INTERNET-DRAFT Kurt D. Zeilenga
Intended Category: BCP OpenLDAP Foundation
Expires in six months 20 June 2003 Obsoletes:
RFC 3383
IANA Considerations for LDAP
<draft-ietf-ldapbis-bcp64-00.txt>
Status of Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
This document is intended to be, after appropriate review and
revision, submitted to the RFC Editor as a Best Current Practice
document. Distribution of this memo is unlimited. Technical
discussion of this document will take place on the IETF LDAP Revision
Working Group (LDAPBIS) mailing list <ietf-ldapbis@openldap.org>.
Please send editorial comments directly to the document editor
<Kurt@OpenLDAP.org>.
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.''
The list of current Internet-Drafts can be accessed at
<http://www.ietf.org/ietf/1id-abstracts.txt>. The list of
Internet-Draft Shadow Directories can be accessed at
<http://www.ietf.org/shadow.html>.
Copyright (C) The Internet Society (2003). All Rights Reserved.
Please see the Full Copyright section near the end of this document
for more information.
Abstract
This document provides procedures for registering extensible elements
of Lightweight Directory Access Protocol (LDAP). The document also
provides guidelines to Internet Assigned Numbers Authority (IANA)
Zeilenga IANA Considerations for LDAP [Page 1]
INTERNET-DRAFT draft-ietf-ldapbis-bcp64-00.txt 20 June 2003
describing conditions under which new values can be assigned.
1. Introduction
The Lightweight Directory Access Protocol [Roadmap] (LDAP) is an
extensible protocol. LDAP supports:
- addition of new operations,
- extension of existing operations, and
- extensible schema.
This document details procedures for registering values of used to
unambiguously identify extensible elements of the protocol including:
- LDAP message types;
- LDAP extended operations and controls;
- LDAP result codes;
- LDAP authentication methods;
- LDAP attribute description options; and
- Object Identifier descriptors.
These registries are maintained by the Internet Assigned Numbers
Authority (IANA).
In addition, this document provides guidelines to IANA describing the
conditions under which new values can be assigned.
This document replaces RFC 3383.
2. Terminology and Conventions
This section details terms and conventions used in this document.
2.1. Policy Terminology
The terms "IESG Approval", "Standards Action", "IETF Consensus",
"Specification Required", "First Come First Served", "Expert Review",
and "Private Use" are used as defined in BCP 26 [RFC2434].
2.2. Requirement Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in BCP 14 [RFC2119]. In
Zeilenga IANA Considerations for LDAP [Page 2]
INTERNET-DRAFT draft-ietf-ldapbis-bcp64-00.txt 20 June 2003
this case, "the specification" as used by BCP 14 refers to the
processing of protocols being submitted to the IETF standards
process.
2.3. Common ABNF Productions
A number of syntaxes in this document are described using ABNF
[RFC2234]. These syntaxes rely on the following common productions:
ALPHA = %x41-5A / %x61-7A ; A-Z / a-z
LDIGIT = %x31-39 ; 1-9
DIGIT = %x30 / LDIGIT ; 0-9
HYPHEN = %x2D ; "-"
DOT = %x2E ; "."
number = DIGIT / ( LDIGIT 1*DIGIT )
keychar = ALPHA / DIGIT / HYPHEN
leadkeychar = ALPHA
keystring = leadkeychar *keychar
A keyword is a case-insensitive string of UTF-8 [UTF-8] encoded
characters from the Universal Character Set (UCS) [ISO10646]
restricted to the <keystring> production.
3. IANA Considerations for LDAP
This section details each kind of protocol value which can be
registered and provides IANA guidelines on how to assign new values.
IANA may reject obviously bogus registrations described.
3.1. Object Identifiers
Numerous LDAP schema and protocol elements are identified by Object
Identifiers (OIDs). Specifications which assign OIDs to elements
SHOULD state who delegated the OIDs for its use.
For IETF developed elements, specifications SHOULD use OIDs under
Zeilenga IANA Considerations for LDAP [Page 3]
INTERNET-DRAFT draft-ietf-ldapbis-bcp64-00.txt 20 June 2003
"Internet Directory Numbers" (1.3.6.1.1.x). Numbers under this OID
arc will be assigned upon Expert Review with Specification Required.
Only one OID per specification will be assigned. The specification
MAY then assign any number of OIDs within this arc without further
coordination with IANA.
For elements developed by others, any properly delegated OID can be
used, including those under "Internet Private Enterprise Numbers"
(1.3.6.1.4.1.x) assigned by IANA
<http://www.iana.org/cgi-bin/enterprise.pl>.
To avoid interoperability problems between early implementations of a
"work in progress" and implementations of the published specification
(e.g., the RFC), experimental OIDs SHOULD be used in "works in
progress" and early implementations. OIDs under the Internet
Experimental OID arc (1.3.6.1.3.x) may be used for this purpose.
Experimental OIDs SHALL NOT be used in published specifications (e.g.
RFCs).
Practices for IANA assignment of Internet Enterprise and Experimental
OIDs are detailed in STD 16 [RFC1155].
3.2 Protocol Mechanisms
LDAP provides a number of Root DSE attributes for discovery of
protocol mechanisms identified by OIDs, including:
- supportedControl [Models],
- supportedExtension [Models], and
- supportedFeatures [Features],
A registry of OIDs used for discover of protocol mechanisms is
provided to allow implementors and others to locate the technical
specification for these protocol mechanisms. Future specifications
of additional Root DSE attributes holding values identifying protocol
mechanisms MAY extend this registry for their values.
OIDs associated with discoverable protocol mechanisms SHOULD be
registered. These are be considered on a First Come First Served
with Specification Required basis.
OIDs associated with Standard Track mechanisms MUST be registered and
require Standards Action.
3.3. Object Identifier Descriptors
Zeilenga IANA Considerations for LDAP [Page 4]
INTERNET-DRAFT draft-ietf-ldapbis-bcp64-00.txt 20 June 2003
LDAP allows short descriptive names (or descriptors) to be used
instead of a numeric Object Identifier to identify protocol
extensions [Protocol], schema elements [Models], LDAP URL [LDAPURL]
extensions, and other objects.
Descriptors SHOULD be registered unless in private-use name space
(e.g., they begin with "x-"). Descriptors defined in RFCs MUST be
registered.
While the protocol allows the same descriptor to refer to different
object identifiers in certain cases and the registry supports
multiple registrations of the same descriptor (each indicating a
different kind of schema element and different object identifier),
multiple registrations of the same descriptor are to be avoided. All
such registration requests require Expert Review.
Descriptors are restricted to strings of UTF-8 encoded UCS characters
restricted by the following ABNF:
name = keystring
Descriptors are case-insensitive.
Multiple names may be assigned to a given OID. For purposes of
registration, an OID is to be represented in numeric OID form
conforming to the ABNF:
numericoid = number *( DOT number ) ; e.g. 1.1.0.23.40
While the protocol places no maximum length restriction upon
descriptors, they should be short. Descriptors longer than 48
characters may be viewed as too long to register.
A values ending with a hyphen ("-") reserve all descriptors which
start with the value. For example, the registration of the option
"descrFamily-" reserves all options which start with "descrFamily-"
for some related purpose.
Descriptors beginning with "x-" are for Private Use and cannot be
registered.
Descriptors beginning with "e-" are reserved for experiments and will
be registered on a First Come First Served basis.
All other descriptors require Expert Review to be registered.
The registrant need not "own" the OID being named.
Zeilenga IANA Considerations for LDAP [Page 5]
INTERNET-DRAFT draft-ietf-ldapbis-bcp64-00.txt 20 June 2003
The OID name space is managed by The ISO/IEC Joint Technical
Committee 1 - Subcommittee 6.
3.4. AttributeDescription Options
An AttributeDescription [Models] can contain zero or more options
specifying additional semantics. An option SHALL be restricted to a
string UTF-8 encoded UCS characters limited by the following ABNF:
option = keystring
Options are case-insensitive.
While the protocol places no maximum length restriction upon option
strings, they should be short. Options longer than 24 characters may
be viewed as too long to register.
Values ending with a hyphen ("-") reserve all option names which
start with the name. For example, the registration of the option
"optionFamily-" reserves all options which start with "optionFamily-"
for some related purpose.
Options beginning with "x-" are for Private Use and cannot be
registered.
Options beginning with "e-" are reserved for experiments and will be
registered on a First Come First Served basis.
All other options require Standards Action or Expert Review with
Specification Required to be registered.
3.5. LDAP Message Types
Each protocol message is encapsulated in an LDAPMessage envelope
[Protocol]. The protocolOp CHOICE indicates the type of message
encapsulated. Each message type consists of a keyword and a
non-negative choice number is combined with the class (APPLICATION)
and data type (CONSTRUCTED or PRIMITIVE) to construct the BER tag in
the message's encoding. The choice numbers for existing protocol
messages are implicit in the protocol's ASN.1 defined in [Protocol].
New values will be registered upon Standards Action.
Note: LDAP provides extensible messages which reduces, but does not
eliminate, the need to add new message types.
Zeilenga IANA Considerations for LDAP [Page 6]
INTERNET-DRAFT draft-ietf-ldapbis-bcp64-00.txt 20 June 2003
3.6. LDAP Result Codes
LDAP result messages carry an resultCode enumerated value to indicate
the outcome of the operation [Protocol]. Each result code consists
of a keyword and a non-negative integer.
New resultCodes integers in the range 0-1023 require Standards Action
to be registered. New resultCode integers in the range 1024-4095
require Expert Review with Specification Required. New resultCode
integers in the range 4096-16383 will be registered on a First Come
First Served basis. Keywords associated with integers in the range
0-4095 SHALL NOT start with "e-" or "x-". Keywords associated with
integers in the range 4096-16383 SHALL start with "e-". Values
greater than or equal to 16384 and keywords starting with "x-" are
for Private Use and cannot be registered.
3.7. LDAP Authentication Method
The LDAP Bind operation supports multiple authentication methods
[Protocol]. Each authentication choice consists of a keyword and a
non-negative integer.
The registrant SHALL classify the authentication method usage using
one of the following terms:
COMMON - method is appropriate for common use on the
Internet,
LIMITED USE - method is appropriate for limited use,
OBSOLETE - method has been deprecated or otherwise found to be
inappropriate for any use.
Methods without publicly available specifications SHALL NOT be
classified as COMMON. New registrations of class OBSOLETE cannot be
registered.
New authentication method integers in the range 0-1023 require
Standards Action to be registered. New authentication method
integers in the range 1024-4095 require Expert Review with
Specification Required. New authentication method integers in the
range 4096-16383 will be registered on a First Come First Served
basis. Keywords associated with integers in the range 0-4095 SHALL
NOT start with "e-" or "x-". Keywords associated with integers in
the range 4096-16383 SHALL start with "e-". Values greater than or
equal to 16384 and keywords starting with "x-" are for Private Use
and cannot be registered.
Note: LDAP supports SASL [RFC2222] as an Authentication CHOICE. SASL
Zeilenga IANA Considerations for LDAP [Page 7]
INTERNET-DRAFT draft-ietf-ldapbis-bcp64-00.txt 20 June 2003
is an extensible LDAP authentication method.
3.8. Directory Systems Names
The IANA-maintained "Directory Systems Names" registry [IANADSN] of
valid keywords for well known attributes used in the LDAPv2 string
representation of a distinguished name [RFC1779], now Historic
[RFC3494].
Directory systems names are not known to be used in any other
context. LDAPv3 uses Object Identifier Descriptors [Section 3.2]
(which have a different syntax than directory system names).
New Directory System Names will no longer be accepted. For
historical purposes, the current list of registered names should
remain publicly available.
4. Registration Procedure
The procedure given here MUST be used by anyone who wishes to use a
new value of a type described in Section 3 of this document.
The first step is for the requester to fill out the appropriate form.
Templates are provided in Appendix A.
If the policy is Standards Action, the completed form SHOULD be
provided to the IESG with the request for Standards Action. Upon
approval of the Standards Action, the IESG SHALL forward the request
(possibly revised) to IANA. The IESG SHALL be viewed as the owner of
all values requiring Standards Action.
If the policy is Expert Review, the requester SHALL post the
completed form to the <directory@apps.ietf.org> mailing list for
public review. The review period is two (2) weeks. If a revised
form is later submitted, the review period is restarted. Anyone may
subscribe to this list by sending a request to
<directory-request@apps.ietf.org>. During the review, objections may
be raised by anyone (including the Expert) on the list. After
completion of the review, the Expert, based upon public comments,
SHALL either approve the request and forward it to the IESG OR deny
the request. In either case, the Expert SHALL promptly notify the
requester of the action. Actions of the Expert may be appealed
[RFC2026]. The Expert is appointed by Applications Area Director(s).
The requester is viewed as the owner of values registered under
Expert Review.
Zeilenga IANA Considerations for LDAP [Page 8]
INTERNET-DRAFT draft-ietf-ldapbis-bcp64-00.txt 20 June 2003
If the policy is First Come First Served, the requester SHALL submit
the completed form directly to the IANA: <iana@iana.org>. The
requester is viewed as the owner of values registered under First
Come First Served.
Neither the Expert nor IANA will take position on the claims of
copyright or trademarks issues regarding completed forms.
Prior to submission of the Internet Draft (I-D) to the RFC Editor but
after IESG review and tentative approval, the document editor SHOULD
revise the I-D to use registered values.
5. Registration Maintenance
This section discusses maintenance of registrations.
5.1. Lists of Registered Values
IANA makes lists of registered values readily available to the
Internet community on their web site: <http://www.iana.org/>.
5.2. Change Control
The registration owner MAY update the registration subject to the
same constraints and review as with new registrations. In cases
where the owner is not unable or unwilling to make necessary updates,
the IESG MAY assert ownership in order to update the registration.
5.3. Comments
For cases where others (anyone other than the owner) have significant
objections to the claims in a registration and the owner does not
agree to change the registration, comments MAY be attached to a
registration upon Expert Review. For registrations owned by the
IESG, the objections SHOULD be addressed by initiating a request for
Expert Review.
The form to these requests is ad hoc, but MUST include the specific
objections to be reviewed and SHOULD contain (directly or by
reference) materials supporting the objections.
6. Security Considerations
Zeilenga IANA Considerations for LDAP [Page 9]
INTERNET-DRAFT draft-ietf-ldapbis-bcp64-00.txt 20 June 2003
The security considerations detailed in BCP 26 [RFC2434] are
generally applicable to this document. Additional security
considerations specific to each name space are discussed in Section 3
where appropriate.
Security considerations for LDAP are discussed in documents
comprising the technical specification [Roadmap].
7. Acknowledgment
This document is a product of the IETF LDAP Revision (LDAPBIS)
Working Group (WG). This document is a revision of RFC 3383, also a
product of the LDAPBIS WG.
This document includes text borrowed from "Guidelines for Writing an
IANA Considerations Section in RFCs" [RFC2434] by Thomas Narten and
Harald Alvestrand.
8. Author's Address
Kurt D. Zeilenga
OpenLDAP Foundation
Email: Kurt@OpenLDAP.org
9. Normative References
[RFC1155] Rose, M. and K. McCloghrie, "Structure and
Identification of Management Information for TCP/IP-
based Internets", STD 16 (also RFC 1155), May 1990.
[RFC2026] Bradner, S., "The Internet Standards Process -- Revision
3", BCP 9 (also RFC 2026), October 1996.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14 (also RFC 2119), March 1997.
[RFC2234] Crocker, D. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", RFC 2234, November 1997.
[Roadmap] Zeilenga, K. (editor), "LDAP: Technical Specification
Road Map", draft-ietf-ldapbis-roadmap-xx.txt, a work in
progress.
[Protocol] Sermersheim, J. (editor), "LDAP: The Protocol",
Zeilenga IANA Considerations for LDAP [Page 10]
INTERNET-DRAFT draft-ietf-ldapbis-bcp64-00.txt 20 June 2003
draft-ietf-ldapbis-protocol-xx.txt, a work in progress.
[Models] Zeilenga, K. (editor), "LDAP: Directory Information
Models", draft-ietf-ldapbis-models-xx.txt, a work in
progress.
[LDAPURL] Smith, M. (editor), "LDAP: Uniform Resource Locator",
draft-ietf-ldapbis-url-xx.txt, a work in progress.
[UTF-8] Yergeau, F., "UTF-8, a transformation
format of ISO 10646", draft-yergeau-rfc2279bis, a work
in progress.
[RFC2434] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26 (also RFC
2434), October 1998.
[RFC3377] Hodges, J. and R. Morgan, "Lightweight Directory Access
Protocol (v3): Technical Specification", RFC 3377,
September 2002.
[ISO10646] International Organization for Standardization,
"Universal Multiple-Octet Coded Character Set (UCS) -
Architecture and Basic Multilingual Plane", ISO/IEC
10646-1 : 1993.
10. Informative References
[RFC1779] Kille, S., "A String Representation of Distinguished
Names", RFC 1779, March 1995.
[RFC3494] Zeilenga, K., "Lightweight Directory Access Protocol
version 2 (LDAPv2) to Historic Status", RFC 3494, March
2003.
[RFC2222] Myers, J., "Simple Authentication and Security Layer
(SASL)", RFC 2222, October 1997.
Appendix A. Registration Templates
This appendix provides registration templates for registering new
LDAP values.
A.1. LDAP Object Identifier Registration Template
Subject: Request for LDAP OID Registration
Zeilenga IANA Considerations for LDAP [Page 11]
INTERNET-DRAFT draft-ietf-ldapbis-bcp64-00.txt 20 June 2003
Person & email address to contact for further information:
Specification: (I-D)
Author/Change Controller:
Comments:
(Any comments that the requester deems relevant to the request)
A.2. LDAP Protocol Mechanism Registration Template
Subject: Request for LDAP Protocol Mechanism Registration
Object Identifier:
Description:
Person & email address to contact for further information:
Usage: (One of Control or Extension or Feature)
Specification: (I-D)
Author/Change Controller:
Comments:
(Any comments that the requester deems relevant to the request)
A.3. LDAP Descriptor Registration Template
Subject: Request for LDAP Descriptor Registration
Descriptor (short name):
Object Identifier:
Person & email address to contact for further information:
Usage: (One of attribute type, URL extension,
object class, or other)
Specification: (RFC, I-D, URI)
Author/Change Controller:
Zeilenga IANA Considerations for LDAP [Page 12]
INTERNET-DRAFT draft-ietf-ldapbis-bcp64-00.txt 20 June 2003
Comments:
(Any comments that the requester deems relevant to the request)
A.4. LDAP Attribute Description Option Registration Template
Subject: Request for LDAP Attribute Description Option Registration
Option Name:
Family of Options: (YES or NO)
Person & email address to contact for further information:
Specification: (RFC, I-D, URI)
Author/Change Controller:
Comments:
(Any comments that the requester deems relevant to the request)
A.5. LDAP Message Type Registration Template
Subject: Request for LDAP Message Type Registration
LDAP Message Name:
Person & email address to contact for further information:
Specification: (Approved I-D)
Comments:
(Any comments that the requester deems relevant to the request)
A.6. LDAP Result Code Registration Template
Subject: Request for LDAP Result Code Registration
Result Code Name:
Person & email address to contact for further information:
Specification: (RFC, I-D, URI)
Zeilenga IANA Considerations for LDAP [Page 13]
INTERNET-DRAFT draft-ietf-ldapbis-bcp64-00.txt 20 June 2003
Author/Change Controller:
Comments:
(Any comments that the requester deems relevant to the request)
A.7. LDAP Authentication Method Registration Template
Subject: Request for LDAP Authentication Method Registration
Authentication Method Name:
Person & email address to contact for further information:
Specification: (RFC, I-D, URI)
Intended Usage: (One of COMMON, LIMITED-USE, OBSOLETE)
Author/Change Controller:
Comments:
(Any comments that the requester deems relevant to the request)
Appendix B. Changes since RFC 3383
This informative appendix provides a summary of changes made since RFC
3383.
- Object Identifier Descriptors practices were updated to require
all descriptors defined in RFCs to be registered and
recommending all other descriptors (excepting those in
private-use name space) be registered. Additionally, all
requests for multiple registrations of the same descriptor are
now subject to Expert Review.
- Protocol Mechanisms practices were updated to include values of
the 'supportedFeatures' attribute type.
- References to RFCs comprising the LDAP technical specifications
have been updated to latest revisions.
- The "Assigned Values" appendix providing initial registry values
was removed.
- Numerous editorial changes were made.
Zeilenga IANA Considerations for LDAP [Page 14]
INTERNET-DRAFT draft-ietf-ldapbis-bcp64-00.txt 20 June 2003
Full Copyright
Copyright (C) The Internet Society (2003). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implmentation may be prepared, copied, published and
distributed, in whole or in part, without restriction of any kind,
provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. 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 needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be followed,
or as required to translate it into languages other than English.
Zeilenga IANA Considerations for LDAP [Page 15]