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Network Working Group                                            M. Wahl
INTERNET-DRAFT                                       Critical Angle Inc.
Obsoletes: RFC 1778                                          A. Coulbeck
                                                           Isode Limited
                                                                T. Howes
                                           Netscape Communications Corp.
                                                                S. Kille
                                                           Isode Limited
Intended Category: Standards Track                         24 March 1997


                  Lightweight Directory Access Protocol (v3):
                       Attribute Syntax Definitions
                 <draft-ietf-asid-ldapv3-attributes-04.txt>

1. 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 learn the current status of any Internet-Draft, please check the
   "1id-abstracts.txt" listing  contained in the Internet-Drafts Shadow
   Directories on ds.internic.net (US East Coast), nic.nordu.net (Europe),
   ftp.isi.edu (US West Coast), or munnari.oz.au (Pacific Rim).

2. Abstract

   The Lightweight Directory Access Protocol (LDAP) [1] requires that the
   contents of AttributeValue fields in protocol elements be octet
   strings.  This document defines a set of syntaxes for LDAPv3, and the
   rules by which attribute values of these syntaxes are represented as
   octet strings for transmission in the LDAP protocol.  The syntaxes
   defined in this document are referenced by this and other documents that
   define attribute types.  This document also defines the set of attribute
   types which LDAP servers should support.

3. Overview

   Section 4 states the general requirements and notations for attribute
   types, object classes, syntax and matching rule definitions.

   Section 5 lists attributes, section 6 syntaxes and section 7 object
   classes.

4. General Issues

   This document describes encodings used in an Internet protocol. Terms are
   defined in [4].



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4.1. Attribute Types

   The attribute types are described by sample values for the subschema
   "attributeTypes" attribute, which is written in the
   AttributeTypeDescription syntax.  While lines have been folded for
   readability, the values transferred in protocol would not contain
   newlines.

   The AttributeTypeDescription is encoded according to the following BNF,
   and the productions for <oid>, <DirectoryStrings> and <DirectoryString>
   are given in sections 4.2.1.

      <AttributeTypeDescription> ::= "("
          <oid>   -- AttributeType identifier
          [ "NAME" <DirectoryStrings> ] -- name used in AttributeType
          [ "DESC" <DirectoryString> ]
          [ "OBSOLETE" ]
          [ "SUP" <oid> ]         -- derived from this other AttributeType
          [ "EQUALITY" <oid> ]    -- Matching Rule name
          [ "ORDERING" <oid> ]    -- Matching Rule name
          [ "SUBSTR" <oid> ]      -- Matching Rule name
          [ "SYNTAX" <DirectoryString> ] -- see section 4.2
          [ "SINGLE-VALUE" ]              -- default multi-valued
          [ "COLLECTIVE" ]                -- default not collective
          [ "NO-USER-MODIFICATION" ]      -- default user modifiable
          [ "USAGE" <AttributeUsage> ]    -- default user applications
          ")"

      <AttributeUsage> ::=
          "userApplications"
      |   "directoryOperation"
      |   "distributedOperation"  -- DSA-shared
      |   "dSAOperation"          -- DSA-specific, value depends on server

   Servers are not required to provide the same or any text
   in the description part of the subschema values they maintain.

   Servers SHOULD implement all the attribute types referenced in section 5:
   they MUST be able to perform equality matching of values, but need not
   perform any additional validity checks on attribute values.

   Servers MAY recognize additional names and attributes not listed in this
   document, and if they do so, SHOULD publish the definitions of the types
   in the attributeTypes attribute of their subschema subentries.

   AttributeDescriptions can be used as the value in a NAME part of an
   AttributeTypeDescription.  Note that these are case insensitive.

4.2. Syntaxes

   This section defines general requirements for LDAP attribute value
   syntax encodings. All documents defining attribute syntax encodings for
   use with LDAP are expected to conform to these requirements.



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   The encoding rules defined for a given attribute syntax must produce
   octet strings.  To the greatest extent possible, encoded octet
   strings should be usable in their native encoded form for display
   purposes. In particular, encoding rules for attribute syntaxes
   defining non-binary values should produce strings that can be
   displayed with little or no translation by clients implementing
   LDAP.  There are a few cases (e.g. Audio) however, when it is not sensible
   to produce a printable representation, and clients MUST NOT assume that
   an unrecognized syntax is a string representation.

4.2.1. Common Encoding Aspects

   In these encodings where an arbitrary string is used as part of a larger
   production (other than a Distinguished Name), a backslash quoting mechanism
   is used to encode the following separator symbol character (such as ''',
   '$' or '#') if it should occur in that string.  The backslash is followed
   by a pair of hexadecimal digits representing the next character.  A
   backslash itself in the string which forms part of a larger syntax is
   always transmitted as '\5C' or '\5c'.

   For the purposes of defining the encoding rules for attribute syntaxes,
   the following auxiliary BNF definitions will be used:

     <a> ::= 'a' | 'b' | 'c' | 'd' | 'e' | 'f' | 'g' | 'h' | 'i' |
             'j' | 'k' | 'l' | 'm' | 'n' | 'o' | 'p' | 'q' | 'r' |
             's' | 't' | 'u' | 'v' | 'w' | 'x' | 'y' | 'z' | 'A' |
             'B' | 'C' | 'D' | 'E' | 'F' | 'G' | 'H' | 'I' | 'J' |
             'K' | 'L' | 'M' | 'N' | 'O' | 'P' | 'Q' | 'R' | 'S' |
             'T' | 'U' | 'V' | 'W' | 'X' | 'Y' | 'Z'

     <d> ::= '0' | '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9'

     <hex-digit> ::= <d> | 'a' | 'b' | 'c' | 'd' | 'e' | 'f' |
                      'A' | 'B' | 'C' | 'D' | 'E' | 'F'

     <k> ::= <a> | <d> | '-'

     <p> ::= <a> | <d> | ''' | '(' | ')' | '+' | ',' | '-' | '.' |
             '/' | ':' | '?' | ' '

     <letterstring> ::= <a> | <a> <letterstring>

     <numericstring> ::= <d> | <d> <numericstring>

     <keystring> ::= <a> | <a> <anhstring>

     <anhstring> ::= <k> | <k> <anhstring>

     <printablestring> ::= <p> | <p> <printablestring>

     <space> ::= ' ' | ' ' <space>

     <whsp> ::= <space> | empty



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     <utf8> ::= any sequence of octets formed from the UTF-8 [9]
                transformation of a character from ISO 10646 [10]

     <dstring> ::= <utf8> | <utf8> <dstring>

     <DirectoryStrings> ::= <DirectoryString> | '(' <DirectoryStringList> ')'

     <DirectoryStringList> ::= <DirectoryStringList> <DirectoryString> | ""

     <DirectoryString> ::= ''' <dstring> '''

     <oids> ::= <oid> | '(' <oidlist> ')'

     <oidlist> ::= <oidlist> '$' <oid> | <oid>

4.2.2  Binary Transfer of Values

   This encoding format is used if the binary encoding is requested by the
   client for an attribute, or if the attribute syntax name is 'Binary'.  The
   value, an instance of the ASN.1 AttributeValue type, is BER-encoded,
   subject to the restrictions of section 5.1 of [1], and this sequence of
   octets is used as the value.

   All servers MUST implement this form for both generating attribute values in
   search responses, and parsing attribute values in add, compare and modify
   requests, if the attribute type is recognized and the attribute syntax name
   is 'Binary'.  Clients MUST be prepared receiving values in binary (e.g.
   userCertificate or audio), and MUST NOT simply display binary or
   unrecognized values to users.

4.2.3. Syntax Names

   Names of syntaxes for use with LDAP are ASCII strings which either
   begin with a letter and contain only letters or digits.  The names are
   case insensitive.  Historically since syntaxes correspond to ASN.1 types,
   they have been named starting with a capital letter.  A suggested minimum
   upper bound on the number of characters in value with a DirectoryString or
   IA5String syntax or the number of bytes in a value for all other syntaxes
   may be indicated by appending this bound count inside of curly braces.
   For instance, "DirectoryString{64}" suggests that server implementations
   should allow the string to be 64 characters long, althoough they may allow
   longer strings.  Note that a single character of the DirectoryString may be
   encoded in more than one byte since UTF-8 is a variable-length encoding.

   Syntax names do not have global scope: two clients or servers may
   know of different syntaxes with the same name.

   The definition of additional arbitrary syntaxes is strongly depreciated
   since it will hinder interoperability: today's client and server
   implementations generally do not have the ability to dynamically recognize
   new syntaxes.  In most cases attributes will be defined with the
   DirectoryString syntax.




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4.3. Object Classes

   Object class descriptions are written according to the following BNF:

      <ObjectClassDescription> ::= "("
          <oid>   -- ObjectClass identifier
          [ "NAME" <DirectoryStrings> ]
          [ "DESC" <DirectoryString> ]
          [ "OBSOLETE" ]
          [ "SUP" <oids> ]    -- Superior ObjectClasses
          [ ( "ABSTRACT" | "STRUCTURAL" | "AUXILIARY" ) ] -- default structural
          [ "MUST" <oids> ]   -- AttributeTypes
          [ "MAY" <oids> ]    -- AttributeTypes
      ")"

   These are described as sample values for the subschema "objectClasses"
   attribute for a server which implements the LDAP schema.
   While lines have been folded for readability, the values transferred in
   protocol would not contain newlines.

   Servers SHOULD implement all the object classes referenced in section 7,
   except for extensibleObject, which is optional.

   Servers MAY implement additional object classes not listed in this
   document, and if they do so, SHOULD publish the definitions of the classes
   in the objectClasses attribute of their subschema subentries.  Later
   documents may define additional object classes.

4.4. Matching Rules

   Matching rules are used by servers to compare attribute values against
   assertion values when performing Search and Compare operations.

   Most of the attributes given in this document will have an equality
   matching rule defined.

   Matching rule descriptions are written according to the following BNF:

      <MatchingRuleDescription> ::= "("
          <oid>   -- MatchingRule identifier
          [ "NAME" <DirectoryStrings> ]
          [ "DESC" <DirectoryString> ]
          [ "OBSOLETE" ]
          "SYNTAX" <DirectoryString>
         ")"

   Servers SHOULD implement all the matching rules in section 8.

   Servers MAY implement additional matching rules not listed in this
   document, and if they do so, SHOULD publish the definitions of the
   matching rules in the matchingRules attribute of their
   subschema subentries.




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5. Attribute Types

   All LDAP server implementations MUST recognize the attribute types
   defined in this section.  These types are based on definitions in
   X.501(93) [3].

   Servers SHOULD also recognize all the attributes from section 5 of [12],
   from section 5 of [13].

5.1. Standard Operational Attributes

5.1.1. createTimestamp

    ( 2.5.18.1 NAME 'createTimestamp' EQUALITY generalizedTimeMatch
      ORDERING generalizedTimeOrderingMatch SYNTAX 'GeneralizedTime'
      SINGLE-VALUE NO-USER-MODIFICATION USAGE directoryOperation )

5.1.2. modifyTimestamp

    ( 2.5.18.2 NAME 'modifyTimestamp' EQUALITY generalizedTimeMatch
      ORDERING generalizedTimeOrderingMatch SYNTAX 'GeneralizedTime'
      SINGLE-VALUE NO-USER-MODIFICATION USAGE directoryOperation )

5.1.3. creatorsName

    ( 2.5.18.3 NAME 'creatorsName' EQUALITY distinguishedNameMatch SYNTAX 'DN'
      SINGLE-VALUE NO-USER-MODIFICATION USAGE directoryOperation )

5.1.4. modifiersName

    ( 2.5.18.4 NAME 'modifiersName' EQUALITY distinguishedNameMatch SYNTAX 'DN'
      SINGLE-VALUE NO-USER-MODIFICATION USAGE directoryOperation )

5.1.5. subschemaSubentry

    The value of this attribute is the name of a subschema subentry, an
    entry in which the server makes available attributes specifying
    the schema.

    ( 2.5.18.10 NAME 'subschemaSubentry'
      EQUALITY distinguishedNameMatch SYNTAX 'DN' NO-USER-MODIFICATION
      SINGLE-VALUE USAGE directoryOperation )

5.1.6. attributeTypes

    ( 2.5.21.5 NAME 'attributeTypes'
      EQUALITY objectIdentifierFirstComponentMatch
      SYNTAX 'AttributeTypeDescription' USAGE directoryOperation )

5.1.7. objectClasses

    ( 2.5.21.6 NAME 'objectClasses'
      EQUALITY objectIdentifierFirstComponentMatch
      SYNTAX 'ObjectClassDescription' USAGE directoryOperation )


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5.2. LDAP Operational Attributes

   These attributes are only present in the root DSE.

   Servers MUST recognize these attribute names, but it is not required that
   a server provide values for these attributes, when the attribute
   corresponds to a feature which the server does not implement.

5.2.1. namingContexts

   The values of this attribute correspond to naming contexts which this
   server masters or shadows.  If the server does not master any
   information (e.g. it is an LDAP gateway to a public X.500 directory)
   this attribute will be absent.  If the server believes it contains the
   entire directory, the attribute will have a single value, and that
   value will be the empty string (indicating the null DN of the root).
   This attribute will allow a client to choose suitable base objects
   for searching when it has contacted a server.

    ( 1.3.6.1.4.1.1466.101.120.5 NAME 'namingContexts'
     SYNTAX 'DN' USAGE dSAOperation )

5.2.2. altServer

   The values of this attribute are URLs of other servers which may be
   contacted when this server becomes unavailable.  If the server does not
   know of any other servers which could be used this attribute will be
   absent. Clients may cache this information in case their preferred LDAP
   server later becomes unavailable.

    ( 1.3.6.1.4.1.1466.101.120.6 NAME 'altServer'
     SYNTAX 'IA5String' USAGE dSAOperation )

5.2.3. supportedExtension

   The values of this attribute are OBJECT IDENTIFIERs identifying the
   supported extended operations which the server supports.

   If the server does not support any extensions this attribute will be
   absent.

    ( 1.3.6.1.4.1.1466.101.120.7 NAME 'supportedExtension'
     SYNTAX 'OID' USAGE dSAOperation )

5.2.4. supportedControl

   The values of this attribute are the OBJECT IDENTIFIERS identifying
   controls which the server supports.  If the server does not
   support any controls, this attribute will be absent.

    ( 1.3.6.1.4.1.1466.101.120.13 NAME 'supportedControl'
     SYNTAX 'OID' USAGE dSAOperation )




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5.2.5. supportedSASLMechanisms

   The values of this attribute are the names of supported SASL
   mechanisms which the server supports.  If the server does not
   support any mechanisms this attribute will be absent.

    ( 1.3.6.1.4.1.1466.101.120.14 NAME 'supportedSASLMechanisms'
     SYNTAX 'LDAPString' USAGE dSAOperation )

5.2.6. supportedLDAPVersion

   The values of this attribute are the versions of the LDAP protocol which
   the server implements.

    ( 1.3.6.1.4.1.1466.101.120.15 NAME 'supportedLDAPVersion'
     SYNTAX 'INTEGER' USAGE dSAOperation )

6. Syntaxes

   Servers SHOULD recognize all the syntaxes described in this section
   (6.1 - 6.3).

6.1. AttributeTypeDescription

   Values with this syntax are encoded according to the BNF given at the
   start of section 4.1. For example,

        ( 2.5.4.0 NAME 'objectClass' SYNTAX 'OID' )

6.2. Audio

   The encoding of a value with Audio syntax is the octets of the value
   itself, an 8KHz uncompressed encoding compatible with the SunOS
   4.1.3 'play' utility.

6.3. BitString

   The encoding of a value with BitString syntax is according to the
   following BNF:

      <bitstring> ::= ''' <binary-digits> ''B'

      <binary-digits> ::= '0' <binary-digits> | '1' <binary-digits> |
      empty

   Example:

        '0101111101'B








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6.4. Boolean

   Values with Boolean syntax are encoded according to the following
   BNF:

      <boolean> ::= "TRUE" | "FALSE"

   Boolean values have an encoding of "TRUE" if they are logically true,
   and have an encoding of "FALSE" otherwise.

6.5. Certificate

   Because of the changes from X.509(1988) and X.509(1993) and additional
   changes to the ASN.1 definition to support certificate extensions, no
   string representation is defined, and values with Certificate syntax
   MUST only be transferred using the binary encoding, by requesting or
   returning the attributes with descriptions "userCertificate;binary" or
   "caCertificate;binary".  The BNF notation in RFC 1778 for
   "User Certificate" is not recommended to be used.

6.6. CertificateList

   Because of the incompatibility of the X.509(1988) and X.509(1993)
   definitions of revocation lists, values with CertificateList syntax
   MUST only be transferred using a binary encoding, by requesting or
   returning the attributes with descriptions
   "certificateRevocationList;binary" or "authorityRevocationList;binary".
   The BNF notation in RFC 1778 for "Authority Revocation List" is not
   recommended to be used.

6.7. CertificatePair

   Because the Certificate is being carried in binary, values with
   CertificatePair syntax MUST only be transferred using a binary encoding,
   by requesting or returning the attribute description
   "crossCertificatePair;binary".  The BNF notation in RFC 1778 for
   "Certificate Pair" is not recommended to be used.

6.8. CountryString

   A value of CountryString syntax is encoded the same as a value of
   DirectoryString syntax.  Note that this syntax is limited to values of
   exactly two printable string characters.

      <CountryString>  ::= <p> <p>

   Example:
      US








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6.9. DN

   Values with DN (Distinguished Name) syntax are encoded to have the
   representation defined in [5].  Note that this representation is not
   reversible to an ASN.1 encoding used in X.500 for Distinguished Names, as
   the CHOICE of any DirectoryString element in an RDN is no longer known.

   Examples (from [5]):
      CN=Steve Kille,O=Isode Limited,C=GB
      OU=Sales+CN=J. Smith,O=Widget Inc.,C=US
      CN=L. Eagle,O=Sue\, Grabbit and Runn,C=GB
      CN=Before\0DAfter,O=Test,C=GB
      1.3.6.1.4.1.1466.0=#04024869,O=Test,C=GB
      SN=Lu\C4\8Di\C4\C7

6.10. DirectoryString

   A string with DirectoryString syntax is encoded in the UTF-8 form of
   ISO 10646 (a superset of Unicode).  Servers and clients MUST be prepared to
   receive encodings of arbitrary Unicode characters, including characters
   not presently assigned to any character set, in values.

   For characters in the PrintableString form, the value is encoded as the
   string value itself.

   If it is of the TeletexString form, then the characters are transliterated
   to their equivalents in UniversalString, and encoded in UTF-8 [9].

   If it is of the UniversalString or BMPString forms [10], UTF-8 is used to
   encode them.

   Note: the form of DirectoryString is not indicated in protocol unless the
   attribute value is carried in binary.  Servers which convert to DAP MUST
   choose an appropriate form.  Servers MUST NOT reject values merely because
   they contain legal Unicode characters outside of the range of printable
   ASCII.

   Example:

      This is a string of DirectoryString containing #!%#@

6.11. DITContentRuleDescription

   Values with this syntax are encoded according to the following BNF:

      <DITContentRuleDescription> ::= "("
          <oid>   -- Structural ObjectClass identifier
          [ "NAME" <DirectoryStrings> ]
          [ "DESC" <DirectoryString> ]
          [ "OBSOLETE" ]
          [ "AUX" <oids> ]    -- Auxiliary ObjectClasses
          [ "MUST" <oids> ]   -- AttributeType identifiers
          [ "MAY" <oids> ]    -- AttributeType identifiers
          [ "NOT" <oids> ]    -- AttributeType identifiers
         ")"

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6.12. FacsimileTelephoneNumber

   Values with the FacsimileTelephoneNumber syntax are encoded according
   to the following BNF:

      <fax-number> ::= <printablestring> [ '$' <faxparameters> ]

      <faxparameters> ::= <faxparm> | <faxparm> '$' <faxparameters>

      <faxparm> ::= 'twoDimensional' | 'fineResolution' | 'unlimitedLength' |
                   'b4Length' | 'a3Width' | 'b4Width' | 'uncompressed'

   In the above, the first <printablestring> is the actual fax number,
   and the <faxparm> tokens represent fax parameters.

6.13. Fax

   Values with Fax syntax are encoded as if they were octet strings
   containing Group 3 Fax images as defined in [7].

6.14. GeneralizedTime

   Values of this syntax are encoded as printable strings, represented
   as specified in X.208.  Note that the time zone must be specified.
   It is strongly recommended that Zulu time zone be used.  For example,

                199412161032Z

6.15. IA5String

   The encoding of a value with IA5String syntax is the string value
   itself.

6.16. INTEGER

   Values with INTEGER syntax are encoded as the decimal representation
   of their values, with each decimal digit represented by the its
   character equivalent. So the number 1321 is represented by the character
   string "1321".

6.17. JPEG

   Values with JPEG syntax are encoded as if they were octet strings
   containing JPEG images in the JPEG File Interchange Format (JFIF), as
   described in [8].











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6.18. MatchingRuleUseDescription

   Values of this syntax are encoded according to the following BNF:

      <MatchingRuleUseDescription> ::= "("
          <oid>   -- MatchingRule identifier
          [ "NAME" <DirectoryStrings> ]
          [ "DESC" <DirectoryString> ]
          [ "OBSOLETE" ]
         "APPLIES" <oids>    -- AttributeType identifiers
         ")"

6.19. MHSORAddress

   Values of type MHSORAddress are encoded as strings, according to
   the format defined in [11].

6.20. NameAndOptionalUID

   The encoding of a value with the NameAndOptionalUID syntax is according
   to the following BNF:

      <NameAndOptionalUID> ::=
                <DistinguishedName> [ '#' <bitstring> ]

   Although the '#' character may occur in a string representation of a
   distinguished name, no additional special quoting is done.

   This syntax has been added subsequent to RFC 1778.

   Example:

      1.3.6.1.4.1.1466.0=#04024869,O=Test,C=GB#'0101'B

6.21. NameFormDescription

   Values of this syntax are encoded according to the following BNF:

      <NameFormDescription> ::= "("
          <oid>   -- NameForm identifier
          [ "NAME" <DirectoryStrings> ]
          [ "DESC" <DirectoryString> ]
          [ "OBSOLETE" ]
          "OC" <oid>          -- Structural ObjectClass
          "MUST" <oids>       -- AttributeTypes
          [ "MAY" <oids> ]    -- AttributeTypes
      ")"









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6.22. NumericString

   The encoding of a string with the NumericString syntax is the string
   value itself. Example:

      1997


6.23. ObjectClassDescription

   Values of this syntax are encoded according to the BNF in section 4.3.

6.24. OID

   Values with OID (Object Identifier) syntax are encoded according to the
   following BNF:

      <oid> ::= <descr> | <numericoid>

      <descr> ::= <keystring>

      <numericoid> ::= <numericstring> | <numericstring> '.' <numericoid>

   In the above BNF, <descr> is the syntactic representation of an
   object descriptor, which consists of letters and digits, starting
   with a letter. When encoding values with OID syntax, the first encoding
   option MUST be used in preference to the second. That is, in encoding
   object identifiers, object descriptors (where assigned and known by
   the implementation) must be used in preference to numeric oids to
   the greatest extent possible. All permitted object descriptors for use
   in LDAP are given in this document.  No other object descriptors may be
   used.  (Note that clients should expect that LDAPv2 implementations
   will return object descriptors other than those listed.)

   Example:

       1.2.3.4
       cn

6.25. OtherMailbox

   Values of the OtherMailbox syntax are encoded according to the
   following BNF:

      <otherMailbox> ::= <mailbox-type> '$' <mailbox>

      <mailbox-type> ::= an encoded Printable String

      <mailbox> ::= an encoded IA5 String

   In the above, <mailbox-type> represents the type of mail system in
   which the mailbox resides, for example "MCIMail"; and <mailbox> is the
   actual mailbox in the mail system defined by <mailbox-type>.



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6.26. Password

   Values with Password syntax are encoded as octet strings.

   Example:

      secret

6.27. PostalAddress

   Values with the PostalAddress syntax are encoded according to the
   following BNF:

      <postal-address> ::= <dstring> | <dstring> '$' <postal-address>

   In the above, each <dstring> component of a postal address value is
   encoded as a value of type DirectoryString syntax.  Backslashes and
   dollar characters, if they occur in the component, are quoted as
   described in section 4.2.

   Example:

      1234 Main St.$Anytown, CA 12345$USA
      \241,000,000 Sweepstakes$PO Box 1000000$Anytown, CA 12345$USA

6.28. PresentationAddress

   Values with the PresentationAddress syntax are encoded to have the
   representation described in [6].

6.29. PrintableString

   The encoding of a value with PrintableString syntax is the string
   value itself.  PrintableString is limited to the characters in
   production <p> of section 4.1.

   Example:

      This is a PrintableString

6.30. TelephoneNumber

   Values with the TelephoneNumber syntax are encoded as if they were
   Printable String types.  Telephone numbers are recommended in X.520 to
   be in international form.

   Example:

      +1 512 305 0280

6.31. UTCTime

   Values with UTCTime syntax are encoded as if they were printable
   strings with the strings containing a UTCTime value.  This is historical;
   new attribute definitions will use GeneralizedTime instead.

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7. Object Classes

   Servers SHOULD recognize all the names of standard classes from section
   7 of [12], as well as the names of the Internet classes from section
   7 of [13].

7.1. Extensible Object Class

   The extensibleObject object class, if present in an entry, permits that
   entry to optionally hold any attribute.  The MAY attribute list of this
   class is implicitly the set of all attributes known to the server.

    ( 1.3.6.1.4.1.1466.101.120.111 NAME 'extensibleObject'
      SUP top AUXILIARY )

   The mandatory attributes of the other object classes of this entry are
   still required to be present.

   Note that not all servers will implement this object class, and those
   which do not will reject requests to add entries which contain this
   object class, or modify an entry to add this object class.

8. Matching Rules

   Servers which implement extensibleMatch SHOULD recognize the following
   matching rules, used for equality matching, and be capable of
   performing the matching rules.  For all these rules, the
   assertion syntax is the same as the value syntax.

    ( 2.5.13.0 NAME 'objectIdentifierMatch' SYNTAX 'OID' )
    ( 2.5.13.1 NAME 'distinguishedNameMatch' SYNTAX 'DN' )
    ( 2.5.13.2 NAME 'caseIgnoreMatch' SYNTAX 'DirectoryString' )
    ( 2.5.13.8 NAME 'numericStringMatch' SYNTAX 'NumericString' )
    ( 2.5.13.11 NAME 'caseIgnoreListMatch' SYNTAX 'PostalAddress' )
    ( 2.5.13.14 NAME 'integerMatch' SYNTAX 'INTEGER' )
    ( 2.5.13.16 NAME 'bitStringMatch' SYNTAX 'BitString' )
    ( 2.5.13.17 NAME 'octetStringMatch' SYNTAX 'Password' )
    ( 2.5.13.20 NAME 'telephoneNumberMatch' SYNTAX 'TelephoneNumber' )
    ( 2.5.13.22 NAME 'presentationAddressMatch' SYNTAX 'PresentationAddress' )
    ( 2.5.13.23 NAME 'uniqueMemberMatch' SYNTAX 'NameAndOptionalUID' )
    ( 2.5.13.24 NAME 'protocolInformationMatch' SYNTAX 'ProtocolInformation' )
    ( 2.5.13.27 NAME 'generalizedTimeMatch' SYNTAX 'GeneralizedTime' )
    ( 1.3.6.1.4.1.1466.109.114.1 NAME 'caseExactIA5Match' SYNTAX 'IA5String' )
    ( 1.3.6.1.4.1.1466.109.114.2 NAME 'caseIgnoreIA5Match' SYNTAX 'IA5String' )

   When performing the caseIgnoreMatch, caseIgnoreListMatch,
   telephoneNumberMatch, caseExactIA5Match and caseIgnoreIA5Match,
   multiple adjoining whitespace characters are treated the same as an
   individual space, and leading and trailing whitespace is ignored.

9. Security Considerations

   Security issues are not discussed in this memo.



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10. Acknowledgements

   This document is based substantially on RFC 1778, written by Tim Howes,
   Steve Kille, Wengyik Yeong and Colin Robbins.

   Many of the attribute syntax encodings defined in this document are
   adapted from those used in the QUIPU and the IC R3 X.500
   implementations. The contributions of the authors of both these
   implementations in the specification of syntaxes in this document are
   gratefully acknowledged.

11. Authors Addresses

       Mark Wahl
       Critical Angle Inc.
       4815 West Braker Lane #502-385
       Austin, TX 78759
       USA

       EMail:  M.Wahl@critical-angle.com


       Andy Coulbeck
       Isode Limited
       The Dome, The Square
       Richmond  TW9 1DT
       United Kingdom

       Phone:  +44 181-332-9091
       EMail:  A.Coulbeck@isode.com

       Tim Howes
       Netscape Communications Corp.
       501 E. Middlefield Rd
       Mountain View, CA 94043
       USA

       Phone:  +1 415 254-1900
       EMail:   howes@netscape.com


       Steve Kille
       Isode Limited
       The Dome, The Square
       Richmond
       TW9 1DT
       UK

       Phone:  +44-181-332-9091
       EMail:  S.Kille@isode.com






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12. Bibliography

   [1] M. Wahl, T. Howes, S. Kille, "Lightweight Directory Access Protocol
       (Version 3)", INTERNET-DRAFT <draft-ietf-asid-ldapv3-protocol-04.txt>,
       March 1997.

   [2] The Directory: Selected Attribute Types.  ITU-T Recommendation
       X.520, 1993.

   [3] The Directory: Models. ITU-T Recommendation X.501, 1993.

   [4] S. Bradner, "Key words for use in RFCs to Indicate Requirement
       Levels", INTERNET-DRAFT <draft-bradner-key-words-03.txt>.

   [5] M. Wahl, S. Kille, "A UTF-8 String Representation of Distinguished
       Names", INTERNET-DRAFT <draft-ietf-asid-ldapv3-dn-02.txt>,
       March 1997.

   [6] S. Kille, "A String Representation for Presentation Addresses",
       RFC 1278, University College London, November 1991.

   [7] Terminal Equipment and Protocols for Telematic Services -
       Standardization of Group 3 facsimile apparatus for document
       transmission.  CCITT, Recommendation T.4.

   [8] JPEG File Interchange Format (Version 1.02).  Eric Hamilton,
       C-Cube Microsystems, Milpitas, CA, September 1, 1992.

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

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

   [11] H. Alvestrand, S. Kille, R. Miles, M. Rose, S. Thompson,
        "Mapping between X.400 and RFC-822 Message Bodies", RFC 1495,
        August 1993.

   [12] M. Wahl, "X.500(93) User Schema for use with LDAP",
        INTERNET-DRAFT <draft-ietf-asid-ldapv3schema-x500-00.txt>,
        March 1997.

   [13] M. Wahl, "Pilot Internet Schema for use with LDAP",
        INTERNET-DRAFT <draft-ietf-asid-ldapv3schema-pilot-00.txt>,
        March 1997.









<draft-ietf-asid-ldapv3-attributes-04.txt>
Expires: September 1997
Wahl, Coulbeck, Howes, Kille                                   Page 17


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