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PKCS #9: Selected Object Classes and Attribute Types Version 2.0
RFC 2985

Document Type RFC - Informational (November 2000) Errata
Was draft-nystrom-pkcs9-v2 (individual)
Authors Magnus Nyström , Burt Kaliski
Last updated 2020-01-21
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RFC 2985
Network Working Group                                           M. Nystrom
Request for Comments: 2985                                      B. Kaliski
Category: Informational                                       RSA Security
                                                             November 2000

          PKCS #9: Selected Object Classes and Attribute Types
                              Version 2.0

Status of this Memo

   This memo provides information for the Internet community.  It does
   not specify an Internet standard of any kind.  Distribution of this
   memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2000).  All Rights Reserved.

Abstract

   This memo represents a republication of PKCS #9 v2.0 from RSA
   Laboratories' Public-Key Cryptography Standards (PKCS) series, and
   change control is retained within the PKCS process.  The body of this
   document, except for the security considerations section, is taken
   directly from that specification.

   This memo provides a selection of object classes and attribute types
   for use in conjunction with public-key cryptography and Lightweight
   Directory Access Protocol (LDAP) accessible directories.  It also
   includes ASN.1 syntax for all constructs.

Table of Contents

   1.  Introduction ................................................. 2
   2.  Definitions, notation and document convention ................ 2
   2.1  Definitions ................................................. 2
   2.2  Notation and document convention ............................ 3
   3.  Overview ..................................................... 4
   4.  Auxiliary object classes ..................................... 5
   4.1  The "pkcsEntity" auxiliary object class ..................... 5
   4.2  The "naturalPerson" auxiliary object class .................. 6
   5.  Selected attribute types ..................................... 6
   5.1  Attribute types for use with the "pkcsEntity" object class .. 6
   5.2  Attribute types for use with the "naturalPerson" object class 7
   5.3  Attribute types for use in PKCS #7 data .................... 12
   5.4  Attribute types for use in PKCS #10 certificate requests ... 16

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   5.5  Attribute types for use in PKCS #12 "PFX" PDUs or PKCS #15
        tokens ..................................................... 17
   5.6  Attributes defined in S/MIMIE .............................. 18
   6.  Matching rules .............................................. 19
   6.1  Case ignore match .......................................... 19
   6.2  Signing time match ......................................... 20
   7.  Security Considerations ..................................... 20
   8.  Authors' Addresses .......................................... 21
   A.  ASN.1 module ................................................ 22
   B.  BNF schema summary .......................................... 30
   B.1  Syntaxes ................................................... 30
   B.2  Object classes ............................................. 31
   B.3  Attribute types ............................................ 32
   B.4  Matching rules ............................................. 36
   C.  Intellectual property considerations ........................ 37
   D.  Revision history ............................................ 37
   E.  References .................................................. 39
   F.  Contact information & About PKCS ............................ 41
   Full Copyright Statement ........................................ 41

1. Introduction

   This document defines two new auxiliary object classes, pkcsEntity
   and naturalPerson, and selected attribute types for use with these
   classes.  It also defines some attribute types for use in conjunction
   with PKCS #7 [14] (and S/MIME CMS [3]) digitally signed messages,
   PKCS #10 [16] certificate-signing requests, PKCS #12 [17] personal
   information exchanges and PKCS #15 [18] cryptographic tokens.
   Matching rules for use with these attributes are also defined,
   whenever necessary.

2. Definitions, notation and document conventions

 2.1 Definitions

   For the purposes of this document, the following definitions apply.

   ASN.1           Abstract Syntax Notation One, as defined in [5].

   Attributes      An ASN.1 type that specifies a set of attributes.
                   Each attribute contains an attribute type (specified
                   by object identifier) and one or more attribute
                   values.  Some attribute types are restricted in their
                   definition to have a single value; others may have
                   multiple values.  This type is defined in [7].

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   CertificationRequestInfo
                   An ASN.1 type that specifies a subject name, a public
                   key, and a set of attributes.  This type is defined
                   in [16].

   ContentInfo     An ASN.1 type that specifies content exchanged
                   between entities.  The contentType field, which has
                   type OBJECT IDENTIFIER, specifies the content type,
                   and the content field, whose type is defined by the
                   contentType field, contains the content value.  This
                   type is defined in [14] and [3].

   PrivateKeyInfo  A type that specifies a private key and a set of
                   extended attributes.  This type and the associated
                   EncryptedPrivateKeyInfo type are defined in [15].

   SignerInfo      A type that specifies per-signer information in the
                   signed-data content type, including a set of
                   attributes authenticated by the signer, and a set of
                   attributes not authenticated by the signer.  This
                   type is defined in [14] and [3].

   DER             Distinguished Encoding Rules for ASN.1, as defined in
                   [6].

   UCS             Universal Multiple-Octet Coded Character Set, as
                   defined in [11].

   UTF8String      UCS Transformation Format encoded string.  The UTF-8
                   encoding is defined in [11].

 2.2 Notation and document conventions

   In this document, all attribute type and object class definitions are
   written in the ASN.1 value notation defined in [5].  Appendix B
   contains most of these definitions written in the augmented BNF
   notation defined in [2] as well.  This has been done in an attempt to
   simplify the task of integrating this work into LDAP [22] development
   environments.

   The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [1].

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3. Overview

   This document specifies two new auxiliary object classes, pkcsEntity
   and naturalPerson, and some new attribute types and matching rules.
   All ASN.1 object classes, attributes, matching rules and types are
   exported for use in other environments.

   Attribute types defined in this document that are useful in
   conjunction with storage of PKCS-related data and the pkcsEntity
   object class includes PKCS #12 PFX PDUs, PKCS #15 tokens and
   encrypted private keys.

   Attribute types defined in this document that are useful in
   conjunction with PKCS #10 certificate requests and the naturalPerson
   object class includes electronic-mail address, pseudonym,
   unstructured name, and unstructured address.

   Attribute types defined in this document that are useful in PKCS #7
   digitally signed messages are content type, message digest, signing
   time, sequence number, random nonce and countersignature.  The
   attributes would be used in the authenticatedAttributes and
   unauthenticatedAttributes fields of a SignerInfo or an
   AuthenticatedData ([3]) value.

   Attribute types that are useful especially in PKCS #10 certification
   requests are the challenge password and the extension-request
   attribute.  The attributes would be used in the attributes field of a
   CertificationRequestInfo value.

   Note - The attributes types (from [8]) in Table 1, and probably
   several others, might also be helpful in PKCS #10, PKCS #12 and PKCS
   #15-aware applications.

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       businessCategory            preferredDeliveryMethod
       commonName                  presentationAddress
       countryName                 registeredAddress
       description                 roleOccupant
       destinationIndicator        serialNumber
       facsimileTelephoneNumber    stateOrProvinceName
       iSDNAddress                 streetAddress
       localityName                supportedApplicationContext
       member                      surname
       objectClass                 telephoneNumber
       organizationName            teletexTerminalIdentifier
       physicalDeliveryOfficeName  telexNumber
       postalAddress               title
       postalCode                  x121Address
       postOfficeBox

   Table 1: ISO/IEC 9594-6 attribute types useful in PKCS documents

4. Auxiliary object classes

   This document defines two new auxiliary object classes: pkcsEntity
   and naturalPerson.

 4.1 The pkcsEntity auxiliary object class

   The pkcsEntity object class is a general-purpose auxiliary object
   class that is intended to hold attributes about PKCS-related
   entities.  It has been designed for use within directory services
   based on the LDAP protocol [22] and the X.500 family of protocols,
   where support for PKCS-defined attributes is considered useful.

   pkcsEntity OBJECT-CLASS ::=     {
           SUBCLASS OF { top }
           KIND auxiliary
           MAY CONTAIN { PKCSEntityAttributeSet }
           ID pkcs-9-oc-pkcsEntity
   }

   PKCSEntityAttributeSet ATTRIBUTE ::= {
           pKCS7PDU |
           userPKCS12 |
           pKCS15Token |
           encryptedPrivateKeyInfo,
           ... -- For future extensions
   }

   Attributes in the PKCSEntityAttributeSet are defined in Section 5.

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 4.2 The naturalPerson auxiliary object class

   The naturalPerson object class is a general-purpose auxiliary object
   class that is intended to hold attributes about human beings.  It has
   been designed for use within directory services based on the LDAP
   protocol [22] and the X.500 family of protocols, where support for
   these attributes is considered useful.

   naturalPerson OBJECT-CLASS      ::=     {
           SUBCLASS OF { top }
           KIND auxiliary
           MAY CONTAIN { NaturalPersonAttributeSet }
           ID pkcs-9-oc-naturalPerson
   }

   NaturalPersonAttributeSet ATTRIBUTE ::= {
           emailAddress |
           unstructuredName |
           unstructuredAddress |
           dateOfBirth |
           placeOfBirth |
           gender |
           countryOfCitizenship |
           countryOfResidence |
           pseudonym |
           serialNumber,
           ... -- For future extensions
   }

   Attributes in the NaturalPersonAttributeSet are defined in Section 5.

5. Selected attribute types

 5.1 Attribute types for use with the "pkcsEntity" object class

  5.1.1 PKCS #7 PDU

   PKCS #7 provides several formats for enveloped, signed and otherwise
   protected data.  When such information is stored in a directory
   service, the pKCS7PDU attribute may be used.

   pKCS7PDU ATTRIBUTE ::= {
           WITH SYNTAX ContentInfo
           ID pkcs-9-at-pkcs7PDU
   }

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  5.1.2 PKCS #12 token

   PKCS #12 provides a format for exchange of personal identity
   information.  When such information is stored in a directory service,
   the userPKCS12 attribute should be used.

   userPKCS12 ATTRIBUTE ::= {
           WITH SYNTAX PFX
           ID pkcs-9-at-userPKCS12
   }

   This type was originally defined in [20].

  5.1.3 PKCS #15 token

   PKCS #15 provides a format for cryptographic tokens.  When software
   variants of such tokens are stored in a directory service, the
   pKCS15Token attribute should be used.

   pKCS15Token ATTRIBUTE ::= {
           WITH SYNTAX PKCS15Token
           ID pkcs-9-at-pkcs15Token
   }

  5.1.4 PKCS #8 encrypted private key information

   PKCS #8 provides a format for encrypted private keys.  When such
   information is stored in a directory service, the
   encryptedPrivateKeyInfo attribute should be used.

   encryptedPrivateKeyInfo ATTRIBUTE ::= {
           WITH SYNTAX EncryptedPrivateKeyInfo
           ID pkcs-9-at-encryptedPrivateKeyInfo
   }

 5.2 Attribute types for use with the "naturalPerson" object class

  5.2.1 Electronic-mail address

   The emailAddress attribute type specifies the electronic-mail address
   or addresses of a subject as an unstructured ASCII string.  The
   interpretation of electronic-mail addresses is intended to be
   specified by certificate issuers etc.; no particular interpretation
   is required.

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   emailAddress ATTRIBUTE ::= {
           WITH SYNTAX IA5String (SIZE(1..pkcs-9-ub-emailAddress))
           EQUALITY MATCHING RULE pkcs9CaseIgnoreMatch
           ID pkcs-9-at-emailAdress
   }

   An electronic-mail address attribute can have multiple attribute
   values.  When comparing two email addresses, case is irrelevant.  The
   pkcs9CaseIgnoreMatch is defined in Section 6.

   Note - It is likely that other standards bodies overseeing
   electronic-mail systems will, or have, registered electronic-mail
   address attribute types specific to their system.  The electronic-
   mail address attribute type defined here was intended as a short-term
   substitute for those specific attribute types, but is included here
   for backwards-compatibility reasons.

  5.2.2 Unstructured name

   The unstructuredName attribute type specifies the name or names of a
   subject as an unstructured ASCII string.  The interpretation of
   unstructured names is intended to be specified by certificate issuers
   etc.; no particular interpretation is required.

   unstructuredName ATTRIBUTE ::= {
           WITH SYNTAX PKCS9String {pkcs-9-ub-unstructuredName}
           EQUALITY MATCHING RULE pkcs9CaseIgnoreMatch
           ID pkcs-9-at-unstructuredName
   }

   PKCS9String { INTEGER : maxSize} ::= CHOICE {
           ia5String       IA5String (SIZE(1..maxSize)),
           directoryString DirectoryString {maxSize}
   }

   An unstructured-name attribute can have multiple attribute values.
   When comparing two unstructured names, case is irrelevant.

   The PKCS9String type is defined as a choice of IA5String and
   DirectoryString.  Applications SHOULD use the IA5String type when
   generating attribute values in accordance with this version of this
   document, unless internationalization issues makes this impossible.
   In that case, the UTF8String alternative of the DirectoryString
   alternative is the preferred choice.  PKCS #9-attribute processing
   systems MUST be able to recognize and process all string types in
   PKCS9String values.

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   Note - Version 1.1 of this document defined unstructuredName as
   having the syntax IA5String, but did contain a note explaining that
   this might be changed to a CHOICE of different string types in future
   versions.  To better accommodate international names, this type has
   been extended to also include a directory string in this version of
   this document.  Since [21] does not support a directory string type
   containing IA5Strings, a separate syntax object identifier has been
   defined (see [21] and Appendix B).

  5.2.3 Unstructured address

   The unstructuredAddress attribute type specifies the address or
   addresses of a subject as an unstructured directory string.  The
   interpretation of unstructured addresses is intended to be specified
   by certificate issuers etc; no particular interpretation is required.
   A likely interpretation is as an alternative to the postalAddress
   attribute type defined in [8].

   unstructuredAddress ATTRIBUTE ::= {
           WITH SYNTAX DirectoryString {pkcs-9-ub-unstructuredAddress}
           EQUALITY MATCHING RULE caseIgnoreMatch
           ID pkcs-9-at-unstructuredAddress
   }

   An unstructured-address attribute can have multiple attribute values.
   The caseIgnoreMatch matching rule is defined in [8].

   Note 1 - It is recommended to use the ASN.1 type TeletexString's
   new-line character (hexadecimal code 0d) as a line separator in
   multi-line addresses.

   Note 2 - Previous versions of this document defined
   unstructuredAddress as having the following syntax:

   CHOICE {
           teletexString TeletexString,
           printableString PrintableString,
   }

   But also mentioned the possibility of a future definition as follows:

   CHOICE {
           teletexString TeletexString,
           printableString PrintableString,
           universalString UniversalString
   }

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   In this version of this document, the X.520 type DirectoryString has
   been used in order to be more aligned with international standards
   and current practice.  When generating attribute values in accordance
   with this version of this document, applications SHOULD use the
   PrintableString alternative unless internationalization issues makes
   this impossible.  In those cases, the UTF8String alternative SHOULD
   be used.  PKCS #9-attribute processing systems MUST be able to
   recognize and process all string types in DirectoryString values.

  5.2.4 Date of birth

   The dateOfBirth attribute specifies the date of birth for the subject
   it is associated with.

   dateOfBirth ATTRIBUTE ::= {
           WITH SYNTAX GeneralizedTime
           EQUALITY MATCHING RULE generalizedTimeMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-dateOfBirth
   }

   dateOfBirth attributes must be single-valued.  The
   generalizedTimeMatch matching rule is defined in [8].

  5.2.5 Place of birth

   The placeOfBirth attribute specifies the place of birth for the
   subject it is associated with.

   placeOfBirth ATTRIBUTE ::= {
           WITH SYNTAX DirectoryString {pkcs-9-ub-placeOfBirth}
           EQUALITY MATCHING RULE caseExactMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-placeOfBirth
   }

   placeOfBirth attributes must be single-valued.  The caseExactMatch
   matching rule is defined in [8].

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  5.2.6 Gender

   The gender attribute specifies the gender of the subject it is
   associated with.

   gender ATTRIBUTE ::= {
           WITH SYNTAX PrintableString (SIZE(1) ^
                       FROM ("M" | "F" | "m" | "f"))
           EQUALITY MATCHING RULE caseIgnoreMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-gender
   }

   The letter "M" (or "m") represents "male" and the letter "F" (or "f")
   represents "female".  gender attributes must be single-valued.

  5.2.7 Country of citizenship

   The countryOfCitizenship attribute specifies the (claimed) countries
   of citizenship for the subject it is associated with.  It SHALL be a
   2-letter acronym of a country in accordance with [4].

   countryOfCitizenship ATTRIBUTE ::= {
           WITH SYNTAX PrintableString (SIZE(2) ^ CONSTRAINED BY {
           -- Must be a two-letter country acronym in accordance with
           -- ISO/IEC 3166 --})
           EQUALITY MATCHING RULE caseIgnoreMatch
           ID pkcs-9-at-countryOfCitizenship
   }

   Attributes of this type need not be single-valued.

  5.2.8 Country of residence

   The countryOfResidence attribute specifies the (claimed) country of
   residence for the subject is associated with.  It SHALL be a 2-letter
   acronym of a country in accordance with [4].

   countryOfResidence ATTRIBUTE ::= {
           WITH SYNTAX PrintableString (SIZE(2) ^ CONSTRAINED BY {
           -- Must be a two-letter country acronym in accordance with
           -- ISO/IEC 3166 --})
           EQUALITY MATCHING RULE caseIgnoreMatch
           ID pkcs-9-at-countryOfResidence
   }

   Attributes of this type need not be single-valued, since it is
   possible to be a resident of several countries.

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  5.2.9 Pseudonym

   The pseudonym attribute type shall contain a pseudonym of a subject.
   The exact interpretation of pseudonyms is intended to be specified by
   certificate issuers etc.; no particular interpretation is required.

   pseudonym ATTRIBUTE ::= {
           WITH SYNTAX DirectoryString {pkcs-9-ub-pseudonym}
           EQUALITY MATCHING RULE caseExactMatch
           ID id-at-pseudonym
   }

   Note - The pseudonym attribute has received an object identifier in
   the joint-iso-itu-t object identifier tree.

   The caseExactMatch matching rule is defined in [8].

  5.2.10 Serial number

   The serialNumber attribute is defined in [8].

 5.3 Attribute types for use in PKCS #7 data

  5.3.1 Content type

   The contentType attribute type specifies the content type of the
   ContentInfo value being signed in PKCS #7 (or S/MIME CMS) digitally
   signed data.  In such data, the contentType attribute type is
   required if there are any PKCS #7 authenticated attributes.

   contentType ATTRIBUTE ::= {
           WITH SYNTAX ContentType
           EQUALITY MATCHING RULE objectIdentifierMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-contentType
   }

   ContentType ::= OBJECT IDENTIFIER

   As indicated, content-type attributes must have a single attribute
   value.  For two content-type values to match, their octet string
   representation must be of equal length and corresponding octets
   identical.  The objectIdentifierMatch matching rule is defined in
   [7].

   Note - This attribute type is described in [3] as well.

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  5.3.2 Message digest

   The messageDigest attribute type specifies the message digest of the
   contents octets of the DER-encoding of the content field of the
   ContentInfo value being signed in PKCS #7 digitally signed data,
   where the message digest is computed under the signer's message
   digest algorithm.  The message-digest attribute type is required in
   these cases if there are any PKCS #7 authenticated attributes
   present.

   messageDigest ATTRIBUTE ::= {
           WITH SYNTAX MessageDigest
           EQUALITY MATCHING RULE octetStringMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-messageDigest
   }

   MessageDigest ::= OCTET STRING

   As indicated, a message-digest attribute must have a single attribute
   value.  For two messageDigest values to match, their octet string
   representation must be of equal length and corresponding octets
   identical.  The octetStringMatch matching rule is defined in [8].

   Note - This attribute is described in [3] as well.

  5.3.3 Signing time

   The signingTime attribute type is intended for PKCS #7 digitally
   signed data.  It specifies the time at which the signer (purportedly)
   performed the signing process.

   signingTime ATTRIBUTE ::= {
           WITH SYNTAX SigningTime
           EQUALITY MATCHING RULE signingTimeMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-signingTime
   }

   SigningTime ::= Time -- imported from ISO/IEC 9594-8

   A signing-time attribute must have a single attribute value.

   The signingTimeMatch matching rule (defined in Section 6.1) returns
   TRUE if an attribute value represents the same time as a presented
   value.

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   Quoting from [3]:
   "Dates between 1 January 1950 and 31 December 2049 (inclusive) MUST
   be encoded as UTCTime.  Any dates with year values before 1950 or
   after 2049 MUST be encoded as GeneralizedTime.  [Further,] UTCTime
   values MUST be expressed in Greenwich Mean Time (Zulu) and MUST
   include seconds (i.e., times are YYMMDDHHMMSSZ), even where the
   number of seconds is zero.  Midnight (GMT) must be represented as
   "YYMMDD000000Z".  Century information is implicit, and the century
   shall be determined as follows:

   - Where YY is greater than or equal to 50, the year shall be
     interpreted as 19YY; and
   - Where YY is less than 50, the year shall be interpreted as 20YY.

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

   Note 1 - The definition of SigningTime matches the definition of Time
   specified in [10].

   Note 2 - No requirement is imposed concerning the correctness of the
   signing time, and acceptance of a purported signing time is a matter
   of a recipient's discretion.  It is expected, however, that some
   signers, such as time-stamp servers, will be trusted implicitly.

  5.3.4 Random nonce

   The randomNonce attribute type is intended for PKCS #7 digitally
   signed data.  It may be used by a signer unable (or unwilling) to
   specify the time at which the signing process was performed.  Used in
   a correct manner, it will make it possible for the signer to protect
   against certain attacks, i.e. replay attacks.

   randomNonce ATTRIBUTE ::= {
           WITH SYNTAX RandomNonce
           EQUALITY MATCHING RULE octetStringMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-randomNonce
   }

   RandomNonce ::= OCTET STRING (SIZE(4..MAX))
           -- At least four bytes long

   A random nonce attribute must have a single attribute value.

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  5.3.5 Sequence number

   The sequenceNumber attribute type is intended for PKCS #7 digitally
   signed data.  A signer wishing to associate a sequence number to all
   signature operations (much like a physical checkbook) may use it as
   an alternative to the randomNonce attribute.  Used in a correct
   manner, it will make it possible for the signer to protect against
   certain attacks, i.e. replay attacks.

   sequenceNumber ATTRIBUTE ::= {
           WITH SYNTAX SequenceNumber
           EQUALITY MATCHING RULE integerMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-sequenceNumber
   }

   SequenceNumber ::= INTEGER (1..MAX)

   A sequence number attribute must have a single attribute value.

   The integerMatch matching rule is defined in [8].

  5.3.6 Countersignature

   The counterSignature attribute type specifies one or more signatures
   on the content octets of the DER encoding of the encryptedDigest
   field of a SignerInfo value in PKCS #7 digitally signed data.  Thus,
   the countersignature attribute type countersigns (signs in serial)
   another signature.  The countersignature attribute must be an
   unauthenticated PKCS #7 attribute; it cannot be an authenticated
   attribute.

   counterSignature ATTRIBUTE ::= {
           WITH SYNTAX SignerInfo
           ID pkcs-9-at-counterSignature
   }

   Countersignature values have the same meaning as SignerInfo values
   for ordinary signatures (see Section 9 of [14] and Section 5.3 of
   [3]), except that:

   1. The authenticatedAttributes field must contain a messageDigest
   attribute if it contains any other attributes, but need not contain a
   contentType attribute, as there is no content type for
   countersignatures; and

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   2. The input to the message-digesting process is the content octets
   of the DER encoding of the signatureValue field of the SignerInfo
   value with which the attribute is associated.

   A countersignature attribute can have multiple attribute values.

   Note 1 - The fact that a countersignature is computed on a signature
   (encrypted digest) means that the countersigning process need not
   know the original content input to the signing process.  This has
   advantages both in efficiency and in confidentiality.

   Note 2 - A countersignature, since it has type SignerInfo, can itself
   contain a countersignature attribute.  Thus it is possible to
   construct arbitrarily long series of countersignatures.

 5.4 Attribute types for use with PKCS #10 certificate requests

  5.4.1 Challenge password

   The challengePassword attribute type specifies a password by which an
   entity may request certificate revocation.  The interpretation of
   challenge passwords is intended to be specified by certificate
   issuers etc; no particular interpretation is required.

   challengePassword ATTRIBUTE ::= {
           WITH SYNTAX DirectoryString {pkcs-9-ub-challengePassword}
           EQUALITY MATCHING RULE caseExactMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-challengePassword
   }

   A challenge-password attribute must have a single attribute value.

   ChallengePassword attribute values generated in accordance with this
   version of this document SHOULD use the PrintableString encoding
   whenever possible.  If internationalization issues make this
   impossible, the UTF8String alternative SHOULD be used.  PKCS #9-
   attribute processing systems MUST be able to recognize and process
   all string types in DirectoryString values.

   Note - Version 1.1 of this document defined challengePassword as
   having the syntax CHOICE {PrintableString, T61String}, but did
   contain a note explaining that this might be changed to a CHOICE of
   different string types in the future See also Note 2 in section
   5.2.3.

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  5.4.2 Extension request

   The extensionRequest attribute type may be used to carry information
   about certificate extensions the requester wishes to be included in a
   certificate.

   extensionRequest ATTRIBUTE ::= {
           WITH SYNTAX ExtensionRequest
           SINGLE VALUE TRUE
           ID pkcs-9-at-extensionRequest
   }

   ExtensionRequest ::= Extensions

   The Extensions type is imported from [10].

  5.4.3 Extended-certificate attributes (deprecated)

   The extendedCertificateAttributes attribute type specified a set of
   attributes for a PKCS #6 [13] extended certificate in a PKCS #10
   certification request (the value of the extended certificate-
   attributes attribute would become the extension in the requested PKCS
   #6 extended certificate).  Since the status of PKCS #6 is historic
   after the introduction of X.509 v3 certificates [10], the use of this
   attribute is deprecated.

   extendedCertificateAttributes ATTRIBUTE ::= {
           WITH SYNTAX SET OF Attribute
           SINGLE VALUE TRUE
           ID pkcs-9-at-extendedCertificateAttributes
   }

   An extended certificate attributes attribute must have a single
   attribute value (that value is a set, which itself may contain
   multiple values, but there must be only one set).

 5.5 Attributes for use in PKCS #12 "PFX" PDUs or PKCS #15 tokens

  5.5.1 Friendly name

   The friendlyName attribute type specifies a user-friendly name of the
   object it belongs to.  It is referenced in [17].

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   friendlyName ATTRIBUTE ::= {
           WITH SYNTAX BMPString (SIZE(1..pkcs-9-ub-friendlyName))
           EQUALITY MATCHING RULE caseIgnoreMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-friendlyName
   }

   As indicated, friendlyName attributes must have a single attribute
   value.

  5.5.2 Local key identifier

   The localKeyId attribute type specifies an identifier for a
   particular key.  It is only to be used locally in applications.  This
   attribute is referenced in [17].

   localKeyId ATTRIBUTE ::= {
           WITH SYNTAX OCTET STRING
           EQUALITY MATCHING RULE octetStringMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-localKeyId
   }

   As indicated, localKeyId attributes must have a single attribute
   value.  For two localKeyId values to match, their octet string
   representation must be of equal length and corresponding octets
   identical.

 5.6 Attributes defined in S/MIME

   S/MIME (c.f. [12]) defines some attributes and object identifiers in
   the PKCS #9 object identifier tree.  For completeness, they are
   mentioned here.

  5.6.1 Signing description

   The signingDescription attribute is intended to provide a short
   synopsis of a message that can be used to present a user with an
   additional confirmation step before committing to a cryptographic
   operation.  In most cases, the replication of the "Subject:" line
   from the header of a message should be sufficient and is recommended.

   signingDescription ATTRIBUTE ::= {
           WITH SYNTAX DirectoryString {pkcs-9-ub-signingDescription}
           EQUALITY MATCHING RULE caseIgnoreMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-signingDescription
   }

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  5.6.2 S/MIME capabilities

   The syntax and semantics of the smimeCapabilities attribute is
   defined in [12].  It is included here for the sake of completeness.

   smimeCapabilities ATTRIBUTE ::= {
           WITH SYNTAX SMIMECapabilities
           SINGLE VALUE
           ID pkcs-9-at-smimeCapabilities
   }

   SMIMECapabilities ::= SEQUENCE OF SMIMECapability

   SMIMECapability ::= SEQUENCE {
           algorithm  ALGORITHM.&id ({SMIMEv3Algorithms}),
           parameters ALGORITHM.&Type ({SMIMEv3Algorithms}{@algorithm})
   }

   SMIMEv3Algorithms ALGORITHM ::= {... -- See RFC 2633 -- }

6. Matching rules

   This section defines matching rules used in the definition of
   attributes in this document.

 6.1 Case ignore match

   The pkcs9CaseIgnoreMatch rule compares for equality a presented
   string with an attribute value of type PKCS9String, without regard to
   the case (upper or lower) of the strings (e.g. "Pkcs" and "PKCS"
   match).

   pkcs9CaseIgnoreMatch MATCHING-RULE ::= {
           SYNTAX  PKCS9String {pkcs9-ub-match}
           ID              id-mr-pkcs9CaseIgnoreMatch
   }

   The rule returns TRUE if the strings are the same length and
   corresponding characters are identical except possibly with regard to
   case.

   Where the strings being matched are of different ASN.1 syntax, the
   comparison proceeds as normal so long as the corresponding characters
   are in both character sets.  Otherwise matching fails.

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 6.2 Signing time match

   The signingTimeMatch rule compares for equality a presented value
   with an attribute value of type SigningTime.

   signingTimeMatch MATCHING-RULE ::= {
           SYNTAX SigningTime
           ID pkcs-9-mr-signingTimeMatch
   }

   The rule returns TRUE if the attribute value represents the same time
   as the presented value.  If a time is specified with seconds (or
   fractional seconds) absent, the number of seconds (fractional
   seconds) is assumed to be zero.

   Where the strings being matched are of different ASN.1 syntax, the
   comparison proceeds as follows:

   a) Convert both values to DER-encoded values of type GeneralizedTime,
     coordinated universal time.  If this is not possible the matching
     fails.

   b) Compare the strings for equality.  The rule returns TRUE if and
     only if the strings are of the same length and corresponding octets
     are identical.

7. Security Considerations

   Attributes of directory entries are used to provide descriptive
   information about the real-world objects they represent, which can be
   people, organizations or devices.  Most countries have privacy laws
   regarding the publication of information about people.

   The challengePassword attribute should not be stored un-encrypted in
   a directory.

   Users of directory-aware applications making use of attributes
   defined for use with the pkcsEntity object class should make sure
   that the class's attributes are adequately protected, since they may
   potentially be read by third parties.  If a password-protected value
   is stored (PKCS #8, #12 or #15), the directory should authenticate
   the requester before delivering the value to prevent an off-line
   password-search attack.  Note that this potentially raises non-
   repudiation issues since the directory itself can try a password
   search to recover a private value, if stored this way.

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8. Authors' Addresses

   Magnus Nystrom
   RSA Security
   Box 10704
   S-121 29 Stockholm
   Sweden

   EMail: magnus@rsasecurity.com

   Burt Kaliski
   RSA Security
   20 Crosby Drive
   Bedford, MA 01730 USA

   EMail: bkaliski@rsasecurity.com

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APPENDICES

A. ASN.1 module

   This appendix includes all of the ASN.1 type and value definitions
   contained in this document in the form of the ASN.1 module PKCS-9.

   PKCS-9 {iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1)
   pkcs-9(9) modules(0) pkcs-9(1)}

   DEFINITIONS IMPLICIT TAGS ::=

   BEGIN

   -- EXPORTS All --
   -- All types and values defined in this module is exported for use
   -- in other ASN.1 modules.

   IMPORTS

   informationFramework, authenticationFramework,
   selectedAttributeTypes, upperBounds , id-at
           FROM UsefulDefinitions {joint-iso-itu-t ds(5) module(1)
           usefulDefinitions(0) 3}

   ub-name
           FROM UpperBounds upperBounds

   OBJECT-CLASS, ATTRIBUTE, MATCHING-RULE, Attribute, top,
   objectIdentifierMatch
           FROM InformationFramework informationFramework

   ALGORITHM, Extensions, Time
           FROM AuthenticationFramework authenticationFramework

   DirectoryString, octetStringMatch, caseIgnoreMatch, caseExactMatch,
   generalizedTimeMatch, integerMatch, serialNumber
           FROM SelectedAttributeTypes selectedAttributeTypes

   ContentInfo, SignerInfo
           FROM CryptographicMessageSyntax {iso(1) member-body(2) us(840)
           rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) modules(0) cms(1)}

   EncryptedPrivateKeyInfo
           FROM PKCS-8 {iso(1) member-body(2) us(840) rsadsi(113549)
           pkcs(1) pkcs-8(8) modules(1) pkcs-8(1)}

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   PFX
           FROM PKCS-12 {iso(1) member-body(2) us(840) rsadsi(113549)
           pkcs(1) pkcs-12(12) modules(0) pkcs-12(1)}

   PKCS15Token
           FROM PKCS-15 {iso(1) member-body(2) us(840) rsadsi(113549)
           pkcs(1) pkcs-15(15) modules(1) pkcs-15(1)};

   -- Upper bounds

   pkcs-9-ub-pkcs9String         INTEGER ::= 255
   pkcs-9-ub-emailAddress        INTEGER ::= pkcs-9-ub-pkcs9String
   pkcs-9-ub-unstructuredName    INTEGER ::= pkcs-9-ub-pkcs9String
   pkcs-9-ub-unstructuredAddress INTEGER ::= pkcs-9-ub-pkcs9String
   pkcs-9-ub-challengePassword   INTEGER ::= pkcs-9-ub-pkcs9String
   pkcs-9-ub-friendlyName        INTEGER ::= pkcs-9-ub-pkcs9String
   pkcs-9-ub-signingDescription  INTEGER ::= pkcs-9-ub-pkcs9String
   pkcs-9-ub-match               INTEGER ::= pkcs-9-ub-pkcs9String
   pkcs-9-ub-pseudonym           INTEGER ::= ub-name
   pkcs-9-ub-placeOfBirth        INTEGER ::= ub-name

   -- Object Identifiers

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

     -- Main arcs
   pkcs-9-mo OBJECT IDENTIFIER ::= {pkcs-9 0}  -- Modules branch
   pkcs-9-oc OBJECT IDENTIFIER ::= {pkcs-9 24} -- Object class branch
   pkcs-9-at OBJECT IDENTIFIER ::= {pkcs-9 25} -- Attribute branch, for
                                               -- new  attributes
   pkcs-9-sx OBJECT IDENTIFIER ::= {pkcs-9 26} -- For syntaxes (RFC 2252)
   pkcs-9-mr OBJECT IDENTIFIER ::= {pkcs-9 27} -- Matching rules

     -- Object classes
   pkcs-9-oc-pkcsEntity    OBJECT IDENTIFIER ::= {pkcs-9-oc 1}
   pkcs-9-oc-naturalPerson OBJECT IDENTIFIER ::= {pkcs-9-oc 2}

     -- Attributes
   pkcs-9-at-emailAddress        OBJECT IDENTIFIER ::= {pkcs-9 1}
   pkcs-9-at-unstructuredName    OBJECT IDENTIFIER ::= {pkcs-9 2}
   pkcs-9-at-contentType         OBJECT IDENTIFIER ::= {pkcs-9 3}
   pkcs-9-at-messageDigest       OBJECT IDENTIFIER ::= {pkcs-9 4}
   pkcs-9-at-signingTime         OBJECT IDENTIFIER ::= {pkcs-9 5}
   pkcs-9-at-counterSignature    OBJECT IDENTIFIER ::= {pkcs-9 6}
   pkcs-9-at-challengePassword   OBJECT IDENTIFIER ::= {pkcs-9 7}
   pkcs-9-at-unstructuredAddress OBJECT IDENTIFIER ::= {pkcs-9 8}

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   pkcs-9-at-extendedCertificateAttributes
                                 OBJECT IDENTIFIER ::= {pkcs-9 9}

   -- Obsolete (?) attribute identifiers, purportedly from "tentative
   -- PKCS #9 draft"
   -- pkcs-9-at-issuerAndSerialNumber OBJECT IDENTIFIER ::= {pkcs-9 10}
   -- pkcs-9-at-passwordCheck         OBJECT IDENTIFIER ::= {pkcs-9 11}
   -- pkcs-9-at-publicKey             OBJECT IDENTIFIER ::= {pkcs-9 12}

   pkcs-9-at-signingDescription       OBJECT IDENTIFIER ::= {pkcs-9 13}
   pkcs-9-at-extensionRequest         OBJECT IDENTIFIER ::= {pkcs-9 14}
   pkcs-9-at-smimeCapabilities        OBJECT IDENTIFIER ::= {pkcs-9 15}

   -- Unused (?)
   -- pkcs-9-at-?                     OBJECT IDENTIFIER ::= {pkcs-9 17}
   -- pkcs-9-at-?                     OBJECT IDENTIFIER ::= {pkcs-9 18}
   -- pkcs-9-at-?                     OBJECT IDENTIFIER ::= {pkcs-9 19}

   pkcs-9-at-friendlyName             OBJECT IDENTIFIER ::= {pkcs-9 20}
   pkcs-9-at-localKeyId               OBJECT IDENTIFIER ::= {pkcs-9 21}
   pkcs-9-at-userPKCS12               OBJECT IDENTIFIER ::=
                                         {2 16 840 1 113730 3 1 216}
   pkcs-9-at-pkcs15Token              OBJECT IDENTIFIER ::= {pkcs-9-at 1}
   pkcs-9-at-encryptedPrivateKeyInfo  OBJECT IDENTIFIER ::= {pkcs-9-at 2}
   pkcs-9-at-randomNonce              OBJECT IDENTIFIER ::= {pkcs-9-at 3}
   pkcs-9-at-sequenceNumber           OBJECT IDENTIFIER ::= {pkcs-9-at 4}
   pkcs-9-at-pkcs7PDU                 OBJECT IDENTIFIER ::= {pkcs-9-at 5}

     -- IETF PKIX Attribute branch
   ietf-at                            OBJECT IDENTIFIER ::=
                                         {1 3 6 1 5 5 7 9}

   pkcs-9-at-dateOfBirth              OBJECT IDENTIFIER ::= {ietf-at 1}
   pkcs-9-at-placeOfBirth             OBJECT IDENTIFIER ::= {ietf-at 2}
   pkcs-9-at-gender                   OBJECT IDENTIFIER ::= {ietf-at 3}
   pkcs-9-at-countryOfCitizenship     OBJECT IDENTIFIER ::= {ietf-at 4}
   pkcs-9-at-countryOfResidence       OBJECT IDENTIFIER ::= {ietf-at 5}

     -- Syntaxes (for use with LDAP accessible directories)
   pkcs-9-sx-pkcs9String              OBJECT IDENTIFIER ::= {pkcs-9-sx 1}
   pkcs-9-sx-signingTime              OBJECT IDENTIFIER ::= {pkcs-9-sx 2}

     -- Matching rules
   pkcs-9-mr-caseIgnoreMatch          OBJECT IDENTIFIER ::= {pkcs-9-mr 1}
   pkcs-9-mr-signingTimeMatch         OBJECT IDENTIFIER ::= {pkcs-9-mr 2}

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     -- Arcs with attributes defined elsewhere
   smime                              OBJECT IDENTIFIER ::= {pkcs-9 16}

     -- Main arc for S/MIME (RFC 2633)
   certTypes                          OBJECT IDENTIFIER ::= {pkcs-9 22}

     -- Main arc for certificate types defined in PKCS #12
   crlTypes                           OBJECT IDENTIFIER ::= {pkcs-9 23}

     -- Main arc for crl types defined in PKCS #12

     -- Other object identifiers
   id-at-pseudonym                    OBJECT IDENTIFIER ::= {id-at 65}

   -- Useful types

   PKCS9String {INTEGER : maxSize} ::= CHOICE {
           ia5String IA5String (SIZE(1..maxSize)),
           directoryString DirectoryString {maxSize}
   }

   -- Object classes

   pkcsEntity OBJECT-CLASS ::= {
           SUBCLASS OF     { top }
           KIND            auxiliary
           MAY CONTAIN     { PKCSEntityAttributeSet }
           ID              pkcs-9-oc-pkcsEntity
   }

   naturalPerson OBJECT-CLASS ::= {
           SUBCLASS OF     { top }
           KIND            auxiliary
           MAY CONTAIN     { NaturalPersonAttributeSet }
           ID              pkcs-9-oc-naturalPerson
   }

   -- Attribute sets

   PKCSEntityAttributeSet ATTRIBUTE ::= {
           pKCS7PDU |
           userPKCS12 |
           pKCS15Token |
           encryptedPrivateKeyInfo,
           ... -- For future extensions
   }

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   NaturalPersonAttributeSet ATTRIBUTE ::= {
           emailAddress |
           unstructuredName |
           unstructuredAddress |
           dateOfBirth |
           placeOfBirth |
           gender |
           countryOfCitizenship |
           countryOfResidence |
           pseudonym |
           serialNumber,
           ... -- For future extensions
   }

   -- Attributes

   pKCS7PDU ATTRIBUTE ::= {
           WITH SYNTAX ContentInfo
           ID pkcs-9-at-pkcs7PDU
   }

   userPKCS12 ATTRIBUTE ::= {
           WITH SYNTAX PFX
           ID pkcs-9-at-userPKCS12
   }

   pKCS15Token ATTRIBUTE ::= {
           WITH SYNTAX PKCS15Token
           ID pkcs-9-at-pkcs15Token
   }

   encryptedPrivateKeyInfo ATTRIBUTE ::= {
           WITH SYNTAX EncryptedPrivateKeyInfo
           ID pkcs-9-at-encryptedPrivateKeyInfo
   }

   emailAddress ATTRIBUTE ::= {
           WITH SYNTAX IA5String (SIZE(1..pkcs-9-ub-emailAddress))
           EQUALITY MATCHING RULE pkcs9CaseIgnoreMatch
           ID pkcs-9-at-emailAddress
   }

   unstructuredName ATTRIBUTE ::= {
           WITH SYNTAX PKCS9String {pkcs-9-ub-unstructuredName}
           EQUALITY MATCHING RULE pkcs9CaseIgnoreMatch
           ID pkcs-9-at-unstructuredName
   }

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   unstructuredAddress ATTRIBUTE ::= {
           WITH SYNTAX DirectoryString {pkcs-9-ub-unstructuredAddress}
           EQUALITY MATCHING RULE caseIgnoreMatch
           ID pkcs-9-at-unstructuredAddress
   }

   dateOfBirth ATTRIBUTE ::= {
           WITH SYNTAX GeneralizedTime
           EQUALITY MATCHING RULE generalizedTimeMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-dateOfBirth
   }

   placeOfBirth ATTRIBUTE ::= {
           WITH SYNTAX DirectoryString {pkcs-9-ub-placeOfBirth}
           EQUALITY MATCHING RULE caseExactMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-placeOfBirth
   }

   gender ATTRIBUTE ::= {
           WITH SYNTAX PrintableString (SIZE(1) ^
                       FROM ("M" | "F" | "m" | "f"))
           EQUALITY MATCHING RULE caseIgnoreMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-gender
   }

   countryOfCitizenship ATTRIBUTE ::= {
           WITH SYNTAX PrintableString (SIZE(2))(CONSTRAINED BY {
           -- Must be a two-letter country acronym in accordance with
           -- ISO/IEC 3166 --})
           EQUALITY MATCHING RULE caseIgnoreMatch
           ID pkcs-9-at-countryOfCitizenship
   }

   countryOfResidence ATTRIBUTE ::= {
           WITH SYNTAX PrintableString (SIZE(2))(CONSTRAINED BY {
           -- Must be a two-letter country acronym in accordance with
           -- ISO/IEC 3166 --})
           EQUALITY MATCHING RULE caseIgnoreMatch
           ID pkcs-9-at-countryOfResidence
   }

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   pseudonym ATTRIBUTE ::= {
           WITH SYNTAX DirectoryString {pkcs-9-ub-pseudonym}
           EQUALITY MATCHING RULE caseExactMatch
           ID id-at-pseudonym
   }

   contentType ATTRIBUTE ::= {
           WITH SYNTAX ContentType
           EQUALITY MATCHING RULE objectIdentifierMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-contentType
   }

   ContentType ::= OBJECT IDENTIFIER

   messageDigest ATTRIBUTE ::= {
           WITH SYNTAX MessageDigest
           EQUALITY MATCHING RULE octetStringMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-messageDigest
   }

   MessageDigest ::= OCTET STRING

   signingTime ATTRIBUTE ::= {
           WITH SYNTAX SigningTime
           EQUALITY MATCHING RULE signingTimeMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-signingTime
   }

   SigningTime ::= Time -- imported from ISO/IEC 9594-8

   randomNonce ATTRIBUTE ::= {
           WITH SYNTAX RandomNonce
           EQUALITY MATCHING RULE octetStringMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-randomNonce
   }

   RandomNonce ::= OCTET STRING (SIZE(4..MAX))
           -- At least four bytes long

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   sequenceNumber ATTRIBUTE ::= {
           WITH SYNTAX SequenceNumber
           EQUALITY MATCHING RULE integerMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-sequenceNumber
   }

   SequenceNumber ::= INTEGER (1..MAX)

   counterSignature ATTRIBUTE ::= {
           WITH SYNTAX SignerInfo
           ID pkcs-9-at-counterSignature
   }

   challengePassword ATTRIBUTE ::= {
           WITH SYNTAX DirectoryString {pkcs-9-ub-challengePassword}
           EQUALITY MATCHING RULE caseExactMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-challengePassword
   }

   extensionRequest ATTRIBUTE ::= {
           WITH SYNTAX ExtensionRequest
           SINGLE VALUE TRUE
           ID pkcs-9-at-extensionRequest
   }

   ExtensionRequest ::= Extensions

   extendedCertificateAttributes ATTRIBUTE ::= {
           WITH SYNTAX SET OF Attribute
           SINGLE VALUE TRUE
           ID pkcs-9-at-extendedCertificateAttributes
   }

   friendlyName ATTRIBUTE ::= {
           WITH SYNTAX BMPString (SIZE(1..pkcs-9-ub-friendlyName))
           EQUALITY MATCHING RULE caseIgnoreMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-friendlyName
   }

   localKeyId ATTRIBUTE ::= {
           WITH SYNTAX OCTET STRING
           EQUALITY MATCHING RULE octetStringMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-localKeyId
   }

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   signingDescription ATTRIBUTE ::= {
           WITH SYNTAX DirectoryString {pkcs-9-ub-signingDescription}
           EQUALITY MATCHING RULE caseIgnoreMatch
           SINGLE VALUE TRUE
           ID pkcs-9-at-signingDescription
   }

   smimeCapabilities ATTRIBUTE ::= {
           WITH SYNTAX SMIMECapabilities
           SINGLE VALUE TRUE
           ID pkcs-9-at-smimeCapabilities
   }

   SMIMECapabilities ::= SEQUENCE OF SMIMECapability

   SMIMECapability ::= SEQUENCE {
           algorithm  ALGORITHM.&id ({SMIMEv3Algorithms}),
           parameters ALGORITHM.&Type ({SMIMEv3Algorithms}{@algorithm})
   }

   SMIMEv3Algorithms ALGORITHM ::= {...-- See RFC 2633 --}

    -- Matching rules

   pkcs9CaseIgnoreMatch MATCHING-RULE ::= {
           SYNTAX PKCS9String {pkcs-9-ub-match}
           ID pkcs-9-mr-caseIgnoreMatch
   }

   signingTimeMatch MATCHING-RULE ::= {
           SYNTAX SigningTime
           ID pkcs-9-mr-signingTimeMatch
   }

   END

B. BNF schema summary This appendix provides augmented BNF [2]
   definitions of the object class and most attribute types specified in
   this document along with their associated syntaxes and matching
   rules.  The ABNF definitions have been done in accordance with [21],
   in an attempt to ease integration with LDAP-accessible Directory
   systems.  Lines have been folded in some cases to improve
   readability.

 B.1 Syntaxes

   This section defines all syntaxes that are used in this document.

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  B.1.1 PKCS9String

   (
           1.2.840.113549.1.9.26.1
           DESC 'PKCS9String'
   )

   The encoding of a value in this syntax is the string value itself.

  B.1.2 SigningTime

   (
           1.2.840.113549.1.9.26.2
           DESC 'SigningTime'
   )

   Values in this syntax are encoded as printable strings, represented
   as specified in [5].  Note that the time zone must be specified.  For
   example, "199412161032Z".

 B.2 Object classes

  B.2.1 pkcsEntity

   (
           1.2.840.113549.1.9.24.1
           NAME 'pkcsEntity'
           SUP top
           AUXILIARY
           MAY (
           pKCS7PDU $ userPKCS12 $ pKCS15Token $ encryptedPrivateKeyInfo
           )
   )

  B.2.2 naturalPerson

   (
           1.2.840.113549.1.9.24.2
           NAME 'naturalPerson'
           SUP top
           AUXILIARY
           MAY (
           emailAddress $ unstructuredName $ unstructuredAddress $
           dateOfBirth & placeOfBirth & gender & countryOfCitizenship &
           countryOfResidence & pseudonym & serialNumber
           )
   )

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 B.3 Attribute types

  B.3.1 pKCS7PDU

   This attribute is to be stored and requested in binary form, as
   pKCS7PDU;binary.  The attribute values are BER- or DER-encoded
   ContentInfo values.

   (
           1.2.840.113549.1.9.25.5
           NAME 'pKCS7PDU'
           DESC 'PKCS #7 ContentInfo PDU'
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.5
   )

  B.3.2 userPKCS12

   This attribute is to be stored and requested in binary form, as
   userPKCS12;binary.  The attribute values are PFX PDUs stored as
   binary (BER- or DER-encoded) data.

   (
           2.16.840.1.113730.3.1.216
           NAME 'userPKCS12'
           DESC 'PKCS #12 PFX PDU for exchange of personal information'
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.5
   )

  B.3.3 pKCS15Token

   This attribute is to be stored and requested in binary form, as
   pKCS15Token;binary.  The attribute values are PKCS15Token PDUs stored
   as binary (BER- or DER-encoded) data.

   (
           1.2.840.113549.1.9.25.1
           NAME 'pKCS15Token'
           DESC 'PKCS #15 token PDU'
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.5
   )

  B.3.4 encryptedPrivateKeyInfo

   This attribute is to be stored and requested in binary form, as
   encryptedPrivateKeyInfo;binary.  The attribute values are
   EncryptedPrivateKeyInfo PDUs stored as binary (BER- or DER-encoded)
   data.

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   (
           1.2.840.113549.1.9.25.2
           NAME 'encryptedPrivateKeyInfo'
           DESC 'PKCS #8 encrypted private key info'
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.5
   )

  B.3.5 emailAddress

   (
           1.2.840.113549.1.9.1
           NAME 'emailAddress'
           DESC 'Email address'
           EQUALITY pkcs9CaseIgnoreMatch
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.26
   )

  B.3.6 unstructuredName

   (
           1.2.840.113549.1.9.2
           NAME 'unstructuredName'
           DESC 'PKCS #9 unstructured name'
           EQUALITY pkcs9CaseIgnoreMatch
           SYNTAX 1.2.840.113549.1.9.26.1
   )

  B.3.7 unstructuredAddress

   (
           1.2.840.113549.1.9.8
           NAME 'unstructuredAddress'
           DESC 'PKCS #9 unstructured address'
           EQUALITY caseIgnoreMatch
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.15
   )

  B.3.8 dateOfBirth

   (
           1.3.6.1.5.5.7.9.1
           NAME 'dateOfBirth'
           DESC 'Date of birth'
           EQUALITY generalizedTimeMatch
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.24
           SINGLE-VALUE
   )

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  B.3.9 placeOfBirth

   (
           1.3.6.1.5.5.7.9.2
           NAME 'placeOfBirth'
           DESC 'Place of birth'
           EQUALITY caseExactMatch
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.15
           SINGLE-VALUE
   )

  B.3.10 gender

   (
           1.3.6.1.5.5.7.9.3
           NAME 'gender'
           DESC 'Gender'
           EQUALITY caseIgnoreMatch
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.44
           SINGLE-VALUE
   )

  B.3.11 countryOfCitizenship

   (
           1.3.6.1.5.5.7.9.4
           NAME 'countryOfCitizenship'
           DESC 'Country of citizenship'
           EQUALITY caseIgnoreMatch
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.44
   )

  B.3.12 countryOfResidence

   (
           1.3.6.1.5.5.7.9.5
           NAME 'countryOfResidence'
           DESC 'Country of residence'
           EQUALITY caseIgnoreMatch
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.44
   )

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  B.3.13 pseudonym

   (
           2.5.4.65
           NAME 'pseudonym'
           DESC 'Pseudonym'
           EQUALITY caseExactMatch
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.15
   )

  B.3.14 contentType

   In the (highly unlikely) event of this attribute being stored in a
   Directory it is to be stored and requested in binary form, as
   contentType;binary.  Attribute values shall be OCTET STRINGs stored
   as binary (BER- or DER-encoded) data.

   (
           1.2.840.113549.1.9.3
           NAME 'contentType'
           DESC 'PKCS #7 content type attribute'
           EQUALITY objectIdentifierMatch
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.38
           SINGLE-VALUE
   )

  B.3.15 messageDigest

   In the (highly unlikely) event of this attribute being stored in a
   Directory it is to be stored and requested in binary form, as
   messageDigest;binary.  Attribute values shall be OCTET STRINGs stored
   as binary (BER- or DER-encoded) data.

   (
           1.2.840.113549.1.9.4
           NAME 'messageDigest'
           DESC 'PKCS #7 mesage digest attribute'
           EQUALITY octetStringMatch
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.5
           SINGLE-VALUE
   )

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  B.3.16 signingTime

   (
           1.2.840.113549.1.9.5
           NAME 'signingTime'
           DESC 'PKCS #7 signing time'
           EQUALITY signingTimeMatch
           SYNTAX 1.2.840.113549.1.9.26.2
           SINGLE-VALUE
   )

  B.3.17 counterSignature

   In the (highly unlikely) event that this attribute is to be stored in
   a directory, it is to be stored and requested in binary form, as
   counterSignature;binary.  Attribute values shall be stored as binary
   (BER- or DER-encoded) data.

   (
           1.2.840.113549.1.9.6
           NAME 'counterSignature'
           DESC 'PKCS #7 countersignature'
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.5
   )

  B.3.18 challengePassword

   (
           1.2.840.113549.1.9.7
           NAME 'challengePassword'
           DESC 'Challenge password for certificate revocations'
           EQUALITY caseExactMatch
           SYNTAX 1.3.6.1.4.1.1466.115.121.1.15
           SINGLE-VALUE
   )

   Note - It is not recommended to store unprotected values of this
   attribute in a directory.

 B.4 Matching rules

  B.4.1 pkcs9CaseIgnoreMatch

   (
           1.2.840.113549.1.9.27.1
           NAME 'pkcs9CaseIgnoreMatch'
           SYNTAX 1.2.840.113549.1.9.26.1
   )

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  B.4.2 signingTimeMatch

   (
           1.2.840.113549.1.9.27.3
           NAME 'signingTimeMatch'
           SYNTAX 1.2.840.113549.1.9.26.2
   )

C. Intellectual property considerations

   RSA Security makes no patent claims on the general constructions
   described in this document, although specific underlying techniques
   may be covered.

   License to copy this document is granted provided that it is
   identified as "RSA Security Inc.  Public-Key Cryptography Standards
   (PKCS)" in all material mentioning or referencing this document.

   RSA Security makes no representations regarding intellectual property
   claims by other parties.  Such determination is the responsibility of
   the user.

D. Revision history

   Version 1.0

      Version 1.0 was part of the June 3, 1991 initial public release of
      PKCS.  Version 1.0 was also published as NIST/OSI Implementors'
      Workshop document SEC-SIG-91-24.

      Version 1.1

      Version 1.1 incorporated several editorial changes, including
      updates to the references and the addition of a revision history.
      The following substantive changes were made:

      - Section 6: challengePassword, unstructuredAddress, and
        extendedCertificateAttributes attribute types were added
      - Section 7: challengePassword, unstructuredAddress, and
        extendedCertificateAttributes object identifiers were added

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   Version 2.0

   Version 2.0 incorporates several editorial changes as well.  In
   addition, the following substantive changes have been made:

      - Addition of a Section defining two new auxiliary object classes,
        pkcsEntity and naturalPerson
      - Addition of several new attribute types and matching rules for
        use in conjunction with these object classes and elsewhere
      - Update of all ASN.1 to be in line with the 1997 version of this
        syntax
      - Addition a "compilable" ASN.1 module
      - Addition, in accordance with [21], an ABNF description of all
        attributes and object classes
      - Addition of an intellectual property considerations section

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E. References

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

   [2]  Crocker, D. and P. Overell, "Augmented BNF for Syntax
        Specifications: ABNF", RFC 2234, November 1997.

   [3]  Housley, R., "Cryptographic Message Syntax CMS", RFC 2630, June
        1999.

   [4]  ISO/IEC 3166-1:Codes for the representation of names of
        countries and their subdivisions - Part 1: Country codes. 1997.

   [5]  ISO/IEC 8824-1:1999: Information technology - Abstract Syntax
        Notation One (ASN.1) - Specification of basic notation.1999.

   [6]  ISO/IEC 8825-1:1999: Information technology - ASN.1 Encoding
        Rules: Specification of Basic Encoding Rules (BER), Canonical
        Encoding Rules (CER) and Distinguished Encoding Rules (DER).
        1999.

   [7]  ISO/IEC 9594-2:1997: Information technology - Open Systems
        Interconnection - The Directory: Models. 1997.

   [8]  ISO/IEC 9594-6:1997: Information technology - Open Systems
        Interconnection - The Directory: Selected attribute types. 1997.

   [9]  ISO/IEC 9594-7:1997: Information technology - Open Systems
        Interconnection - The Directory: Selected object classes. 1997.

   [10] ISO/IEC 9594-8:1997: Information technology - Open Systems
        Interconnection - The Directory: Authentication framework. 1997.

   [11] ISO/IEC 10646-1: Information Technology - Universal Multiple-
        Octet Coded Character Set (UCS) - Part 1: Architecture and Basic
        Multilingual Plane. 1993.

   [12] Ramsdell, R., "S/MIME Version 3 Message Specification", RFC
        2633, June 1999.

   [13] RSA Laboratories. PKCS #6: Extended-Certificate Syntax Standard.
        Version 1.5, November 1993.

   [14] RSA Laboratories. PKCS #7: Cryptographic Message Syntax
        Standard. Version 1.5, November 1993.

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   [15] RSA Laboratories. PKCS #8: Private-Key Information Syntax
        Standard. Version 1.2, November 1993.

   [16] RSA Laboratories. PKCS #10: Certification Request Syntax
        Standard. Version 1.0, November 1993.

   [17] RSA Laboratories. PKCS #12: Personal Information Exchange Syntax
        Standard. Version 1.0, June 1999.

   [18] RSA Laboratories. PKCS #15: Cryptographic Token Information
        Format Standard. Version 1.1, June 2000.

   [19] Santesson, S., Polk, W., Barzin, P. and M. Nystrom, "Internet
        X.509 Public Key Infrastructure - Qualified Certificates
        Profile", Work in Progress.

   [20] Smith, M. "Definition of the inetOrgPerson LDAP Object Class",
        RFC 2798, April 2000.

   [21] Wahl, M., Coulbeck, A., Howes, T. and S. Kille, "Lightweight
        Directory Access Protocol (v3): Attribute Syntax Definitions",
        RFC 2252, December 1997.

   [22] Wahl, M., Howes, T. and S. Kille, "Lightweight Directory Access
        Protocol (v3)", RFC 2251, December 1997.

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F. Contact information & About PKCS

   The Public-Key Cryptography Standards are specifications produced by
   RSA Laboratories in cooperation with secure systems developers
   worldwide for the purpose of accelerating the deployment of public-
   key cryptography.  First published in 1991 as a result of meetings
   with a small group of early adopters of public-key technology, the
   PKCS documents have become widely referenced and implemented.
   Contributions from the PKCS series have become part of many formal
   and de facto standards, including ANSI X9 documents, PKIX, SET,
   S/MIME, and SSL.

   Further development of PKCS occurs through mailing list discussions
   and occasional workshops, and suggestions for improvement are
   welcome.  For more information, contact:

   PKCS Editor
   RSA Laboratories
   20 Crosby Drive
   Bedford, MA  01730 USA
   pkcs-editor@rsasecurity.com
   http://www.rsasecurity.com/rsalabs/PKCS

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Full Copyright Statement

   Copyright (C) The Internet Society (2000).  All Rights Reserved.

   This document and translations of it may be copied and furnished to
   others provided that the above copyright notice and this paragraph
   are included on all such copies.  However, this document itself may
   not be modified in any way, such as by removing the copyright notice
   or references to the Internet Society or other Internet
   organizations, except as required to translate it into languages
   other than English.

   The limited permissions granted above are perpetual and will not be
   revoked by the Internet Society or its successors or assigns.

   This document and the information contained herein is provided on an
   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR  IMPLIED, INCLUDING
   BUT NOT  LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY  IMPLIED WARRANTIES OF
   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Acknowledgement

   Funding for the RFC Editor function is currently provided by the
   Internet Society.

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