification path used, except
   that if a notice is duplicated only one copy need be displayed.  It
   is recommended that  To
   prevent such duplication, this qualifier should only the lowest-level certificate issued by one
   organization be present in a certification path contain a user notice.

   The user
   end-entity certificates and CA certificates issued to other organiza-
   tions.




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   The user notice has two optional fields: the noticeRef field and the
   explicitText field.

      The noticeRef field, if used, names an organization and identi-
      fies, by number, a particular textual statement prepared by that
      organization.  For example, it might identify the organization
      "CertsRUs" and notice number 1.  In a typical implementation, the
      application software will have a notice file containing the
      current set of notices for CertsRUs; the application will extract
      the notice text from the file and display it.  Messages may be
      multilingual, allowing the software to select the particular
      language message for its own environment.

      An explicitText field includes the textual statement directly in
      the certificate.  The explicitText field is a string with a max-
      imum size of 200 characters.

   If both the noticeRef and explicitText options are included in the
   one qualifier and if the application software can locate the notice
   text indicated by the noticeRef option then that text should be
   displayed; otherwise, the explicitText string should be displayed.

   id-ce-certificatePolicies OBJECT IDENTIFIER ::=  { id-ce 32 }

   certificatePolicies ::= SEQUENCE SIZE (1..MAX) OF PolicyInformation

   PolicyInformation ::= SEQUENCE {
        policyIdentifier   CertPolicyId,
        policyQualifiers   SEQUENCE SIZE (1..MAX) OF
                                PolicyQualifierInfo OPTIONAL }

   CertPolicyId ::= OBJECT IDENTIFIER

   PolicyQualifierInfo ::= SEQUENCE {
        policyQualifierId  PolicyQualifierId,



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        qualifier          ANY DEFINED BY policyQualifierId }

   -- policyQualifierIds for Internet policy qualifiers

   id-qt          OBJECT IDENTIFIER ::=  { id-pkix 2 }  -- pkix arc for qualifier types
   id-qt-cps      OBJECT IDENTIFIER ::=  { id-qt 1 }
   id-qt-unotice  OBJECT IDENTIFIER ::=  { id-qt 2 }

   PolicyQualifierId ::=
        OBJECT IDENTIFIER ( id-qt-cps | id-qt-unotice )

   Qualifier ::= CHOICE {
        cPSuri           CPSuri,



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        userNotice       UserNotice }

   CPSuri ::= IA5String

   UserNotice ::= SEQUENCE {
        noticeRef        NoticeReference OPTIONAL,
        explicitText     DisplayText OPTIONAL}

   NoticeReference ::= SEQUENCE {
        organization  IA5String,     DisplayText,
        noticeNumbers    SEQUENCE OF INTEGER }

   DisplayText ::= CHOICE {
        visibleString VisibleString,    VisibleString  (SIZE (1..200)),
        bmpString     BMPString,        BMPString      (SIZE (1..200)),
        utf8String       UTF8String     (SIZE (1..200)) }

4.2.1.6  Policy Mappings

   This extension is used in CA certificates.  It lists one or more
   pairs of object identifiers; OIDs; each pair includes an issuerDomainPolicy and a subjectDomainPolicy. sub-
   jectDomainPolicy. The pairing indicates the issuing CA con-
   siders considers its
   issuerDomainPolicy equivalent to the subject CA's sub-
   jectDomainPolicy. subjectDomainPol-
   icy.

   The issuing CA's users may accept an issuerDomainPolicy for certain
   applications. The policy mapping tells the issuing CA's users which
   policies associated with the subject CA are comparable to the policy
   they accept.

   This extension may be supported by CAs and/or applications, and it is
   always non-critical.

   id-ce-policyMappings OBJECT IDENTIFIER ::=  { id-ce 33 }



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   PolicyMappings ::= SEQUENCE SIZE (1..MAX) OF SEQUENCE {
        issuerDomainPolicy      CertPolicyId,
        subjectDomainPolicy     CertPolicyId }

4.2.1.7  Subject Alternative Name

   The subject alternative names extension allows additional identities
   to be bound to the subject of the certificate.  Defined options
   include an rfc822 name (electronic Internet electronic mail address), address, a DNS name, an IP
   address, and a URI. uniform resource indentifier (URI).  Other options
   exist, including completely local definitions.  Multiple instances of a name forms,
   and multiple instances of each name forms form, may be included.  Whenever
   such identities are to be bound into a certificate, the subject



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   alternative name (or issuer alternative name) extension shall be
   used.  (Note: a form of such an identifier may also be present in the
   subject distinguished name; however, the alternative name extension
   is the preferred location for finding such information.)

   Because the subject alternative name is considered to be defini-
   tiviely bound to the public key, all parts of the subject alternative
   name must be verified by the CA.  In addition, subject alternative
   names shall not include wildcard characters as a placeholder for a
   set of names.

   Further, if the only subject identity included in the certificate is
   an alternative name form (e.g., an electronic mail address), then the
   subject distinguished name shall be empty (an empty sequence), and
   the subjectAltName extension shall be present. If the subject field
   contains an empty sequence, the subjectAltName extension shall be
   marked critical.

   Where

   When the subjectAltName extension contains a uniformResourceIdentif-
   ier, an Internet mail address,
   the URI is a pointer to a sequence of certificates issued by
   this CA (and optionally other CAs) to this subject.

   The URI must adress shall be included as an absolute, rfc822Name. The format of an
   rfc822Name is an "addr-spec" as defined in RFC 822 [RFC 822]. An
   addr-spec has the form "local-part@domain". Note that an addr-spec
   has no phrase (such as a common name) before it, has no comment (text
   surrounded in parentheses) after it, and is not relative, pathname surrounded by "<" and must specify
   ">".

   When the host. This specification recognizes subjectAltName extension contains a iPAddress, the following values for address
   shall be stored in the
   URI scheme:  ftp, http, ldap, and mailto. octet string in "network byte order," as
   specified in RFC 791 [RFC 791]. The mailto scheme indi-
   cates that mail sent to least significant bit (LSB) of
   each octet is the specified address will generate an elec-
   tronic mail response (to LSB of the sender) containing the subject's certi-
   ficates.  No message is required.  If the URI scheme is ftp, then the
   information is available through anonymous ftp.  If the URI scheme is
   http or ldap, then the information may be retrieved using that proto-
   col.

   (If the URI specifies any other scheme, contains a relative pathname,
   or omits the  host, the semantics are not defined by this specifica-
   tion.)



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   When the subjectAltName extension contains a iPAddress, the address
   shall be stored in the octet string in "network byte order," as
   specified in RFC791. The least significant bit (LSB) of each octet is
   the LSB of the corresponding byte in corresponding byte in the network
   address. For IP Ver-
   sion Version 4, as specified in RFC 791, the octet string
   must contain exactly four octets.  For IP Version 6, as specified in
   RFC 1883, the octet string must contain exactly sixteen octets.

   Alternative octets [RFC
   1883].

   When the subjectAltName extension contains a domain name service
   label, the domain name shall be stored in the dNSName (an IA5String).
   The string shall be in the "preferred name syntax," as specified by
   RFC 1034 [RFC 1034]. Note that while upper and lower case letters are
   allowed in domain names, no signifigance is attached to the case.  In
   addition, while the string " " is a legal domain name, subjectAltName
   extensions with a dNSName " " are not permitted.  Finally, the use of
   the DNS representation for Internet mail addresses (wpolk.nist.gov
   instead of wpolk@nist.gov) is not permitted; such identities are to
   be encoded as rfc822Name.

   Subject alternative names may be constrained in the same manner as
   subject distinguished names using the name constraints extension as
   described in section 4.2.1.11.




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   If the subjectAltName extension is present, the sequence must contain
   at least one entry.  Unlike the subject field, conforming CAs shall
   not issue certificates with subjectAltNames containing empty General-
   Name fields. For example, an rfc822Name is represented as an
   IA5String. While an empty string is a valid IA5String, such an
   rfc822Name is not permitted by this profile.  The behavior of clients
   that encounter such a certificate when processing a certificication
   path is not defined by this profile.

   Finally, the semantics of subject alternative names that include
   wildcard characters (e.g., as a placeholder for a set of names) are
   not addressed by this specification.  Applications with specific
   requirements may use such names but must define the semantics.


      id-ce-subjectAltName OBJECT IDENTIFIER ::=  { id-ce 17 }

      SubjectAltName ::= GeneralNames

      GeneralNames ::= SEQUENCE SIZE (1..MAX) OF GeneralName

      GeneralName ::= CHOICE {
           otherName                       [0]     OtherName,
           rfc822Name                      [1]     IA5String,
           dNSName                         [2]     IA5String,
           x400Address                     [3]     ORAddress,
           directoryName                   [4]     Name,
           ediPartyName                    [5]     EDIPartyName,
           uniformResourceIdentifier       [6]     IA5String,
           iPAddress                       [7]     OCTET STRING,
           registeredID                    [8]     OBJECT IDENTIFIER}

      OtherName ::= SEQUENCE {
           type-id    OBJECT IDENTIFIER,
           value      [0] EXPLICIT ANY DEFINED BY type-id }

      EDIPartyName ::= SEQUENCE {
           nameAssigner            [0]     DirectoryString OPTIONAL,
           partyName               [1]     DirectoryString }






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4.2.1.8  Issuer Alternative Name Names

   As with 4.2.1.7, this extension is used to associate Internet style
   identities with the certificate issuer.  If the only issuer identity
   included in the certificate is an Issuer alternative name form (e.g., an
   electronic mail address), then the issuer distinguished name shall be
   empty (an empty sequence), and the issuerAltName extension shall be
   present. If the subject field contains an empty sequence, the
   issuerAltName extension shall be marked critical.

   Where the issuerAltName extension contains a URI, the following
   semantics names
   shall be assumed: the URI is a pointer to an ASN.1 sequence
   of certificates issued to this CA (and optionally other CAs).  The
   expected values for the URI are those defined encoded as in 4.2.1.7. Processing
   rules for other values are not defined by this specification.

   Where the issuerAltName present, this extension contains a dNSName, rfc822Name, or
   a URI, wildcard characters are should not permitted. be marked critical.




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      id-ce-issuerAltName OBJECT IDENTIFIER ::=  { id-ce 18 }

      IssuerAltName ::= GeneralNames

4.2.1.9  Subject Directory Attributes

   The subject directory attributes extension is not recommended as an
   essential part of this profile, but it may be used in local environ-
   ments.  This extension is always non-critical.

   id-ce-subjectDirectoryAttributes OBJECT IDENTIFIER ::=  { id-ce 9 }

   SubjectDirectoryAttributes ::= SEQUENCE SIZE (1..MAX) OF Attribute

4.2.1.10  Basic Constraints

   The basic constraints extension identifies whether the subject of the
   certificate is a CA and how deep a certification path may exist
   through that CA.

   The pathLenConstraint field is meaningful only if cA is set to TRUE.
   In this case, it gives the maximum number of CA certificates that may
   follow this certificate in a certification path. A value of zero
   indicates that only an end-entity certificate may follow in the path.
   Where it appears, the pathLenConstraint field must be greater than or
   equal to zero. Where pathLenConstraint does not appear, there is no
   limit to the allowed length of the certification path.

   This profile requires the use of this extension, and it extension shall always



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   be appear as a critical for extension in all CA certi-
   ficates.  This extension should not appear in other certificates.

   id-ce-basicConstraints OBJECT IDENTIFIER ::=  { id-ce 19 }

   BasicConstraints ::= SEQUENCE {
        cA                      BOOLEAN DEFAULT FALSE,
        pathLenConstraint       INTEGER (0..MAX) OPTIONAL }

4.2.1.11  Name Constraints

   The name constraints extension, which shall be used only in a CA cer-
   tificate, indicates a name space within which all subject names in
   subsequent certificates in a certification path must be located.
   Restrictions may apply to the subject distinguished name or subject
   alternative names.  Restrictions apply only when the specified name
   form is present. If no name of the type is in the certificate, the
   certificate is acceptable.

   Restrictions are defined in terms of permitted or excluded name



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   subtrees.  Any name matching a restriction in the excludedSubtrees
   field is invalid regardless of information appearing in the permittedSubtrees. permit-
   tedSubtrees.  This extension must be critical.

   Within this profile, the minimum and maximum fields are not used with
   any name forms, thus minimum is always zero, and maximum is always
   absent.

   Restrictions for the rfc822, dNSName, rfc822 and uri name forms are all expressed in
   terms of strings with wild card matching.  An "*" is the wildcard
   character.

   For uris and rfc822 names, URIs, the restriction constraint applies to the host part of the name.  Examples  Exam-
   ples would be foo.bar.com; www*.bar.com; and *.xyz.com.

   Legacy implementations exist where an RFC 822 name is embeded in the
   subject distinguished name as a PKCS #9 e-mail attribute, which has
   the ASN.1 type EmailAddress.  When rfc822 names are constrained, but
   the certificate does not include a subject alternative name, wild-
   card appears as the leftmost subdomain, it may be matched with one or
   more subdomains.  That is, the constraint "*.xyz.com" is satisfied by
   both abc.xyz.com and abc.def.xyz.com.  However, the constraint
   "*.xyz.com" is not satisfied by "xyz.com". Otherwise, the wildcard
   may only be expanded within a single subdomain. That is, www*.bar.com
   is satisfied by www1.bar.com but not www.foo.bar.com.

   To indicate all Internet mail addresses on a particular host, the "*"
   character is used. For example, "*@xyz.com" indicates all mail
   addresses at the host "xyz.com". Note that although "*" is a valid
   character in Internet mail addresses, it is very rarely used on the
   Internet, and thus is appropriated by this specification for the
   email wildcard.

   Internet mail addresses may also be constrained by the host part of
   the name, as with URIs.  For example, "root@*.xyz.com" indicates all
   the Internet mail addresses root in the domain "xyz.com".  As above,
   "*" is a valid character in the host part of the name, but it is very
   rarely used on the Internet, and thus is appropriated by this specif-
   ication for the mail address wildcard.

   To indicate all Internet mail addresses in a particular domain, these
   mechanisms may be combined.  For example, "*@*.xyz.com" indicates all
   email addresses in the domain "xyz.com".

   DNS name restrictions are expressed as foo.bar.com. Any DNS name that
   can be constructed by simply adding to the left hand side of the name
   satisfies the name constraint. For example, www.foo.bar.com would
   satisfy the constraint but foo1.bar.com would not.

   Legacy implementations exist where an RFC 822 name is embedded in the
   subject distinguished name as a PKCS #9 e-mail attribute, which has
   the ASN.1 type EmailAddress [PKCS #9] (see sec. 4.1.2.6). When rfc822
   names are constrained, but the certificate does not include a subject



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   alternative name, the rfc822 name constraint must be applied to PKCS
   #9 e-mail attributes in the subject distinguished name.  The ASN.1
   syntax for EmailAddress and the corresponding OID are supplied below.

   EmailAddress ::= IA5String

   pkcs-9 OBJECT IDENTIFIER ::=
          { iso(1) member-body(2) US(840) rsadsi(113549) pkcs(1) 9 }

   emailAddress OBJECT IDENTIFIER ::= { pkcs-9 1 } in
   4.1.2.6.

   Restrictions of the form directoryName shall be applied to the sub-
   ject field in the certificate and to the subjectAltName extensions of
   type directoryName. Restrictions of the form x400Address shall be
   applied to subjectAltName extensions of type x400Address.



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   The syntax of iPAddress shall be as described in section 4.2.1.7 with
   the following additions specifically for Name Constraints.  For IPv4
   addresses, the ipAddress field of generalName shall contain eight (8)
   octets, encoded in the style of RFC 1519 (CIDR) to represent an
   address range.  For IPv6 addresses, the ipAddress field shall contain
   32 octets similarly encoded.  For example, a name constraint for
   "class C" subnet 10.9.8.0 shall be represented as the octets 0A 09 08
   00 FF FF FF 00, representing the CIDR notation
   10.9.8.0/255.255.255.0.

   The syntax and semantics for name constraints for otherName, ediPar-
   tyName, iPAddress, and registeredID are not defined by this specifi-
   cation. specification.

      id-ce-nameConstraints OBJECT IDENTIFIER ::=  { id-ce 30 }

      NameConstraints ::= SEQUENCE {
           permittedSubtrees       [0]     GeneralSubtrees OPTIONAL,
           excludedSubtrees        [1]     GeneralSubtrees OPTIONAL }

      GeneralSubtrees ::= SEQUENCE SIZE (1..MAX) OF GeneralSubtree

      GeneralSubtree ::= SEQUENCE {
           base                    GeneralName,
           minimum         [0]     BaseDistance DEFAULT 0,
           maximum         [1]     BaseDistance OPTIONAL }

      BaseDistance ::= INTEGER (0..MAX)

4.2.1.12  Policy Constraints

   The policy constraints extension can be used in certificates issued
   to CAs. The policy constraints extension constrains path validation
   in two ways. It can be used to prohibit policy mapping or require
   that each certificate in a path contain an acceptable policy identif-
   ier.

   If the inhibitPolicyMapping field is present, the value indicates the
   number of additional certificates that may appear in the path before



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   policy mapping is no longer permitted.  For example, a value of one
   indicates that policy mapping may be processed in certificates issued
   by the subject of this certificate, but not in additional certifi-
   cates in the path.

   If the requireExplicitPolicy field is present, subsequent certifi-
   cates must include an acceptable policy identifier. The value of
   requireExplicitPolicy indicates the number of additional certificates
   that may appear in the path before an explicit policy is required.
   An acceptable policy identifier is the identifier of a policy
   required by the user of the certification path or the identifier of a
   policy which has been declared equivalent through policy mapping.

   Conforming CAs shall not issue certificates where policy constraints
   is a null sequence. That is, at least one of the inhibitPolicyMapping
   field or the requireExplicitPolicy field must be present. The
   behavior of clients that encounter a null policy constraints field is
   not addressed in this profile.




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   This extension may be critical or non-critical.

   id-ce-policyConstraints OBJECT IDENTIFIER ::=  { id-ce 36 }

   CertificatePoliciesSyntax ::=
                         SEQUENCE SIZE (1..MAX) OF PolicyInformation

   PolicyConstraints ::= SEQUENCE {
        requireExplicitPolicy           [0] SkipCerts OPTIONAL,
        inhibitPolicyMapping            [1] SkipCerts OPTIONAL }

   SkipCerts ::= INTEGER (0..MAX)

4.2.1.13  CRL Distribution Points

   The CRL distribution points extension identifies how CRL information
   is obtained.  The extension should be non-critical, but this profile
   recommends support  Extended key usage field

   This field indicates one or more purposes for this extension by CAs and applications.
   Further discussion of CRL management is contained in section 5.

   If the cRLDistributionPoints extension contains a Distribution-
   PointName of type URI, which the following semantics shall certified
   public key may be assumed: the
   URI is a pointer used, in addition to or in place of the current CRL for the associated reasons and
   will be issued by the associated cRLIssuer.  The expected values for basic pur-
   poses indicated in the URI are those key usage extension field.  This field is
   defined in 4.2.1.7. Processing rules for other
   values are not defined by this specification.  If the distribution-
   Point omits reasons, the CRL shall include revocations for all rea-
   sons. If the distributionPoint omits cRLIssuer, the CRL shall be
   issued by the CA that issued the certificate.

   id-ce-cRLDistributionPoints OBJECT IDENTIFIER ::=  { id-ce 31 }

   cRLDistributionPoints ::= {
        CRLDistPointsSyntax }

   CRLDistPointsSyntax ::= SEQUENCE SIZE (1..MAX) OF DistributionPoint

   DistributionPoint ::= SEQUENCE {
        distributionPoint       [0]     DistributionPointName OPTIONAL,
        reasons                 [1]     ReasonFlags OPTIONAL,
        cRLIssuer               [2]     GeneralNames OPTIONAL }

   DistributionPointName ::= CHOICE {
        fullName                [0]     GeneralNames,
        nameRelativeToCRLIssuer [1]     RelativeDistinguishedName }

   ReasonFlags ::= BIT STRING {
        unused                  (0),



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        keyCompromise           (1),
        cACompromise            (2),
        affiliationChanged      (3),
        superseded              (4),
        cessationOfOperation    (5),
        certificateHold         (6) }

4.2.1.14  Extended key usage field

   This field indicates one or more purposes for which the certified
   public key may be used, in addition to or in place of the basic pur-
   poses indicated in the key usage extension field.  This field is
   defined as follows:

   id-ce-extKeyUsage OBJECT IDENTIFIER ::= {id-ce 37}

   ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId

   KeyPurposeId ::= OBJECT IDENTIFIER

   Key purposes may be as follows:

   id-ce-extKeyUsage OBJECT IDENTIFIER ::= {id-ce 37}

   ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId

   KeyPurposeId ::= OBJECT IDENTIFIER

   Key purposes may be defined by any organization with a need. Object
   identifiers used to identify key purposes shall be assigned in accor-
   dance with IANA or ITU-T Rec. X.660 | ISO/IEC ISO/IEC/ITU 9834-1.



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   This extension may, at the option of the certificate issuer, be
   either critical or non-critical.

   If the extension is flagged critical, then the certificate shall be
   used only for one of the purposes indicated.

   If the extension is flagged non-critical, then it indicates the
   intended purpose or purposes of the key, and may be used in finding
   the correct key/certificate of an entity that has multiple
   keys/certificates. It is an advisory field and does not imply that
   usage of the key is restricted by the certification authority to the
   purpose indicated. (Using Certificate using applications may nevertheless
   require that a particular purpose be indicated in order for the certificate cer-
   tificate to be acceptable to that application.) application.

   If a certificate contains both a critical key usage field and a crit-
   ical extended key usage field, then both fields shall be processed
   independently and the certificate shall only be used for a purpose
   consistent with both fields.  If there is no purpose consistent with
   both fields, then the certificate shall not be used for any purpose.

   The following key usage purposes are defined by this profile:

   id-kp OBJECT IDENTIFIER ::= { id-pkix 3 }



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   id-kp-serverAuth              OBJECT IDENTIFIER ::=   {id-kp 1}
   -- TLS Web server authentication
   -- Key usage bits that may be consistent: digitalSignature,
   --                         keyEncipherment or keyAgreement
   --
   id-kp-clientAuth              OBJECT IDENTIFIER ::=   {id-kp 2}
   -- TLS Web client authentication
   -- Key usage bits that may be consistent: digitalSignature and/or
   --                            keyAgreement
   --
   id-kp-codeSigning             OBJECT IDENTIFIER ::=   {id-kp 3}
   -- Signing of downloadable executable code
   -- Key usage bits that may be consistent: digitalSignature
   --
   id-kp-emailProtection         OBJECT IDENTIFIER ::=   {id-kp 4}
   -- E-mail protection
   -- Key usage bits that may be consistent: digitalSignature,
   --                         nonRepudiation, and/or (keyEncipherment
   --                         or keyAgreement)
   --
   id-kp-ipsecEndSystem
   id-kp-timeStamping    OBJECT IDENTIFIER ::=   {id-kp 5} { id-kp 8 }
   -- IP security end system (host or router) Binding the hash of an object to a time from an agreed-upon time
   -- source. Key usage bits that may be consistent: digitalSignature and/or
   --                         (keyEncipherment or keyAgreement)
   --
   id-kp-ipsecTunnel             OBJECT IDENTIFIER ::=   {id-kp 6}
   -- IP security tunnel termination
   -- Key usage bits that may be consistent: digitalSignature and/or
   --                         (keyEncipherment or keyAgreement)
   --
   id-kp-ipsecUser               OBJECT IDENTIFIER ::=   {id-kp 7}
   -- IP security user
   -- Key usage bits that may be consistent: digitalSignature and/or
   --                         (keyEncipherment or keyAgreement)
   id-kp-timeStamping    OBJECT IDENTIFIER ::= { id-kp 8 }
   -- Binding the hash of an object to a time from an agreed-upon time
   -- source. Key usage bits that may be consistent: digitalSignature, digitalSignature,



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   --                         nonRepudiation

4.2.2  Private Internet Extensions

   This section defines one new

4.2.1.14  CRL Distribution Points

   The CRL distribution points extension identifies how CRL information
   is obtained.  The extension should be non-critical, but this profile
   recommends support for use this extension by CAs and applications.
   Further discussion of CRL management is contained in section 5.

   If the Internet Public
   Key Infrastructure.  This cRLDistributionPoints extension may be used to direct applica-
   tions to identify an on-line validation service supporting the issu-
   ing CA.  As contains a Distribution-
   PointName of type URI, the information may following semantics shall be available in multiple forms, each
   extension assumed: the
   URI is a sequence of IA5String values, each of which represents
   a URI.  The URI implicitly specifies pointer to the location and format of current CRL for the
   information associated reasons and
   will be issued by the method associated cRLIssuer.  The expected values for obtaining
   the information.



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   An object identifier is URI are those defined in 4.2.1.7. Processing rules for the private extension.  The
   object identifier associated with the private extension is other
   values are not defined
   under by this specification.  If the arc id-pe distribution-
   Point omits reasons, the CRL shall include revocations for all rea-
   sons. If the distributionPoint omits cRLIssuer, the CRL shall be
   issued by the CA that issued the certificate.

   id-ce-cRLDistributionPoints OBJECT IDENTIFIER ::=  { id-ce 31 }

   cRLDistributionPoints ::= {
        CRLDistPointsSyntax }

   CRLDistPointsSyntax ::= SEQUENCE SIZE (1..MAX) OF DistributionPoint

   DistributionPoint ::= SEQUENCE {
        distributionPoint       [0]     DistributionPointName OPTIONAL,
        reasons                 [1]     ReasonFlags OPTIONAL,
        cRLIssuer               [2]     GeneralNames OPTIONAL }

   DistributionPointName ::= CHOICE {
        fullName                [0]     GeneralNames,
        nameRelativeToCRLIssuer [1]     RelativeDistinguishedName }

   ReasonFlags ::= BIT STRING {
        unused                  (0),
        keyCompromise           (1),
        cACompromise            (2),
        affiliationChanged      (3),
        superseded              (4),
        cessationOfOperation    (5),
        certificateHold         (6) }

4.2.2  Private Internet Extensions

   This section defines one new extension for use in the Internet Public
   Key Infrastructure.  This extension may be used to direct



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   applications to identify an on-line validation service supporting the
   issuing CA.  As the information may be available in multiple forms,
   each extension is a sequence of IA5String values, each of which
   represents a URI.  The URI implicitly specifies the location and for-
   mat of the information and the method for obtaining the information.

   An object identifier is defined for the private extension.  The
   object identifier associated with the private extension is defined
   under the arc id-pe within the id-pkix name space.  Any future exten-
   sions defined for the Internet PKI will also be defined uder the arc
   id-pe.

      id-pkix  OBJECT IDENTIFIER  ::=
               { iso(1) identified-organization(3) dod(6) internet(1)
                       security(5) mechanisms(5) pkix(7) }

      id-pe  OBJECT IDENTIFIER  ::=  { id-pkix 1 }

4.2.2.1  Authority Information Access

   The authority information access extension indicates how to access CA
   information and services for the issuer of the certificate in which
   the extension appears. Information and services may include on-line
   validation services and CA policy data.  (The location of CRLs is not
   specified in this extension; that information is provided by the
   cRLDistributionPoints extension.)  This extension may be included in
   subject or CA certificates, and it is always non-critical.

   id-pe-authorityInfoAccess OBJECT IDENTIFIER ::= { id-pe 1 }

   AuthorityInfoAccessSyntax  ::=
           SEQUENCE SIZE (1..MAX) OF AccessDescription

   AccessDescription  ::=  SEQUENCE {
           accessMethod          OBJECT IDENTIFIER,
           accessLocation        GeneralName  }

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

   id-ad-ocsp OBJECT IDENTIFIER ::= { id-ad 1 }

   id-ad-caIssuers OBJECT IDENTIFIER ::= { id-ad 2 }

   Each entry in the sequence AuthorityInfoAccessSyntax describes the
   format and location of additional information about the CA who issued
   the certificate in which this extension appears.

   This profile defines an object identifier for  The type and format
   of the On-line Certificate
   Status Protocol (OCSP) that will be defined in [PKIXOCSP].  When id-
   ad-ocsp appears as accessMethod, information is specified by the accessMethod field; the
   accessLocation field describes specifies the on-line status server and location of the access protocol to obtain current
   certificate status information for information.  The
   retrieval mechanism may be implied by the certificate containing this
   extension. accessMethod or specified
   by accessLocation.



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   This profile defines an object identifier to obtain a description of one OID for accessMethod. 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 certi-
   ficate certificate user.

   When id-ad-caIssuers appears as accessMethod, accessInfoType, the accessLocation
   field describes the referenced description server and the access protocol pro-
   tocol to obtain the referenced description.

   Additional access descriptors will likely be  The accessLocation field
   is defined in as a GeneralName, which can take several forms.  Where the future.

   The authorityInfoAccess extension may
   information is available via http, ftp, or ldap, accessLocation shall
   be included in a PKCS 7 encap-
   sulation as an X.501 ATTRIBUTE.  This attribute can then uniformResourceIdentifier.  Where the information is available
   via the directory access protocol (dap), accessLocation shall be used to
   locate certificates automatically rather than include a
   directoryName. When the certifi-
   cates directly. information is available via electronic mail,
   accessLocation shall be an rfc822Name.  The intended effect semantics of other name
   forms of accessLocation (when accessMethod is id-ad-caIssuers) are
   not defined by this specification.

   Additional access descriptors may be defined in other PKIX specifica-
   tions.

5  CRL and CRL Extensions Profile

   As described above, one goal of this X.509 v2 CRL profile is to reduce
   foster the size creation of the
   encapsulated message or object.

   PKCS 9 identifies attributes an interoperable and reusable Internet PKI.
   To achieve this goal, guidelines for inclusion in PKCS 7, referencing
   X.520 standard attributes the use of extensions are speci-
   fied, and defining additional attributes unique
   to PKCS 9. The attributes defined in X.520 some assumptions are based on made about the defini-
   tion nature of ATTRIBUTE information
   included in ITU-T X.501 | ISO/IEC 9594-2.

   The following syntax defines authorityInfoAccess as an ATTRIBUTE
   suitable for inclusion in a PKCS #7 message:

   authorityInfoAccess ATTRIBUTE ::= {
       WITH SYNTAX    authorityInfoAccessSyntax,
       ID             id-pe-authorityInfoAccess }

   Other parts of the PKIX specifications [PKIXOCSP] [PKIXLDAP] estab-
   lish requirements on certificate retrieval mechanisms. It is expected
   that applications using the URI form of the authorityInfo field for
   such a purpose will:

   1.  Prepend a suitable HTTP retrieval primitive to the URL (e.g.
   "GET").

   2.  Append a filename to the URL.

   3.  Use the result to retrieve a file containing the requested certi-
   ficate.

   4.  Use the authorityInfoAccess extension in that and subsequent cer-
   tificates to complete a certificate path.

   The filename will be formed as the IA5string representation of
   SHA1(Issuer DN | certificate serial number) concatenated with ".cer."
   The IA5String representation will display the SHA1 result as a



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   hexidecimal number using digits and the lowercase letters 'a' through
   'f.'  The SignerInfo syntax of PKCS 7 provides the necessary informa-
   tion as issuerAndSerialNumber.

   The specified file will contain a single DER encoded certficate.

5  CRL and CRL Extensions Profile

   As described above, one goal of this X.509 v2 CRL profile is to
   foster the creation of an interoperable and reusable Internet PKI.
   To achieve this goal, guidelines for the use of extensions are speci-
   fied, and some assumptions are made about the nature of information
   included in the CRL.

   CRLs may be used the CRL.

   CRLs may be used in a wide range of applications and environments
   covering a broad spectrum of interoperability goals and an even
   broader spectrum of operational and assurance requirements.  This
   profile establishes a common baseline for generic applications
   requiring broad interoperability.  Emphasis is placed on support for
   X.509 v2 CRLs.  The profile defines a baseline set
   of information that can be expected in every CRL.  Also, the profile
   defines common locations within the CRL for frequently used attributes, and attri-
   butes as well as common representations for these attributes.

   This profile does not define any private Internet CRL extensions or
   CRL entry extensions.

   Environments with additional or special purpose requirements may
   build on this profile or may replace it.

   Conforming CAs are not required to issue CRLs if other revocation or
   certificate status mechanisms are provided.  Conforming CAs that
   issue CRLs are required to issue version 2 CRLs, and CAs must include



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   the date by which the next CRL will be issued in the nextUpdate field (Section
   (see sec. 5.1.2.5).  Conforming applications are required to process
   version 1 and 2 CRLs.

5.1  CRL Fields

   The X.509 v2 CRL syntax is as follows.  For signature calculation,
   the data that is to be signed is ASN.1 DER encoded.  ASN.1 DER encod-
   ing is a tag, length, value encoding system for each element.

   CertificateList  ::=  SEQUENCE  {
        tbsCertList          TBSCertList,
        signatureAlgorithm   AlgorithmIdentifier,
        signature
        signatureValue       BIT STRING  }




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   TBSCertList  ::=  SEQUENCE  {
        version                 Version OPTIONAL,
                                     -- if present, must be v2
        signature               AlgorithmIdentifier,
        issuer                  Name,
        thisUpdate              Time,
        nextUpdate              Time OPTIONAL,
        revokedCertificates     SEQUENCE OF SEQUENCE  {
             userCertificate         CertificateSerialNumber,
             revocationDate          Time,
             crlEntryExtensions      Extensions OPTIONAL
                                           -- if present, must be v2
                                  }  OPTIONAL,
        crlExtensions           [0]  EXPLICIT Extensions OPTIONAL
                                           -- if present, must be v2
                                  }

   -- Version, Time, CertificateSerialNumber CertificateSerialNumber, and Extensions
   -- are all defined in the ASN.1 in section 4.1

   AlgorithmIdentifier  ::=  SEQUENCE  {
        algorithm               OBJECT IDENTIFIER,
        parameters              ANY DEFINED BY algorithm OPTIONAL  }

   -- contains a value of AlgorithmIdentifier is defined in section 4.1.1.2

   The following items describe the type
                                -- registered for use with the
                                -- algorithm object identifier value


   The following items describe the proposed use of the X.509 v2 CRL in the
   Internet PKI.

5.1.1  CertificateList Fields

   The CertificateList is a SEQUENCE of three required fields. The
   fields are are described in detail in the following subsections subsections.







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5.1.1.1  tbsCertList

   The first field in the sequence is the tbsCertList.  This field is
   itself a sequence containing the name of the issuer, issue date,
   issue date of the next list, the list of revoked certificates, and
   optional CRL extensions.  Further, each entry on the revoked certifi-
   cate list is defined by a sequence of user certificate serial number,
   revocation date, and optional CRL entry extensions.







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5.1.1.2  signatureAlgorithm

   The signatureAlgorithm field contains the algorithm identifier for
   the algorithm used by the CA to sign the CertificateList.  In the
   sigantureAlgorithm field, the contents of the optional parameters  The field shall be the value NULL.
   is of type AlgorithmIdentifier, which is defined in section 4.1.1.2.
   Section 7.2 lists the supported algo-
   rithms algorithms for this specification.
   Conforming CAs shall use the algo-
   rithm algorithm identifiers presented in Section sec-
   tion 7.2 when signing with a sup-
   ported supported signature algorithm.

   This field must contain the same algorithm identifier as the signa-
   ture field in the sequence tbsCertList (see sec. 5.1.2.2).

5.1.1.3  signature  signatureValue

   The signature signatureValue field contains a digital signature computed upon
   the ASN.1 DER encoded TBSCertList. tbsCertList.  The ASN.1 DER encoded  TBSCertList tbsCertList
   is used as the input to a one-way hash function.  The one-way hash func-
   tion output value is encrypted (e.g., using RSA Encryption) to form the signed quantity. signature function. This signature value
   is then ASN.1 encoded as a BIT STRING and included in the CRL's signature sig-
   natureValue field. The details of this process are specified for each
   of the supported algorithms in
   Section section 7.2.

5.1.2  Certificate List "To Be Signed"

   The certificate list to be signed, or tBSCertList, TBSCertList, is a SEQUENCE of
   required and optional fields.  The required fields identify the CRL
   issuer, the algorithm used to sign the CRL, the date and time the CRL
   was issued, and the date and time by which the CA will issue the next
   CRL.

   Optional fields include lists of revoked certificates and CRL exten-
   sions.  The revoked certificate list is optional to support the spe-
   cial case
   where a CA has not revoked any unexpired certificates that it has
   issued.  It is expected that nearly all CRLs issued in the Inter-
   net PKI will contain one or more lists of revoked certificates.
   Similarly, the  The profile requires conforming CAs to use the CRL exten-
   sion extension
   cRLNumber in all CRLs issued.

5.1.2.1  Version

   This optional field describes the version of the encoded CRL.  When
   extensions are used, as expected in required by this profile, this field shall be



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   present and shall specify version 2 (the integer value is 1).  If
   neither CRL extensions nor CRL entry extensions are present, version
   1 CRLs are recommended. In this case, the field shall be ommitted.







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5.1.2.2  Signature

   This field contains the algorithm identifier for the algorithm used
   to sign the CRL.  Section 7.2 lists OIDs for the most popular signa-
   ture algorithms used in the Internet PKI.

   This field must contain the same algorithm identifier as the signa-
   tureAlgorithm field in the sequence CertificateList (see section
   5.1.1.2).  As with signatureAlgorithm, the parameters component shall
   contain the value NULL.

5.1.2.3  Issuer Name

   The issuer name identifies the entity who has signed (and and issued the
   CRL).
   CRL.  The issuer identity may be is carried in the issuer name field
   and/or the issuerAltName extension.  If identity information is
   present only in the issuerAltName extension, then the issuer field. Alter-
   native name forms may
   be an empty sequence and also appear in the issuerAltName extension must be criti-
   cal.

   Where it is non-null, the (see
   sec. 5.2.2).  The issuer name field shall contain an X.500
   distinguished dis-
   tinguished name (DN).  The issuer name field is defined as the X.501
   type Name, and shall follow the encoding rules for the issuer name
   field in the certificate (see sec. 4.1.2.4).

5.1.2.4  This Update

   This field indicates the issue date of this CRL. ThisUpdate may be
   encoded as UTCTime or GeneralizedTime.

   CAs conforming to this profile that issue CRLs shall encode thisUp-
   date as UTCTime for dates through the year 2049. CAs conforming to
   this profile that issue CRLs shall encode thisUpdate as Generalized-
   Time for dates in the year 2050 or later.

   Where encoded as UTCTime, thisUpdate shall be specified and inter-
   preted as defined in Section section 4.1.2.5.1.  Where encoded as General-
   izedTime, thisUpdate shall be specified and interpreted as defined in
   Section
   section 4.1.2.5.2.

5.1.2.5  Next Update

   This field indicates the date by which the next CRL will be issued.
   The next CRL could be issued before the indicated date, but it will
   not be issued any later than the indicated date. nextUpdate may be
   encoded as UTCTime or GeneralizedTime.

   This profile requires inclusion of nextUpdate in all CRLs issued by



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   conforming CAs. Note that the ASN.1 syntax of TBSCertList describes
   this field as OPTIONAL, which is consistent with the ASN.1 structure
   defined in [X.509]. The behavior of clients processing CRLs which



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   omit nextUpdate is not specified by this profile.

   CAs conforming to this profile that issue CRLs shall encode nextUp-
   date as UTCTime for dates through the year 2049. CAs conforming to
   this profile that issue CRLs shall encode nextUpdate as Generalized-
   Time for dates in the year 2050 or later.

   Where encoded as UTCTime, nextUpdate shall be specified and inter-
   preted as defined in Section section 4.1.2.5.1.  Where encoded as General-
   izedTime, nextUpdate shall be specified and interpreted as defined in
   Section
   section 4.1.2.5.2.

5.1.2.6  Revoked Certificates

   Revoked certificates are listed.  The revoked certificates are named
   by their serial numbers.  Certificates are uniquely identified by the
   combination of the issuer name or issuer alternative name along with
   the user certificate serial number.  The date on which the revocation
   occurred is specified.  The time for revocationDate shall be
   expressed as described in section 5.1.2.4. Additional information may
   be supplied in CRL entry extensions; CRL entry extensions are dis-
   cussed in section 5.3.

5.1.2.7  Extensions

   This field may only appear if the version number is 2 (see sec. 5.1.2.1).
   If present, this field is a SEQUENCE of one or more CRL extensions.
   CRL extensions are discussed in section 5.2.

5.2  CRL Extensions

   The extensions defined by ANSI X9 and ISO ISO/IEC/ITU for X.509 v2 CRLs
   [X.509] [X9.55] provide methods for associating additional attributes
   with CRLs.  The X.509 v2 CRL format also allows communities to define
   private extensions to carry information unique to those communities.
   Each extension in a CRL may be designated as critical or non-
   critical.  A CRL validation must fail if it encounters an a critical
   extension which it does not know how to process.  However, an
   unrecognized non-critical extension may be ignored.  The following
   presents
   subsections present those extensions used within Internet CRLs.  Communities  Com-
   munities may elect to include extensions in CRLs which are not
   defined in this specification. However, caution should be exercised
   in adopting any critical extensions in CRLs which might be used in a
   general context.

   Conforming CAs that issue CRLs are required to support include the authority
   key identifier (see sec. 5.2.1) and the CRL number (see sec. 5.2.3)
   extensions in all CRLs issued.



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   extension (5.2.3), and include it in all CRLs issued. Conforming
   applications are required to support the critical and optionally
   critical CRL extensions issuer alternative name (5.2.2), issuing dis-
   tribution point (5.2.4) and delta CRL indicator (5.2.5).


5.2.1  Authority Key Identifier

   The authority key identifier extension provides a means of identify-
   ing the particular public key corresponding to the private key used to sign a
   CRL.  The identification can be based on either the key identifier
   (the subject key identifier in the CRL signer's certificate) or on
   the issuer name and serial number.  The key identifier method is recommended in this profile. This extension would be used is especially use-
   ful where an issuer has multiple more than one signing
   keys, key, either due to multiple mul-
   tiple concurrent key pairs or due to change-
   over.  In general, changeover.

   Conforming CAs shall use the key identifier method, and shall include
   this non-critical extension should be included in
   certificates. all CRLs issued.

   The syntax for this CRL extension is defined in Section section 4.2.1.1.

5.2.2  Issuer Alternative Name

   The issuer alternative names extension allows additional identities
   to be associated with the issuer of the CRL.  Defined options include
   an rfc822 name (electronic mail address), a DNS name, an IP address,
   and a URI.  Multiple instances of a name and multiple name forms may
   be included.  Whenever such identities are used, the issuer alterna-
   tive name extension shall be used.

   Further, if the only issuer identity included in the CRL is an alter-
   native name form (e.g., an electronic mail address), then the issuer
   distinguished name should be empty (an empty sequence), the

   The issuerAltName extension should be used, and the issuerAltName exten-
   sion must not be marked critical.

   The object identifier OID and syntax for this CRL extension are defined in Section section
   4.2.1.8.

5.2.3  CRL Number

   The CRL number is a non-critical CRL extension which conveys a mono-
   tonically increasing sequence number for each CRL issued by a given
   CA through a specific CA X.500 Directory entry or CRL distribution
   point. CA.
   This extension allows users to easily determine when a par-
   ticular particular CRL
   supersedes another CRL.  CAs conforming to this profile shall include
   this extension in all CRLs.

   id-ce-cRLNumber OBJECT IDENTIFIER ::= { id-ce 20 }




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   cRLNumber ::= INTEGER (0..MAX)

5.2.4  Issuing Distribution Point  Delta CRL Indicator

   The issuing distribution point delta CRL indicator is a critical CRL extension that iden-
   tifies the CRL distribution point identifies a
   delta-CRL.  The use of delta-CRLs can significantly improve process-
   ing time for applications which store revocation information in a particular CRL, and it
   format other than the CRL structure.  This allows changes to be added
   to the local database while ignoring unchanged information that is



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   already in the local database.

   When a delta-CRL is issued, the CAs shall also issue a complete CRL.

   The value of BaseCRLNumber identifies the CRL number of the base CRL
   that was used as the starting point in the generation of this delta-
   CRL.  The delta-CRL contains the changes between the base CRL and the
   current CRL issued along with the delta-CRL.  It is the decision of a
   CA as to whether to provide delta-CRLs.  Again, a delta-CRL shall not
   be issued without a corresponding complete CRL.  The value of
   CRLNumber for both the delta-CRL and the corresponding complete CRL
   shall be identical.

   A CRL user constructing a locally held CRL from delta-CRLs shall con-
   sider the constructed CRL incomplete and unusable if the CRLNumber of
   the received delta-CRL is more that one greater that the CRLnumber of
   the delta-CRL last processed.

   id-ce-deltaCRLIndicator OBJECT IDENTIFIER ::= { id-ce 27 }

   deltaCRLIndicator ::= BaseCRLNumber

   BaseCRLNumber ::= CRLNumber

5.2.5  Issuing Distribution Point

   The issuing distribution point is a critical CRL extension that iden-
   tifies the CRL distribution point for a particular CRL, and it indi-
   cates whether the CRL covers revocation for end entity certificates
   only, CA  certificates only, or a limitied set of reason codes.  Since
   this
   Although the extension is critical, all certificate users must be prepared conforming implementations are
   not required to
   receive CRLs with support this extension.

   The CRL is signed using the CA's private key.  CRL Distribution
   Points do not have their own key pairs.  If the CRL is stored in the
   X.500 Directory, it is stored in the Directory entry corresponding to
   the CRL distribution point, which may be different than the Directory
   entry of the CA.

   CAs may use CRL distribution points to partition the CRL on the basis
   of compromise and routine revocation.  In this case, the revocations
   with reason code keyCompromise (1) shall appear in one distribution
   point, and the revocations with other reason codes shall appear in
   another distribution point. The reason codes associated with a dis-
   tribution point must be specified in onlySomeReasons. If onlySomeRea-
   sons does not appear, the distribution point must contain revocations
   for all reason codes.




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   Where the issuingDistributionPoint extension contains a URL, the fol-
   lowing semantics shall be assumed: the object is a pointer to the
   most current CRL issued by this CA.  The URI schemes ftp, http,
   mailto [RFC1738] and ldap [RFC1778] are defined for this purpose.
   The URI must be an absolute, not relative, pathname and must specify
   the host.

   id-ce-issuingDistributionPoint OBJECT IDENTIFIER ::= { id-ce 28 }

   issuingDistributionPoint ::= SEQUENCE {
        distributionPoint       [0] DistributionPointName OPTIONAL,
        onlyContainsUserCerts   [1] BOOLEAN DEFAULT FALSE,
        onlyContainsCACerts     [2] BOOLEAN DEFAULT FALSE,
        onlySomeReasons         [3] ReasonFlags OPTIONAL,
        indirectCRL             [4] BOOLEAN DEFAULT FALSE }

5.2.5  Delta

5.3  CRL Indicator Entry Extensions

   The delta CRL indicator is a critical CRL extension that identifies a
   delta-CRL.  The use of delta-CRLs can significantly improve process-
   ing time entry extensions already defined by ANSI X9 and ISO/IEC/ITU
   for applications which store revocation information in a
   format other than the X.509 v2 CRLs provide methods for associating additional attri-
   butes with CRL structure.  This entries [X.509] [X9.55].  The X.509 v2 CRL format also
   allows changes communities to be added



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   information that is
   already unique to those communities.  Each extension in the local database.

   When a delta-CRL is issued, the CAs shall also issue a complete CRL.

   The value of BaseCRLNumber identifies the CRL number of the base CRL
   that was used
   entry may be designated as the starting point in the generation of this delta-
   CRL.  The delta-CRL contains the changes between the base CRL and the
   current critical or non-critical.  A CRL issued along with the delta-CRL.  It is the decision of a
   CA as to whether to provide delta-CRLs.  Again, valida-
   tion must fail if it encounters a delta-CRL shall critical CRL entry extension which
   it does not know how to process.  However, an unrecognized non-
   critical CRL entry extension may be issued without a corresponding CRL. ignored.  The value of CRLNumber for
   both the delta-CRL following subsec-
   tions present recommended extensions used within Internet CRL entries
   and the corresponding standard locations for information.  Communities may elect to use
   additional CRL shall entry extensions; however, caution should be identical.

   A exercised
   in adopting any critical extensions in CRL user constructing entries which might be
   used in a locally held CRL from delta-CRLs shall con-
   sider the constructed general context.

   All CRL incomplete and unusable if the CRLNumber of
   the received delta-CRL entry extensions used in this specification are non-critical.
   Support for these extensions is more optional for conforming CAs and
   applications.  However, CAs that one greater issue CRLs are strongly encouraged
   to include reason codes (see sec. 5.3.1) and invalidity dates (see
   sec. 5.3.3) whenever this information is available.

5.3.1  Reason Code

   The reasonCode is a non-critical CRL entry extension that identifies
   the CRLnumber reason for the certificate revocation. CAs are strongly
   encouraged to include meaningful reason codes in CRL entries; how-
   ever, the reason code CRL entry extension should be absent instead of
   using the delta-CRL last processed.

   id-ce-deltaCRLIndicator unspecified (0) reasonCode value.

   id-ce-cRLReason OBJECT IDENTIFIER ::= { id-ce 27 21 }

   deltaCRLIndicator



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   -- reasonCode ::= BaseCRLNumber

   BaseCRLNumber { CRLReason }

   CRLReason ::= CRLNumber

5.2.6 Certificate Issuer

   This ENUMERATED {
        unspecified             (0),
        keyCompromise           (1),
        cACompromise            (2),
        affiliationChanged      (3),
        superseded              (4),
        cessationOfOperation    (5),
        certificateHold         (6),
        removeFromCRL           (8) }

5.3.2  Hold Instruction Code

   The hold instruction code is a non-critical CRL entry extension identifies that
   provides a registered instruction identifier which indicates the certificate issuer associated
   with an entry in an indirect CRL, i.e.
   action to be taken after encountering a CRL certificate that has the indirectCRL
   indicator set in its issuing distribution point extension. If been
   placed on hold.

   id-ce-holdInstructionCode OBJECT IDENTIFIER ::= { id-ce 23 }

   holdInstructionCode ::= OBJECT IDENTIFIER

   The following instruction codes have been defined.  Conforming appli-
   cations that process this extension is not present on the first entry in an indirect CRL, the
   certificate issuer defaults to shall recognize the CRL issuer. On subsequent entries
   in an indirect CRL, if this extension is not present, the certificate
   issuer for the entry is the same as that for the preceding entry.
   This field is defined as follows:

   id-ce-certificateIssuer following
   instruction codes.

   holdInstruction    OBJECT IDENTIFIER ::=
                    { id-ce 29 iso(1) member-body(2) us(840) x9-57(10040) 2 }

   certificateIssuer

   id-holdinstruction-none   OBJECT IDENTIFIER ::=     GeneralNames

   If used by conforming CAs that issue CRLs, this extension is always
   critical. {holdInstruction 1}
   id-holdinstruction-callissuer
                             OBJECT IDENTIFIER ::= {holdInstruction 2}
   id-holdinstruction-reject OBJECT IDENTIFIER ::= {holdInstruction 3}

   Conforming applications  if which encounter an implementation ignored this
   extension it could not correctly attribute CRL entries to id-holdinstruction-
   callissuer must call the certificate issuer or reject the certifi-
   cates.

5.3  CRL Entry Extensions
   cate.  Conforming applications which encounter an id-
   holdinstruction-reject shall reject the certificate. The CRL entry extensions already defined by ANSI X9 hold
   instruction id-holdinstruction-none is semantically equivalent to the
   absence of a holdInstructionCode, and ISO for X.509
   v2 CRLs [X.509] [X9.55] provide methods its use is strongly deprecated
   for associating additional the Internet PKI.

5.3.3  Invalidity Date

   The invalidity date is a non-critical CRL entry extension that pro-
   vides the date on which it is known or suspected that the private key
   was compromised or that the certificate otherwise became invalid.



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   attributes with CRL entries.  The X.509 v2 CRL format also allows
   communities to define private CRL entry extensions to carry informa-
   tion unique to those communities.  Each extension in a CRL entry


   This date may be designated as critical or non-critical.  A CRL validation must
   fail if it encounters a critical earlier than the revocation date in the CRL entry extension entry,
   which it does
   not know how to process.  However, an unrecognized non-critical CRL
   entry extension may be ignored.  The following presents recommended
   extensions used within Internet CRL entries and standard locations
   for information.  Communities may elect to use additional CRL entry
   extensions; however, caution should be exercised in adopting any
   critical extensions in CRL entries is the date at which might be used in the CA processed the revocation. When a general
   context.

   All CRL entry extensions are non-critical; support for these exten-
   sions
   revocation is optional for conforming CAs and applications.  However, CAs
   that first posted by a CA in a CRL, the invalidity date may
   precede the date of issue CRLs are strongly encouraged to include reason codes
   (5.3.1) whenever of earlier CRLs, but the revocation date
   should not precede the date of issue of earlier CRLs.  Whenever this
   information is available.

5.3.1  Reason Code

   The reasonCode is a non-critical CRL entry extension that identifies
   the reason for the certificate revocation. available, CAs are strongly encouraged to include reason codes in CRL entries; however, the rea-
   son code share it
   with CRL entry extension should users.

   The GeneralizedTime values included in this field shall be absent instead of using the
   unspecified (0) reasonCode value.

   id-ce-cRLReason expressed
   in Greenwich Mean Time (Zulu), and shall be specified and interpreted
   as defined in section 4.1.2.5.2.

   id-ce-invalidityDate OBJECT IDENTIFIER ::= { id-ce 21 }

   -- reasonCode ::= { CRLReason 24 }

   CRLReason

   invalidityDate ::= ENUMERATED {
        unspecified             (0),
        keyCompromise           (1),
        cACompromise            (2),
        affiliationChanged      (3),
        superseded              (4),
        cessationOfOperation    (5),
        certificateHold         (6),
        removeFromCRL           (8) }

5.3.2  Hold Instruction Code

   The hold instruction code is a non-critical  GeneralizedTime

5.3.4  Certificate Issuer

   This CRL entry extension that
   provides a registered instruction identifier which indicates identifies the
   action to be taken after encountering a certificate issuer associated
   with an entry in an indirect CRL, i.e. a CRL that has been
   placed the indirectCRL
   indicator set in its issuing distribution point extension. If this
   extension is not present on hold.

   id-ce-holdInstructionCode the first entry in an indirect CRL, the
   certificate issuer defaults to the CRL issuer. On subsequent entries
   in an indirect CRL, if this extension is not present, the certificate
   issuer for the entry is the same as that for the preceding entry.
   This field is defined as follows:

   id-ce-certificateIssuer   OBJECT IDENTIFIER ::= { id-ce 23 29 }

   certificateIssuer ::=     GeneralNames

   If used by conforming CAs that issue CRLs, this extension is always
   critical.  If an implementation ignored this extension it could not
   correctly attribute CRL entries to certificates.  This specification
   recommends that implementations recognize this extension.

6  Certification Path Validation

   Certification path validation procedures for the Internet PKI are
   based on section 12.4.3 of [X.509].  Certification path processing
   verifies the binding between the subject distinguished name and/or
   subject alternative name and subject public key.  The binding is lim-
   ited by constraints which are specified in the certificates which
   comprise the path. The basic constraints and policy constraints
   extensions allow the certification path processing logic to automate
   the decision making process.

   This section describes an algorithm for validating certification



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   holdInstructionCode ::= OBJECT IDENTIFIER

   The following instruction codes have been defined.


   paths.  Conforming appli-
   cations that process implementations of this extension specification are not
   required to implement this algorithm, but shall recognize be functionally
   equivalent to the following
   instruction codes.

   holdInstruction    OBJECT IDENTIFIER ::=
                    { iso(1) member-body(2) us(840) x9-57(10040) 2 }

   id-holdinstruction-none   OBJECT IDENTIFIER ::= {holdInstruction 1}
   id-holdinstruction-callissuer
                             OBJECT IDENTIFIER ::= {holdInstruction 2}
   id-holdinstruction-reject OBJECT IDENTIFIER ::= {holdInstruction 3}

   Conforming applications which encounter external behaviour resulting from this procedure.
   Any algorithm may be used by a id-holdinstruction-
   callissuer must call particular implementation so long as
   it derives the certificate issuer or reject correct result.

   In section 6.1, the certifi-
   cate.  Conforming applications which encounter text describes basic path validation. This text
   assumes that all valid paths begin with certificates issued by a id-holdinstruction-
   reject ID shall reject sin-
   gle "most-trusted CA". The algorithm requires the transaction. id-holdinstruction-none is
   semantically equivalent to public key of the absence
   CA, the CA's name, the validity period of a holdInstructionCode.  Its
   use is strongly deprecated for the Internet PKI.

5.3.3  Invalidity Date public key, and any
   constraints upon the set of paths which may be validated using this
   key.

   The invalidity date "most-trusted CA" is a non-critical CRL entry extension that pro-
   vides the date on which matter of policy: it is known or suspected could be a root CA in
   a hierarchical PKI; the CA that issued the private key
   was compromised verifier's own
   certificate(s); or that any other CA in a network PKI.  The path valida-
   tion procedure is the certificate otherwise became invalid.
   This date may be earlier than same regardless of the revocation date in choice of "most-trusted
   CA."

   section 6.2 describes extensions to the CRL entry,
   but it must be later than basic path validation algo-
   rithm. Two specific cases are discussed: the issue date case where paths may
   begin with one of several trusted CAs; and where compatibility with
   the previously issued
   CRL.  Remember PEM architecture is required.

   6.1 Basic Path Validation

   The text assumes that the revocation date trusted public key (and related informa-
   tion) is contained in a "self-signed" certificate. This simplifies
   the CRL entry specifies description of the date path processing procedure.  Note that the CA revoked sig-
   nature on the certificate.  Whenever this informa-
   tion self-signed certificate does not provide any security
   services.  The public key it contains is available, CAs are strongly encouraged trusted because of other
   procedures used to share it with CRL
   users.

   The GeneralizedTime values included in this field shall be expressed
   in Greenwich Mean Time (Zulu), and shall be specified obtain and interpreted
   as defined in Section 4.1.2.5.2.

   id-ce-invalidityDate OBJECT IDENTIFIER ::= { id-ce 24 }

   invalidityDate ::=  GeneralizedTime

6  Certificate Path Validation

   Certification path validation procedures for the Internet PKI are
   based on Section 12.4.3 protect it.

   The goal of [X.509].  Certification path processing
   verifies validation is to verify the binding between the subject a sub-
   ject distinguished name or subject alternative name and sub-
   ject subject pub-
   lic key, as represented in the "end entity" certificate, based on the
   public key. key of the "most-trusted CA".  This requires obtaining a
   sequence of certificates that support that binding.  The binding procedures
   performed to obtain this sequence is limited by constraints which are
   specified in outside the scope of this sec-
   tion.

   The following text also assumes that certificates which comprise do not use subject
   or unique identifier fields or private critical extensions, as recom-
   mended within this profile.  However, if these components appear in
   certificates, they must be processed.  Finally, policy qualifiers are
   also neglected for the path. The basic sake of clarity.

   A certification path is a sequence of n certificates where:



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   constraints and policy constraints extensions allow


      * for all x in {1,(n-1)}, the certification
   path processing logic to automate subject of certificate x is the decision making process.
      issuer of certificate x+1.
      * certificate x=1 is the the self-signed certificate, and
      * certificate x=n is the end entity certificate.

   This section describes an algorithm for validating certification
   paths.  Conforming implementations of this specification assumes the following inputs are not
   required to implement this algorithm, but shall be functionally
   equivalent provided to the external behaviour resulting from this procedure.
   Any algorithm may be used by path
   processing logic:

      (a)  a particular implementation so long as
   it derives the correct result.

   The following text assumes that all valid paths begin with the public
   key certification path of length n;

      (b)  a single "most-trusted CA". The "most-trusted CA" is a matter set of policy: it could be a root CA in initial policy identifiers (each comprising a hierarchical PKI; the CA that
   issued the verifier's own certificate(s);
      sequence of policy element identifiers), which identifies one or
      more certificate policies, any other CA in a net-
   work PKI.  The path validation procedure is the same regardless of
   the choice one of "most-trusted CA."

   The text assumes that this public key is contained in a "self-signed"
   certificate. This simplifies which would be acceptable
      for the description purposes of the certification path processing
   procedure.  Note that processing, or the signature on special
      value "any-policy";

      (c)  the self-signed certificate
   does current date/time (if not provide any security services.  The public key it contains
   is trusted because of other procedures used available internally to obtain the
      certification path processing module); and protect it.

   The goal

      (d)  the time, T, for which the validity of the path validation is to verify the binding between a sub-
   ject distinguished name and subject public key, as represented in the
   "end entity" certificate, based on the public key of the "most-
   trusted CA".  This requires obtaining a sequence of certificates that
   support that binding.  The procedures performed to obtain this
   sequence is outside the scope of this section.

   The following text also assumes that certificates do not use subject
   or unique identifier fields or private critical extensions, as recom-
   mended within this profile.  However, if these components appear in
   certificates, they must should be processed.  Finally, policy qualifiers are
   also neglected for the sake of clarity.

   A certification path is a sequence of n certificates where:

      * for all x in {1,(n-1)}, the subject of certificate x is the
      issuer of certificate x+1.
      * certificate x=1 is the the self-signed certificate, and
      * certificate x=n is the end entity certificate.

   This section assumes the following inputs are provided to the path
   processing logic:

      (a)  a certification path of length n;




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      (b)  a set of initial policy identifiers (each comprising a
      sequence of policy element identifiers), which identifies one or
      more certificate policies, any one of which would
      determined.  (This may be acceptable
      for the purposes of certification path processing, or the special
      value "any-policy"; and

      (c) the current date/time (if not available internally to date/time, or some point in
      the
      certification path processing module). past.)

   From the inputs, the procedure intializes five state variables:

      (a)  acceptable policy set:  A set of certificate policy identif-
      iers comprising the policy or policies recognized by the public
      key user together with policies deemed equivalent through policy
      mapping. The initial value of the acceptable policy set is the
      special value "any-policy".

      (b)  constrained subtrees:  A set of root names defining a set of
      subtrees within which all subject names in subsequent certificates
      in the certification path shall fall. The initial value is
      "unbounded".

      (c)  excluded subtrees:  A set of root names defining a set of
      subtrees within which no subject name in subsequent certificates
      in the certification path may fall. The initial value is "empty".

      (d)  explicit policy: an integer which indicates if an explicit
      policy identifier is required. The integer indicates the first
      certificate in the path where this requirement is imposed. Once
      set, this variable may be decreased, but may not be increased.
      (That is, if a certificate in the path requires explicit policy
      identifiers, a later certificate can not remove this requirement.)
      The initial value is n+1.




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      (e)  policy mapping: an integer which indicates if policy mapping
      is permitted.  The integer indicates the last certificate on which
      policy mapping may be applied.  Once set, this variable may be
      decreased, but may not be increased. (That is, if a certificate in
      the path specifies policy mapping is not permitted, it can not be
      overriden by a later certificate.) The initial value is n+1.

   The actions performed by the path processing software for each certi-
   ficate i=1 through n are described below.  The self-signed certifi-
   cate is certificate i=1, the end entity certificate is i=n. The pro-
   cessing is performed sequentially, so that processing certificate i
   affects the state variables for processing certificate (i+1). Note
   that actions (h) through (l) (m) are not applied to the end entity certi-
   ficate (certificate n).



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   The path processing actions to be performed are:

      (a)  Verify the basic certificate information, including:

         (1) the certificate was signed using the subject public key
         from certificate i-1 (in the special case i=1, this step may be
         omitted; if not, use the subject public key from the same cer-
         tificate),

         (2) the certificate is not expired, and (if present) the
         private key usage validity period is satisfied, includes time T,

         (3) the certificate has had not been revoked at time T and is not
         currently on hold status that commenced before time T, (this
         may be deter-
         mined determined by obtaining current CRL, current the appropriate CRL or status
         information, or by out-of-band mechanisms), and

         (4) the subject and issuer names chain correctly.  (If correctly (that is, the
         issuer of this certificate was the subject of the previous cer-
         tificate
         tificate.)  If the certificate has an empty sequence in the
         name field, name chaining will use the critical subjectAltNames
         and issuerAltNames
         fields.) fields.

      (b)  Verify that the subject name or critical and subjectAltName extension
      (critical or noncritical) is consistent with the constrained subtrees sub-
      trees state vari-
      ables; and variables.

      (c)  Verify that the subject name or critical and subjectAltName extension
      (critical or noncritical) is consistent with the excluded subtrees
      state vari-
      ables. variables.

      (d)  Verify that policy information is consistent with the initial
      policy set:




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         (1) if the explicit policy state variable is less than or equal
         to i, a policy identifier in the certificate must be in the
         initial policy set; and

         (2) if the policy mapping variable is less than or equal to i,
         the policy identifier may not be mapped.

      (e)  Verify that policy information is consistent with the accept-
      able policy set:

         (1) if the certificate policies extension is marked critical,
         the intersection of the policies extension and the acceptable
         policy set must be non-null;

         (2) the acceptable policy set is assigned the resulting inter-
         section as its new value.

      (g) Verify that the intersection of the acceptable policy set and



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      the intial initial policy set is non-null.

      (h)  Recognize and process any other critical extension present in
      the certificate.

      (i) Verify that the certificate is a CA certificate (as specified
      in a basicConstraints extension or as verified out-of-band).

      (j)  If permittedSubtrees is present in the certificate, set the
      constrained subtrees state variable to the intersection of its
      previous value and the value indicated in the extension field.

      (k)  If excludedSubtrees is present in the certificate, set the
      excluded subtrees state variable to the union of its previous
      value and the value indicated in the extension field.

      (l)  If a policy constraints extension is included in the certifi-
      cate, modify the explicit policy and policy mapping state vari-
      ables as follows:

         (1) If requireExplicitPolicy is present and has value r, the
         explicit policy state variable is set to the minimum of (a) its
         current value and (b) the sum of r and i (the current certifi-
         cate certificate
         in the sequence).

         (2) If inhibitPolicyMapping is present and has value q, the
         policy mapping state variable is set to the minimum of (a) its
         current value and (b) the sum of q and i (the current certifi-
         cate certificate
         in the sequence).




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      (m) If a key usage extension is marked critical, ensure the key-
      CertSign bit is set.

   If any one of the above checks fail, the procedure terminates,
   returning a failure indication and an appropriate reason.  If none of
   the above checks fail on the end-entity certificate, the procedure
   terminates, returning a success indication together with the set of
   all policy qualifier values encountered in the set of certificates.

   Notes:

   6.2 Extending Path Validation

   The path validation algorithm presented in 6.1 is based on several
   simplifying assumptions (e.g., a single trusted CA that starts all
   valid paths). This algorithm may be extended for cases where the
   assumptions do not hold.

   This procedure may be extended for multiple trusted CAs by providing
   a set of self-signed certificates to the validation module.  In this
   case, a valid path could begin with any one of the self-signed certi-
   ficates.  Limitations in the trust paths for any particular key may
   be incorporated into the self-signed certificate's extensions. In
   this way, the self-signed certificates permit the path validation
   module to automatically incorporate local security policy and
   requirements.

   It is also possible to specify an extended version of the above
   certification cer-
   tification path processing procedure which results in default
   behaviour identical to the rules of Privacy Enhanced Mail PEM [RFC 1422].  In this extended
   version, additional inputs to the procedure are a list of one or more
   Policy Certification Authoritys Authorities (PCAs) names and an indicator of the
   position in the certification path where the PCA is expected.  At the
   nominated PCA position, the CA name is compared against this list.
   If a recognized PCA name is found, then a con-
   straint constraint of SubordinateToCA Subordina-
   teToCA is implicitly assumed for the remainder of the certification
   path and processing continues.  If no valid PCA name is found, and if
   the certification path cannot be validated on the basis of identified
   policies, then the certification path is



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7  Algorithm Support

   This procedure may also be extended by providing a set of self-signed
   certificates to the validation module.  In this case, a valid path
   could begin with any one of the self-signed certificates.  These
   self-signed certificates permit the path validation module to
   automatically incorporate local security policy and requirements.

7  Algorithm Support

   This section describes cryptographic algorithms which section describes cryptographic algorithms which may be used
   with this standard. profile.  The section describes one-way hash functions and
   digital signature algorithms which may be used to sign certificates
   and CRLs, and identifies object identifiers OIDs for public keys contained in a certificate. certifi-
   cate.

   Conforming CAs and applications are not required to support the algo-
   rithms or algorithm identifiers described in this section.  However,
   this profile requires



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   conforming CAs and applications to conform when
   they that use the algorithms identified here.
   here shall support them as specified.

7.1  One-way Hash Functions

   This section identifies one-way hash functions for use in the Inter-
   net PKI.  One-way hash functions are also called message digest algo-
   rithms. SHA-1 is the preferred one-way hash function for the Internet
   PKI.  However, PEM uses MD2 for certificates [RFC 1422] [RFC 1423]
   and MD5 is used in other legacy applications.  For this reason, MD2
   and MD5 are included in this profile.

7.1.1  MD2 One-way Hash Function

   MD2 was developed by Ron Rivest, but Rivest for RSA Data Security Security. RSA Data Secu-
   rity has not placed the MD2 algorithm in the public domain.  Rather,
   RSA Data Security has granted license to use MD2 for non-commercial
   Internet Privacy-
   Enhanced Privacy-Enhanced Mail.  For this reason, MD2 may continue to
   be used with PEM certificates, but SHA-1 is preferred.  MD2 produces
   a 128-bit "hash" of the input.  MD2 is fully described in RFC 1319
   [RFC 1319].

   At the Selected Areas in Cryptography '95 conference in May 1995,
   Rogier and Chauvaud presented an attack on MD2 that can nearly find
   collisions [RC95].  Collisions occur when one can find two different
   messages that generate the same message digest.  A checksum operation
   in MD2 is the only remaining obstacle to the success of the attack.
   For this reason, the use of MD2 for new applications is discouraged.
   It is still reasonable to use MD2 to verify existing signatures, as
   the ability to find collisions in MD2 does not enable an attacker to
   find new messages having a previously computed hash value.



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   << More information on the attack and its implications can be
   obtained from a RSA Laboratories security bulletin.  These bulletins
   are available from <http://www.rsa.com/>. >>

7.1.2  MD5 One-way Hash Function

   MD5 was developed by Ron Rivest in 1991.  The for RSA Data Security. RSA Data Secu-
   rity has placed the MD5 algorithm takes as
   input a message of arbitrary length and in the public domain.  MD5 produces as output
   a 128-bit
   "fingerprint" or "message digest" "hash" of the input.  The  MD5 message dig-
   est algorithm is specified by fully described in RFC 1321, "The MD5 Message-Digest
   Algorithm"[RFC1321]. 1321
   [RFC 1321].

   Den Boer and Bosselaers [DB94] have found pseudo-collisions for MD5,
   but there are no other known cryptanalytic results.  The use of MD5
   for new applications is discouraged.  It is still reasonable to use
   MD5 to verify existing signatures.

7.1.3  SHA-1 One-way Hash Function

   SHA-1 was developed by the U.S. Government.  The algorithm takes as
   input a message of arbitrary length and  SHA-1 produces as output a 160-bit
   "hash" of the input. SHA-1 is fully described in FIPS 180-1 [FIPS



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   180-1].

   SHA-1 is the one-way hash function of choice for use with both the
   RSA and DSA signature algorithms (see Section sec. 7.2).

7.2  Signature Algorithms

   Certificates and CRLs described by this standard may be signed with
   any public key signature algorithm.  The certificate or CRL indicates
   the algorithm through an algorithmidentifier algorithm identifier which appears in the
   signatureAlgorithm field in a Certificate or CertificateList.  This
   algorithmidentifier
   algorithm identifier is an OID and has optionally associated parame-
   ters.  This section identifies algorithm identifiers and parameters
   that shall be used in the signatureAlgorithm field in a Certificate
   or Certifi-
   cateList. CertificateList.

   RSA and DSA are the most popular signature algorithms used in the
   Internet.  Signature algorithms are always used in conjunction with a
   one-way hash function identified in Section section 7.1.

   The signature algorithm (and and one-way hash function) function used to sign a
   certificate cer-
   tificate or CRL is indicated by use of an algorithm identifier.  An
   algorithm identifier is an object identifier, OID, and may include associated parameters. parame-
   ters.  This section identifies OIDS for RSA and DSA.  The contents of
   the parameters component in signatureAlgorithm field of a Certificate
   or CertificateList shall always be present with a value of NULL.



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   vided for each algorithm.

   The data to be signed (e.g., the one-way hash function output value)
   is formatted for the signature algorithm to be used.  Then, a private
   key operation (e.g., RSA encryption) is performed to generate the
   signature value.  This signature value is then ASN.1 encoded as a BIT
   STRING and included in the Certificate or CertificateList (in in the
   signature field). sig-
   nature field.

7.2.1  RSA Signature Algorithm

   A patent statement regarding the RSA algorithm can be found at the
   end of this profile.

   The RSA algorithm is named for its inventors: Rivest, Shamir, and
   Adleman.  This profile includes three signature algorithms based on
   the RSA asymmetric encryption algorithm. The signature algorithms
   combine RSA with either the MD2, MD5, or the SHA-1 one-way hash func-
   tions.

   The signature algorithm with MD2 and the RSA encryption algorithm is
   defined in PKCS #1 [PKCS#1]. [RFC 2313].  As defined in PKCS #1, RFC 2313, the ASN.1 object
   identifier OID
   used to identify this signature algorithm is:



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        md2WithRSAEncryption OBJECT IDENTIFIER  ::=  {
            iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1)
            pkcs-1(1) 2  }

   The signature algorithm with MD5 and the RSA encryption algorithm is
   defined in PKCS #1 [PKCS#1]. [RFC 2313].  As defined in PKCS #1, RFC 2313, the ASN.1 object
   identifier OID
   used to identify this signature algorithm is:

        md5WithRSAEncryption OBJECT IDENTIFIER  ::=  {
            iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1)
            pkcs-1(1) 4  }

   The signature algorithm with SHA-1 and the RSA encryption algorithm
   is defined in by implemented using the OSI Interoperability Workshop in [OIW]. Padding padding and encoding conventions described
   in PKCS #1, section 8.1, must be used.  As
   defined in [OIW], #1 [RFC 2313]. The message digest is computed using the SHA-1
   hash algorithm.  The ASN.1 object identifier used to identify this
   signature algorithm is:

        sha1WithRSASignature

        sha-1WithRSAEncryption OBJECT IDENTIFIER  ::=  {
            iso(1) identified-organization(3) oiw(14)
            secsig(3) algorithm(2) 29 member-body(2) us(840) rsadsi(113549) pkcs(1)
            pkcs-1(1) 5  }

   When any of these three object identifiers OIDs appears within the ASN.1 type AlgorithmIdentifier, Algorith-
   mIdentifier, the parameters component of that type shall be the ASN.1
   type NULL.




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   The data to be signed (e.g., the one-way hash function output value)
   is first ASN.1 encoded as an OCTET STRING and the result is encrypted
   (e.g., using RSA Encryption) to form the signed quantity. When sign-
   ing, the RSA algorithm generates an integer y. This signature value
   is then ASN.1 encoded as a BIT STRING, such that the most significant
   bit in y is the first bit in the bit string and the least significant
   bit in y is the last bit in the bit string, and included in the Cer-
   tificate or CertificateList (in the signature field).

   (In general the conversion to a bit string occurs in two steps.  The
   integer y is converted to an octet string such that the first octet
   has the most significance and the last octet has the least signifi-
   cance. The octet string is converted into a bit string such that the
   most significant bit of the first octet shall become the first bit in
   the bit string, generation process and the least significant bit encoding of the last octet result
   is
   the last bit described in the BIT STRING.) detail in RFC 2313.

7.2.2  DSA Signature Algorithm

   A patent statement regarding the DSA can be found at the end of this
   profile.

   The Digital Signature Algorithm (DSA) is also called the Digital Sig-
   nature Standard (DSS).  DSA was developed by the U.S. Government, and
   DSA is used in conjunction with the the SHA-1 one-way hash function.
   DSA is fully described in FIPS 186 [FIPS 186].  The ASN.1 object
   identifiers OIDs used
   to identify this signature algorithm are:

           id-dsa-with-sha1 ID  ::=  {
                   iso(1) member-body(2) us(840) x9-57 (10040)
                   x9cm(4) 3 }

   The

   Where the id-dsa-with-sha1 algorithm syntax has NULL parameters. The DSA
   parameters in the subjectPublicKeyInfo field of identifier appears as the certificate of algo-
   rithm field in an AlgorithmIdentifier, the issuer encoding shall apply to the verification of omit the signature.

   If
   parameters field.  That is, the subjectPublicKeyInfo AlgorithmIdentifier field has NULL param-
   eters and the CA signed the subject certificate using DSA, then the
   certificate issuer's parameters apply to shall be a
   SEQUENCE of one component - the subject's OBJECT IDENTIFIER id-dsa-with-sha1.



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   The DSA key. If parameters in the subjectPublicKeyInfo AlgorithmIdentifier field has NULL parame-
   ters and of the CA signed certifi-
   cate of the subject with a signature algorithm other
   than DSA, then clients issuer shall not validate apply to the certificate. verification of the signature.

   When signing, the DSA algorithm generates two values.  These values
   are commonly referred to as r and s.  To easily transfer these two
   values as one signature, they shall be ASN.1 encoded using the fol-
   lowing ASN.1 structure:




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           Dss-Sig-Value  ::=  SEQUENCE  {
                   r       INTEGER,
                   s       INTEGER  }

7.3  Subject Public Key Algorithms

   Certificates described by this standard profile may convey a public key for
   any public key algorithm. The certificate indicates the algorithm
   through an algorithmidentifier. algorithm identifier.  This algorithm identfieier identifier is an OID
   and optionally associated parameters.

   This section identifies preferred OIDs and parameters for the RSA,
   DSA, and Diffie-Hellman algorithms.  Conforming CAs shall use the
   identified OIDs when issuing certificates containing public keys for
   these algorithms. Conforming applications supporting any of these
   algorithms shall, at a minimum, recognize the OID identified in this
   section.

7.3.1  RSA Keys

   The object identifier OID rsaEncryption identifies RSA public keys.

        pkcs-1 OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840)
                       rsadsi(113549) pkcs(1) 1 }

        rsaEncryption OBJECT IDENTIFIER ::=  { pkcs-1 1}

   The rsaEncryption object identifier OID is intended to be used in the algorithm field
   of a value of type AlgorithmIdentifier. The parame-
   ters parameters field shall
   have ASN.1 type NULL for this algorithm identifier.

   The rsa RSA public key shall be encoded using the ASN.1 type RSAPub-
   licKey:

      RSAPublicKey ::= SEQUENCE {
         modulus            INTEGER, -- n
         publicExponent     INTEGER  -- e -- }

   where modulus is the modulus n, and publicExponent is the public
   exponent e.  The DER encoded RSAPublicKey is the value of the BIT



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   STRING subjectPubliKey. subjectPublicKey.

   This object identifier OID is used in public key certificates for both RSA signature
   keys and RSA encryption keys. The intended application for the key
   may be indicated in the key usage field (see Section sec. 4.2.1.3).  The use
   of a single key for both signature and encryption purposes is not
   recommended, but is not forbidden.



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   If the keyUsage extension is present in an end entity certificate
   which conveys an RSA public key, any combination of the following
   values may be present:  digitalSignature; nonRepudiation;
      keyEncipherment; keyEnci-
   pherment; and dataEncipherment.  If the keyUsage extension is present
   in a CA certificate which con-
   veys conveys an RSA public key, any combination
   of the following values may be present:  digitalSignature;
      nonRepudiation; nonRepudi-
   ation; keyEncipherment; dataEncipherment; keyCertSign; and cRLSign.
   However, this specification recommends that if keyCertSign or cRLSign
   is present, both keyEncipherment and dataEncipherment should not be
   present.

7.3.2  Diffie-Hellman Key Exchange Key

   This diffie-hellman object identifier

   The Diffie-Hellman OID supported by this standard profile is defined by ANSI X9.42.
   X9.42 [X9.42].

        dhpublicnumber OBJECT IDENTIFIER ::= { iso(1) member-body(2)
                  us(840) ansi-x942(10046) number-type(2) 1 }

   The dhpublicnumber object identifier OID is intended to be used in the algorithm field
   of a value of type AlgorithmIdentifier. The parame-
   ters parameters field of that
   type, which has the algorithm-specific syntax ANY DEFINED BY algorithm, would algo-
   rithm, have the ASN.1 type DHParameter GroupParameters for this algorithm.

        DHParameter

        DomainParameters ::= SEQUENCE {
          prime
              p       INTEGER, -- p
          base odd prime, p=jq +1
              g       INTEGER, -- generator, g
              q       INTEGER, -- factor of p-1
              j       INTEGER OPTIONAL, -- subgroup factor
              validationParms  ValidationParms OPTIONAL }

        ValidationParms ::= SEQUENCE {
              seed             BIT STRING,
              pgenCounter      INTEGER }

   The fields of type DHParameter DomainParameters have the following meanings:

      prime is

      p identifies the prime p.

      base is p defining the base g.

   The Diffie-Hellman public key shall be ASN.1 encoded as an INTEGER; Galois field;

      g specifies the generator of the mutiplicative subgroup of order



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   this encoding shall be used as the contents (i.e.,


      g;

      q specifies the value) prime factor of p-1;

      j optionally specifies the
   subjectPublicKey component (a BIT STRING) of value that satisfies the equation
      p=jq+1 to support the optional verification of group parameters;

      seed optionally specifies the bit string parameter used as the
      seed for the system parameter generation process; and

      pgenCounter optionally specifies the integer value output as part
      of the of the system parameter prime generation process.

   If either of the parameter generation components (pgencounter or
   seed) is provided, the other must be present as well.

   The Diffie-Hellman public key shall be ASN.1 encoded as an INTEGER;
   this encoding shall be used as the contents (i.e., the value) of the
   subjectPublicKey component (a BIT STRING) of the subjectPublicKeyInfo
   data element.

      DHPublicKey ::= INTEGER -- public key key, y = g^x mod p

   If the keyUsage extension is present in a certificate which conveys a
   DH public key, the following values may be present:  keyAgreement;
   encipherOnly; and decipherOnly.  At most one of encipherOnly and
   decipherOnly shall be asserted in keyUsage extension.

7.3.3  DSA Signature Keys

   The object identifier Digital Signature Algorithm (DSA) is also known as the Digitial
   Signature Standard (DSS). The DSA OID supported by this standard profile is

        id-dsa ID ::= { iso(1) member-body(2) us(840) x9-57(10040)
                  x9cm(4) 1 }

   The id-dsa algorithm syntax includes optional parameters.  These
   parameters are commonly referred to as p, q, and g.  When omitted,
   the parameters component shall be omitted entirely. That is, the
   AlgorithmIdentifier shall be a SEQUENCE of one component - the OBJECT
   IDENTIFIER id-dsa.

   If the DSA algorithm parameters are present and have in the value NULL. subjectPublicKey-
   Info AlgorithmIdentifier, the parameters are included using the fol-
   lowing ASN.1 structure:

        Dss-Parms  ::=  SEQUENCE  {
            p             INTEGER,



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            q             INTEGER,
            g             INTEGER  }


   If the DSA algorithm parameters are absent from the subjectPublicKey-
   Info AlgorithmIdentifier and the CA signed the subject certificate
   using DSA, then the certificate issuer's DSA parameters apply to the
   subject's DSA key.  If the DSA algorithm parameters are absent from
   the subjectPublicKeyInfo AlgorithmIdentifier and the CA signed the
   subject certificate using a signature algorithm other than DSA, then
   the subject's DSA parameters are distributed by other means.  The
   parameters are included using the following ASN.1 structure:

        Dss-Parms  ::=  SEQUENCE  {
            p             INTEGER,
            q             INTEGER,
            g             INTEGER  }  If the
   subjectPublicKeyInfo AlgorithmIdentifier field has NULL param-
   eters and the CA signed the subject certificate using DSA, then omits the
   certificate issuer's parameters apply to the subject's DSA key. If
   the subjectPublicKeyInfo AlgorithmIdentifier field has NULL parame-
   ters
   component and the CA signed the subject with a signature algorithm
   other than DSA, then clients shall not validate reject the certificate.




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   When signing, DSA algorithm generates two values.  These values are
   commonly referred to as r and s.  To easily transfer these two values
   as one signature, they are ASN.1 encoded using the following ASN.1
   structure:

        Dss-Sig-Value  ::=  SEQUENCE  {
            r             INTEGER,
            s             INTEGER  }

   The encoded signature is conveyed as the value of the BIT STRING sig-
   nature in a Certificate or CertificateList.

   The DSA public key shall be ASN.1 DER encoded as an INTEGER; this encod-
   ing
   encoding shall be used as the contents (i.e., the value) of the sub-
   jectPublicKey component (a BIT STRING) of the SubjectPublicKeyInfo
   data element.

        DSAPublicKey ::= INTEGER -- public key key, Y


   If the keyUsage extension is present in an end entity certificate
   which conveys a DSA public key, any combination of the following
   values may be present:  digitalSignature; and nonRepudiation.

   If the keyUsage extension is present in an CA certificate which con-
   veys a DSA public key, any combination of the following values may be
   present:  digitalSignature; nonRepudiation; keyCertSign; and cRLSign.

8 References

   [FIPS 180-1]  Federal Information Processing Standards Publication
            (FIPS PUB) 180-1, Secure Hash Standard, 17 April 1995.
            [Supersedes FIPS PUB 180 dated 11 May 1993.]



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   [FIPS 186] Federal Information Processing Standards Publication
            (FIPS PUB) 186, Digital Signature Standard, 18 May 1994.

   [OIW]    Stable Implementation Agreements for Open Systems
            Interconnection Protocols: Part 12 - OS Security,
            Output  from the June 1995 Open Systems Environment



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            Implementors' Workshop (OIW).

   [PKCS#1]

   [PKCS #9] PKCS #1: RSA Encryption Standard, #9: Selected Attribute Types, Version 1.4, 1.1, RSA Data
            Security, Inc., 3 June 1991. November 1, 1993.

   [RC95]   Rogier, N. and Chauvaud, P., "The compression function of
            MD2 is not collision free," Presented at Selected Areas in
            Cryptography '95, Carleton University, Ottawa, Canada,
            18-19 May 1995.

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

   [RFC 822] D. Crocker, "Standard for the format of ARPA Internet text
            messages", August 1982.

   [RFC 1034] P.V. Mockapetris, "Domain names - concepts and facili-
   ties",
            November 1987.

   [RFC 1319] Kaliski, B., "The MD2 Message-Digest Algorithm," RFC 1319,
            RSA Laboratories, April 1992.

   [RFC 1422] Kent, S.,  "Privacy Enhancement for Internet Electronic
            Mail: Part II: Certificate-Based Key Management," RFC
            1422, BBN Communications, February 1993.

   [RFC 1423] Balenson, D., "Privacy Enhancement for Internet Electronic
            Mail: Part III: Algorithms, Modes, and Identifiers,"
            RFC 1423, Trusted Information Systems, February 1993.

   [RFC 1738] T. Berners-Lee, L. Masinter & M. McCahill, "Uniform
              Resource Locators (URL)," December 1994.

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

   [RFC 1778] 1519] V. Fuller, T. Howes, S. Kille, W. Yeong, C. Robbins, "The String
            Representation of Standard Attribute Syntaxes", March 1995. Li, J. Yu, and K. Varadhan. "Classless
            Inter-Domain Routing (CIDR): an Address Assignment and
            Aggregation Strategy", September 1993.

   [RFC 1883] S. Deering, Deering and R.  Hinden, Hinden. "Internet Protocol, Version 6
            (IPv6),"
            (IPv6) Specification", December 1995.

   [RFC 1959] T. Howes, M. Smith, "An LDAP URL Format", RFC 1959,
            June 1996.

   [RFC 2044] F. Yergeau, "UTF-8, a transformation format of Unicode
            and ISO 10646", October 1996.

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

   [RFC 2277] H. Alvestrand, "IETF Policy on Character Sets and
            Languages", January 1998.

   [RFC 2279] F. Yergeau, "UTF-8, a transformation format of ISO 10646",
            January 1998.

   [PKIXMGMT] C. Adams, S. Farrell, "Internet Public Key Infrastructure



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            Certificate Management Protocols",
            draft-ietf-pkix-ipki3cmp-07.txt, February 1998.

   [PKIXLDAP] S. Boyeun, T. Howes and P. Richard "Internet Public Key
            Infrastructure Operational Protocols - LDAP",
            draft-ietf-pkix-ipki2opp-07.txt,


   [RFC 2313] B. Kaliski, "PKCS #1: RSA Encryption Version 1.5",
            March 1998.

   [PKIXOCSP] M. Myers, in "Internet Public Key Infrastructure Part 2:
            Operational Protocols", draft-ietf-pkix-ocsp-02.txt,
            February 1998.

   [PKIXFTP] R. Housley, "Internet Public Key Infrastructure Operational
            Protocols:  FTP and HTTP",
            draft-ietf-pkix-opp-ftp-http-02.txt, November 1997.

   [SDN.701R]

   [SDN.701] SDN.701, "Message Security Protocol", Protocol 4.0", Revision 4.0
            1996-06-07 with "Corrections to Message Security Protocol,
            SDN.701, Rev 4.0, 96-06-07." August 30, 1996. A
            1997-02-06.

   [X.208]  CCITT Recommendation X.208: Specification of Abstract
              Syntax Notation One (ASN.1), 1988.

   [X.509]  ITU-T Recommendation X.509 (1197 (1997 E): Information
            Technology - Open Systems Interconnection - The
            Directory: Authentication Framework, June 1997.

   [X9.42]  ANSI X9.42-199x, Public Key Cryptography for The Financial
            Services Industry: Agreement of Symmetric Algorithm Keys
            Using Diffie-Hellman (Working Draft), December 1997.

   [X9.55]  ANSI X9.55-1995, Public Key Cryptography For The Financial
            Services Industry: Extensions To Public Key Certificates
            And Certificate Revocation Lists, 8 December, 1995.

   [X9.57]  ANSI X9.57-199x, Public Key Cryptography For The Financial
            Services Industry: Certificate Management (Working Draft),
            21 June, 1996.

9  Patent Statements

   The Internet PKI relies on the use of patented public key technology
   and secure hash technology for digital signature services.  This
   specification references public key encryption technology for provi-
   sioning key exchange services.  This specification also permits the
   use of the cRLDistributionPoints extension to assist in the manage-
   ment of certificate revocation lists.

   The Internet Standards Process as defined in RFC 1310 requires a
   written statement from the Patent holder that a license will be made
   available to applicants under reasonable terms and conditions prior
   to approving a specification as a Proposed, Draft or Internet Stan-
   dard.



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   Patent statements for DSA, RSA, Diffie-Hellman Diffie-Hellman, and one method for
   managing CRLs Hellman-Merkle
   follow.  These statements have been supplied by the patent holders,
   not the authors of this profile.

   The Internet Society, Internet Architecture Board, Internet Engineer-
   ing Steering Group and the Corporation for National Research Initia-
   tives take no position on the validity or scope of the following
   patents and patent applications, nor on the appropriateness of the
   terms of the assurance. The Internet Society and other groups men-
   tioned above have not made any determination as to any other intel-
   lectual



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   intellectual property rights which may apply to the practice of this stan-
   dard.
   standard.  Any further consideration of these matters is the user's own
   responsibility.

9.1  Digital Signature Algorithm (DSA)

   The U.S. Government holds patent 5,231,668 on the Digital Signa-
      ture Signature
   Algorithm (DSA), which has been incorporated into Federal Information
   Processing Standard (FIPS) 186.  The patent was issued on July 27,
   1993.

   The National Institute of Standards and Technology (NIST) has a long
   tradition of supplying U.S. Government-developed techniques to committees com-
   mittees and working groups for inclusion into standards on a
   royalty-free basis.  NIST has made the DSA patent available
      royalty-free royalty-
   free to users worldwide.

   NIST has provided the following statement with regard to this patent:

      Regarding patent infringement, FIPS 186 summarizes our position;
      the Department of Commerce is not aware of any patents that would
      be infringed by the DSA.  Questions regarding this matter may be
      directed to the Deputy Chief Counsel for NIST.

9.2  RSA Signature and Encryption

   The Massachusetts Institute of Technology has granted RSA Data
      Security, Secu-
   rity, Inc., exclusive sub-licensing rights to the following patent
   issued in the United States:

   Cryptographic Communications System and Method ("RSA"), No. 4,405,829

   RSA Data Security, Inc. has provided the following statement with
   regard to this patent:

      It is our understanding that the proposed PKIX Certificate Pro-
         file Profile
      (PKIX-1) standard currently under review contemplates the use of
      U.S Patent 4,405,829 entitled "Cryptographic Communica-
         tion Communication System
      and Method" (the "RSA patent") which patent is



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      It is RSA's business practice to make licenses to its patents
      available on reasonable and nondiscriminatory terms. Accord-
         ingly, Accordingly,
      if the foregoing identified IETF standard is adopted, RSA is willing, wil-
      ling, upon request, to grant non-exclusive licenses to such patent
      on reasonable and non-discriminatory terms and conditions to those
      who respect RSA's intellectual property rights and subject to
      RSA's then current royalty rate for the patent licensed. The royalty roy-
      alty rate for the RSA patent is presently set at 2% of the licensee's



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      licensee's selling price for each product covered by the patent.
      Any requests for license infor-
         mation information may be directed to:

         Director of Licensing
         RSA Data Security, Inc.
         100 Marine Parkway, Suite 500
         Redwood City, CA 94065

      A license under RSA's patent(s) does not include any rights to
      know-how or other technical information or license under other
      intellectual property rights.  Such license does not extend to any
      activities which constitute infringement or inducement thereto. A
      licensee must make his own determination as to whether a license
      is necessary under patents of others.

9.3  Diffie-Hellman Key Agreement and Hellman-Merkle Public Key Cryptogra-
   phy

   Patent No. 4,200,770: Cryptographic Apparatus and Method ("Diffie-
   Hellman") expired on August 19, 1997.

9.4  Hellman-Merkle Public Key Cryptography

   Patent No. 4,218,582: Public Key Cryptographic Apparatus and Method
   ("Hellman-Merkle") expired on April 29, 1997.

   Method for Efficient Management of Certificate Revocation Lists

9.5  CRL Distribution Points and Related Mechanisms

   Entrust Technologies Limited Incorporated has provided the following state-
   ment with regard to this patent:

      Entrust Technologies Incorporated advises the IETF that it holds
      the Patent (as defined herein) which may relate to the IETF. In accor-
      dance
      accordance with the Intellectual Property rights procedures of the
      IETF standards process, Entrust Technologies Limited, Incorporated, for
      itself and its subsidiaries (hereinafter called Entrust) "Entrust") will
      offer licenses under its Patent on a perpetual, royalty-free,
      non-exclusive basis and on non-
      discriminatory, non-discriminatory, fair and reasonable equitable
      terms to all parties solely for their use in complying with the
      Standard, but on condition that any such party offers to Entrust
      and its corporate affiliates similar licenses under such partys party's
      patents, if any, for use in complying with the Standard and related IETF standards. Standard.

      Any application for a license under Entrusts Entrust's Patent pursuant to
      this Patent Disclosure Statement should be made to:



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         Stephen Samson
         Entrust Technologies Limited
         8th Floor,
         750 Heron Road, Ottawa, Ontario, Canada, K1V 1A7



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         voice: (613) 247 3725

      As used herein:

      "Patent" means US Patent 5,699,431 issued on 16 December, 1997 for
      an invention known as a "Method for Efficient Management of Certi-
      ficate Revocation Lists and Update Information", which invention
      is owned or controlled by Entrust and the use of which may be
      required in conjunction with the Standard.

      "Standard" means a specification progressing through the Standard
      Track of the IETF and relating to the Public Key Infrastructure
      (X.509) specifications.

      GRANT OF RIGHTS FOR US PATENT 5,699,431

      Purpose

      This grant is made to help facilitate inclusion specification for certificate update and revocation.

10  Security Considerations

   The majority of certain
      patented technology covered under US Patent 5,699,431 (herein
      called the Technology) in the Public Key Infrastructure (X.509)
      Standard (herein called the Standard). Entrust Technologies Lim-
      ited (herein called Entrust) offers the Technology this specification is devoted to the IETF as
      a method for efficient management format and con-
   tent of Certificate Revocation Lists certificates and Update Information. It should be noted that the confirmatory
      license mentioned CRLs.  Since certificates and CRLs are digi-
   tally signed, no additional integrity service is optional, since necessary. Neither
   certificates nor CRLs need be kept secret, and unrestricted and
   anonymous access to certificates and CRLs has no security implica-
   tions.

   However, security factors outside the grant of rights is
      automatic.

      Grant scope of Rights this specification
   will affect the assurance provided to Entrust Technologies US Patent 5,699,431

      Entrust hereby covenants certificate users.  This sec-
   tion highlights critical issues that it will not assert any claims in US
      Patent 5,699,431 any continuations, divisions, or continuations-
      in-part of either, or any non-US counterparts should be considered by imple-
   mentors, administrators, and users.

   The procedures performed by CAs and RAs to validate the binding of any
   the subject's identity of their public key greatly affect the fore-
      going against any party
   assurance that makes, uses, or offers a non-
      commercial implementation of an IETF specification that includes should be placed in the Technology, or any continuation, division or continuation-in-
      part of that contribution, provided that contribution is employed certificate.  Relying parties
   may wish to implement review the Public Key Infrastructure (X.509) Standard.

      Such grant CA's certificate practice statement.  This may
   be particularly important when issuing certificates to other CAs.

   The use of rights is limited in that it does not include rights a single key pair for commercialization both signature and other purposes is
   strongly discouraged. Use of the Technology, including incorporating
      such Technology into commercial products. A license separate key pairs for commercial
      uses of signature and key
   management provides several benefits to the Technology must users. The ramifications
   associated with loss or disclosure of a signature key are different
   from loss or disclosure of a key management key. Using separate key
   pairs permits a balanced and flexible response.  Similarly, different
   validity periods or key lengths for each key pair may be applied appropriate
   in some application environments. Unfortunately, some legacy applica-
   tions (e.g., SSL) use a single key pair for at the address written
      below.

      This grant signature and key manage-
   ment.

   The protection afforded private keys is a critical factor in main-
   taining security.  On a small scale, failure of rights users to protect
   their private keys will permanently terminate with respect permit an attacker to masquerade as them, or



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      any party (and to any affiliate of the party) that asserts


   decrypt their personal information. On a
      patent it owns or controls, either directly or indirectly, against
      Entrust or any of its affiliates for implementation of, or opera-
      tion larger scale, compromise of any system utilizing
   a CA's private signing key may have a catastrophic effect.  If an
   attacker obtains the Technology. The termination private key unnoticed, the attacker may issue
   bogus certificates and CRLs.  Existence of
      rights bogus certificates and
   CRLs will occur as of undermine confidence in the date system. If the patent compromise is asserted against
      Entrust.

      Confirmatory License

      A written confirmation of this grant, and/or a license under any
      other patent under Entrust's then-current terms, conditions,
   detected, all certificates issued to the CA must be revoked, prevent-
   ing services between its users and
      royalty rates, can users of other CAs. Rebuilding
   after such a compromise will be obtained by sending problematic, so CAs are advised to
   implement a request to:

      Stephen Samson
      Entrust Technologies Limited
      8th Floor, 750 Heron Road, Ottawa, Ontario, Canada, K1V 1A7

Appendix A. Psuedo-ASN.1 Structures combination of strong technical measures (e.g., tamper-
   resistant cryptographic modules) and OIDs

   This section describes data objects used by conforming PKI components
   in appropriate management pro-
   cedures (e.g., separation of duties) to avoid such an "ASN.1-like" syntax.  This syntax is incident.

   Loss of a hybrid CA's private signing key may also be problematic.  The CA
   would not be able to produce CRLs or perform normal key rollover.
   CAs are advised to maintain secure backup for signing keys.  The
   security of the 1988 and
   1993 ASN.1 syntaxes.  The 1988 ASN.1 syntax key backup procedures is augmented with 1993
   UNIVERSAL Types UniversalString, BMPString and UTF8String. a critical factor in avoid-
   ing key compromise.

   The ASN.1 syntax does not permit availability and freshness of revocation information will affect
   the inclusion degree of type statements assurance that should be placed in a certificate.
   While certificates expire naturally, events may occur during its
   natural lifetime which negate the ASN.1 module, binding between the subject and
   public key.  If revocation information is untimely or unavailable,
   the 1993 ASN.1 standard does not permit use assurance associated with the binding is clearly reduced.  Simi-
   larly, implementations of the new UNIVERSAL types Path Validation mechanism described in modules using
   section 6 that omit revocation checking provide less assurance than
   those that support it.

   The path validation algorithm depends on the 1988 syntax.  As a
   result, this module does not conform to either version certain knowledge of the ASN.1
   standard.

   This appendix may
   public keys (and other information) about one or more trusted CAs.
   The decision to trust a CA is an important decision as it ultimately
   determines the trust afforded a certificate. The authenticated dis-
   tribution of trusted CA public keys (usually in the form of a "self-
   signed" certificate) is a security critical out of band process that
   is beyond the scope of this specification.

   In addition, where a key compromise or CA failure occurs for a
   trusted CA, the user will need to modify the information provided to
   the path validation routine.  Selection of too many trusted CAs will
   make the trusted CA information difficult to maintain.  On the other
   hand, selection of only one trusted CA may limit users to a closed
   community of users until a global PKI emerges.

   The quality of implementations that process certificates may also
   affect the degree of assurance provided.  The path validation algo-
   rithm described in section 6 relies upon the integrity of the trusted
   CA information, and especially the integrity of the public keys asso-
   ciated with the trusted CAs.  By substituting public keys for which



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   an attacker has the private key, an attacker could trick the user
   into accepting false certificates.

   Finally, the binding between a key and certificate subject cannot be
   stronger than the cryptographic module implementation and algorithms
   used to generate the signature.  Short key lengths or weak hash algo-
   rithms will limit the utility of a certificate.  CAs are encouraged
   to note advances in cryptology so they can employ strong crypto-
   graphic techniques.  In addition, CAs should decline to issue certi-
   ficates to CAs or end entities that generate weak signatures.









































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Appendix A. Psuedo-ASN.1 Structures and OIDs

   This section describes data objects used by conforming PKI components
   in an "ASN.1-like" syntax.  This syntax is a hybrid of the 1988 and
   1993 ASN.1 syntaxes.  The 1988 ASN.1 syntax is augmented with 1993
   UNIVERSAL Types UniversalString, BMPString and UTF8String.

   The ASN.1 syntax does not permit the inclusion of type statements in
   the ASN.1 module, and the 1993 ASN.1 standard does not permit use of
   the new UNIVERSAL types in modules using the 1988 syntax.  As a
   result, this module does not conform to either version of the ASN.1
   standard.

   This appendix may be converted into 1988 ASN.1 by replacing the
   defintions for the UNIVERSAL Types with the 1988 catch-all "ANY".

A.1 Explicitly Tagged Module

PKIX1Explicit88 {iso(1) identified-organization(3) dod(6) internet(1)
  security(5) mechanisms(5) pkix(7) id-mod(0) id-pkix1-explicit-88(1)}


DEFINITIONS EXPLICIT TAGS ::=

BEGIN

-- EXPORTS ALL --

-- IMPORTS NONE --

-- UNIVERSAL Types defined in '93 and '98 ASN.1
-- but required by this specification

UniversalString ::= [UNIVERSAL 28] IMPLICIT OCTET STRING
        -- UniversalString is defined in ASN.1:1993

BMPString ::= [UNIVERSAL 30] IMPLICIT OCTET STRING
      -- BMPString is the subtype of UniversalString and models
        -- the Basic Multilingual Plane of ISO/IEC/ITU 10646-1

UTF8String ::= [UNIVERSAL 12] IMPLICIT OCTET STRING
        -- The content of this type conforms to RFC 2044.

--
-- PKIX specific OIDs

id-pkix  OBJECT IDENTIFIER  ::=
         { iso(1) identified-organization(3) dod(6) internet(1)



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                    security(5) mechanisms(5) pkix(7) }
-- PKIX arcs

id-pe OBJECT IDENTIFIER  ::=  { id-pkix 1 }
        -- arc for private certificate extensions
id-qt OBJECT IDENTIFIER ::= { id-pkix 2 }
        -- arc for policy qualifier types
id-kp OBJECT IDENTIFIER ::= { id-pkix 3 }
        -- arc for extended key purpose OIDS
id-ad OBJECT IDENTIFIER ::= { id-pkix 48 }
        -- arc for access descriptors

-- policyQualifierIds for Internet policy qualifiers

id-qt-cps      OBJECT IDENTIFIER ::=  { id-qt 1 }
        -- OID for CPS qualifier
id-qt-unotice  OBJECT IDENTIFIER ::=  { id-qt 2 }
        -- OID for user notice qualifier

-- attribute data types --

Attribute       ::=     SEQUENCE {
        type            AttributeType,
        values  SET OF AttributeValue
                -- at least one value is required -- }

AttributeType           ::=   OBJECT IDENTIFIER

AttributeValue          ::=   ANY

AttributeTypeAndValue           ::=     SEQUENCE {
        type    AttributeType,
        value   AttributeValue }

-- suggested naming attributes: Definition of the following
--  information object set may be augmented to meet local
--  requirements.  Note that deleting members of the set may
--  prevent interoperability with conforming implementations.
--  presented in pairs: the AttributeType followed by the
--  type definition for the corresponding AttributeValue

--Arc for standard naming attributes
id-at           OBJECT IDENTIFIER ::= {joint-iso-ccitt(2) ds(5) 4}

-- Attributes of type NameDirectoryString
id-at-name              AttributeType   ::=     {id-at 41}
id-at-surname           AttributeType   ::=     {id-at 4}
id-at-givenName         AttributeType   ::=     {id-at 42}



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id-at-initials          AttributeType   ::=     {id-at 43}
id-at-generationQualifier       AttributeType   ::=     {id-at 44}

X520name        ::= CHOICE {
      teletexString         TeletexString (SIZE (1..ub-name)),
      printableString       PrintableString (SIZE (1..ub-name)),
      universalString       UniversalString (SIZE (1..ub-name)),
      utf8String            UTF8String (SIZE (1..ub-name)),
      bmpString             BMPString (SIZE(1..ub-name))   }

--

id-at-commonName        AttributeType   ::=     {id-at 3}

X520CommonName  ::=      CHOICE {
      teletexString         TeletexString (SIZE (1..ub-common-name)),
      printableString       PrintableString (SIZE (1..ub-common-name)),
      universalString       UniversalString (SIZE (1..ub-common-name)),
      utf8String            UTF8String (SIZE (1..ub-common-name)),
      bmpString             BMPString (SIZE(1..ub-common-name))   }

--

id-at-localityName      AttributeType   ::=     {id-at 7}

X520LocalityName ::= CHOICE {
      teletexString       TeletexString (SIZE (1..ub-locality-name)),
      printableString     PrintableString (SIZE (1..ub-locality-name)),
      universalString     UniversalString (SIZE (1..ub-locality-name)),
      utf8String          UTF8String (SIZE (1..ub-locality-name)),
      bmpString           BMPString (SIZE(1..ub-locality-name))   }

--

id-at-stateOrProvinceName       AttributeType   ::=     {id-at 8}

X520StateOrProvinceName         ::= CHOICE {
      teletexString       TeletexString (SIZE (1..ub-state-name)),
      printableString     PrintableString (SIZE (1..ub-state-name)),
      universalString     UniversalString (SIZE (1..ub-state-name)),
      utf8String          UTF8String (SIZE (1..ub-state-name)),
      bmpString             BMPString (SIZE(1..ub-state-name))   }

--

id-at-organizationName          AttributeType   ::=     {id-at 10}

X520OrganizationName ::= CHOICE {



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  teletexString    TeletexString (SIZE (1..ub-organization-name)),
  printableString  PrintableString (SIZE (1..ub-organization-name)),
  universalString  UniversalString (SIZE (1..ub-organization-name)),
  utf8String       UTF8String (SIZE (1..ub-organization-name)),
  bmpString        BMPString (SIZE(1..ub-organization-name))   }

--

id-at-organizationalUnitName    AttributeType   ::=     {id-at 11}

X520OrganizationalUnitName ::= CHOICE {
 teletexString   TeletexString (SIZE (1..ub-organizational-unit-name)),
 printableString PrintableString
                      (SIZE (1..ub-organizational-unit-name)),
 universalString UniversalString
                      (SIZE (1..ub-organizational-unit-name)),
 utf8String      UTF8String (SIZE (1..ub-organizational-unit-name)),
 bmpString       BMPString (SIZE(1..ub-organizational-unit-name))   }

--

id-at-title     AttributeType   ::=     {id-at 12}

X520Title ::=   CHOICE {
      teletexString         TeletexString (SIZE (1..ub-title)),
      printableString       PrintableString (SIZE (1..ub-title)),
      universalString       UniversalString (SIZE (1..ub-title)),
      utf8String            UTF8String (SIZE (1..ub-title)),
      bmpString             BMPString (SIZE(1..ub-title))   }

--

id-at-dnQualifier       AttributeType   ::=     {id-at 46}
X520dnQualifier ::=     PrintableString

id-at-countryName       AttributeType   ::=     {id-at 6}
X520countryName ::=     PrintableString (SIZE (2)) -- IS 3166 codes


 -- Legacy attributes

pkcs-9 OBJECT IDENTIFIER ::=
       { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 9 }

emailAddress AttributeType      ::= { pkcs-9 1 }

Pkcs9email ::= IA5String (SIZE (1..ub-emailaddress-length))




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-- naming data types --

Name            ::=   CHOICE { -- only one possibility for now --
                                 rdnSequence  RDNSequence }

RDNSequence     ::=   SEQUENCE OF RelativeDistinguishedName

DistinguishedName       ::=   RDNSequence

RelativeDistinguishedName  ::=
                    SET SIZE (1 .. MAX) OF AttributeTypeAndValue

-- Directory string type --

DirectoryString ::= CHOICE {
      teletexString             TeletexString (SIZE (1..MAX)),
      printableString           PrintableString (SIZE (1..MAX)),
      universalString           UniversalString (SIZE (1..MAX)),
      utf8String              UTF8String (SIZE (1..MAX)),
      bmpString               BMPString (SIZE(1..MAX))   }

-- certificate and CRL specific structures begin here

Certificate  ::=  SEQUENCE  {
     tbsCertificate       TBSCertificate,
     signatureAlgorithm   AlgorithmIdentifier,
     signature            BIT STRING  }

TBSCertificate  ::=  SEQUENCE  {
     version         [0]  Version DEFAULT v1,
     serialNumber         CertificateSerialNumber,
     signature            AlgorithmIdentifier,
     issuer               Name,
     validity             Validity,
     subject              Name,
     subjectPublicKeyInfo SubjectPublicKeyInfo,
     issuerUniqueID  [1]  IMPLICIT UniqueIdentifier OPTIONAL,
                          -- If present, version must be v2 or v3
     subjectUniqueID [2]  IMPLICIT UniqueIdentifier OPTIONAL,
                          -- If present, version must be v2 or v3
     extensions      [3]  Extensions OPTIONAL
                          -- If present, version must be v3 --  }

Version  ::=  INTEGER  {  v1(0), v2(1), v3(2)  }

CertificateSerialNumber  ::=  INTEGER

Validity ::= SEQUENCE {



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     notBefore      Time,
     notAfter       Time }

Time ::= CHOICE {
     utcTime        UTCTime,
     generalTime    GeneralizedTime }

UniqueIdentifier  ::=  BIT STRING

SubjectPublicKeyInfo  ::=  SEQUENCE  {
     algorithm            AlgorithmIdentifier,
     subjectPublicKey     BIT STRING  }

Extensions  ::=  SEQUENCE SIZE (1..MAX) OF Extension

Extension  ::=  SEQUENCE  {
     extnID      OBJECT IDENTIFIER,
     critical    BOOLEAN DEFAULT FALSE,
     extnValue   OCTET STRING  }

-- CRL structures

CertificateList  ::=  SEQUENCE  {
     tbsCertList          TBSCertList,
     signatureAlgorithm   AlgorithmIdentifier,
     signature            BIT STRING  }

TBSCertList  ::=  SEQUENCE  {
     version                 Version OPTIONAL,
                                  -- if present, must be v2
     signature               AlgorithmIdentifier,
     issuer                  Name,
     thisUpdate              Time,
     nextUpdate              Time OPTIONAL,
     revokedCertificates     SEQUENCE OF SEQUENCE  {
          userCertificate         CertificateSerialNumber,
          revocationDate          Time,
          crlEntryExtensions      Extensions OPTIONAL
                                         -- if present, must be converted into 1988 ASN.1 by replacing the
   defintions for the UNIVERSAL Types with the 1988 catch-all "ANY".

PKIX1 DEFINITIONS IMPLICIT TAGS::=

BEGIN v2
                               }  OPTIONAL,
     crlExtensions           [0] Extensions OPTIONAL
                                         -- UNIVERSAL Types defined in '93 ASN.1 if present, must be v2 -- but required by this specification

UniversalString ::= [UNIVERSAL 28] IMPLICIT OCTET STRING }

-- Version, Time, CertificateSerialNumber, and Extensions were
-- UniversalString is defined earlier for use in ASN.1:1993

BMPString ::= [UNIVERSAL 30] IMPLICIT OCTET STRING
        -- BMPString is the subtype of
        -- UniversalString and models the Basic Multilingual Plane
        -- of ISO/IEC 10646-1 certificate structure

AlgorithmIdentifier  ::=  SEQUENCE  {
     algorithm               OBJECT IDENTIFIER,



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     parameters              ANY DEFINED BY algorithm OPTIONAL  }
                                -- UNIVERSAL Type defined in draft '98 ASN.1
-- but required by this specification

UTF8String ::= [UNIVERSAL 12] IMPLICIT OCTET STRING
        -- The content contains a value of this the type conforms to RFC 2044.
                                -- registered for use with the
                                -- algorithm object identifier value

-- PKIX Algorithm OIDs

id-pkix and parameter structures

pkcs-1 OBJECT IDENTIFIER ::= {
     iso(1) identified-organization(3) dod(6) internet(1)
                    security(5) mechanisms(5) pkix(7) member-body(2) us(840) rsadsi(113549) pkcs(1) 1 }

rsaEncryption OBJECT IDENTIFIER ::=  { pkcs-1 1 }

md2WithRSAEncryption OBJECT IDENTIFIER  ::=  { pkcs-1 2 }

md5WithRSAEncryption OBJECT IDENTIFIER  ::=  { pkcs-1 4 }

sha1WithRSAEncryption OBJECT IDENTIFIER  ::=  { pkcs-1 5 }

id-dsa-with-sha1 OBJECT IDENTIFIER ::=  {
     iso(1) member-body(2) us(840) x9-57 (10040) x9algorithm(4) 3 }

Dss-Sig-Value  ::=  SEQUENCE  {
     r       INTEGER,
     s       INTEGER  }

dhpublicnumber OBJECT IDENTIFIER ::= {
     iso(1) member-body(2) us(840) ansi-x942(10046) number-type(2) 1 }

DomainParameters ::= SEQUENCE {
     p       INTEGER, -- PKIX arcs odd prime, p=jq +1
     g       INTEGER, -- generator, g
     q       INTEGER, -- factor of p-1
     j       INTEGER OPTIONAL, -- arc for private certificate extensions
id-pe OBJECT IDENTIFIER subgroup factor, j>= 2
     validationParms  ValidationParms OPTIONAL }

ValidationParms ::= SEQUENCE { id-pkix 1
     seed             BIT STRING,
     pgenCounter      INTEGER }
 -- arc for policy qualifier types
id-qt

id-dsa OBJECT IDENTIFIER ::= { id-pkix 2
     iso(1) member-body(2) us(840) x9-57(10040) x9algorithm(4) 1 }
-- arc for extended key purpose OIDS
id-kp OBJECT IDENTIFIER

Dss-Parms  ::=  SEQUENCE  { id-pkix 3
     p             INTEGER,
     q             INTEGER,
     g             INTEGER  }

-- arc for access descriptors
id-ad OBJECT IDENTIFIER x400 address syntax starts here



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--      OR Names

ORAddress ::= SEQUENCE { id-pkix 48
   built-in-standard-attributes BuiltInStandardAttributes,
   built-in-domain-defined-attributes
                        BuiltInDomainDefinedAttributes OPTIONAL,
   -- see also teletex-domain-defined-attributes
   extension-attributes ExtensionAttributes OPTIONAL }
-- pkix private extensions
id-pe-authorityInfoAccess OBJECT IDENTIFIER      The OR-address is semantically absent from the OR-name if the
--      built-in-standard-attribute sequence is empty and the
--      built-in-domain-defined-attributes and extension-attributes are
--      both omitted.

--      Built-in Standard Attributes

BuiltInStandardAttributes ::= SEQUENCE { id-pe 1 }
   country-name CountryName OPTIONAL,
   administration-domain-name AdministrationDomainName OPTIONAL,
   network-address      [0] NetworkAddress OPTIONAL,
   -- policyQualifierIds for Internet policy qualifiers
id-qt-cps      OBJECT IDENTIFIER see also extended-network-address
   terminal-identifier  [1] TerminalIdentifier OPTIONAL,
   private-domain-name  [2] PrivateDomainName OPTIONAL,
   organization-name    [3] OrganizationName OPTIONAL,
   -- see also teletex-organization-name
   numeric-user-identifier      [4] NumericUserIdentifier OPTIONAL,
   personal-name        [5] PersonalName OPTIONAL,
   -- see also teletex-personal-name
   organizational-unit-names    [6] OrganizationalUnitNames OPTIONAL
   -- see also teletex-organizational-unit-names -- }

CountryName ::= [APPLICATION 1] CHOICE { id-qt 1
   x121-dcc-code NumericString
                (SIZE (ub-country-name-numeric-length)),
   iso-3166-alpha2-code PrintableString
                (SIZE (ub-country-name-alpha-length)) }
id-qt-unotice  OBJECT IDENTIFIER

AdministrationDomainName ::= [APPLICATION 2] CHOICE { id-qt 2
   numeric NumericString (SIZE (0..ub-domain-name-length)),
   printable PrintableString (SIZE (0..ub-domain-name-length)) }

NetworkAddress ::= X121Address  -- extended key purpose OIDs
id-kp-serverAuth      OBJECT IDENTIFIER see also extended-network-address

X121Address ::= { id-kp 1 }
id-kp-clientAuth      OBJECT IDENTIFIER NumericString (SIZE (1..ub-x121-address-length))

TerminalIdentifier ::= { id-kp 2 }
id-kp-codeSigning     OBJECT IDENTIFIER PrintableString (SIZE (1..ub-terminal-id-length))

PrivateDomainName ::= CHOICE { id-kp 3
   numeric NumericString (SIZE (1..ub-domain-name-length)),



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   printable PrintableString (SIZE (1..ub-domain-name-length)) }
id-kp-emailProtection OBJECT IDENTIFIER

OrganizationName ::= { id-kp 4 }
id-kp-ipsecEndSystem  OBJECT IDENTIFIER PrintableString
                            (SIZE (1..ub-organization-name-length))
-- see also teletex-organization-name

NumericUserIdentifier ::= { id-kp 5 }
id-kp-ipsecTunnel     OBJECT IDENTIFIER NumericString
                            (SIZE (1..ub-numeric-user-id-length))

PersonalName ::= SET { id-kp 6
   surname [0] PrintableString (SIZE (1..ub-surname-length)),
   given-name [1] PrintableString
                        (SIZE (1..ub-given-name-length)) OPTIONAL,
   initials [2] PrintableString (SIZE (1..ub-initials-length)) OPTIONAL,
   generation-qualifier [3] PrintableString
                (SIZE (1..ub-generation-qualifier-length)) OPTIONAL }
id-kp-ipsecUser       OBJECT IDENTIFIER
-- see also teletex-personal-name

OrganizationalUnitNames ::= { id-kp 7 }
id-kp-timeStamping    OBJECT IDENTIFIER SEQUENCE SIZE (1..ub-organizational-units)
                                        OF OrganizationalUnitName
-- see also teletex-organizational-unit-names

OrganizationalUnitName ::= { id-kp 8 } PrintableString (SIZE
                        (1..ub-organizational-unit-name-length))

-- access descriptors for authority info access extension
id-ad-ocsp      OBJECT IDENTIFIER      Built-in Domain-defined Attributes

BuiltInDomainDefinedAttributes ::= { id-ad 1 }
id-ad-caIssuers OBJECT IDENTIFIER SEQUENCE SIZE
                                (1..ub-domain-defined-attributes) OF
                                BuiltInDomainDefinedAttribute

BuiltInDomainDefinedAttribute ::= SEQUENCE { id-ad 2 }

-- attribute data types
   type PrintableString (SIZE
                        (1..ub-domain-defined-attribute-type-length)),
   value PrintableString (SIZE
                        (1..ub-domain-defined-attribute-value-length))}

--

Attribute      Extension Attributes

ExtensionAttributes ::= SET SIZE (1..ub-extension-attributes) OF
                        ExtensionAttribute

ExtensionAttribute ::=  SEQUENCE {
        type    AttributeValue,
   extension-attribute-type [0] INTEGER (0..ub-extension-attributes),
   extension-attribute-value [1]
                        ANY DEFINED BY extension-attribute-type }

-- Extension types and attribute values



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        values  SET OF AttributeValue


-- at least one value is required -- }

AttributeType

common-name INTEGER ::=   OBJECT IDENTIFIER

AttributeValue 1

CommonName ::=   ANY

AttributeTypeAndValue PrintableString (SIZE (1..ub-common-name-length))

teletex-common-name INTEGER ::=     SEQUENCE 2

TeletexCommonName ::= TeletexString (SIZE (1..ub-common-name-length))

teletex-organization-name INTEGER ::= 3

TeletexOrganizationName ::=
                TeletexString (SIZE (1..ub-organization-name-length))

teletex-personal-name INTEGER ::= 4

TeletexPersonalName ::= SET {
        type    AttributeType,
        value   AttributeValue
   surname [0] TeletexString (SIZE (1..ub-surname-length)),
   given-name [1] TeletexString
                (SIZE (1..ub-given-name-length)) OPTIONAL,
   initials [2] TeletexString (SIZE (1..ub-initials-length)) OPTIONAL,
   generation-qualifier [3] TeletexString (SIZE
                (1..ub-generation-qualifier-length)) OPTIONAL }

-- naming data types --

Name

teletex-organizational-unit-names INTEGER ::=   CHOICE { -- only one possibility for now --
                                 rdnSequence  RDNSequence }

RDNSequence 5

TeletexOrganizationalUnitNames ::= SEQUENCE OF RelativeDistinguishedName

DistinguishedName       ::=   RDNSequence

RelativeDistinguishedName  ::=
                        SET SIZE (1 .. MAX)
        (1..ub-organizational-units) OF AttributeTypeAndValue

-- Directory string type --

DirectoryString TeletexOrganizationalUnitName

TeletexOrganizationalUnitName ::= CHOICE {
        teletexString TeletexString
                        (SIZE (1..MAX)),
        printableString (1..ub-organizational-unit-name-length))

pds-name INTEGER ::= 7

PDSName ::= PrintableString (SIZE (1..MAX)),
        universalString         UniversalString (1..ub-pds-name-length))

physical-delivery-country-name INTEGER ::= 8

PhysicalDeliveryCountryName ::= CHOICE {
   x121-dcc-code NumericString (SIZE (1..MAX)),
        utf8String              UTF8String (ub-country-name-numeric-length)),
   iso-3166-alpha2-code PrintableString
                        (SIZE (1..MAX))
        bmpString               BMPString (SIZE(1..MAX)) (ub-country-name-alpha-length)) }

-- certificate and CRL specific structures begin here

Certificate

postal-code INTEGER ::=  SEQUENCE  {
     tbsCertificate       TBSCertificate,
     signatureAlgorithm   AlgorithmIdentifier,
     signature            BIT STRING  }

TBSCertificate 9

PostalCode ::=  SEQUENCE CHOICE {
     version         [0]  EXPLICIT Version DEFAULT v1,
     serialNumber         CertificateSerialNumber,
     signature            AlgorithmIdentifier,
     issuer               Name,
     validity             Validity,
     subject              Name,
     subjectPublicKeyInfo SubjectPublicKeyInfo,
   numeric-code NumericString (SIZE (1..ub-postal-code-length)),



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     issuerUniqueID  [1]  UniqueIdentifier OPTIONAL,
                          -- If present, version must be v2 or v3
     subjectUniqueID [2]  UniqueIdentifier OPTIONAL,
                          -- If present, version must be v2 or v3
     extensions      [3]  EXPLICIT Extensions OPTIONAL
                          -- If present, version must be v3


   printable-code PrintableString (SIZE (1..ub-postal-code-length)) }

Version

physical-delivery-office-name INTEGER ::= 10

PhysicalDeliveryOfficeName ::= PDSParameter

physical-delivery-office-number INTEGER ::= 11

PhysicalDeliveryOfficeNumber ::= PDSParameter

extension-OR-address-components INTEGER  {  v1(0), v2(1), v3(2)  }

CertificateSerialNumber ::= 12

ExtensionORAddressComponents ::= PDSParameter

physical-delivery-personal-name INTEGER

Validity ::= SEQUENCE {
     notBefore      Time,
     notAfter       Time }

Time 13

PhysicalDeliveryPersonalName ::= CHOICE {
     utcTime        UTCTime,
     generalTime    GeneralizedTime }

UniqueIdentifier PDSParameter

physical-delivery-organization-name INTEGER ::=  BIT STRING

SubjectPublicKeyInfo 14

PhysicalDeliveryOrganizationName ::=  SEQUENCE  {
     algorithm            AlgorithmIdentifier,
     subjectPublicKey     BIT STRING  }

Extensions PDSParameter

extension-physical-delivery-address-components INTEGER ::= 15

ExtensionPhysicalDeliveryAddressComponents ::= PDSParameter

unformatted-postal-address INTEGER ::= 16

UnformattedPostalAddress ::= SET {
   printable-address SEQUENCE SIZE (1..MAX) (1..ub-pds-physical-address-lines) OF Extension

Extension  ::=  SEQUENCE  {
     extnID      OBJECT IDENTIFIER,
     critical    BOOLEAN DEFAULT FALSE,
     extnValue   OCTET STRING
           PrintableString (SIZE (1..ub-pds-parameter-length)) OPTIONAL,
   teletex-string TeletexString
         (SIZE (1..ub-unformatted-address-length)) OPTIONAL }

-- Extension

street-address INTEGER ::= { {id-ce 15}, ... , keyUsage }

ID 17

StreetAddress ::=  OBJECT IDENTIFIER
joint-iso-ccitt       ID PDSParameter

post-office-box-address INTEGER ::=  { 2 }
ds                    ID 18

PostOfficeBoxAddress ::=  {joint-iso-ccitt 5}
id-ce                 ID PDSParameter

poste-restante-address INTEGER ::=  {ds 29}

AuthorityKeyIdentifier 19

PosteRestanteAddress ::= SEQUENCE {
      keyIdentifier             [0] KeyIdentifier            OPTIONAL,
      authorityCertIssuer       [1] GeneralNames             OPTIONAL,
      authorityCertSerialNumber [2] CertificateSerialNumber  OPTIONAL
  }
       ( WITH COMPONENTS       {..., authorityCertIssuer PRESENT,
                                  authorityCertSerialNumber PRESENT} |
        WITH COMPONENTS        {..., authorityCertIssuer ABSENT, PDSParameter

unique-postal-name INTEGER ::= 20




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                                  authorityCertSerialNumber ABSENT} )

KeyIdentifier ::= OCTET STRING

-- subjectKeyIdentifier


UniquePostalName ::= KeyIdentifier

KeyUsage PDSParameter

local-postal-attributes INTEGER ::= BIT STRING {
     digitalSignature        (0),
     nonRepudiation          (1),
     keyEncipherment         (2),
     dataEncipherment        (3),
     keyAgreement            (4),
     keyCertSign             (5),
     cRLSign                 (6) }

id-ce-privateKeyUsagePeriod OBJECT IDENTIFIER 21

LocalPostalAttributes ::=  { id-ce 16 }

PrivateKeyUsagePeriod PDSParameter

PDSParameter ::= SEQUENCE SET {
     notBefore       [0]     GeneralizedTime
   printable-string PrintableString
                (SIZE(1..ub-pds-parameter-length)) OPTIONAL,
     notAfter        [1]     GeneralizedTime
   teletex-string TeletexString
                (SIZE(1..ub-pds-parameter-length)) OPTIONAL }
     ( WITH COMPONENTS       {..., notBefore PRESENT} |
     WITH COMPONENTS         {..., notAfter PRESENT} )

id-ce-certificatePolicies OBJECT IDENTIFIER ::=  { id-ce 32 }

CertificatePolicies

extended-network-address INTEGER ::= SEQUENCE SIZE (1..MAX) OF PolicyInformation

PolicyInformation 22

ExtendedNetworkAddress ::= SEQUENCE CHOICE {
     policyIdentifier   CertPolicyId,
     policyQualifiers
   e163-4-address SEQUENCE SIZE (1..MAX) OF
             PolicyQualifierInfo {
        number [0] NumericString (SIZE (1..ub-e163-4-number-length)),
        sub-address [1] NumericString
                (SIZE (1..ub-e163-4-sub-address-length)) OPTIONAL },
   psap-address [0] PresentationAddress }

CertPolicyId ::= OBJECT IDENTIFIER

PolicyQualifierInfo

PresentationAddress ::= SEQUENCE {
       policyQualifierId  PolicyQualifierId,
       qualifier        ANY DEFINED BY policyQualifierId
        pSelector       [0] EXPLICIT OCTET STRING OPTIONAL,
        sSelector       [1] EXPLICIT OCTET STRING OPTIONAL,
        tSelector       [2] EXPLICIT OCTET STRING OPTIONAL,
        nAddresses      [3] EXPLICIT SET SIZE (1..MAX) OF OCTET STRING }

PolicyQualifierId

terminal-type  INTEGER ::= OBJECT IDENTIFIER

id-ce-policyMappings OBJECT IDENTIFIER 23

TerminalType ::= INTEGER { id-ce 33
   telex (3),
   teletex (4),
   g3-facsimile (5),
   g4-facsimile (6),
   ia5-terminal (7),
   videotex (8) }

PolicyMappings (0..ub-integer-options)

--      Extension Domain-defined Attributes

teletex-domain-defined-attributes INTEGER ::= 6

TeletexDomainDefinedAttributes ::= SEQUENCE SIZE (1..MAX)
   (1..ub-domain-defined-attributes) OF SEQUENCE {
     issuerDomainPolicy      CertPolicyId,
     subjectDomainPolicy     CertPolicyId }

id-ce-subjectAltName OBJECT IDENTIFIER TeletexDomainDefinedAttribute

TeletexDomainDefinedAttribute ::= SEQUENCE { id-ce 17 }
        type TeletexString
               (SIZE (1..ub-domain-defined-attribute-type-length)),
        value TeletexString



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SubjectAltName


               (SIZE (1..ub-domain-defined-attribute-value-length)) }

--  specifications of Upper Bounds must be regarded as mandatory
--  from Annex B of ITU-T X.411 Reference Definition of MTS Parameter
--  Upper Bounds

--      Upper Bounds
ub-name INTEGER ::= GeneralNames

GeneralNames     32768
ub-common-name  INTEGER ::= SEQUENCE SIZE (1..MAX) OF GeneralName

GeneralName     64
ub-locality-name        INTEGER ::= CHOICE {
-- OTHER-NAME     128
ub-state-name   INTEGER ::= TYPE-IDENTIFIER  note: not supported in '88 ASN.1
     otherName                       [0]     AnotherName,
     rfc822Name                      [1]     IA5String,
     dNSName                         [2]     IA5String,
     x400Address                     [3]     ORAddress,
     directoryName                   [4]     Name,
     ediPartyName                    [5]     EDIPartyName,
     uniformResourceIdentifier       [6]     IA5String,
     iPAddress                       [7]     OCTET STRING,
     registeredID                    [8]     OBJECT IDENTIFIER }

AnotherName     128
ub-organization-name    INTEGER ::= SEQUENCE {
     type-id    OBJECT IDENTIFIER,
     value      [0] EXPLICIT ANY DEFINED BY type-id
     }

EDIPartyName     64
ub-organizational-unit-name     INTEGER ::= SEQUENCE {
     nameAssigner            [0]     DirectoryString OPTIONAL,
     partyName               [1]     DirectoryString }

id-ce-issuerAltName OBJECT IDENTIFIER     64
ub-title        INTEGER ::=  { id-ce 18 }

IssuerAltName     64
ub-match        INTEGER ::=     128

ub-emailaddress-length INTEGER ::= 128

ub-common-name-length INTEGER ::= 64
ub-country-name-alpha-length INTEGER ::= 2
ub-country-name-numeric-length INTEGER ::= 3
ub-domain-defined-attributes INTEGER ::= 4
ub-domain-defined-attribute-type-length INTEGER ::= 8
ub-domain-defined-attribute-value-length INTEGER ::= 128
ub-domain-name-length INTEGER ::= 16
ub-extension-attributes INTEGER ::= 256
ub-e163-4-number-length INTEGER ::= 15
ub-e163-4-sub-address-length INTEGER ::= 40
ub-generation-qualifier-length INTEGER ::= 3
ub-given-name-length INTEGER ::= 16
ub-initials-length INTEGER ::= 5
ub-integer-options INTEGER ::= GeneralNames

id-ce-subjectDirectoryAttributes OBJECT IDENTIFIER 256
ub-numeric-user-id-length INTEGER ::=  { id-ce 9 }

SubjectDirectoryAttributes 32
ub-organization-name-length INTEGER ::= SEQUENCE SIZE (1..MAX) OF Attribute

id-ce-basicConstraints OBJECT IDENTIFIER 64
ub-organizational-unit-name-length INTEGER ::=  { id-ce 19 }

BasicConstraints 32
ub-organizational-units INTEGER ::= SEQUENCE {
     cA                      BOOLEAN DEFAULT FALSE,
     pathLenConstraint 4
ub-pds-name-length INTEGER ::= 16
ub-pds-parameter-length INTEGER (0..MAX) OPTIONAL }

id-ce-nameConstraints OBJECT IDENTIFIER ::=  { id-ce 30 }

NameConstraints
ub-pds-physical-address-lines INTEGER ::= SEQUENCE {
     permittedSubtrees       [0]     GeneralSubtrees OPTIONAL,
     excludedSubtrees        [1]     GeneralSubtrees OPTIONAL }

GeneralSubtrees 6
ub-postal-code-length INTEGER ::= SEQUENCE SIZE (1..MAX) OF GeneralSubtree

GeneralSubtree 16
ub-surname-length INTEGER ::= SEQUENCE { 40
ub-terminal-id-length INTEGER ::= 24
ub-unformatted-address-length INTEGER ::= 180
ub-x121-address-length INTEGER ::= 16

-- Note - upper bounds on string types, such as TeletexString, are
-- measured in characters.  Excepting PrintableString or IA5String, a
-- significantly greater number of octets will be required to hold



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     base                    GeneralName,
     minimum         [0]     BaseDistance DEFAULT 0,
     maximum         [1]     BaseDistance OPTIONAL }

BaseDistance ::= INTEGER (0..MAX)

id-ce-policyConstraints OBJECT IDENTIFIER ::=  { id-ce 36 }

PolicyConstraints ::= SEQUENCE SIZE (1..MAX) OF SEQUENCE {
     requireExplicitPolicy           [0] SkipCerts OPTIONAL,
     inhibitPolicyMapping            [1] SkipCerts OPTIONAL }

SkipCerts


-- such a value.  As a minimum, 16 octets, or twice the specified upper
-- bound, whichever is the larger, should be allowed for TeletexString.
-- For UTF8String or UniversalString at least four times the upper
-- bound should be allowed.

END













































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A.2 Implicit Module 88-style ASN.1

PKIX1Implicit88 {iso(1) identified-organization(3) dod(6) internet(1)
  security(5) mechanisms(5) pkix(7) id-mod(0) id-pkix1-implicit-88(2)}

DEFINITIONS IMPLICIT TAGS ::= INTEGER (0..MAX)

BEGIN

-- cRLDistributionPoints CRLDistPointsSyntax EXPORTS ALL --

IMPORTS
        id-pe, id-qt, id-kp, id-ad, id-qt-unotice, id-qt-cps,
                ORAddress, Name, RelativeDistinguishedName,
                CertificateSerialNumber,
                CertificateList, AlgorithmIdentifier, ub-name,
                Attribute, DirectoryString
                FROM PKIX1Explicit88 {iso(1) identified-organization(3)
                dod(6) internet(1) security(5) mechanisms(5) pkix(7)
                id-mod(0) id-pkix1-explicit(1)};


-- ISO arc for standard certificate and CRL extensions

id-ce OBJECT IDENTIFIER  ::=  {joint-iso-ccitt(2) ds(5) 29}

--              SEQUENCE SIZE (1..MAX) OF DistributionPoint

CRLDistPointsSyntax authority key identifier OID and syntax

id-ce-authorityKeyIdentifier OBJECT IDENTIFIER ::= SEQUENCE SIZE (1..MAX) OF DistributionPoint

DistributionPoint  { id-ce 35 }

AuthorityKeyIdentifier ::= SEQUENCE {
     distributionPoint
      keyIdentifier             [0]     DistributionPointName KeyIdentifier            OPTIONAL,
     reasons
      authorityCertIssuer       [1]     ReasonFlags GeneralNames             OPTIONAL,
     cRLIssuer
      authorityCertSerialNumber [2]     GeneralNames CertificateSerialNumber  OPTIONAL }

DistributionPointName ::= CHOICE {
     fullName                [0]     GeneralNames,
     nameRelativeToCRLIssuer [1]     RelativeDistinguishedName }

ReasonFlags
    -- authorityCertIssuer and authorityCertSerialNumber must both
    -- be present or both be absent

KeyIdentifier ::= BIT OCTET STRING {
     unused                  (0),
     keyCompromise           (1),
     cACompromise            (2),
     affiliationChanged      (3),
     superseded              (4),
     cessationOfOperation    (5),
     certificateHold         (6) }

id-ce-extKeyUsage

-- subject key identifier OID and syntax

id-ce-subjectKeyIdentifier OBJECT IDENTIFIER ::= {id-ce 37}

ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId

KeyPurposeId  { id-ce 14 }

SubjectKeyIdentifier ::= KeyIdentifier

-- key usage extension OID and syntax

id-ce-keyUsage OBJECT IDENTIFIER

AuthorityInfoAccessSyntax  ::=
        SEQUENCE SIZE (1..MAX) OF AccessDescription

AccessDescription ::=  SEQUENCE  {
        accessMethod          OBJECT IDENTIFIER, id-ce 15 }



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        accessLocation        GeneralName  }

-- CRL structures

CertificateList


KeyUsage ::=  SEQUENCE  {
     tbsCertList          TBSCertList,
     signatureAlgorithm   AlgorithmIdentifier,
     signature BIT STRING {
     digitalSignature        (0),
     nonRepudiation          (1),
     keyEncipherment         (2),
     dataEncipherment        (3),
     keyAgreement            (4),
     keyCertSign             (5),
     cRLSign                 (6) }

TBSCertList

-- private key usage period extension OID and syntax

id-ce-privateKeyUsagePeriod OBJECT IDENTIFIER ::=  SEQUENCE  {
     version                 Version OPTIONAL,
                                  -- if present, must be v2
     signature               AlgorithmIdentifier,
     issuer                  Name,
     thisUpdate              Time,
     nextUpdate              Time  OPTIONAL,
     revokedCertificates     SEQUENCE OF id-ce 16 }

PrivateKeyUsagePeriod ::= SEQUENCE {
          userCertificate         CertificateSerialNumber,
          revocationDate          Time,
          crlEntryExtensions      Extensions OPTIONAL
                                         -- if present, must be v2
                               }  OPTIONAL,
     crlExtensions
     notBefore       [0]  EXPLICIT Extensions     GeneralizedTime OPTIONAL,
     notAfter        [1]     GeneralizedTime OPTIONAL
                                         -- if present, must be v2 }
     -- Version, Time, CertificateSerialNumber, and Extensions were either notBefore or notAfter must be present

-- defined earlier for use in the certificate structure

AlgorithmIdentifier policies extension OID and syntax

id-ce-certificatePolicies OBJECT IDENTIFIER ::=  { id-ce 32 }

CertificatePolicies ::= SEQUENCE SIZE (1..MAX) OF PolicyInformation

PolicyInformation ::= SEQUENCE {
     algorithm
     policyIdentifier   CertPolicyId,
     policyQualifiers   SEQUENCE SIZE (1..MAX) OF
             PolicyQualifierInfo OPTIONAL }

CertPolicyId ::= OBJECT IDENTIFIER,
     parameters IDENTIFIER

PolicyQualifierInfo ::= SEQUENCE {
       policyQualifierId  PolicyQualifierId,
       qualifier        ANY DEFINED BY algorithm OPTIONAL policyQualifierId }

-- contains a value of the type Implementations that recognize additional policy qualifiers must
-- registered for use with augment the
                                -- algorithm object identifier value


id-ce-cRLNumber following definition for PolicyQualifierId

PolicyQualifierId ::=
    OBJECT IDENTIFIER ::= { id-ce 20 }

CRLNumber ::= INTEGER (0..MAX)

id-ce-issuingDistributionPoint ( id-qt-cps | id-qt-unotice )

-- CPS pointer qualifier

id-qt-cps      OBJECT IDENTIFIER ::=  { id-ce 28 id-qt 1 }

IssuingDistributionPoint

CPSuri ::= SEQUENCE {
     distributionPoint       [0] DistributionPointName OPTIONAL,
     onlyContainsUserCerts   [1] BOOLEAN DEFAULT FALSE,
     onlyContainsCACerts     [2] BOOLEAN DEFAULT FALSE,
     onlySomeReasons         [3] ReasonFlags OPTIONAL, IA5String

-- user notice qualifier



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     indirectCRL             [4] BOOLEAN DEFAULT FALSE }


id-ce-deltaCRLIndicator


id-qt-unotice  OBJECT IDENTIFIER ::=  { id-ce 27 id-qt 2 }

-- deltaCRLIndicator ::= BaseCRLNumber

id-ce-cRLNumber OBJECT IDENTIFIER

UserNotice ::= SEQUENCE { id-ce 20 }

BaseCRLNumber ::= CRLNumber

id-ce-cRLReasons OBJECT IDENTIFIER
     noticeRef        NoticeReference OPTIONAL,
     explicitText     DisplayText OPTIONAL}

NoticeReference ::= SEQUENCE { id-ce 21
     organization     DisplayText,
     noticeNumbers    SEQUENCE OF INTEGER }

CRLReason

DisplayText ::= ENUMERATED CHOICE {
     unspecified             (0),
     keyCompromise           (1),
     cACompromise            (2),
     affiliationChanged      (3),
     superseded              (4),
     cessationOfOperation    (5),
     certificateHold         (6),
     removeFromCRL           (8)
     visibleString    VisibleString  (SIZE (1..200)),
     bmpString        BMPString      (SIZE (1..200)),
     utf8String       UTF8String     (SIZE (1..200)) }

id-ce-certificateIssuer

-- policy mapping extension OID and syntax

id-ce-policyMappings OBJECT IDENTIFIER ::=  { id-ce 29 33 }

CertificateIssuer ::= GeneralNames

id-ce-holdInstructionCode OBJECT IDENTIFIER

PolicyMappings ::= SEQUENCE SIZE (1..MAX) OF SEQUENCE { id-ce 23
     issuerDomainPolicy      CertPolicyId,
     subjectDomainPolicy     CertPolicyId }

HoldInstructionCode ::=

-- subject alternative name extension OID and syntax

id-ce-subjectAltName OBJECT IDENTIFIER

-- ANSI x9 arc holdinstruction arc

member-body ID ::=  { iso 2 id-ce 17 }
us ID

SubjectAltName ::= { member-body 840 }
x9cm ID GeneralNames

GeneralNames ::= SEQUENCE SIZE (1..MAX) OF GeneralName

GeneralName ::= CHOICE { us 10040
     otherName                       [0]     AnotherName,
     rfc822Name                      [1]     IA5String,
     dNSName                         [2]     IA5String,
     x400Address                     [3]     ORAddress,
     directoryName                   [4]     Name,
     ediPartyName                    [5]     EDIPartyName,
     uniformResourceIdentifier       [6]     IA5String,
     iPAddress                       [7]     OCTET STRING,
     registeredID                    [8]     OBJECT IDENTIFIER }
holdInstruction ID ::= {x9cm 2}

-- ANSI X9 holdinstructions referenced by this standard

id-holdinstruction-none ID ::= {holdInstruction 1}
id-holdinstruction-callissuer ID ::= {holdInstruction 2}
id-holdinstruction-reject ID AnotherName replaces OTHER-NAME ::= {holdInstruction 3}

id-ce-invalidityDate OBJECT IDENTIFIER TYPE-IDENTIFIER, as
-- TYPE-IDENTIFIER is not supported in the '88 ASN.1 syntax

AnotherName ::= SEQUENCE { id-ce 24
     type-id    OBJECT IDENTIFIER,
     value      [0] EXPLICIT ANY DEFINED BY type-id }

InvalidityDate ::=  GeneralizedTime



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-- Algorithm structures

     md2WithRSAEncryption OBJECT IDENTIFIER


EDIPartyName ::= SEQUENCE {
         iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1)
         pkcs-1(1) 2
     nameAssigner            [0]     DirectoryString OPTIONAL,
     partyName               [1]     DirectoryString }

     md5WithRSAEncryption

-- issuer alternative name extension OID and syntax

id-ce-issuerAltName OBJECT IDENTIFIER ::=  {
         iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1)
         pkcs-1(1) 4 id-ce 18 }

     sha1WithRSASignature

IssuerAltName ::= GeneralNames

id-ce-subjectDirectoryAttributes OBJECT IDENTIFIER ::=  {
         iso(1) identified-organization(3) oiw(14) secsig(3)
         algorithm(2) 29 id-ce 9 }

     id-dsa-with-sha1 ID

SubjectDirectoryAttributes ::= SEQUENCE SIZE (1..MAX) OF Attribute

-- basic constraints extension OID and syntax

id-ce-basicConstraints OBJECT IDENTIFIER ::=  {
                iso(1) member-body(2) us(840) x9-57 (10040)
                x9algorithm(4) 3 id-ce 19 }

     Dss-Sig-Value

BasicConstraints ::= SEQUENCE {
                r       INTEGER,
                s
     cA                      BOOLEAN DEFAULT FALSE,
     pathLenConstraint       INTEGER (0..MAX) OPTIONAL }

     pkcs-1

-- name constraints extension OID and syntax

id-ce-nameConstraints OBJECT IDENTIFIER ::=  { iso(1) member-body(2) us(840)
                    rsadsi(113549) pkcs(1) 1 id-ce 30 }

     rsaEncryption OBJECT IDENTIFIER ::=  { pkcs-1 1}

     dhpublicnumber OBJECT IDENTIFIER

NameConstraints ::= SEQUENCE { iso(1) member-body(2)
               us(840) ansi-x942(10046) number-type(2) 1
     permittedSubtrees       [0]     GeneralSubtrees OPTIONAL,
     excludedSubtrees        [1]     GeneralSubtrees OPTIONAL }

     DHParameter

GeneralSubtrees ::= SEQUENCE SIZE (1..MAX) OF GeneralSubtree

GeneralSubtree ::= SEQUENCE {
          prime INTEGER, -- p
     base                    GeneralName,
     minimum         [0]     BaseDistance DEFAULT 0,
     maximum         [1]     BaseDistance OPTIONAL }

BaseDistance ::= INTEGER (0..MAX)

-- g
                }

     id-dsa ID policy constraints extension OID and syntax

id-ce-policyConstraints OBJECT IDENTIFIER ::=  { iso(1) member-body(2) us(840) x9-57(10040)
                x9algorithm(4) 1 id-ce 36 }

     Dss-Parms

PolicyConstraints ::= SEQUENCE SIZE (1..MAX) OF SEQUENCE {
         p             INTEGER,
         q             INTEGER,
         g             INTEGER  }

     id-keyEncryptionAlgorithm  OBJECT IDENTIFIER   ::=
          { 2 16 840 1 101 2 1 1 22
     requireExplicitPolicy           [0] SkipCerts OPTIONAL,
     inhibitPolicyMapping            [1] SkipCerts OPTIONAL }

     KEA-Parms-Id

SkipCerts ::= OCTET STRING INTEGER (0..MAX)



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id-ce-subjectKeyIdentifier


-- CRL distribution points extension OID and syntax

id-ce-cRLDistributionPoints     OBJECT IDENTIFIER  ::=  {id-ce 31}

CRLDistPointsSyntax ::= SEQUENCE SIZE (1..MAX) OF DistributionPoint

DistributionPoint ::= SEQUENCE { id-ce 14
     distributionPoint       [0]     DistributionPointName OPTIONAL,
     reasons                 [1]     ReasonFlags OPTIONAL,
     cRLIssuer               [2]     GeneralNames OPTIONAL }
id-ce-keyUsage

DistributionPointName ::= CHOICE {
     fullName                [0]     GeneralNames,
     nameRelativeToCRLIssuer [1]     RelativeDistinguishedName }

ReasonFlags ::= BIT STRING {
     unused                  (0),
     keyCompromise           (1),
     cACompromise            (2),
     affiliationChanged      (3),
     superseded              (4),
     cessationOfOperation    (5),
     certificateHold         (6) }

-- extended key usage extension OID and syntax

id-ce-extKeyUsage OBJECT IDENTIFIER ::= {id-ce 37}

ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId

KeyPurposeId ::= OBJECT IDENTIFIER

-- extended key purpose OIDs
id-kp-serverAuth      OBJECT IDENTIFIER ::= { id-ce 15 id-kp 1 }
id-ce-authorityKeyIdentifier
id-kp-clientAuth      OBJECT IDENTIFIER ::= { id-ce 35 id-kp 2 }

CPSuri ::= IA5String

UserNotice
id-kp-codeSigning     OBJECT IDENTIFIER ::= CHOICE {
  visibleString     VisibleString,
  bmpString         BMPString id-kp 3 }

PresentationAddress
id-kp-emailProtection OBJECT IDENTIFIER ::= SEQUENCE {
        pSelector       [0] EXPLICIT OCTET STRING OPTIONAL,
        sSelector       [1] EXPLICIT OCTET STRING OPTIONAL,
        tSelector       [2] EXPLICIT OCTET STRING OPTIONAL,
        nAddresses      [3] EXPLICIT SET SIZE (1..MAX) OF OCTET STRING}

-- x400 address syntax starts here
--      OR Names

ORAddressAndOrDirectoryName id-kp 4 }
id-kp-ipsecEndSystem  OBJECT IDENTIFIER ::= ORName

ORAddressAndOptionalDirectoryName { id-kp 5 }
id-kp-ipsecTunnel     OBJECT IDENTIFIER ::= ORName

ORName { id-kp 6 }
id-kp-ipsecUser       OBJECT IDENTIFIER ::= [APPLICATION 0] SEQUENCE {
   -- address -- COMPONENTS OF ORAddress,
   directory-name [0] Name OPTIONAL id-kp 7 }

ORAddress
id-kp-timeStamping    OBJECT IDENTIFIER ::= SEQUENCE {
   built-in-standard-attributes BuiltInStandardAttributes,
   built-in-domain-defined-attributes
                        BuiltInDomainDefinedAttributes OPTIONAL,
   -- see also teletex-domain-defined-attributes
   extension-attributes ExtensionAttributes OPTIONAL id-kp 8 }

--      The OR-address is semantically absent from the OR-name if the
--      built-in-standard-attribute sequence is empty and the
--      built-in-domain-defined-attributes CRL number extension OID and extension-attributes are
--      both omitted.

--      Built-in Standard Attributes
BuiltInStandardAttributes syntax

id-ce-cRLNumber OBJECT IDENTIFIER ::= SEQUENCE {
   country-name CountryName OPTIONAL,
   administration-domain-name AdministrationDomainName OPTIONAL,
   network-address      [0] NetworkAddress OPTIONAL,
   -- see also extended-network-address
   terminal-identifier  [1] TerminalIdentifier OPTIONAL,
   private-domain-name  [2] PrivateDomainName OPTIONAL,
   organization-name    [3] OrganizationName OPTIONAL, id-ce 20 }

CRLNumber ::= INTEGER (0..MAX)




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-- see also teletex-organization-name
   numeric-user-identifier      [4] NumericUserIdentifier issuing distribution point extension OID and syntax

id-ce-issuingDistributionPoint OBJECT IDENTIFIER ::= { id-ce 28 }

IssuingDistributionPoint ::= SEQUENCE {
     distributionPoint       [0] DistributionPointName OPTIONAL,
   personal-name        [5] PersonalName
     onlyContainsUserCerts   [1] BOOLEAN DEFAULT FALSE,
     onlyContainsCACerts     [2] BOOLEAN DEFAULT FALSE,
     onlySomeReasons         [3] ReasonFlags OPTIONAL,
     indirectCRL             [4] BOOLEAN DEFAULT FALSE }


id-ce-deltaCRLIndicator OBJECT IDENTIFIER ::= { id-ce 27 }

-- see also teletex-personal-name
   organizational-unit-names    [6] OrganizationalUnitNames OPTIONAL
   -- see also teletex-organizational-unit-names deltaCRLIndicator ::= BaseCRLNumber

BaseCRLNumber ::= CRLNumber

-- }

CountryName CRL reasons extension OID and syntax

id-ce-cRLReasons OBJECT IDENTIFIER ::= [APPLICATION 1] CHOICE {
   x121-dcc-code NumericString
                (SIZE (ub-country-name-numeric-length)),
   iso-3166-alpha2-code PrintableString
                (SIZE (ub-country-name-alpha-length)) id-ce 21 }

AdministrationDomainName

CRLReason ::= [APPLICATION 2] CHOICE ENUMERATED {
   numeric NumericString (SIZE (0..ub-domain-name-length)),
   printable PrintableString (SIZE (0..ub-domain-name-length))
     unspecified             (0),
     keyCompromise           (1),
     cACompromise            (2),
     affiliationChanged      (3),
     superseded              (4),
     cessationOfOperation    (5),
     certificateHold         (6),
     removeFromCRL           (8) }

-- certificate issuer CRL entry extension OID and syntax

id-ce-certificateIssuer OBJECT IDENTIFIER ::= { id-ce 29 }

NetworkAddress

CertificateIssuer ::= X121Address GeneralNames

-- see also extended-network-address

X121Address ::= NumericString (SIZE (1..ub-x121-address-length))

TerminalIdentifier ::= PrintableString (SIZE (1..ub-terminal-id-length))

PrivateDomainName hold instruction extension OID and syntax

id-ce-holdInstructionCode OBJECT IDENTIFIER ::= CHOICE {
   numeric NumericString (SIZE (1..ub-domain-name-length)),
   printable PrintableString (SIZE (1..ub-domain-name-length)) id-ce 23 }

OrganizationName

HoldInstructionCode ::= PrintableString
                            (SIZE (1..ub-organization-name-length)) OBJECT IDENTIFIER

-- see also teletex-organization-name

NumericUserIdentifier ANSI x9 holdinstructions

-- ANSI x9 arc holdinstruction arc
holdInstruction OBJECT IDENTIFIER ::= NumericString
                            (SIZE (1..ub-numeric-user-id-length))

PersonalName



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            {joint-iso-itu-t(2) member-body(2) us(840) x9cm(10040) 2}

-- ANSI X9 holdinstructions referenced by this standard
id-holdinstruction-none OBJECT IDENTIFIER  ::= SET {
   surname [0] PrintableString (SIZE (1..ub-surname-length)),
   given-name [1] PrintableString
                        (SIZE (1..ub-given-name-length)) OPTIONAL,
   initials [2] PrintableString (SIZE (1..ub-initials-length)) OPTIONAL,
   generation-qualifier [3] PrintableString
                (SIZE (1..ub-generation-qualifier-length)) OPTIONAL}
                {holdInstruction 1} -- see also teletex-personal-name

OrganizationalUnitNames deprecated
id-holdinstruction-callissuer OBJECT IDENTIFIER ::= SEQUENCE SIZE (1..ub-organizational-units)
                                        OF OrganizationalUnitName
                {holdInstruction 2}
id-holdinstruction-reject OBJECT IDENTIFIER ::=
                {holdInstruction 3}

-- see also teletex-organizational-unit-names invalidty date CRL entry extension OID and syntax

id-ce-invalidityDate OBJECT IDENTIFIER ::= { id-ce 24 }

InvalidityDate ::=  GeneralizedTime

END


































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OrganizationalUnitName


Appendix B. 1993 ASN.1 Structures and OIDs


B.1 1993 Explicitly Tagged Module

PKIX1Explicit93 {iso(1) identified-organization(3) dod(6) internet(1)
   security(5) mechanisms(5) pkix(7) id-mod(0) id-pkix1-explicit-93(3)}


DEFINITIONS EXPLICIT TAGS ::= PrintableString (SIZE
                        (1..ub-organizational-unit-name-length))

BEGIN

--      Built-in Domain-defined Attributes
BuiltInDomainDefinedAttributes EXPORTS ALL --

IMPORTS
        authorityKeyIdentifier, subjectKeyIdentifier, keyUsage,
           extendedKeyUsage,privateKeyUsagePeriod, certificatePolicies,
           policyMappings, subjectAltName, issuerAltName,
           basicConstraints, nameConstraints, policyConstraints,
           cRLDistributionPoints, subjectDirectoryAttributes,
           cRLNumber, reasonCode, instructionCode, invalidityDate,
           issuingDistributionPoint, certificateIssuer,
           deltaCRLIndicator, authorityInfoAccess, id-ce
           FROM PKIX1Implicit93 {iso(1) identified-organization(3)
           dod(6) internet(1) security(5) mechanisms(5) pkix(7)
           id-mod(0) id-pkix1-implicit-93(4)} ;

--
                   --  Locally defined OIDs  --

id-pkix  OBJECT IDENTIFIER  ::= SEQUENCE SIZE
                                (1..ub-domain-defined-attributes) OF
                                BuiltInDomainDefinedAttribute

BuiltInDomainDefinedAttribute
         { iso(1) identified-organization(3) dod(6) internet(1)
                    security(5) mechanisms(5) pkix(7) }

-- PKIX arcs
-- arc for private certificate extensions
id-pe OBJECT IDENTIFIER  ::=  { id-pkix 1 }
 -- arc for policy qualifier types
id-qt OBJECT IDENTIFIER ::= SEQUENCE {
   type PrintableString (SIZE
                        (1..ub-domain-defined-attribute-type-length)),
   value PrintableString (SIZE
                        (1..ub-domain-defined-attribute-value-length))} id-pkix 2 }
--      Extension Attributes
ExtensionAttributes ::= SET SIZE (1..ub-extension-attributes) OF
                        ExtensionAttribute
ExtensionAttribute arc for extended key purpose OIDS
id-kp OBJECT IDENTIFIER ::= EXTENSION-ATTRIBUTE

EXTENSION-ATTRIBUTE { id-pkix 3 }
-- arc for access descriptors
id-ad OBJECT IDENTIFIER ::= SEQUENCE {
   extension-attribute-type [0] INTEGER (0..ub-extension-attributes),
   extension-attribute-value [1] ANY DEFINED BY extension-attribute-type id-pkix 48 }

extensionAttributeTable EXTENSION-ATTRIBUTE

-- policyQualifierIds for Internet policy qualifiers
id-qt-cps      OBJECT IDENTIFIER ::=  {
   common-name |
   teletex-common-name |
   teletex-organization-name |
   teletex-personal-name |
   teletex-organizational-unit-names |
   teletex-domain-defined-attributes |
   pds-name |
   physical-delivery-country-name |
   postal-code |
   physical-delivery-office-name |
   physical-delivery-office-number |
   extension-OR-address-components |
   physical-delivery-personal-name |
   physical-delivery-organization-name |
   extension-physical-delivery-address-components |
   unformatted-postal-address |
   street-address |
   post-office-box-address |
   poste-restante-address |
   unique-postal-name |
   local-postal-attributes |
   extended-network-address |
   terminal-type id-qt 1 }
        -- OID for CPS qualifier



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--      Extension Standard Attributes

common-name EXTENSION-ATTRIBUTE ::= {CommonName IDENTIFIED BY 1}

CommonName ::= PrintableString (SIZE (1..ub-common-name-length))

teletex-common-name EXTENSION-ATTRIBUTE


id-qt-unotice  OBJECT IDENTIFIER ::=
                {TeletexCommonName IDENTIFIED BY  { id-qt 2 }
        -- OID for user notice qualifier

-- based on excerpts from AuthenticationFramework
--    {joint-iso-ccitt ds(5) modules(1) authenticationFramework(7) 2}

TeletexCommonName ::= TeletexString (SIZE (1..ub-common-name-length))

teletex-organization-name EXTENSION-ATTRIBUTE ::=
                {TeletexOrganizationName IDENTIFIED BY 3}

TeletexOrganizationName ::=
                TeletexString (SIZE (1..ub-organization-name-length))

teletex-personal-name EXTENSION-ATTRIBUTE ::=
                {TeletexPersonalName IDENTIFIED BY 4}

TeletexPersonalName

               -- Public Key Certificate --

Certificate            ::= SET   SIGNED {
   surname SEQUENCE {
   version                 [0] TeletexString (SIZE (1..ub-surname-length)),
   given-name   Version DEFAULT v1,
   serialNumber                  CertificateSerialNumber,
   signature                     AlgorithmIdentifier,
   issuer                        Name,
   validity                      Validity,
   subject                       Name,
   subjectPublicKeyInfo          SubjectPublicKeyInfo,
   issuerUniqueIdentifier  [1] TeletexString
                           (SIZE (1..ub-given-name-length))   IMPLICIT UniqueIdentifier OPTIONAL,
   initials
                              ---if present, version must be v2 or v3--
   subjectUniqueIdentifier [2] TeletexString (SIZE (1..ub-initials-length))   IMPLICIT UniqueIdentifier OPTIONAL,
   generation-qualifier
                              ---if present, version must be v2 or v3--
   extensions              [3] TeletexString (SIZE
                        (1..ub-generation-qualifier-length))   Extensions OPTIONAL
                              --if present, version must be v3--}  }

teletex-organizational-unit-names EXTENSION-ATTRIBUTE

UniqueIdentifier        ::=
   {TeletexOrganizationalUnitNames IDENTIFIED BY 5}

TeletexOrganizationalUnitNames  BIT STRING

Version                 ::= SEQUENCE SIZE
        (1..ub-organizational-units) OF TeletexOrganizationalUnitName

TeletexOrganizationalUnitName  INTEGER { v1(0), v2(1), v3(2) }

CertificateSerialNumber ::= TeletexString
                        (SIZE (1..ub-organizational-unit-name-length))

pds-name EXTENSION-ATTRIBUTE  INTEGER

Validity                        ::= {PDSName IDENTIFIED BY 7}

PDSName     SEQUENCE {
   notBefore            Time,
   notAfter             Time }

Time ::= PrintableString (SIZE (1..ub-pds-name-length))

physical-delivery-country-name EXTENSION-ATTRIBUTE CHOICE {
        utcTime         UTCTime,
        generalTime             GeneralizedTime }

SubjectPublicKeyInfo    ::=
   {PhysicalDeliveryCountryName IDENTIFIED BY 8}

PhysicalDeliveryCountryName     SEQUENCE{
   algorithm            AlgorithmIdentifier,
   subjectPublicKey     BIT STRING}

Extensions        ::= CHOICE   SEQUENCE SIZE (1..MAX) OF Extension

Extension         ::=   SEQUENCE {
   x121-dcc-code NumericString (SIZE (ub-country-name-numeric-length)),
   iso-3166-alpha2-code PrintableString
                        (SIZE (ub-country-name-alpha-length))
   extnId            EXTENSION.&id ({ExtensionSet}),
   critical          BOOLEAN DEFAULT FALSE,
   extnValue         OCTET STRING }
                -- contains a DER encoding of a value of type



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postal-code EXTENSION-ATTRIBUTE ::= {PostalCode IDENTIFIED BY 9}

PostalCode


                -- &ExtnType for the
                -- extension object identified by extnId --

-- The following information object set is defined to constrain the
-- set of legal certificate extensions.

ExtensionSet    EXTENSION       ::= CHOICE  {
   numeric-code NumericString (SIZE (1..ub-postal-code-length)),
   printable-code PrintableString (SIZE (1..ub-postal-code-length)) authorityKeyIdentifier |
                                            subjectKeyIdentifier |
                                            keyUsage |
                                            extendedKeyUsage |
                                            privateKeyUsagePeriod |
                                            certificatePolicies |
                                            policyMappings |
                                            subjectAltName |
                                            issuerAltName |
                                            basicConstraints |
                                            nameConstraints |
                                            policyConstraints |
                                            cRLDistributionPoints |
                                            subjectDirectoryAttributes |
                                            authorityInfoAccess }

physical-delivery-office-name EXTENSION-ATTRIBUTE ::=
                        {PhysicalDeliveryOfficeName IDENTIFIED BY 10}

PhysicalDeliveryOfficeName ::= PDSParameter

physical-delivery-office-number EXTENSION-ATTRIBUTE ::=
   {PhysicalDeliveryOfficeNumber IDENTIFIED BY 11}

PhysicalDeliveryOfficeNumber ::= PDSParameter

extension-OR-address-components EXTENSION-ATTRIBUTE ::=
   {ExtensionORAddressComponents IDENTIFIED BY 12}

ExtensionORAddressComponents ::= PDSParameter

physical-delivery-personal-name EXTENSION-ATTRIBUTE ::=
   {PhysicalDeliveryPersonalName IDENTIFIED BY 13}

PhysicalDeliveryPersonalName ::= PDSParameter

physical-delivery-organization-name EXTENSION-ATTRIBUTE ::=
   {PhysicalDeliveryOrganizationName IDENTIFIED BY 14}

PhysicalDeliveryOrganizationName ::= PDSParameter

extension-physical-delivery-address-components EXTENSION-ATTRIBUTE ::=
   {ExtensionPhysicalDeliveryAddressComponents IDENTIFIED BY 15}

ExtensionPhysicalDeliveryAddressComponents ::= PDSParameter

unformatted-postal-address EXTENSION-ATTRIBUTE

EXTENSION       ::=
                        {UnformattedPostalAddress     CLASS {
   &id          OBJECT IDENTIFIER UNIQUE,
   &ExtnType }
WITH SYNTAX  {
   SYNTAX               &ExtnType
   IDENTIFIED BY 16}

UnformattedPostalAddress        &id }

                  -- Certificate Revocation List --

CertificateList ::= SET    SIGNED {
   printable-address SEQUENCE SIZE (1..ub-pds-physical-address-lines) OF
           PrintableString (SIZE (1..ub-pds-parameter-length)) {
   version                Version  OPTIONAL,
   teletex-string TeletexString (SIZE
                         (1..ub-unformatted-address-length)) -- if present, must be v2
   signature              AlgorithmIdentifier,
   issuer                 Name,
   thisUpdate             Time,
   nextUpdate             Time OPTIONAL,
   revokedCertificates    SEQUENCE OF SEQUENCE {
   userCertificate        CertificateSerialNumber,
   revocationDate         Time,
   crlEntryExtensions     EntryExtensions OPTIONAL }

street-address EXTENSION-ATTRIBUTE OPTIONAL,
   crlExtensions          [0]   CRLExtensions OPTIONAL }}

CRLExtensions        ::=
                {StreetAddress IDENTIFIED BY 17}        SEQUENCE SIZE (1..MAX) OF CRLExtension

CRLExtension         ::=        SEQUENCE {
   extnId            EXTENSION.&id ({CRLExtensionSet}),
   critical          BOOLEAN DEFAULT FALSE,



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StreetAddress ::= PDSParameter

post-office-box-address EXTENSION-ATTRIBUTE ::=
                {PostOfficeBoxAddress IDENTIFIED BY 18}

PostOfficeBoxAddress ::= PDSParameter

poste-restante-address EXTENSION-ATTRIBUTE ::=
                {PosteRestanteAddress IDENTIFIED BY 19}

PosteRestanteAddress ::= PDSParameter

unique-postal-name EXTENSION-ATTRIBUTE ::=
                {UniquePostalName IDENTIFIED BY 20}

UniquePostalName ::= PDSParameter

local-postal-attributes EXTENSION-ATTRIBUTE


   extnValue         OCTET STRING }
                -- contains a DER encoding of a value of type
                -- &ExtnType for the
                -- extension object identified by extnId --

-- The following information object set is defined to constrain the
-- set of legal CRL extensions.

CRLExtensionSet EXTENSION       ::=
                {LocalPostalAttributes IDENTIFIED BY 21}

LocalPostalAttributes     { authorityKeyIdentifier |
                                             issuerAltName |
                                             cRLNumber |
                                             deltaCRLIndicator |
                                             issuingDistributionPoint }

-- EXTENSION defined above for certificates

EntryExtensions        ::= PDSParameter

PDSParameter      SEQUENCE SIZE (1..MAX) OF EntryExtension

EntryExtension         ::= SET      SEQUENCE {
   printable-string PrintableString
                (SIZE(1..ub-pds-parameter-length)) OPTIONAL,
   teletex-string TeletexString
                (SIZE(1..ub-pds-parameter-length)) OPTIONAL
   extnId            EXTENSION.&id ({EntryExtensionSet}),
   critical          BOOLEAN DEFAULT FALSE,
   extnValue         OCTET STRING }

extended-network-address EXTENSION-ATTRIBUTE ::=
                        {ExtendedNetworkAddress IDENTIFIED BY 22}

ExtendedNetworkAddress
                -- contains a DER encoding of a value of type
                -- &ExtnType for the
                -- extension object identified by extnId --

-- The following information object set is defined to constrain the
-- set of legal CRL entry extensions.

EntryExtensionSet       EXTENSION       ::= CHOICE     {

   e163-4-address SEQUENCE reasonCode |
                                                instructionCode |
                                                invalidityDate |
                                                certificateIssuer }

         -- information object classes used in the defintion --
                    -- of certificates and CRLs --

-- Parameterized Type SIGNED --

  SIGNED {
        number [0] NumericString (SIZE (1..ub-e163-4-number-length)),
        sub-address [1] NumericString
                (SIZE (1..ub-e163-4-sub-address-length)) OPTIONAL },
        psap-address [0] PresentationAddress ToBeSigned }

terminal-type EXTENSION-ATTRIBUTE ::= {TerminalType IDENTIFIED BY 23}

TerminalType ::= INTEGER SEQUENCE {
   telex (3),
   teletex (4),
   g3-facsimile (5),
   g4-facsimile (6),
   ia5-terminal (7),
   videotex (8)
     toBeSigned  ToBeSigned,
     algorithm   AlgorithmIdentifier,
     signature   BIT STRING
  } (0..ub-integer-options)

-- Definition of AlgorithmIdentifier
-- ISO definition was:
--



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--      Extension Domain-defined Attributes

teletex-domain-defined-attributes EXTENSION-ATTRIBUTE ::=
   {TeletexDomainDefinedAttributes IDENTIFIED BY 6}

TeletexDomainDefinedAttributes AlgorithmIdentifier     ::=  SEQUENCE SIZE
   (1..ub-domain-defined-attributes) OF TeletexDomainDefinedAttribute

TeletexDomainDefinedAttribute {
--   algorithm          ALGORITHM.&id({SupportedAlgorithms}),
--   parameters         ALGORITHM.&Type({SupportedAlgorithms}
--                                         { @algorithm}) OPTIONAL }
-- Definition of ALGORITHM
-- ALGORITHM    ::=     TYPE-IDENTIFIER

-- The following PKIX definition replaces the X.509 definition
--

AlgorithmIdentifier     ::=  SEQUENCE {
        type TeletexString
               (SIZE (1..ub-domain-defined-attribute-type-length)),
        value TeletexString
               (SIZE (1..ub-domain-defined-attribute-value-length))
   algorithm            ALGORITHM-ID.&id({SupportedAlgorithms}),
   parameters           ALGORITHM-ID.&Type({SupportedAlgorithms}
                                           { @algorithm}) OPTIONAL }

--  specifications Definition of Upper Bounds ALGORITHM-ID

 ALGORITHM-ID ::= CLASS {
     &id    OBJECT IDENTIFIER UNIQUE,
     &Type  OPTIONAL
  }
     WITH SYNTAX { OID &id [PARMS &Type] }

--  must The definition of SupportedAlgorithms may be regarded modified as mandatory this
--  from Annex B of ITU-T X.411 document does not specify a mandatory algorithm set.  In addition,
--  Reference Definition of MTS Parameter Upper Bounds the set is specified as extensible, since additional algorithms
--      Upper Bounds
ub-common-name-length INTEGER ::= 64
ub-country-name-alpha-length INTEGER ::= 2
ub-country-name-numeric-length INTEGER ::= 3
ub-domain-defined-attributes INTEGER ::= 4
ub-domain-defined-attribute-type-length INTEGER ::= 8
ub-domain-defined-attribute-value-length INTEGER ::= 128
ub-domain-name-length INTEGER may be supported

SupportedAlgorithms     ALGORITHM-ID  ::= 16
ub-extension-attributes INTEGER       { ..., -- extensible
                                            RsaPublicKey |
                                            RsaSHA-1  |
                                            RsaMD5 |
                                            RsaMD2 |
                                            DssPublicKey |
                                            DsaSHA-1 |
                                            Dhpublicnumber }

-- OIDs and parameter structures for ALGORITHM-IDs used
-- in this specification

RsaPublicKey ALGORITHM-ID ::= 256
ub-e163-4-number-length INTEGER { OID rsaEncryption PARMS NULL }

RsaSHA-1 ALGORITHM-ID ::= 15
ub-e163-4-sub-address-length INTEGER { OID sha1WithRSAEncryption PARMS NULL }

RsaMD5 ALGORITHM-ID ::= 40
ub-generation-qualifier-length INTEGER { OID md5WithRSAEncryption PARMS NULL  }

RsaMD2 ALGORITHM-ID ::= 3
ub-given-name-length INTEGER { OID md2WithRSAEncryption PARMS NULL  }




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DssPublicKey ALGORITHM-ID ::= 16
ub-initials-length INTEGER { OID id-dsa PARMS Dss-Parms }

DsaSHA-1 ALGORITHM-ID ::= 5
ub-integer-options INTEGER { OID id-dsa-with-sha1 PARMS NULL }

DhPublicKey ALGORITHM-ID ::= 256
ub-numeric-user-id-length INTEGER {OID dhpublicnumber PARMS DomainParameters}

-- algorithm identifiers and parameter structures

pkcs-1 OBJECT IDENTIFIER ::= 32
ub-organization-name-length INTEGER {
     iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 1 }

rsaEncryption OBJECT IDENTIFIER ::= 64
ub-organizational-unit-name-length INTEGER  { pkcs-1 1 }

md2WithRSAEncryption OBJECT IDENTIFIER  ::= 32
ub-organizational-units INTEGER  { pkcs-1 2 }

md5WithRSAEncryption OBJECT IDENTIFIER  ::=  { pkcs-1 4
ub-pds-name-length INTEGER ::= 16
ub-pds-parameter-length INTEGER ::= 30
ub-pds-physical-address-lines INTEGER ::= 6
ub-postal-code-length INTEGER }

sha1WithRSAEncryption OBJECT IDENTIFIER  ::= 16
ub-surname-length INTEGER  { pkcs-1 5 }

id-dsa-with-sha1 OBJECT IDENTIFIER ::= 40
ub-terminal-id-length INTEGER  {
     iso(1) member-body(2) us(840) x9-57 (10040) x9algorithm(4) 3 }

Dss-Sig-Value  ::= 24
ub-unformatted-address-length  SEQUENCE  {
     r       INTEGER,
     s       INTEGER  }

dhpublicnumber OBJECT IDENTIFIER ::= 180
ub-x121-address-length INTEGER {
     iso(1) member-body(2) us(840) ansi-x942(10046) number-type(2) 1 }

DomainParameters ::= 16

-- Note - upper bounds on TeletexString are measured in characters.



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-- A significantly greater number of octets will be required to hold SEQUENCE {
     p       INTEGER, -- such a value.  As a minimum, 16 octets, or twice the specified upper odd prime, p=jq +1
     g       INTEGER, -- bound, whichever is the larger, should be allowed.

END

Appendix B. 1993 ASN.1 Structures and OIDs


PKIX1 DEFINITIONS IMPLICIT TAGS::=

BEGIN generator, g
     q       INTEGER, -- factor of p-1
     j       INTEGER OPTIONAL, -- Proposed PKIX OIDs
id-pkix subgroup factor, j>= 2
     validationParms  ValidationParms OPTIONAL }

ValidationParms ::= SEQUENCE {
     seed             BIT STRING,
     pgenCounter      INTEGER }

id-dsa OBJECT IDENTIFIER ::= {
     iso(1) identified-organization(3) dod(6) internet(1)
                    security(5) mechanisms(5) pkix(7) member-body(2) us(840) x9-57(10040) x9algorithm(4) 1 }

Dss-Parms  ::=  SEQUENCE  {
     p             INTEGER,
     q             INTEGER,
     g             INTEGER  }




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     -- PKIX arcs The ASN.1 in this section supports the Name type
     -- arc for private certificate extensions
id-pe OBJECT IDENTIFIER and the directoryAttribute extension

-- attribute data types --

Attribute       ::=     SEQUENCE { id-pkix 1 }
        type            ATTRIBUTE.&id ({SupportedAttributes}),
        values  SET SIZE (1 .. MAX) OF ATTRIBUTE.&Type
                        ({SupportedAttributes}{@type})}

AttributeTypeAndValue           ::=     SEQUENCE {
        type            ATTRIBUTE.&id ({SupportedAttributes}),
        value   ATTRIBUTE.&Type ({SupportedAttributes}{@type})}

-- arc for policy qualifier naming data types
id-qt OBJECT IDENTIFIER --

Name            ::=     CHOICE { id-pkix 2 } -- arc only one possibility for extended key purpose OIDS
id-kp now --
                                        rdnSequence  RDNSequence }

RDNSequence ::= SEQUENCE OF RelativeDistinguishedName

RelativeDistinguishedName       ::=
                SET SIZE (1 .. MAX) OF AttributeTypeAndValue

ID     ::=    OBJECT IDENTIFIER ::= { id-pkix 3 }

-- arc ATTRIBUTE information object class specification
--  Note: This has been greatly simplified for access descriptors
id-ad PKIX !!

ATTRIBUTE               ::=     CLASS {
        &Type,
        &id                     OBJECT IDENTIFIER ::= UNIQUE }
WITH SYNTAX { id-pkix 48
        WITH SYNTAX &Type ID &id }

-- pkix private extensions
id-pe-authorityInfoAccess OBJECT IDENTIFIER suggested naming attributes
--      Definition of the following information object set may be
--    augmented to meet local requirements.  Note that deleting
--    members of the set may prevent interoperability with
--    conforming implementations.

SupportedAttributes     ATTRIBUTE       ::=     { id-pe 1
              name | commonName | surname | givenName | initials |
              generationQualifier | dnQualifier | countryName |
              localityName | stateOrProvinceName | organizationName |
              organizationalUnitName | title | pkcs9email }

-- policyQualifierIds for Internet policy qualifiers
id-qt-cps      OBJECT IDENTIFIER

name ATTRIBUTE  ::=     { id-qt 1



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        WITH SYNTAX                     DirectoryString { ub-name }
id-qt-unotice  OBJECT IDENTIFIER
        ID                                      id-at-name }

commonName ATTRIBUTE    ::=     { id-qt 2
        WITH SYNTAX                     DirectoryString {ub-common-name}
        ID                                      id-at-commonName }

-- extended key purpose OIDs
id-kp-serverAuth      OBJECT IDENTIFIER

surname ATTRIBUTE       ::=             { id-kp 1
        WITH SYNTAX                     DirectoryString {ub-name}
        ID                                      id-at-surname }
id-kp-clientAuth      OBJECT IDENTIFIER

givenName ATTRIBUTE     ::=             { id-kp 2
        WITH SYNTAX                     DirectoryString {ub-name}
        ID                                      id-at-givenName }
id-kp-codeSigning     OBJECT IDENTIFIER

initials ATTRIBUTE      ::=             { id-kp 3
        WITH SYNTAX                     DirectoryString {ub-name}
        ID                                      id-at-initials }
id-kp-emailProtection OBJECT IDENTIFIER

generationQualifier ATTRIBUTE   ::=             { id-kp 4
        WITH SYNTAX                     DirectoryString {ub-name}
        ID                              id-at-generationQualifier}

dnQualifier ATTRIBUTE   ::=     {
        WITH SYNTAX                     PrintableString
        ID                                      id-at-dnQualifier }
id-kp-ipsecEndSystem  OBJECT IDENTIFIER


countryName ATTRIBUTE   ::=     { id-kp 5
        WITH SYNTAX                     PrintableString (SIZE (2))
                                             -- IS 3166 codes only
        ID                                      id-at-countryName }
id-kp-ipsecTunnel     OBJECT IDENTIFIER

localityName ATTRIBUTE  ::=     { id-kp 6
        WITH SYNTAX             DirectoryString {ub-locality-name}
        ID                      id-at-localityName }
id-kp-ipsecUser       OBJECT IDENTIFIER

stateOrProvinceName ATTRIBUTE   ::=     { id-kp 7
        WITH SYNTAX             DirectoryString {ub-state-name}
        ID                      id-at-stateOrProvinceName }
id-kp-timeStamping    OBJECT IDENTIFIER

organizationName ATTRIBUTE      ::=     { id-kp 8
        WITH SYNTAX             DirectoryString {ub-organization-name}
        ID                      id-at-organizationName }

-- access descriptors for authority info access extension
id-ad-ocsp      OBJECT IDENTIFIER

organizationalUnitName ATTRIBUTE        ::=     { id-ad 1
        WITH SYNTAX  DirectoryString {ub-organizational-unit-name}
        ID                      id-at-organizationalUnitName }



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id-ad-caIssuers


title ATTRIBUTE ::=                     {
        WITH SYNTAX             DirectoryString {ub-title}
        ID                      id-at-title }

 -- Legacy attributes

pkcs9email ATTRIBUTE ::= {
        WITH SYNTAX                     PHGString,
        ID                              emailAddress }

PHGString ::= IA5String (SIZE(1..ub-emailaddress-length))

pkcs-9 OBJECT IDENTIFIER ::=
       { id-ad 2 iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 9 }

emailAddress OBJECT IDENTIFIER ::= { pkcs-9 1 }

    -- object identifiers for Name type and directory attribute data types support

--

Attribute Object identifier assignments --

id-at   OBJECT IDENTIFIER       ::=     SEQUENCE {
        type    AttributeValue,
        values  SET OF AttributeValue     {joint-iso-ccitt(2) ds(5) 4}

-- at least one value is required Attributes -- }

AttributeType

id-at-commonName        OBJECT IDENTIFIER       ::=     {id-at 3}
id-at-surname           OBJECT IDENTIFIER

AttributeValue       ::=     ANY

AttributeTypeAndValue     {id-at 4}
id-at-countryName       OBJECT IDENTIFIER       ::=     SEQUENCE {
        type    AttributeType,
        value   AttributeValue }

AttributeValueAssertion     {id-at 6}
id-at-localityName      OBJECT IDENTIFIER       ::=     {id-at 7}
id-at-stateOrProvinceName     OBJECT IDENTIFIER ::=     {id-at 8}
id-at-organizationName        OBJECT IDENTIFIER ::=     {id-at 10}
id-at-organizationalUnitName  OBJECT IDENTIFIER ::=     {id-at 11}
id-at-title             OBJECT IDENTIFIER       ::=     {id-at 12}
id-at-name              OBJECT IDENTIFIER       ::=     SEQUENCE {AttributeType, AttributeValue}

-- naming data types --

Name     {id-at 41}
id-at-givenName         OBJECT IDENTIFIER       ::=     CHOICE { -- only one possibility for now --
                                        rdnSequence  RDNSequence }

RDNSequence     {id-at 42}
id-at-initials          OBJECT IDENTIFIER       ::=     SEQUENCE OF RelativeDistinguishedName

DistinguishedName     {id-at 43}
id-at-generationQualifier     OBJECT IDENTIFIER ::=     RDNSequence

RelativeDistinguishedName     {id-at 44}
id-at-dnQualifier       OBJECT IDENTIFIER       ::=  SET SIZE (1 .. MAX) OF
                                               AttributeTypeAndValue     {id-at 46}

-- Directory string type type, used extensively in Name types --

DirectoryString { INTEGER:maxSize } ::= CHOICE {
        teletexString           TeletexString (SIZE (1..maxSize)),
        printableString         PrintableString (SIZE (1..maxSize)),
        universalString         UniversalString (SIZE (1..maxSize)),
        bmpString               BMPString (SIZE(1..maxSIZE))
                            }

-- from AuthenticationFramework
--    {joint-iso-ccitt ds(5) modules(1) authenticationFramework(7) 2}
-- note this module was defined with EXPLICIT TAGS

-- types --

Certificate            ::=    EXPLICIT SIGNED {SEQUENCE{
version                 [0]   Version DEFAULT v1,



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serialNumber                  CertificateSerialNumber,
signature                     AlgorithmIdentifier,
issuer                        Name,
validity                      Validity,
subject                       Name,
subjectPublicKeyInfo          SubjectPublicKeyInfo}
issuerUniqueIdentifier  [1]   IMPLICIT UniqueIdentifier OPTIONAL,
                              ---if present, version must be  v1 or v2--
subjectUniqueIdentifier [2]   IMPLICIT UniqueIdentifier OPTIONAL,
                              ---if present, version must be v1 or v2--
extensions              [3]   Extensions Optional
                              --if present, version must be v3--}  }


Version                 ::=   INTEGER {v1(0), v2(1), v3(2) }

CertificateSerialNumber ::=     INTEGER
Algorithmidentifier     ::=     SEQUENCE{
algorithm               ALGORITHM.&id({SupportedAlgorithms}),
parameters              ALGORITHM.&Type({SupportedAlgorithms}
                                           { @algorithm}) OPTIONAL }

--      Definition of the following information object is deferred.
--      SupportedAlgorithms     ALGORITHM  ::=  { ...|... }

Validity                        ::=     SEQUENCE{
notBefore       Time,
notAfter                Time }

Time ::= CHOICE {
        utcTime         UTCTime,
        generalTime             GeneralizedTime }

SubjectPublicKeyInfo    ::=     SEQUENCE{
algorithm                       AlgorithmIdentifier,
subjectPublicKey        BIT STRING}

Extensions        ::=   SEQUENCE SIZE (1..MAX) OF Extension

Extension         ::=   SEQUENCE {
extnId            EXTENSION.&id ({ExtensionSet}),
critical          BOOLEAN DEFAULT FALSE,
extnValue         OCTET STRING
                -- contains a DER encoding of a value of type
                -- &ExtnType for the
                -- extension object identified by extnId --

-- Definition of the following information object set is deferred,               BMPString (SIZE(1..maxSize)),
        utf8String                      UTF8String (SIZE(1..maxSize))
                            }



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     -- End of ASN.1 for Name type and directory attribute support --

     -- The set is required to specify a table constraint on the critical ASN.1 in this section supports X.400 style names   --
     -- for implementations that use the x400Address component --
     -- of Extension. GeneralName.                                        --      ExtensionSet    EXTENSION       ::=     { ... | ... }

EXTENSION       ::=     CLASS
{
&id             OBJECT IDENTIFIER UNIQUE,
&ExtnType
}
WITH SYNTAX
{
SYNTAX          &ExtnType
IDENTIFIED BY   &id
}


CertificateList

ORAddress ::=    EXPLICIT SIGNED { SEQUENCE {
version                Version
   built-in-standard-attributes BuiltInStandardAttributes,
   built-in-domain-defined-attributes
                        BuiltInDomainDefinedAttributes OPTIONAL,
   -- if present, must be v2
signature              AlgorithmIdentifier,
issuer                 Name,
thisUpdate             Time,
nextUpdate             Time OPTIONAL,
revokedCertificates    SEQUENCE OF SEQUENCE {
userCertificate        CertificateSerialNumber,
revocationDate         Time,
crlEntryExtensions     Extensions see also teletex-domain-defined-attributes
   extension-attributes ExtensionAttributes OPTIONAL } OPTIONAL,
crlExtensions          [0]      Extensions OPTIONAL }}

-- information object classes  The OR-address is semantically absent from the OR-name if the
--

ALGORITHM       ::=     TYPE-IDENTIFIER  built-in-standard-attribute sequence is empty and the
-- Parameterized Types  built-in-domain-defined-attributes and extension-attributes are
--  both omitted.

--
HASHED {ToBeHashed}      Built-in Standard Attributes

BuiltInStandardAttributes ::=     OCTET STRING ( CONSTRAINED-BY SEQUENCE {
    --must be the result of applying a hashing procedure to the
   country-name CountryName OPTIONAL,
   administration-domain-name AdministrationDomainName OPTIONAL,
   network-address      [0] NetworkAddress OPTIONAL,
   --
    --DER-encoded octets of a value of see also extended-network-address
   terminal-identifier  [1] TerminalIdentifier OPTIONAL,
   private-domain-name  [2] PrivateDomainName OPTIONAL,
   organization-name    [3] OrganizationName OPTIONAL,
   -- ToBeHashed })

ENCRYPTED { ToBeEnciphered}     :=      BIT STRING ( CONSTRAINED BY {
    --must be the result of applying an encipherment procedure to the see also teletex-organization-name
   numeric-user-identifier      [4] NumericUserIdentifier OPTIONAL,
   personal-name        [5] PersonalName OPTIONAL,
   --
    --BER-encoded octets of a value of see also teletex-personal-name
   organizational-unit-names    [6] OrganizationalUnitNames OPTIONAL
   -- see also teletex-organizational-unit-names -- ToBeEnciphered })

SIGNED { ToBeSigned }

CountryName ::=     SEQUENCE{
        ToBeSigned,
        COMPONENTS OF SIGNATURE { ToBeSigned }),

SIGNATURE [APPLICATION 1] CHOICE { OfSignature
   x121-dcc-code NumericString
                (SIZE (ub-country-name-numeric-length)),
   iso-3166-alpha2-code PrintableString
                (SIZE (ub-country-name-alpha-length)) }

AdministrationDomainName ::=     SEQUENCE [APPLICATION 2] CHOICE {
        AlgorithmIdentifier,
   numeric NumericString (SIZE (0..ub-domain-name-length)),
   printable PrintableString (SIZE (0..ub-domain-name-length)) }

NetworkAddress ::= X121Address
-- see also extended-network-address




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        ENCRYPTED { HASHED { OfSignature }}}

-- Key and policy information extensions --

authorityKeyIdentifier EXTENSION ::= {
        SYNTAX          AuthorityKeyIdentifier
        IDENTIFIED BY   { id-ce 35 } }

AuthorityKeyIdentifier ::= SEQUENCE {
    keyIdentifier               [0] KeyIdentifier            OPTIONAL,
    authorityCertIssuer         [1] GeneralNames             OPTIONAL,
    authorityCertSerialNumber   [2] CertificateSerialNumber  OPTIONAL }
        ( WITH COMPONENTS       {..., authorityCertIssuer PRESENT,
                                authorityCertSerialNumber PRESENT} |
         WITH COMPONENTS        {..., authorityCertIssuer ABSENT,
                                authorityCertSerialNumber ABSENT} )

KeyIdentifier ::= OCTET STRING

subjectKeyIdentifier EXTENSION


X121Address ::= {
        SYNTAX          SubjectKeyIdentifier
        IDENTIFIED BY   { id-ce 14 } }

SubjectKeyIdentifier NumericString (SIZE (1..ub-x121-address-length))

TerminalIdentifier ::= KeyIdentifier

keyUsage EXTENSION PrintableString (SIZE (1..ub-terminal-id-length))

PrivateDomainName ::= CHOICE {
        SYNTAX  KeyUsage
        IDENTIFIED BY { id-ce 15 }
   numeric NumericString (SIZE (1..ub-domain-name-length)),
   printable PrintableString (SIZE (1..ub-domain-name-length)) }

KeyUsage

OrganizationName ::= BIT STRING {
        digitalSignature     (0),
        nonRepudiation       (1),
        keyEncipherment      (2),
        dataEncipherment     (3),
        keyAgreement         (4),
        keyCertSign          (5),
        cRLSign              (6) }

privateKeyUsagePeriod EXTENSION PrintableString
                           (SIZE (1..ub-organization-name-length))
-- see also teletex-organization-name

NumericUserIdentifier ::= {
        SYNTAX  PrivateKeyUsagePeriod
        IDENTIFIED BY { id-ce 16 } }

PrivateKeyUsagePeriod NumericString
                             (SIZE (1..ub-numeric-user-id-length))

PersonalName ::= SEQUENCE SET {
        notBefore
   surname    [0]     GeneralizedTime OPTIONAL,
        notAfter PrintableString (SIZE (1..ub-surname-length)),
   given-name [1]     GeneralizedTime OPTIONAL }
        ( WITH COMPONENTS       {..., notBefore PRESENT} |
        WITH COMPONENTS         {..., notAfter PRESENT} )




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certificatePolicies EXTENSION PrintableString
                        (SIZE (1..ub-given-name-length)) OPTIONAL,
   initials   [2] PrintableString
                        (SIZE (1..ub-initials-length)) OPTIONAL,
   generation-qualifier [3] PrintableString
                (SIZE (1..ub-generation-qualifier-length)) OPTIONAL}
-- see also teletex-personal-name

OrganizationalUnitNames ::= {
        SYNTAX  CertificatePoliciesSyntax
        IDENTIFIED BY { id-ce 32 } }

CertificatePoliciesSyntax SEQUENCE SIZE (1..ub-organizational-units)
                                        OF OrganizationalUnitName
-- see also teletex-organizational-unit-names

OrganizationalUnitName ::= PrintableString (SIZE
                        (1..ub-organizational-unit-name-length))

--      Built-in Domain-defined Attributes
BuiltInDomainDefinedAttributes ::= SEQUENCE SIZE (1..MAX)
                                (1..ub-domain-defined-attributes) OF PolicyInformation

PolicyInformation
                                BuiltInDomainDefinedAttribute

BuiltInDomainDefinedAttribute ::= SEQUENCE {
        policyIdentifier   CertPolicyId,
        policyQualifiers   SEQUENCE SIZE (1..MAX) OF
                PolicyQualifierInfo OPTIONAL
   type PrintableString (SIZE
                (1..ub-domain-defined-attribute-type-length)),
   value PrintableString (SIZE
                (1..ub-domain-defined-attribute-value-length)) }

CertPolicyId

--      Extension Attributes

ExtensionAttributes ::= OBJECT IDENTIFIER

PolicyQualifierInfo SET SIZE (1..ub-extension-attributes)
                                        OF ExtensionAttribute
ExtensionAttribute ::= SEQUENCE {
        policyQualifierId       CERT-POLICY-QUALIFIER.&id
                                    ({SupportedPolicyQualifiers}),
        qualifier               CERT-POLICY-QUALIFIER.&Qualifier
                                    ({SupportedPolicyQualifiers}
                                    {@policyQualifierId})OPTIONAL }

SupportedPolicyQualifiers CERT-POLICY-QUALIFIER ::= { ...



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        extension-attribute-type [0] EXTENSION-ATTRIBUTE.&id
                                        ({ExtensionAttributeTable}),
        extension-attribute-value [1] EXTENSION-ATTRIBUTE.&Type
             ({ExtensionAttributeTable} {@extension-attribute-type}) }

CERT-POLICY-QUALIFIER

EXTENSION-ATTRIBUTE ::= CLASS {
        &id             OBJECT IDENTIFIER     INTEGER (0..ub-extension-attributes) UNIQUE,
        &Qualifier      OPTIONAL
        &Type }
WITH SYNTAX {&Type IDENTIFIED BY &id}

ExtensionAttributeTable EXTENSION-ATTRIBUTE ::= {
        POLICY-QUALIFIER-ID     &id
        [QUALIFIER-TYPE &Qualifier]
        common-name |
        teletex-common-name |
        teletex-organization-name |
        teletex-personal-name |
        teletex-organizational-unit-names |
        teletex-domain-defined-attributes |
        pds-name |
        physical-delivery-country-name |
        postal-code |
        physical-delivery-office-name |
        physical-delivery-office-number |
        extension-OR-address-components |
        physical-delivery-personal-name |
        physical-delivery-organization-name |
        extension-physical-delivery-address-components |
        unformatted-postal-address |
        street-address |
        post-office-box-address |
        poste-restante-address |
        unique-postal-name |
        local-postal-attributes |
        extended-network-address |
        terminal-type }

policyMappings EXTENSION

--      Extension Standard Attributes

common-name EXTENSION-ATTRIBUTE ::= {
        SYNTAX  PolicyMappingsSyntax {CommonName IDENTIFIED BY { id-ce 33 } }

PolicyMappingsSyntax 1}

CommonName ::= SEQUENCE SIZE (1..MAX) OF SEQUENCE {
        issuerDomainPolicy           CertPolicyId,
        subjectDomainPolicy          CertPolicyId }

supportedAlgorithms ATTRIBUTE PrintableString (SIZE (1..ub-common-name-length))

teletex-common-name EXTENSION-ATTRIBUTE ::= {
        WITH SYNTAX SupportedAlgorithm
        EQUALITY MATCHING RULE algorithmIdentifierMatch
        ID { id-at 52 } }

SupportedAlgorithm
                {TeletexCommonName IDENTIFIED BY 2}

TeletexCommonName ::= SEQUENCE {
   algorithmIdentifier         AlgorithmIdentifier,
   intendedUsage               [0]  KeyUsage OPTIONAL,
   intendedCertificatePolicies [1]  CertificatePoliciesSyntax OPTIONAL } TeletexString (SIZE (1..ub-common-name-length))

teletex-organization-name EXTENSION-ATTRIBUTE ::=
                {TeletexOrganizationName IDENTIFIED BY 3}



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-- Certificate subject and certificate issuer attributes extensions --

subjectAltName EXTENSION


TeletexOrganizationName ::= {
        SYNTAX  GeneralNames
                TeletexString (SIZE (1..ub-organization-name-length))

teletex-personal-name EXTENSION-ATTRIBUTE ::=
                {TeletexPersonalName IDENTIFIED BY { id-ce 17 } }

GeneralNames ::= SEQUENCE SIZE (1..MAX) OF GeneralName

GeneralName 4}

TeletexPersonalName ::= CHOICE SET {
        otherName
   surname [0] INSTANCE OF OTHER-NAME,
        rfc822Name TeletexString (SIZE (1..ub-surname-length)),
   given-name [1] IA5String,
        dNSName TeletexString
                (SIZE (1..ub-given-name-length)) OPTIONAL,
   initials [2] IA5String,
        x400Address TeletexString (SIZE (1..ub-initials-length)) OPTIONAL,
   generation-qualifier [3] ORAddress,
        directoryName               [4] Name,
        ediPartyName                [5] EDIPartyName,
        uniformResourceIdentifier   [6] IA5String,
        iPAddress                   [7] OCTET STRING,
        registeredID                [8] OBJECT IDENTIFIER TeletexString (SIZE
                (1..ub-generation-qualifier-length)) OPTIONAL }

OTHER-NAME

teletex-organizational-unit-names EXTENSION-ATTRIBUTE ::= TYPE-IDENTIFIER

EDIPartyName
   {TeletexOrganizationalUnitNames IDENTIFIED BY 5}

TeletexOrganizationalUnitNames ::= SEQUENCE {
        nameAssigner        [0] DirectoryString {ub-name} OPTIONAL,
        partyName           [1] DirectoryString {ub-name} }

issuerAltName EXTENSION SIZE
        (1..ub-organizational-units) OF TeletexOrganizationalUnitName

TeletexOrganizationalUnitName ::= {
        SYNTAX  GeneralNames TeletexString
                        (SIZE (1..ub-organizational-unit-name-length))

pds-name EXTENSION-ATTRIBUTE ::= {PDSName IDENTIFIED BY { id-ce 18 } }

subjectDirectoryAttributes EXTENSION 7}

PDSName ::= {
        SYNTAX  AttributesSyntax PrintableString (SIZE (1..ub-pds-name-length))

physical-delivery-country-name EXTENSION-ATTRIBUTE ::=
   {PhysicalDeliveryCountryName IDENTIFIED BY 8}

PhysicalDeliveryCountryName ::= CHOICE { id-ce 9 }
   x121-dcc-code NumericString (SIZE (ub-country-name-numeric-length)),
   iso-3166-alpha2-code PrintableString
                        (SIZE (ub-country-name-alpha-length)) }

AttributesSyntax ::= SEQUENCE SIZE (1..MAX) OF Attribute


-- Certification path constraints extensions --

basicConstraints EXTENSION

postal-code EXTENSION-ATTRIBUTE ::= {
        SYNTAX  BasicConstraintsSyntax {PostalCode IDENTIFIED BY { id-ce 19 } }

BasicConstraintsSyntax 9}

PostalCode ::= SEQUENCE CHOICE {
        cA                      BOOLEAN DEFAULT FALSE,
        pathLenConstraint       INTEGER (0..MAX) OPTIONAL
   numeric-code NumericString (SIZE (1..ub-postal-code-length)),
   printable-code PrintableString (SIZE (1..ub-postal-code-length)) }

nameConstraints EXTENSION

physical-delivery-office-name EXTENSION-ATTRIBUTE ::= {
        SYNTAX  NameConstraintsSyntax
                        {PhysicalDeliveryOfficeName IDENTIFIED BY 10}

PhysicalDeliveryOfficeName ::= PDSParameter

physical-delivery-office-number EXTENSION-ATTRIBUTE ::=
   {PhysicalDeliveryOfficeNumber IDENTIFIED BY 11}



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PhysicalDeliveryOfficeNumber ::= PDSParameter

extension-OR-address-components EXTENSION-ATTRIBUTE ::=
   {ExtensionORAddressComponents IDENTIFIED BY { id-ce 30 } }

NameConstraintsSyntax 12}

ExtensionORAddressComponents ::= SEQUENCE {
        permittedSubtrees       [0]     GeneralSubtrees OPTIONAL,
        excludedSubtrees        [1]     GeneralSubtrees OPTIONAL }

GeneralSubtrees PDSParameter

physical-delivery-personal-name EXTENSION-ATTRIBUTE ::= SEQUENCE SIZE (1..MAX) OF GeneralSubtree

GeneralSubtree
   {PhysicalDeliveryPersonalName IDENTIFIED BY 13}

PhysicalDeliveryPersonalName ::= SEQUENCE {
        base                    GeneralName,
        minimum         [0]     BaseDistance DEFAULT 0,
        maximum         [1]     BaseDistance OPTIONAL }

BaseDistance PDSParameter

physical-delivery-organization-name EXTENSION-ATTRIBUTE ::=
   {PhysicalDeliveryOrganizationName IDENTIFIED BY 14}

PhysicalDeliveryOrganizationName ::= INTEGER (0..MAX)

policyConstraints EXTENSION PDSParameter

extension-physical-delivery-address-components EXTENSION-ATTRIBUTE ::= {
        SYNTAX  PolicyConstraintsSyntax
   {ExtensionPhysicalDeliveryAddressComponents IDENTIFIED BY { id-ce 36 } }

PolicyConstraints Syntax 15}

ExtensionPhysicalDeliveryAddressComponents ::= PDSParameter

unformatted-postal-address EXTENSION-ATTRIBUTE ::=
                        {UnformattedPostalAddress IDENTIFIED BY 16}

UnformattedPostalAddress ::= SET {
   printable-address SEQUENCE SIZE (1..MAX) (1..ub-pds-physical-address-lines) OF SEQUENCE {
        requireExplicitPolicy   [0] SkipCerts
           PrintableString (SIZE (1..ub-pds-parameter-length)) OPTIONAL,
        inhibitPolicyMapping    [1] SkipCerts
   teletex-string TeletexString (SIZE
                         (1..ub-unformatted-address-length)) OPTIONAL }

SkipCerts

street-address EXTENSION-ATTRIBUTE ::= INTEGER (0..MAX)

-- Basic CRL extensions --

cRLNumber EXTENSION
                {StreetAddress IDENTIFIED BY 17}

StreetAddress ::= {
        SYNTAX  CRLNumber PDSParameter

post-office-box-address EXTENSION-ATTRIBUTE ::=
                {PostOfficeBoxAddress IDENTIFIED BY { id-ce 20 } }

CRLNumber 18}

PostOfficeBoxAddress ::= INTEGER (0..MAX)

reasonCode EXTENSION PDSParameter

poste-restante-address EXTENSION-ATTRIBUTE ::= {
        SYNTAX  CRLReason
                {PosteRestanteAddress IDENTIFIED BY { id-ce 21 } }

CRLReason 19}

PosteRestanteAddress ::= ENUMERATED {
        unspecified                     (0),
        keyCompromise           (1),
        cACompromise            (2),
        affiliationChanged              (3),
        superseded                      (4),
        cessationOfOperation            (5),
        certificateHold                 (6),
        removeFromCRL           (8) }

instructionCode EXTENSION PDSParameter

unique-postal-name EXTENSION-ATTRIBUTE ::= {
                {UniquePostalName IDENTIFIED BY 20}



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        SYNTAX  HoldInstruction
        IDENTIFIED BY { id-ce 23 } }

HoldInstruction


UniquePostalName ::= OBJECT IDENTIFIER

invalidityDate EXTENSION PDSParameter

local-postal-attributes EXTENSION-ATTRIBUTE ::= {
        SYNTAX  GeneralizedTime
                {LocalPostalAttributes IDENTIFIED BY 21}

LocalPostalAttributes ::= PDSParameter

PDSParameter ::= SET { id-ce 24 }
   printable-string PrintableString
            (SIZE(1..ub-pds-parameter-length)) OPTIONAL,
   teletex-string TeletexString
            (SIZE(1..ub-pds-parameter-length)) OPTIONAL }


-- CRL distribution points and delta-CRL extensions --

cRLDistributionPoints EXTENSION

extended-network-address EXTENSION-ATTRIBUTE ::= {
        SYNTAX  CRLDistPointsSyntax
                {ExtendedNetworkAddress IDENTIFIED BY   { id-ce 31 } }

CRLDistPointsSyntax 22}

ExtendedNetworkAddress ::= CHOICE {
        e163-4-address SEQUENCE SIZE (1..MAX) OF DistributionPoint

DistributionPoint {
                number [0] NumericString
                   (SIZE (1..ub-e163-4-number-length)),
                sub-address [1] NumericString
                   (SIZE (1..ub-e163-4-sub-address-length)) OPTIONAL},
        psap-address [0] PresentationAddress }

PresentationAddress ::= SEQUENCE {
        distributionPoint
        pSelector       [0]     DistributionPointName EXPLICIT OCTET STRING OPTIONAL,
        reasons
        sSelector       [1]     ReasonFlags EXPLICIT OCTET STRING OPTIONAL,
        cRLIssuer
        tSelector       [2]     GeneralNames OPTIONAL }

DistributionPointName EXPLICIT OCTET STRING OPTIONAL,
        nAddresses      [3] EXPLICIT SET SIZE (1..MAX) OF OCTET STRING}


terminal-type EXTENSION-ATTRIBUTE ::= CHOICE {
        fullName                [0]     GeneralNames,
        nameRelativeToCRLIssuer [1]     RelativeDistinguishedName }

ReasonFlags {TerminalType IDENTIFIED BY 23}

TerminalType ::= BIT STRING INTEGER {
        unused                  (0),
        keyCompromise           (1),
        caCompromise            (2),
        affiliationChanged
   telex (3),
        superseded
   teletex (4),
        cessationOfOperation
   g3-facsimile (5),
        certificateHold         (6)
   g4-facsimile (6),
   ia5-terminal (7),
   videotex (8) }

issuingDistributionPoint EXTENSION (0..ub-integer-options)

--      Extension Domain-defined Attributes

teletex-domain-defined-attributes EXTENSION-ATTRIBUTE ::= {
        SYNTAX  IssuingDistPointSyntax
   {TeletexDomainDefinedAttributes IDENTIFIED BY   { id-ce 28 } }

IssuingDistPointSyntax 6}

TeletexDomainDefinedAttributes ::= SEQUENCE {
        distributionPoint       [0] DistributionPointName OPTIONAL,
        onlyContainsUserCerts   [1] BOOLEAN DEFAULT FALSE,
        onlyContainsCACerts     [2] BOOLEAN DEFAULT FALSE,
        onlySomeReasons         [3] ReasonFlags OPTIONAL,
        indirectCRL             [4] BOOLEAN DEFAULT FALSE }

certificateIssuer EXTENSION ::= { SIZE
   (1..ub-domain-defined-attributes) OF TeletexDomainDefinedAttribute



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        SYNTAX          GeneralNames
        IDENTIFIED BY           { id-ce 29 } }

deltaCRLIndicator EXTENSION ::= {
        SYNTAX          BaseCRLNumber
        IDENTIFIED BY   { id-ce 27 } }

BaseCRLNumber ::= CRLNumber

deltaRevocationList ATTRIBUTE


TeletexDomainDefinedAttribute ::= SEQUENCE {
        WITH SYNTAX     CertificateList
        EQUALITY MATCHING RULE certificateListExactMatch
        ID      {id-at 53 }
    type TeletexString
         (SIZE (1..ub-domain-defined-attribute-type-length)),
    value TeletexString
         (SIZE (1..ub-domain-defined-attribute-value-length)) }

-- Object identifier assignments  specifications of Upper Bounds
--

id-ce-subjectDirectoryAttributes OBJECT IDENTIFIER  must be regarded as mandatory
--  from Annex B of ITU-T X.411
--  Reference Definition of MTS Parameter Upper Bounds

--      Upper Bounds
ub-name INTEGER ::= {id-ce 9}
id-ce-subjectKeyIdentifier       OBJECT IDENTIFIER     32768
ub-common-name  INTEGER ::= {id-ce 14}
id-ce-keyUsage          OBJECT IDENTIFIER     64
ub-locality-name        INTEGER ::=     {id-ce 15}
id-ce-privateKeyUsagePeriod     OBJECT IDENTIFIER     128
ub-state-name   INTEGER ::=  {id-ce 16}
id-ce-subjectAltName    OBJECT IDENTIFIER     128
ub-organization-name    INTEGER ::=     {id-ce 17}
id-ce-issuerAltName     OBJECT IDENTIFIER     64
ub-organizational-unit-name     INTEGER ::=     {id-ce 18}
id-ce-basicConstraints  OBJECT IDENTIFIER     64
ub-title        INTEGER ::=     64
ub-match        INTEGER ::=     128

ub-emailaddress-length INTEGER ::= 128

ub-common-name-length INTEGER ::= 64
ub-country-name-alpha-length INTEGER ::= 2
ub-country-name-numeric-length INTEGER ::= 3
ub-domain-defined-attributes INTEGER ::= 4
ub-domain-defined-attribute-type-length INTEGER ::= 8
ub-domain-defined-attribute-value-length INTEGER ::= 128
ub-domain-name-length INTEGER ::= 16
ub-extension-attributes INTEGER ::= 256
ub-e163-4-number-length INTEGER ::=     {id-ce 19}
id-ce-cRLNumber         OBJECT IDENTIFIER 15
ub-e163-4-sub-address-length INTEGER ::=     {id-ce 20}
id-ce-reasonCode        OBJECT IDENTIFIER 40
ub-generation-qualifier-length INTEGER ::=     {id-ce 21}
id-ce-instructionCode   OBJECT IDENTIFIER 3
ub-given-name-length INTEGER ::=     {id-ce 23}
id-ce-invalidityDate    OBJECT IDENTIFIER 16
ub-initials-length INTEGER ::=     {id-ce 24}
id-ce-deltaCRLIndicator OBJECT IDENTIFIER 5
ub-integer-options INTEGER ::=     {id-ce 27}
id-ce-issuingDistributionPoint  OBJECT IDENTIFIER 256
ub-numeric-user-id-length INTEGER ::=  {id-ce 28}
id-ce-certificateIssuer OBJECT IDENTIFIER 32
ub-organization-name-length INTEGER ::=     {id-ce 29}
id-ce-nameConstraints   OBJECT IDENTIFIER 64
ub-organizational-unit-name-length INTEGER ::=     {id-ce 30}
id-ce-cRLDistributionPoints     OBJECT IDENTIFIER 32
ub-organizational-units INTEGER ::=  {id-ce 31}
id-ce-certificatePolicies       OBJECT IDENTIFIER 4
ub-pds-name-length INTEGER ::=  {id-ce 32}
id-ce-policyMappings    OBJECT IDENTIFIER 16
ub-pds-parameter-length INTEGER ::=     {id-ce 33}
id-ce-policyConstraints OBJECT IDENTIFIER 30
ub-pds-physical-address-lines INTEGER ::=     {id-ce 36}
id-ce-authorityKeyIdentifier    OBJECT IDENTIFIER 6
ub-postal-code-length INTEGER ::=  {id-ce 35}

-- PKIX 1 extensions

id-pe-authorityInfoAccess OBJECT IDENTIFIER 16
ub-surname-length INTEGER ::= { id-pe 1 }

AuthorityInfoAccessSyntax 40
ub-terminal-id-length INTEGER ::=
        SEQUENCE SIZE (1..MAX) OF AccessDescription

AccessDescription 24
ub-unformatted-address-length INTEGER ::=  SEQUENCE {
        accessMethod          OBJECT IDENTIFIER,
        accessLocation        GeneralName  } 180



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CPSuri


ub-x121-address-length INTEGER ::= IA5String

UserNotice 16

-- Note - upper bounds on TeletexString are measured in characters.
-- A significantly greater number of octets will be required to hold
-- such a value.  As a minimum, 16 octets, or twice the specified upper
-- bound, whichever is the larger, should be allowed.

END











































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B.2 1993 Implicitly Tagged Module


PKIX1Implicit93  {iso(1) identified-organization(3) dod(6) internet(1)
   security(5) mechanisms(5) pkix(7) id-mod(0) id-pkix1-implicit-93(4)}

DEFINITIONS IMPLICIT TAGS::=

BEGIN

--EXPORTS ALL --

IMPORTS
        id-pe, id-qt, id-kp, id-ad, id-qt-unotice,
            ORAddress, Name, RelativeDistinguishedName,
            CertificateSerialNumber, CertificateList,
            AlgorithmIdentifier, ub-name, DirectoryString, Attribute,
            EXTENSION
            FROM PKIX1Explicit93 {iso(1) identified-organization(3)
            dod(6) internet(1) security(5) mechanisms(5) pkix(7)
            id-mod(0) id-pkix1-explicit-93(3)};

-- Key and policy information extensions --

authorityKeyIdentifier EXTENSION ::= CHOICE {
  visibleString     VisibleString,
  bmpString         BMPString
        SYNTAX          AuthorityKeyIdentifier
        IDENTIFIED BY   id-ce-authorityKeyIdentifier }

-- misc missing ASN.1

PresentationAddress

AuthorityKeyIdentifier ::= SEQUENCE {
        pSelector
    keyIdentifier               [0] EXPLICIT OCTET STRING KeyIdentifier            OPTIONAL,
        sSelector
    authorityCertIssuer         [1] EXPLICIT OCTET STRING GeneralNames             OPTIONAL,
        tSelector
    authorityCertSerialNumber   [2] EXPLICIT CertificateSerialNumber  OPTIONAL }
        ( WITH COMPONENTS       {..., authorityCertIssuer PRESENT,
                                authorityCertSerialNumber PRESENT} |
         WITH COMPONENTS        {..., authorityCertIssuer ABSENT,
                                authorityCertSerialNumber ABSENT} )

KeyIdentifier ::= OCTET STRING OPTIONAL,
        nAddresses      [3] EXPLICIT SET SIZE (1..MAX) OF OCTET STRING}


-- The following OBJECT IDENTIFIERS are not used by this specification:
-- {id-ce 2}, {id-ce 3}, {id-ce 4}, {id-ce 5}, {id-ce 6}, {id-ce 7},
-- {id-ce 8}, {id-ce 10}, {id-ce 11}, {id-ce 12}, {id-ce 13},
-- {id-ce 22}, {id-ce 25}, {id-ce 26}

-- X.400, Algorithm Identifier, and maximum values Module

ORAddressAndOrDirectoryName ::= ORName

ORAddressAndOptionalDirectoryName ::= ORName

ORName

subjectKeyIdentifier EXTENSION ::= [APPLICATION 0] SEQUENCE {
   -- address -- COMPONENTS OF ORAddress,
   directory-name [0] Name OPTIONAL
        SYNTAX          SubjectKeyIdentifier
        IDENTIFIED BY   id-ce-subjectKeyIdentifier }

ORAddress

SubjectKeyIdentifier ::= SEQUENCE {
   built-in-standard-attributes BuiltInStandardAttributes,
   built-in-domain-defined-attributes
                        BuiltInDomainDefinedAttributes OPTIONAL,
   -- see also teletex-domain-defined-attributes
   extension-attributes ExtensionAttributes OPTIONAL }

--  The OR-address is semantically absent from the OR-name if the
--  built-in-standard-attribute sequence is empty and the
--  built-in-domain-defined-attributes and extension-attributes are
--  both omitted.

--      Built-in Standard Attributes

BuiltInStandardAttributes KeyIdentifier

keyUsage EXTENSION ::= SEQUENCE {
   country-name CountryName OPTIONAL,
   administration-domain-name AdministrationDomainName OPTIONAL,
        SYNTAX  KeyUsage
        IDENTIFIED BY id-ce-keyUsage }



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   network-address      [0] NetworkAddress OPTIONAL,
   -- see also extended-network-address
   terminal-identifier  [1] TerminalIdentifier OPTIONAL,
   private-domain-name  [2] PrivateDomainName OPTIONAL,
   organization-name    [3] OrganizationName OPTIONAL,
   -- see also teletex-organization-name
   numeric-user-identifier      [4] NumericUserIdentifier OPTIONAL,
   personal-name        [5] PersonalName OPTIONAL,
   -- see also teletex-personal-name
   organizational-unit-names    [6] OrganizationalUnitNames OPTIONAL
   -- see also teletex-organizational-unit-names


KeyUsage ::= BIT STRING {
        digitalSignature     (0),
        nonRepudiation       (1),
        keyEncipherment      (2),
        dataEncipherment     (3),
        keyAgreement         (4),
        keyCertSign          (5),
        cRLSign              (6) }

extendedKeyUsage EXTENSION ::= {
        SYNTAX SEQUENCE SIZE (1..MAX) OF KeyPurposeId
        IDENTIFIED BY id-ce-extKeyUsage }

KeyPurposeId ::= OBJECT IDENTIFIER

-- PKIX-defined extended key purpose OIDs
id-kp-serverAuth      OBJECT IDENTIFIER ::= { id-kp 1 }

CountryName
id-kp-clientAuth      OBJECT IDENTIFIER ::= [APPLICATION 1] CHOICE {
   x121-dcc-code NumericString
                (SIZE (ub-country-name-numeric-length)),
   iso-3166-alpha2-code PrintableString
                (SIZE (ub-country-name-alpha-length)) id-kp 2 }

AdministrationDomainName
id-kp-codeSigning     OBJECT IDENTIFIER ::= [APPLICATION 2] CHOICE {
   numeric NumericString (SIZE (0..ub-domain-name-length)),
   printable PrintableString (SIZE (0..ub-domain-name-length)) id-kp 3 }

NetworkAddress
id-kp-emailProtection OBJECT IDENTIFIER ::= X121Address
-- see also extended-network-address

X121Address { id-kp 4 }
id-kp-ipsecEndSystem  OBJECT IDENTIFIER ::= NumericString (SIZE (1..ub-x121-address-length))

TerminalIdentifier { id-kp 5 }
id-kp-ipsecTunnel     OBJECT IDENTIFIER ::= PrintableString (SIZE (1..ub-terminal-id-length))

PrivateDomainName { id-kp 6 }
id-kp-ipsecUser       OBJECT IDENTIFIER ::= CHOICE {
   numeric NumericString (SIZE (1..ub-domain-name-length)),
   printable PrintableString (SIZE (1..ub-domain-name-length)) id-kp 7 }

OrganizationName
id-kp-timeStamping    OBJECT IDENTIFIER ::= PrintableString
                           (SIZE (1..ub-organization-name-length))
-- see also teletex-organization-name

NumericUserIdentifier { id-kp 8 }

privateKeyUsagePeriod EXTENSION ::= NumericString
                             (SIZE (1..ub-numeric-user-id-length))

PersonalName {
        SYNTAX  PrivateKeyUsagePeriod
        IDENTIFIED BY { id-ce-privateKeyUsagePeriod } }

PrivateKeyUsagePeriod ::= SET SEQUENCE {
   surname
        notBefore       [0] PrintableString (SIZE (1..ub-surname-length)),
   given-name [1] PrintableString
                        (SIZE (1..ub-given-name-length)) OPTIONAL,
   initials   [2] PrintableString
                        (SIZE (1..ub-initials-length))     GeneralizedTime OPTIONAL,
   generation-qualifier [3] PrintableString
                (SIZE (1..ub-generation-qualifier-length)) OPTIONAL}
        notAfter        [1]     GeneralizedTime OPTIONAL }
        ( WITH COMPONENTS       {..., notBefore PRESENT} |
        WITH COMPONENTS         {..., notAfter PRESENT} )

certificatePolicies EXTENSION ::= {
        SYNTAX  CertificatePoliciesSyntax
        IDENTIFIED BY id-ce-certificatePolicies }

CertificatePoliciesSyntax ::=
                SEQUENCE SIZE (1..MAX) OF PolicyInformation

PolicyInformation ::= SEQUENCE {
        policyIdentifier   CertPolicyId,
        policyQualifiers   SEQUENCE SIZE (1..MAX) OF
                PolicyQualifierInfo OPTIONAL }

CertPolicyId ::= OBJECT IDENTIFIER



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-- see also teletex-personal-name

OrganizationalUnitNames


PolicyQualifierInfo ::= SEQUENCE SIZE (1..ub-organizational-units)
                                        OF OrganizationalUnitName
-- see also teletex-organizational-unit-names

OrganizationalUnitName {
        policyQualifierId       CERT-POLICY-QUALIFIER.&id
                                    ({SupportedPolicyQualifiers}),
        qualifier               CERT-POLICY-QUALIFIER.&Qualifier
                                    ({SupportedPolicyQualifiers}
                                    {@policyQualifierId})OPTIONAL }

SupportedPolicyQualifiers CERT-POLICY-QUALIFIER ::= { noticeToUser |
                                                      pointerToCPS }

CERT-POLICY-QUALIFIER ::= CLASS {
        &id             OBJECT IDENTIFIER UNIQUE,
        &Qualifier      OPTIONAL }
WITH SYNTAX {
        POLICY-QUALIFIER-ID     &id
        [QUALIFIER-TYPE &Qualifier] }

policyMappings EXTENSION ::= PrintableString (SIZE
                        (1..ub-organizational-unit-name-length))

--      Built-in Domain-defined Attributes
BuiltInDomainDefinedAttributes {
        SYNTAX  PolicyMappingsSyntax
        IDENTIFIED BY id-ce-policyMappings }

PolicyMappingsSyntax ::= SEQUENCE SIZE
                                (1..ub-domain-defined-attributes) (1..MAX) OF
                                BuiltInDomainDefinedAttribute

BuiltInDomainDefinedAttribute ::= SEQUENCE {
   type PrintableString (SIZE
                (1..ub-domain-defined-attribute-type-length)),
   value PrintableString (SIZE
                (1..ub-domain-defined-attribute-value-length))
        issuerDomainPolicy           CertPolicyId,
        subjectDomainPolicy          CertPolicyId }

--      Extension Attributes

ExtensionAttributes Certificate subject and certificate issuer attributes extensions --

subjectAltName EXTENSION ::= SET {
        SYNTAX  GeneralNames
        IDENTIFIED BY id-ce-subjectAltName }

GeneralNames ::= SEQUENCE SIZE (1..ub-extension-attributes) (1..MAX) OF ExtensionAttribute
ExtensionAttribute GeneralName

GeneralName ::= SEQUENCE CHOICE {
        extension-attribute-type
        otherName                   [0] EXTENSION-ATTRIBUTE.&id
                                        ({ExtensionAttributeTable}),
        extension-attribute-value INSTANCE OF OTHER-NAME,
        rfc822Name                  [1] EXTENSION-ATTRIBUTE.&Type
             ({ExtensionAttributeTable} {@extension-attribute-type}) IA5String,
        dNSName                     [2] IA5String,
        x400Address                 [3] ORAddress,
        directoryName               [4] Name,
        ediPartyName                [5] EDIPartyName,
        uniformResourceIdentifier   [6] IA5String,
        iPAddress                   [7] OCTET STRING,
        registeredID                [8] OBJECT IDENTIFIER }

EXTENSION-ATTRIBUTE

OTHER-NAME ::= CLASS {
        &id     INTEGER (0..ub-extension-attributes) UNIQUE,
        &Type }
WITH SYNTAX {&Type IDENTIFIED BY &id}

ExtensionAttributeTable EXTENSION-ATTRIBUTE TYPE-IDENTIFIER

EDIPartyName ::= SEQUENCE {
        common-name |
        teletex-common-name |
        teletex-organization-name |
        teletex-personal-name |
        teletex-organizational-unit-names |
        teletex-domain-defined-attributes |
        pds-name |
        physical-delivery-country-name |
        postal-code |
        physical-delivery-office-name |
        physical-delivery-office-number |
        extension-OR-address-components |
        nameAssigner        [0] DirectoryString {ub-name} OPTIONAL,



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        physical-delivery-personal-name |
        physical-delivery-organization-name |
        extension-physical-delivery-address-components |
        unformatted-postal-address |
        street-address |
        post-office-box-address |
        poste-restante-address |
        unique-postal-name |
        local-postal-attributes |
        extended-network-address |
        terminal-type


        partyName           [1] DirectoryString {ub-name} }

--      Extension Standard Attributes

common-name EXTENSION-ATTRIBUTE

issuerAltName EXTENSION ::= {CommonName {
        SYNTAX  GeneralNames
        IDENTIFIED BY 1}

CommonName id-ce-issuerAltName }

subjectDirectoryAttributes EXTENSION ::= PrintableString (SIZE (1..ub-common-name-length))

teletex-common-name EXTENSION-ATTRIBUTE {
        SYNTAX  AttributesSyntax
        IDENTIFIED BY id-ce-subjectDirectoryAttributes }

AttributesSyntax ::=
                {TeletexCommonName SEQUENCE SIZE (1..MAX) OF Attribute

-- Certification path constraints extensions --

basicConstraints EXTENSION ::= {
        SYNTAX  BasicConstraintsSyntax
        IDENTIFIED BY 2}

TeletexCommonName id-ce-basicConstraints }

BasicConstraintsSyntax ::= TeletexString (SIZE (1..ub-common-name-length))

teletex-organization-name EXTENSION-ATTRIBUTE SEQUENCE {
        cA                      BOOLEAN DEFAULT FALSE,
        pathLenConstraint       INTEGER (0..MAX) OPTIONAL }

nameConstraints EXTENSION ::=
                {TeletexOrganizationName {
        SYNTAX  NameConstraintsSyntax
        IDENTIFIED BY 3}

TeletexOrganizationName id-ce-nameConstraints }

NameConstraintsSyntax ::=
                TeletexString (SIZE (1..ub-organization-name-length))

teletex-personal-name EXTENSION-ATTRIBUTE SEQUENCE {
        permittedSubtrees       [0]     GeneralSubtrees OPTIONAL,
        excludedSubtrees        [1]     GeneralSubtrees OPTIONAL }

GeneralSubtrees ::=
                {TeletexPersonalName IDENTIFIED BY 4}

TeletexPersonalName SEQUENCE SIZE (1..MAX) OF GeneralSubtree

GeneralSubtree ::= SET SEQUENCE {
   surname
        base                    GeneralName,
        minimum         [0] TeletexString (SIZE (1..ub-surname-length)),
   given-name     BaseDistance DEFAULT 0,
        maximum         [1] TeletexString
                (SIZE (1..ub-given-name-length)) OPTIONAL,
   initials [2] TeletexString (SIZE (1..ub-initials-length)) OPTIONAL,
   generation-qualifier [3] TeletexString (SIZE
                (1..ub-generation-qualifier-length))     BaseDistance OPTIONAL }

teletex-organizational-unit-names EXTENSION-ATTRIBUTE

BaseDistance ::=
   {TeletexOrganizationalUnitNames INTEGER (0..MAX)

policyConstraints EXTENSION ::= {
        SYNTAX  PolicyConstraintsSyntax
        IDENTIFIED BY 5}

TeletexOrganizationalUnitNames id-ce-policyConstraints }

PolicyConstraintsSyntax ::= SEQUENCE SIZE
        (1..ub-organizational-units) (1..MAX) OF TeletexOrganizationalUnitName

TeletexOrganizationalUnitName SEQUENCE {
        requireExplicitPolicy   [0] SkipCerts OPTIONAL,
        inhibitPolicyMapping    [1] SkipCerts OPTIONAL }

SkipCerts ::= TeletexString
                        (SIZE (1..ub-organizational-unit-name-length)) INTEGER (0..MAX)



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pds-name EXTENSION-ATTRIBUTE


-- Basic CRL extensions --

cRLNumber EXTENSION ::= {PDSName {
        SYNTAX  CRLNumber
        IDENTIFIED BY 7}

PDSName ::= PrintableString (SIZE (1..ub-pds-name-length))

physical-delivery-country-name EXTENSION-ATTRIBUTE id-ce-cRLNumber }

CRLNumber ::=
   {PhysicalDeliveryCountryName IDENTIFIED BY 8}

PhysicalDeliveryCountryName INTEGER (0..MAX)

reasonCode EXTENSION ::= CHOICE {
   x121-dcc-code NumericString (SIZE (ub-country-name-numeric-length)),
   iso-3166-alpha2-code PrintableString
                        (SIZE (ub-country-name-alpha-length)) }

postal-code EXTENSION-ATTRIBUTE ::= {PostalCode
        SYNTAX  CRLReason
        IDENTIFIED BY 9}

PostalCode id-ce-reasonCode }

CRLReason ::= CHOICE ENUMERATED {
   numeric-code NumericString (SIZE (1..ub-postal-code-length)),
   printable-code PrintableString (SIZE (1..ub-postal-code-length))
        unspecified             (0),
        keyCompromise           (1),
        cACompromise            (2),
        affiliationChanged      (3),
        superseded              (4),
        cessationOfOperation    (5),
        certificateHold         (6),
        removeFromCRL           (8) }

physical-delivery-office-name EXTENSION-ATTRIBUTE ::=
                        {PhysicalDeliveryOfficeName IDENTIFIED BY 10}

PhysicalDeliveryOfficeName ::= PDSParameter

physical-delivery-office-number EXTENSION-ATTRIBUTE

instructionCode EXTENSION ::=
   {PhysicalDeliveryOfficeNumber {
        SYNTAX  HoldInstruction
        IDENTIFIED BY 11}

PhysicalDeliveryOfficeNumber ::= PDSParameter

extension-OR-address-components EXTENSION-ATTRIBUTE id-ce-instructionCode }

HoldInstruction ::=
   {ExtensionORAddressComponents IDENTIFIED BY 12}

ExtensionORAddressComponents OBJECT IDENTIFIER

-- holdinstructions described in this specification, from ANSI x9

-- ANSI x9 arc holdinstruction arc
holdInstruction OBJECT IDENTIFIER ::= PDSParameter

physical-delivery-personal-name EXTENSION-ATTRIBUTE {
     joint-iso-ccitt(2) member-body(2) us(840) x9cm(10040) 2}

-- ANSI X9 holdinstructions referenced by this standard
id-holdinstruction-none OBJECT IDENTIFIER ::=
   {PhysicalDeliveryPersonalName IDENTIFIED BY 13}

PhysicalDeliveryPersonalName {holdInstruction 1}
id-holdinstruction-callissuer OBJECT IDENTIFIER ::= PDSParameter

physical-delivery-organization-name EXTENSION-ATTRIBUTE {holdInstruction 2}
id-holdinstruction-reject OBJECT IDENTIFIER ::=
   {PhysicalDeliveryOrganizationName {holdInstruction 3}

invalidityDate EXTENSION ::= {
        SYNTAX  GeneralizedTime
        IDENTIFIED BY 14}

PhysicalDeliveryOrganizationName ::= PDSParameter

extension-physical-delivery-address-components EXTENSION-ATTRIBUTE id-ce-invalidityDate }

-- CRL distribution points and delta-CRL extensions --

cRLDistributionPoints EXTENSION ::=
   {ExtensionPhysicalDeliveryAddressComponents {
        SYNTAX  CRLDistPointsSyntax
        IDENTIFIED BY 15}

ExtensionPhysicalDeliveryAddressComponents ::= PDSParameter id-ce-cRLDistributionPoints }



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unformatted-postal-address EXTENSION-ATTRIBUTE ::=
                        {UnformattedPostalAddress IDENTIFIED BY 16}

UnformattedPostalAddress


CRLDistPointsSyntax ::= SET {
   printable-address SEQUENCE SIZE (1..ub-pds-physical-address-lines) (1..MAX) OF
           PrintableString (SIZE (1..ub-pds-parameter-length)) DistributionPoint

DistributionPoint ::= SEQUENCE {
        distributionPoint       [0]     DistributionPointName OPTIONAL,
   teletex-string TeletexString (SIZE
                         (1..ub-unformatted-address-length))
        reasons         [1]     ReasonFlags OPTIONAL,
        cRLIssuer               [2]     GeneralNames OPTIONAL }

street-address EXTENSION-ATTRIBUTE

DistributionPointName ::=
                {StreetAddress IDENTIFIED BY 17}

StreetAddress CHOICE {
        fullName                [0]     GeneralNames,
        nameRelativeToCRLIssuer [1]     RelativeDistinguishedName }

ReasonFlags ::= PDSParameter

post-office-box-address EXTENSION-ATTRIBUTE BIT STRING {
        unused                  (0),
        keyCompromise           (1),
        caCompromise            (2),
        affiliationChanged      (3),
        superseded              (4),
        cessationOfOperation    (5),
        certificateHold         (6) }

issuingDistributionPoint EXTENSION ::=
                {PostOfficeBoxAddress {
        SYNTAX  IssuingDistPointSyntax
        IDENTIFIED BY 18}

PostOfficeBoxAddress id-ce-issuingDistributionPoint }

IssuingDistPointSyntax ::= PDSParameter

poste-restante-address EXTENSION-ATTRIBUTE SEQUENCE {
        distributionPoint       [0] DistributionPointName OPTIONAL,
        onlyContainsUserCerts   [1] BOOLEAN DEFAULT FALSE,
        onlyContainsCACerts     [2] BOOLEAN DEFAULT FALSE,
        onlySomeReasons         [3] ReasonFlags OPTIONAL,
        indirectCRL             [4] BOOLEAN DEFAULT FALSE }

certificateIssuer EXTENSION ::=
                {PosteRestanteAddress {
        SYNTAX          GeneralNames
        IDENTIFIED BY 19}

PosteRestanteAddress ::= PDSParameter

unique-postal-name EXTENSION-ATTRIBUTE id-ce-certificateIssuer }

deltaCRLIndicator EXTENSION ::=
                {UniquePostalName {
        SYNTAX          BaseCRLNumber
        IDENTIFIED BY 20}

UniquePostalName id-ce-deltaCRLIndicator }

BaseCRLNumber ::= PDSParameter

local-postal-attributes EXTENSION-ATTRIBUTE CRLNumber

-- Object identifier assignments for ISO certificate extensions --
id-ce   OBJECT IDENTIFIER       ::=
                {LocalPostalAttributes IDENTIFIED BY 21}

LocalPostalAttributes     {joint-iso-ccitt(2) ds(5) 29}

id-ce-subjectDirectoryAttributes   OBJECT IDENTIFIER ::= PDSParameter

PDSParameter {id-ce 9}
id-ce-subjectKeyIdentifier         OBJECT IDENTIFIER ::= SET {
   printable-string PrintableString
            (SIZE(1..ub-pds-parameter-length)) OPTIONAL,
   teletex-string TeletexString
            (SIZE(1..ub-pds-parameter-length)) OPTIONAL }

extended-network-address EXTENSION-ATTRIBUTE {id-ce 14}
id-ce-keyUsage                     OBJECT IDENTIFIER ::=
                {ExtendedNetworkAddress IDENTIFIED BY 22}

ExtendedNetworkAddress {id-ce 15}
id-ce-privateKeyUsagePeriod        OBJECT IDENTIFIER ::= CHOICE {
        e163-4-address SEQUENCE {
                number [0] NumericString
                   (SIZE (1..ub-e163-4-number-length)),
                sub-address [1] NumericString {id-ce 16}



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                   (SIZE (1..ub-e163-4-sub-address-length)) OPTIONAL},
        psap-address [0] PresentationAddress }

terminal-type EXTENSION-ATTRIBUTE


id-ce-subjectAltName               OBJECT IDENTIFIER ::= {TerminalType IDENTIFIED BY {id-ce 17}
id-ce-issuerAltName                OBJECT IDENTIFIER ::= {id-ce 18}
id-ce-basicConstraints             OBJECT IDENTIFIER ::= {id-ce 19}
id-ce-cRLNumber                    OBJECT IDENTIFIER ::= {id-ce 20}
id-ce-reasonCode                   OBJECT IDENTIFIER ::= {id-ce 21}
id-ce-instructionCode              OBJECT IDENTIFIER ::= {id-ce 23}

TerminalType
id-ce-invalidityDate               OBJECT IDENTIFIER ::= INTEGER {
   telex (3),
   teletex (4),
   g3-facsimile (5),
   g4-facsimile (6),
   ia5-terminal (7),
   videotex (8) } (0..ub-integer-options) {id-ce 24}
id-ce-deltaCRLIndicator            OBJECT IDENTIFIER ::= {id-ce 27}
id-ce-issuingDistributionPoint     OBJECT IDENTIFIER ::= {id-ce 28}
id-ce-certificateIssuer            OBJECT IDENTIFIER ::= {id-ce 29}
id-ce-nameConstraints              OBJECT IDENTIFIER ::= {id-ce 30}
id-ce-cRLDistributionPoints        OBJECT IDENTIFIER ::= {id-ce 31}
id-ce-certificatePolicies          OBJECT IDENTIFIER ::= {id-ce 32}
id-ce-policyMappings               OBJECT IDENTIFIER ::= {id-ce 33}
id-ce-policyConstraints            OBJECT IDENTIFIER ::= {id-ce 36}
id-ce-authorityKeyIdentifier       OBJECT IDENTIFIER ::= {id-ce 35}
id-ce-extKeyUsage                  OBJECT IDENTIFIER ::= {id-ce 37}

--      Extension Domain-defined Attributes

teletex-domain-defined-attributes EXTENSION-ATTRIBUTE PKIX 1 extensions

authorityInfoAccess EXTENSION ::=
   {TeletexDomainDefinedAttributes {
        SYNTAX  AuthorityInfoAccessSyntax
        IDENTIFIED BY 6}

TeletexDomainDefinedAttributes id-pe-authorityInfoAccess }

AuthorityInfoAccessSyntax  ::=
        SEQUENCE SIZE
   (1..ub-domain-defined-attributes) (1..MAX) OF TeletexDomainDefinedAttribute

TeletexDomainDefinedAttribute AccessDescription

AccessDescription  ::=  SEQUENCE {
    type TeletexString
         (SIZE (1..ub-domain-defined-attribute-type-length)),
    value TeletexString
         (SIZE (1..ub-domain-defined-attribute-value-length))
        accessMethod          OBJECT IDENTIFIER,
        accessLocation        GeneralName  }

--  specifications of Upper Bounds
--  must be regarded as mandatory
--  from Annex B of ITU-T X.411
--  Reference Definition of MTS Parameter Upper Bounds

--      Upper Bounds
ub-common-name-length INTEGER ::= 64
ub-country-name-alpha-length INTEGER ::= 2
ub-country-name-numeric-length INTEGER ::= 3
ub-domain-defined-attributes INTEGER ::= 4
ub-domain-defined-attribute-type-length INTEGER ::= 8
ub-domain-defined-attribute-value-length INTEGER ::= 128
ub-domain-name-length INTEGER ::= 16
ub-extension-attributes INTEGER ::= 256
ub-e163-4-number-length INTEGER

id-pe-authorityInfoAccess OBJECT IDENTIFIER ::= 15
ub-e163-4-sub-address-length INTEGER { id-pe 1 }

id-ad-caIssuers OBJECT IDENTIFIER ::= 40
ub-generation-qualifier-length INTEGER { id-ad 2 }

-- PKIX policy qualifier definitions

noticeToUser CERT-POLICY-QUALIFIER ::= 3
ub-given-name-length INTEGER {
     POLICY-QUALIFIER-ID    id-qt-cps QUALIFIER-TYPE       CPSuri}

pointerToCPS CERT-POLICY-QUALIFIER ::= 16
ub-initials-length INTEGER {
     POLICY-QUALIFIER-ID    id-qt-unotice QUALIFIER-TYPE   UserNotice}

id-qt-cps      OBJECT IDENTIFIER ::= 5
ub-integer-options INTEGER  { id-qt 1 }
id-qt-unotice  OBJECT IDENTIFIER ::= 256
ub-numeric-user-id-length INTEGER  { id-qt 2 }

CPSuri ::= 32 IA5String




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ub-organization-name-length INTEGER ::= 64
ub-organizational-unit-name-length INTEGER ::= 32
ub-organizational-units INTEGER ::= 4
ub-pds-name-length INTEGER ::= 16
ub-pds-parameter-length INTEGER ::= 30
ub-pds-physical-address-lines INTEGER ::= 6
ub-postal-code-length INTEGER ::= 16
ub-surname-length INTEGER ::= 40
ub-terminal-id-length INTEGER


UserNotice ::= 24
ub-unformatted-address-length INTEGER SEQUENCE {
     noticeRef        NoticeReference OPTIONAL,
     explicitText     DisplayText OPTIONAL}

NoticeReference ::= 180
ub-x121-address-length SEQUENCE {
     organization     DisplayText,
     noticeNumbers    SEQUENCE OF INTEGER }

DisplayText ::= 16

-- Note - upper bounds on TeletexString are measured in characters.
-- A significantly greater number of octets will be required to hold
-- such a value.  As a minimum, 16 octets, or twice the specified upper
-- bound, whichever is the larger, should be allowed. CHOICE {
     visibleString    VisibleString  (SIZE (1..200)),
     bmpString        BMPString      (SIZE (1..200)),
     utf8String       UTF8String     (SIZE (1..200)) }


END



Appendix C. ASN.1 Notes

   The construct

       SEQUENCE "SEQUENCE SIZE (1..MAX) OF OF" appears in several ASN.1
   constructs. A valid ASN.1 sequence will have zero or more entries.
   The SIZE (1..MAX) construct constrains the sequence to have at least
   one entry. MAX indicates the upper bound is unspecified. Implementations Implementa-
   tions are free to choose an upper bound that suits their environment.

   The construct

      positiveInt "positiveInt ::= INTEGER (0..MAX) (0..MAX)" defines positiveInt
   as a subtype of INTEGER containing integers greater than or equal to
   zero.  The upper bound is unspecified. Implementations are free to
   select an upper bound that suits their environment.

   The character string type PrintableString supports a very basic Latin
   character set:  the lower case letters 'a' through 'z', upper case
   letters 'A' through 'Z', the digits '0' through '9', eleven special
   characters ' " ( ) + , - . / : ? and space.

   The character string type TeletexString is a superset of Printable-
   String.  TeletexString supports a fairly standard (ascii-like) Latin
   character set, Latin characters with non-spacing accents and Japanese



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   characters.

   The character string type UniversalString supports any of the charac-
   ters allowed by ISO 10646-1. ISO 10646 is the Universal multiple-
   octet coded Character Set (UCS).  ISO 10646-1 specifes the architec-
   ture and the "basic multilingual plane" - a large standard character
   set which includes all major world character standards.

   The character string type UTF8String will be introduced in the 1998



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   version of ASN.1.  UTF8String is a universal type and has been
   assigned tag number 12.  The content of UTF8String was defined by RFC
   2044 and updated in RFC 2279, "UTF-8, a transformation Format of ISP
   10646."  ISO is expected to formally add UTF8String to the list of
   choices for DirectoryString in 1998 as well.

   In anticipation of these changes, and in conformance with IETF Best
   Practices codified in RFC 2277, IETF Policy on Character Sets and
   Languages, this document includes UTF8String as a choice in Directo-
   ryString and the CPS qualifier extensions.

Appendix D. Examples

   This section contains four examples; examples: three certificates and a CRL.
   The first two certificates and the CRL comprise a minimal certifica-
   tion path.

   Section D.1 contains two annotated hex dumps of a "self-signed" cer-
   tificate issued by a CA whose distinguished name is
   cn=us,o=gov,ou=nist.  The certificate contains a DSA public key with
   parameters, and is signed by the corresponding DSA private key. The
   first hex dump is a basic dump of the ASN.1 encoding and does not not
   reflect the fact that the object is a certificate. The second dump
   identfies the values of the various certificate fields.

   Section D.2 contains  an annotated hex dump of an end-entity certifi-
   cate.  The end entity certificate contains a DSA public key, and is
   signed by the private key corresponding to the "self-signed" certifi-
   cate in section D.1.   The first hex dump is a basic dump of the
   ASN.1 encoding and does not not reflect the fact that the object is a
   certificate. The second dump identfies the values of the various cer-
   tificate fields.

   Section D.3 contains a dump of an end entity certificate which con-
   tains an RSA public key and is signed with RSA and MD5.  (This  This certi-
   ficate is not part of the minimal certification path.) path.

   Section D.4 contains an annotated hex dump of a CRL.  The CRL is
   issued by the CA whose distinguished name is cn=us,o=gov,ou=nist and



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   the list of revoked certifcates includes the end entity certificate
   presented in D.2.  The hex dump is a basic dump of the ASN.1 encod-
   ing.

D.1 Certificate

   This section contains an annotated hex dump of a 662 byte version 3
   certificate.  The certificate contains the following information:
   (a) the serial number is 17 (11 hex);



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   (b) the certificate is signed with DSA and the SHA-1 hash algorithm;
   (c) the issuer's distinguished name is OU=nist;O=gov;C=US
   (d) and the subject's distinguished name is OU=nist;O=gov;C=US
   (e) the certificate was issued on June 30, 1997 and will expire on
   December 31, 1997;
   (f) the certificate contains a 1024 bit DSA public key; key with parame-
   ters; and
   (g) the certificate is a CA certificate (as indicated through the
   basic constraints extension.)

D.1.1 ASN.1 Dump of "Self-Signed" Certificate

get 0, len=662 (662 bytes in file)

0000 30 82 02 92  658: SEQUENCE
0004 30 82 02 52  594: . SEQUENCE
0008 a0 03          3: . . [0]
0010 02 01          1: . . . INTEGER 2
0013 02 01          1: . . INTEGER 17
0016 30 09          9: . . SEQUENCE
0018 06 07          7: . . . OID 1.2.840.10040.4.3: dsa-with-sha
0027 30 2a         42: . . SEQUENCE
0029 31 0b         11: . . . SET
0031 30 09          9: . . . . SEQUENCE
0033 06 03          3: . . . . . OID 2.5.4.6: C
0038 13 02          2: . . . . . PrintableString  'US'
0042 31 0c         12: . . . SET
0044 30 0a         10: . . . . SEQUENCE
0046 06 03          3: . . . . . OID 2.5.4.10: O
0051 13 03          3: . . . . . PrintableString  'gov'
0056 31 0d         13: . . . SET
0058 30 0b         11: . . . . SEQUENCE
0060 06 03          3: . . . . . OID 2.5.4.11: OU
0065 13 04          4: . . . . . PrintableString  'nist'
0071 30 1e         30: . . SEQUENCE
0073 17 0d         13: . . . UTCTime  '970630000000Z'
0088 17 0d         13: . . . UTCTime  '971231000000Z'
0103 30 2a         42: . . SEQUENCE
0105 31 0b         11: . . . SET
0107 30 09          9: . . . . SEQUENCE
0109 06 03          3: . . . . . OID 2.5.4.6: C



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0114 13 02          2: . . . . . PrintableString  'US'
0118 31 0c         12: . . . SET
0120 30 0a         10: . . . . SEQUENCE
0122 06 03          3: . . . . . OID 2.5.4.10: O
0127 13 03          3: . . . . . PrintableString  'gov'
0132 31 0d         13: . . . SET
0134 30 0b         11: . . . . SEQUENCE
0136 06 03          3: . . . . . OID 2.5.4.11: OU
0141 13 04          4: . . . . . PrintableString  'nist'



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0147 30 82 01 b4  436: . . SEQUENCE
0151 30 82 01 29  297: . . . SEQUENCE
0155 06 07          7: . . . . OID 1.2.840.10040.4.1: dsa
0164 30 82 01 1c  284: . . . . SEQUENCE
0168 02 81 80     128: . . . . . INTEGER
                     : d4 38 02 c5 35 7b d5 0b a1 7e 5d 72 59 63 55 d3
                     : 45 56 ea e2 25 1a 6b c5 a4 ab aa 0b d4 62 b4 d2
                     : 21 b1 95 a2 c6 01 c9 c3 fa 01 6f 79 86 83 3d 03
                     : 61 e1 f1 92 ac bc 03 4e 89 a3 c9 53 4a f7 e2 a6
                     : 48 cf 42 1e 21 b1 5c 2b 3a 7f ba be 6b 5a f7 0a
                     : 26 d8 8e 1b eb ec bf 1e 5a 3f 45 c0 bd 31 23 be
                     : 69 71 a7 c2 90 fe a5 d6 80 b5 24 dc 44 9c eb 4d
                     : f9 da f0 c8 e8 a2 4c 99 07 5c 8e 35 2b 7d 57 8d
0299 02 14         20: . . . . . INTEGER
                     : a7 83 9b f3 bd 2c 20 07 fc 4c e7 e8 9f f3 39 83
                     : 51 0d dc dd
0321 02 81 80     128: . . . . . INTEGER
                     : 0e 3b 46 31 8a 0a 58 86 40 84 e3 a1 22 0d 88 ca
                     : 90 88 57 64 9f 01 21 e0 15 05 94 24 82 e2 10 90
                     : d9 e1 4e 10 5c e7 54 6b d4 0c 2b 1b 59 0a a0 b5
                     : a1 7d b5 07 e3 65 7c ea 90 d8 8e 30 42 e4 85 bb
                     : ac fa 4e 76 4b 78 0e df 6c e5 a6 e1 bd 59 77 7d
                     : a6 97 59 c5 29 a7 b3 3f 95 3e 9d f1 59 2d f7 42
                     : 87 62 3f f1 b8 6f c7 3d 4b b8 8d 74 c4 ca 44 90
                     : cf 67 db de 14 60 97 4a d1 f7 6d 9e 09 94 c4 0d
0452 03 81 84     132: . . . BIT STRING  (0 unused bits)
                     : 02 81 80 aa 98 ea 13 94 a2 db f1 5b 7f 98 2f 78
                     : e7 d8 e3 b9 71 86 f6 80 2f 40 39 c3 da 3b 4b 13
                     : 46 26 ee 0d 56 c5 a3 3a 39 b7 7d 33 c2 6b 5c 77
                     : 92 f2 55 65 90 39 cd 1a 3c 86 e1 32 eb 25 bc 91
                     : c4 ff 80 4f 36 61 bd cc e2 61 04 e0 7e 60 13 ca
                     : c0 9c dd e0 ea 41 de 33 c1 f1 44 a9 bc 71 de cf
                     : 59 d4 6e da 44 99 3c 21 64 e4 78 54 9d d0 7b ba
                     : 4e f5 18 4d 5e 39 30 bf e0 d1 f6 f4 83 25 4f 14
                     : aa 71 e1
0587 a3 0d         13: . . [3]
0589 30 0b         11: . . . SEQUENCE
0591 30 09          9: . . . . SEQUENCE
0593 06 03          3: . . . . . OID 2.5.29.19: basicConstraints



Housley, Ford, Polk, & Solo                                   [Page 103]





INTERNET DRAFT                                            March 25, 1998
0598 04 02          2: . . . . . OCTET STRING
                     : 30 00
0602 30 09          9: . SEQUENCE
0604 06 07          7: . . OID 1.2.840.10040.4.3: dsa-with-sha
0613 03 2f         47: . BIT STRING  (0 unused bits)
                     : 30 2c 02 14 a0 66 c1 76 33 99 13 51 8d 93 64 2f
                     : ca 13 73 de 79 1a 7d 33 02 14 5d 90 f6 ce 92 4a
                     : bf 29 11 24 80 28 a6 5a 8e 73 b6 76 02 68

------- extensions ----------

printber -s 456 pkix-ex1.ber
get 0, len=131 (662 bytes in file)
0000 02 81 80     128: INTEGER
                     : aa 98 ea 13 94 a2 db f1 5b 7f 98 2f 78 e7 d8 e3
                     : b9 71 86 f6 80 2f 40 39 c3 da 3b 4b 13 46 26 ee
                     : 0d 56 c5 a3 3a 39 b7 7d 33 c2 6b 5c 77 92 f2 55
                     : 65 90 39 cd 1a 3c 86 e1 32 eb 25 bc 91 c4 ff 80
                     : 4f 36 61 bd cc e2 61 04 e0 7e 60 13 ca c0 9c dd
                     : e0 ea 41 de 33 c1 f1 44 a9 bc 71 de cf 59 d4 6e
                     : da 44 99 3c 21 64 e4 78 54 9d d0 7b ba 4e f5 18
                     : 4d 5e 39 30 bf e0 d1 f6 f4 83 25 4f 14 aa 71 e1




Housley, Ford, Polk, & Solo                                   [Page 117]





INTERNET DRAFT                                             June 16, 1998


D.1.2 Pretty Print of "Self-Signed" Certificate

----------
decode: 0-OK, len=662 (662 bytes in file)

      Version: v3
Serial Number: 17
Signature Alg: dsa-with-sha (1.2.840.10040.4.3)
       Issuer: C=US, O=gov, OU=nist
     Validity: from 970630000000Z
                 to 971231000000Z
      Subject: OU=nist, O=gov, C=US
SubjectPKInfo: dsa (1.2.840.10040.4.1)
       params:
        02 81 80 d4 38 02 c5 35 7b d5 0b a1 7e 5d 72 59
        63 55 d3 45 56 ea e2 25 1a 6b c5 a4 ab aa 0b d4
        62 b4 d2 21 b1 95 a2 c6 01 c9 c3 fa 01 6f 79 86
        83 3d 03 61 e1 f1 92 ac bc 03 4e 89 a3 c9 53 4a
        f7 e2 a6 48 cf 42 1e 21 b1 5c 2b 3a 7f ba be 6b
        5a f7 0a 26 d8 8e 1b eb ec bf 1e 5a 3f 45 c0 bd
        31 23 be 69 71 a7 c2 90 fe a5 d6 80 b5 24 dc 44
        9c eb 4d f9 da f0 c8 e8 a2 4c 99 07 5c 8e 35 2b
        7d 57 8d 02 14 a7 83 9b f3 bd 2c 20 07 fc 4c e7



Housley, Ford, Polk, & Solo                                   [Page 104]





INTERNET DRAFT                                            March 25, 1998
        e8 9f f3 39 83 51 0d dc dd 02 81 80 0e 3b 46 31
        8a 0a 58 86 40 84 e3 a1 22 0d 88 ca 90 88 57 64
        9f 01 21 e0 15 05 94 24 82 e2 10 90 d9 e1 4e 10
        5c e7 54 6b d4 0c 2b 1b 59 0a a0 b5 a1 7d b5 07
        e3 65 7c ea 90 d8 8e 30 42 e4 85 bb ac fa 4e 76
        4b 78 0e df 6c e5 a6 e1 bd 59 77 7d a6 97 59 c5
        29 a7 b3 3f 95 3e 9d f1 59 2d f7 42 87 62 3f f1
        b8 6f c7 3d 4b b8 8d 74 c4 ca 44 90 cf 67 db de
        14 60 97 4a d1 f7 6d 9e 09 94 c4 0d
   Public Key:
        00 02 81 80 aa 98 ea 13 94 a2 db f1 5b 7f 98 2f
        78 e7 d8 e3 b9 71 86 f6 80 2f 40 39 c3 da 3b 4b
        13 46 26 ee 0d 56 c5 a3 3a 39 b7 7d 33 c2 6b 5c
        77 92 f2 55 65 90 39 cd 1a 3c 86 e1 32 eb 25 bc
        91 c4 ff 80 4f 36 61 bd cc e2 61 04 e0 7e 60 13
        ca c0 9c dd e0 ea 41 de 33 c1 f1 44 a9 bc 71 de
        cf 59 d4 6e da 44 99 3c 21 64 e4 78 54 9d d0 7b
        ba 4e f5 18 4d 5e 39 30 bf e0 d1 f6 f4 83 25 4f
        14 aa 71 e1
    issuerUID:
   subjectUID:
 1 extensions:
     Exten  1:   basicConstraints (2.5.29.19)
        30 00
Signature Alg: dsa-with-sha (1.2.840.10040.4.3)
    Sig Value: 368 bits:
        30 2c 02 14 a0 66 c1 76 33 99 13 51 8d 93 64 2f
        ca 13 73 de 79 1a 7d 33 02 14 5d 90 f6 ce 92 4a
        bf 29 11 24 80 28 a6 5a 8e 73 b6 76 02 68


------- extensions ----------

printber -s 616 pkix-ex1.ber
get 0, len=46 (662 bytes in file)
0000 30 2c         44: SEQUENCE
0002 02 14         20: . INTEGER
                     : 9d 2d 0c 75 ec ce 01 8d 93 64 2f
        ca 13 73 de 79 25 4c cd 7b dc fc 17 0e
                     : 0f 2a 22 ef
0024 1a 7d 33 02 14         20: . INTEGER
                     : 80 61 6f fb dc 71 cf 3f 09 62 b4 aa ad 4b 8c 28
                     : 68 d7 60 fe 5d 90 f6 ce 92 4a



Housley, Ford, Polk, & Solo                                   [Page 105] 118]





INTERNET DRAFT                                            March 25,                                             June 16, 1998


        bf 29 11 24 80 28 a6 5a 8e 73 b6 76 02 68

D.2 Certificate

   This section contains an annotated hex dump of a xxx 697 byte version 3
   certificate.  The certificate contains the following information:
   (a) the serial number is 18 (12 hex);
   (b) the certificate is signed with DSA and the SHA-1 hash algorithm;
   (c) the issuer's distinguished name is OU=nist;O=gov;C=US
   (d) and the subject's distinguished name is CN=Tim
   Polk;OU=nist;O=gov;C=US
   (e) the certificate was valid from July 30, 1997 and will expire on through December 1,
   1997;
   (f) the certificate contains a 1024 bit DSA public key;
   (g) the certificate is an end entity certificate unless external
   information is provided, certificate, as the basic constraints con-
   straints extension is not present;
   (h) the certificate includes one alternative name - an RFC 822
   address.


D.2.1 Basic ASN.1 Dump of "End Entity" Certificate

----------

get 0, len=697 (697 bytes in file)

0000 30 82 02 b5  693: SEQUENCE
0004 30 82 02 75  629: . SEQUENCE
0008 a0 03          3: . . [0]
0010 02 01          1: . . . INTEGER 2
0013 02 01          1: . . INTEGER 18
0016 30 09          9: . . SEQUENCE
0018 06 07          7: . . . OID 1.2.840.10040.4.3: dsa-with-sha
0027 30 2a         42: . . SEQUENCE
0029 31 0b         11: . . . SET
0031 30 09          9: . . . . SEQUENCE
0033 06 03          3: . . . . . OID 2.5.4.6: C
0038 13 02          2: . . . . . PrintableString  'US'
0042 31 0c         12: . . . SET
0044 30 0a         10: . . . . SEQUENCE
0046 06 03          3: . . . . . OID 2.5.4.10: O
0051 13 03          3: . . . . . PrintableString  'gov'
0056 31 0d         13: . . . SET
0058 30 0b         11: . . . . SEQUENCE
0060 06 03          3: . . . . . OID 2.5.4.11: OU
0065 13 04          4: . . . . . PrintableString  'nist'
0071 30 1e         30: . . SEQUENCE
0073 17 0d         13: . . . UTCTime  '970730000000Z'
0088 17 0d         13: . . . UTCTime  '971201000000Z'
0103 30 3d         61: . . SEQUENCE



Housley, Ford, Polk, & Solo                                   [Page 106] 119]





INTERNET DRAFT                                            March 25,                                             June 16, 1998


0105 31 0b         11: . . . SET
0107 30 09          9: . . . . SEQUENCE
0109 06 03          3: . . . . . OID 2.5.4.6: C
0114 13 02          2: . . . . . PrintableString  'US'
0118 31 0c         12: . . . SET
0120 30 0a         10: . . . . SEQUENCE
0122 06 03          3: . . . . . OID 2.5.4.10: O
0127 13 03          3: . . . . . PrintableString  'gov'
0132 31 0d         13: . . . SET
0134 30 0b         11: . . . . SEQUENCE
0136 06 03          3: . . . . . OID 2.5.4.11: OU
0141 13 04          4: . . . . . PrintableString  'nist'
0147 31 11         17: . . . SET
0149 30 0f         15: . . . . SEQUENCE
0151 06 03          3: . . . . . OID 2.5.4.3: CN
0156 13 08          8: . . . . . PrintableString  'Tim Polk'
0166 30 82 01 b4  436: . . SEQUENCE
0170 30 82 01 29  297: . . . SEQUENCE
0174 06 07          7: . . . . OID 1.2.840.10040.4.1: dsa
0183 30 82 01 1c  284: . . . . SEQUENCE
0187 02 81 80     128: . . . . . INTEGER
                     : d4 38 02 c5 35 7b d5 0b a1 7e 5d 72 59 63 55 d3
                     : 45 56 ea e2 25 1a 6b c5 a4 ab aa 0b d4 62 b4 d2
                     : 21 b1 95 a2 c6 01 c9 c3 fa 01 6f 79 86 83 3d 03
                     : 61 e1 f1 92 ac bc 03 4e 89 a3 c9 53 4a f7 e2 a6
                     : 48 cf 42 1e 21 b1 5c 2b 3a 7f ba be 6b 5a f7 0a
                     : 26 d8 8e 1b eb ec bf 1e 5a 3f 45 c0 bd 31 23 be
                     : 69 71 a7 c2 90 fe a5 d6 80 b5 24 dc 44 9c eb 4d
                     : f9 da f0 c8 e8 a2 4c 99 07 5c 8e 35 2b 7d 57 8d
0318 02 14         20: . . . . . INTEGER
                     : a7 83 9b f3 bd 2c 20 07 fc 4c e7 e8 9f f3 39 83
                     : 51 0d dc dd
0340 02 81 80     128: . . . . . INTEGER
                     : 0e 3b 46 31 8a 0a 58 86 40 84 e3 a1 22 0d 88 ca
                     : 90 88 57 64 9f 01 21 e0 15 05 94 24 82 e2 10 90
                     : d9 e1 4e 10 5c e7 54 6b d4 0c 2b 1b 59 0a a0 b5
                     : a1 7d b5 07 e3 65 7c ea 90 d8 8e 30 42 e4 85 bb
                     : ac fa 4e 76 4b 78 0e df 6c e5 a6 e1 bd 59 77 7d
                     : a6 97 59 c5 29 a7 b3 3f 95 3e 9d f1 59 2d f7 42
                     : 87 62 3f f1 b8 6f c7 3d 4b b8 8d 74 c4 ca 44 90
                     : cf 67 db de 14 60 97 4a d1 f7 6d 9e 09 94 c4 0d
0471 03 81 84     132: . . . BIT STRING  (0 unused bits)
                     : 02 81 80 a8 63 b1 60 70 94 7e 0b 86 08 93 0c 0d
                     : 08 12 4a 58 a9 af 9a 09 38 54 3b 46 82 fb 85 0d
                     : 18 8b 2a 77 f7 58 e8 f0 1d d2 18 df fe e7 e9 35
                     : c8 a6 1a db 8d 3d 3d f8 73 14 a9 0b 39 c7 95 f6
                     : 52 7d 2d 13 8c ae 03 29 3c 4e 8c b0 26 18 b6 d8
                     : 11 1f d4 12 0c 13 ce 3f f1 c7 05 4e df e1 fc 44



Housley, Ford, Polk, & Solo                                   [Page 107] 120]





INTERNET DRAFT                                            March 25,                                             June 16, 1998


                     : fd 25 34 19 4a 81 0d dd 98 42 ac d3 b6 91 0c 7f
                     : 16 72 a3 a0 8a d7 01 7f fb 9c 93 e8 99 92 c8 42
                     : 47 c6 43
0606 a3 1d         29: . . [3]
0608 30 1b         27: . . . SEQUENCE
0610 30 19         25: . . . . SEQUENCE
0612 06 03          3: . . . . . OID 2.5.29.17: subjectAltName
0617 04 12         18: . . . . . OCTET STRING
                     : 30 10 81 0e 77 70 6f 6c 6b 40 6e 69 73 74 2e 67
                     : 6f 76
0637 30 09          9: . SEQUENCE
0639 06 07          7: . . OID 1.2.840.10040.4.3: dsa-with-sha
0648 03 2f         47: . BIT STRING  (0 unused bits)
                     : 30 2c 02 14 3c 02 e0 ab d9 5d 05 77 75 15 71 58
                     : 92 29 48 c4 1c 54 df fc 02 14 5b da 53 98 7f c5
                     : 33 df c6 09 b2 7a e3 6f 97 70 1e 14 ed 94

-------- extensions ----------

printber -s 475 pkix-ex2.ber
get 0, len=131 (697 bytes in file)
0000 02 81 80     128: INTEGER
                     : a8 63 b1 60 70 94 7e 0b 86 08 93 0c 0d 08 12 4a
                     : 58 a9 af 9a 09 38 54 3b 46 82 fb 85 0d 18 8b 2a
                     : 77 f7 58 e8 f0 1d d2 18 df fe e7 e9 35 c8 a6 1a
                     : db 8d 3d 3d f8 73 14 a9 0b 39 c7 95 f6 52 7d 2d
                     : 13 8c ae 03 29 3c 4e 8c b0 26 18 b6 d8 11 1f d4
                     : 12 0c 13 ce 3f f1 c7 05 4e df e1 fc 44 fd 25 34
                     : 19 4a 81 0d dd 98 42 ac d3 b6 91 0c 7f 16 72 a3
                     : a0 8a d7 01 7f fb 9c 93 e8 99 92 c8 42 47 7f c5
                     : 33 df c6 43 09 b2 7a e3 6f 97 70 1e 14 ed 94

D.2.2 Pretty Print of "End Entity" Certificate

----------
decode: 0-OK, len=697 (697 bytes in file)

      Version: v3
Serial Number: 18
Signature Alg: dsa-with-sha (1.2.840.10040.4.3)
       Issuer: C=US, O=gov, OU=nist
     Validity: from 970730000000Z
                 to 971201000000Z
      Subject: CN=Tim Polk, OU=nist, O=gov, C=US
SubjectPKInfo: dsa (1.2.840.10040.4.1)
       params:
        02 81 80 d4 38 02 c5 35 7b d5 0b a1 7e 5d 72 59
        63 55 d3 45 56 ea e2 25 1a 6b c5 a4 ab aa 0b d4



Housley, Ford, Polk, & Solo                                   [Page 108]





INTERNET DRAFT                                            March 25, 1998
        62 b4 d2 21 b1 95 a2 c6 01 c9 c3 fa 01 6f 79 86
        83 3d 03 61 e1 f1 92 ac bc 03 4e 89 a3 c9 53 4a
        f7 e2 a6 48 cf 42 1e 21 b1 5c 2b 3a 7f ba be 6b
        5a f7 0a 26 d8 8e 1b eb ec bf 1e 5a 3f 45 c0 bd
        31 23 be 69 71 a7 c2 90 fe a5 d6 80 b5 24 dc 44
        9c eb 4d f9 da f0 c8 e8 a2 4c 99 07 5c 8e 35 2b
        7d 57 8d 02 14 a7 83 9b f3 bd 2c 20 07 fc 4c e7
        e8 9f f3 39 83 51 0d dc dd 02 81 80 0e 3b 46 31
        8a 0a 58 86 40 84 e3 a1 22 0d 88 ca 90 88 57 64
        9f 01 2