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Versions: 00                                                            
  INTERNET-DRAFT                                             Eric A. Hall
  Document: draft-ietf-crisp-lw-user-00.txt                     July 2002
  Expires: January, 2003
  Category: Experimental
                    Defining and Locating Contact Persons
                  using the Internet Resource Query Service
     Status of this Memo
     This document is an Internet-Draft and is in full conformance with
     all provisions of Section 10 of RFC 2026.
     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-
     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
     The list of current Internet-Drafts can be accessed at
     The list of Internet-Draft Shadow Directories can be accessed at
  1.      Abstract
     This document defines LDAP schema and searching rules for contact
     persons, in support of the Internet Resource Query Service
     described in [ldap-whois].
  Internet Draft     draft-ietf-crisp-lw-user-00.txt         July 2002
  2.      Definitions and Terminology
     This document unites, enhances and clarifies several pre-existing
     technologies. Readers are expected to be familiar with the
     following specifications:
            RFC 2247 - Using Domains in LDAP/X.500 DNs
            RFC 2251 - Lightweight Directory Access Protocol (v3)
            RFC 2252 - Lightweight Directory Access Protocol (v3):
            Attribute Syntax Definitions.
            RFC 2254 - The String Representation of LDAP Search Filters
            RFC 2798 - Definition of the inetOrgPerson LDAP Object
            [ir-dir-req] - <draft-newton-ir-dir-requirements-00.txt> -
            Internet Registry Directory Requirements
            [ldap-whois] - <draft-ietf-crisp-lw-core-00.txt> - The
            Internet Resource Query Service and the Internet Resource
     The following abbreviations are used throughout this document:
            DIT (Directory Information Tree) - A DIT is a contained
            branch of the LDAP namespace, having a root of a particular
            distinguished name. "dc=example,dc=com" is used throughout
            this document as one DIT, with many example entries being
            stored in this DIT.
            DN (Distinguished Name) - A distinguished name provides a
            unique identifier for an entry, through the use of a multi-
            level naming syntax. Entries are named according to their
            location relevant to the root of their containing DIT. For
            example, "cn=inetResources,dc=example,dc=com" is a DN which
            uniquely identifies the "inetResources" entry within the
            "dc=example,dc=com" DIT.
            RDN (Relative DN) - An RDN provides a locally-scoped unique
            identifier for an entry. A complete, globally-unique DN is
            formed by concatenating the RDNs of an entry together. For
            example, "cn=admins,cn=inetResources,dc=example,dc=com"
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  Internet Draft     draft-ietf-crisp-lw-user-00.txt         July 2002
            consists of two RDNs ("cn=admins" and "cn=inetResources")
            within the "dc=example,dc=com" DIT. RDNs are typically only
            referenced within their local scope.
            OID (Object Identifier) - An OID is a globally-unique,
            concatenated set of integers which provide a kind of
            "serial number" to attributes, object classes, syntaxes and
            other schema elements.
     The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL
     in this document are to be interpreted as described in RFC 2119.
  3.      The inetOrgPerson Object Class
     This document provides several contact-related attributes which
     use LDAP URLs to reference inetOrgPerson entries. Whenever one of
     these contact attributes are returned, a separate query for the
     inetOrgPerson entry associated with the contact attribute will be
     required if the details of that contact are needed. In order to
     facilitate programmatic access to this data, LDAP URLs provided in
     contact attributes MUST refer to entries which use the
     inetOrgPerson object class, MUST refer to an entry in a DIT which
     uses the domainComponent object class syntax ("dc="), and MUST
     specify the LDAP or LDAPS protocol-types for the URL.
     The model put forth in this document allows each contact attribute
     to refer to a variable number of contacts. In this model, a query
     for a contact attribute MAY return a variable number of LDAP URLs,
     and each of these contacts can then be queried individually. This
     allows for multiple explicit contacts per role, while also
     providing predictable naming and query structures.
     The target entries MAY exist anywhere in the LDAP hierarchy (as
     long as they follow the domainComponent naming syntax). It is
     expected that pre-existing inetOrgPerson entries will be used for
     this purpose. If this is not desirable or feasible, then an entry
     MUST be created which meets the minimum requirements defined in
     this document. Regardless of where the entry is located, the
     target inetOrgPerson entries MUST conform with the schema
     specification defined in RFC 2798.
     The target inetOrgPerson entries MAY have any number of attributes
     defined, with any number of access restrictions, as required by
     local security policies, government regulations or personal
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  Internet Draft     draft-ietf-crisp-lw-user-00.txt         July 2002
     privacy concerns. However, the mail attribute MUST be defined,
     MUST be valid, and MUST have anonymous read permissions.
     Furthermore, all of the attributes MUST be secured against
     anonymous add, delete and modify permissions.
  4.      inetOrgPerson equalityMatch
     The inetOrgPerson object class entries can be searched using
     relatively simple equalityMatch filters.
     In order to ensure that all of the relevant entries (including any
     referrals) are found, the search filters for these resources MUST
     specify two distinct elements: the object class of the resource
     being queried, and the naming element of the resource specified as
     a distinguished name attribute.
     For example, using the notation format described in RFC 2254, the
     search filter expression for the inetOrgPerson entry associated
     with "cn=admins,ou=admins,dc=example,dc=com" would be structured
     as "(&(objectclass=inetOrgPerson)(cn:dn:=admins))", using
     "ou=admins,dc=example,dc=com" as the search base. This would find
     all entries with the object class of inetOrgPerson (including all
     of the referral entries for inetOrgPerson entries) where the
     distinguished name contained the "cn" attribute of "admins".
     The input source and search base for these matches will vary
     according to the query being processed, but whenever an
     equalityMatch is called for during query processing, the above
     methods MUST be used in order to ensure that all of the related
     entries are located.
     Response entries MAY be fully-developed entries, or MAY be
     referrals generated from entries which have the referral object
     class defined. Any attribute values which are received MUST be
     displayed by the client. If a subordinate reference referral is
     received, the client MUST restart the query, using the provided
     data as the new search base. If any continuation reference
     referrals are received, the client SHOULD start new queries for
     each reference, and append the output of those queries to the
     original query's output.
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  Internet Draft     draft-ietf-crisp-lw-user-00.txt         July 2002
  5.      Security Considerations
     This document describes an application of the LDAPv3 protocol, and
     as such it inherits the security considerations associated with
     LDAPv3, as described in section 7 of RFC 2251.
     By nature, LDAP is a read-write protocol, while the legacy WHOIS
     service has always been a read-only service. As such, there are
     significant risks associated with allowing unintended updates by
     unauthorized third-parties. Moreover, allowing the LDAP-WHOIS
     service to update the underlying delegation databases could result
     in network resources being stolen from their lawful operators. For
     example, if the LDAP front-end had update access to a domain
     delegation database, a malicious third-party could theoretically
     take ownership of that domain by exploiting an authentication
     weakness, thereby causing ownership of the domain to be changed to
     another party. For this reason, it is imperative that the LDAP-
     WHOIS service not be allowed to make critical modifications to
     delegated resources without ensuring that all possible precautions
     have been taken.
     The query processing models described in this document make use of
     DNS lookups in order to locate the LDAP servers associated with a
     particular resource. DNS is susceptible to certain attacks and
     forgeries which may be used to redirect clients to LDAP servers
     which are not authoritative for the resource in question.
     Some operators may choose to purposefully provide misleading or
     erroneous information in an effort to avoid responsibility for bad
     behavior. In addition, there are likely to be sporadic operator
     errors which will result in confusing or erroneous answers.
     This document provides multiple query models which will cause the
     same query to be answered by different servers (one would be
     processed by a delegation entity, while another would be processed
     by an operational entity). As a result, each of the servers may
     provide different information, depending upon the query type that
     was originally selected.
     For all of the reasons listed above, it is essential that
     applications and end-users not make critical decisions based on
     the information provided by the LDAP-WHOIS service without having
     reason to believe the veracity of the information. Users should
     limit unknown or untrusted information to routine purposes.
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  Internet Draft     draft-ietf-crisp-lw-user-00.txt         July 2002
     Finally, there are physical security issues associated with any
     service which provides physical addressing and delivery
     information. Although organizations are generally encouraged to
     provide as much information as they feel comfortable with, no
     information is required.
  6.      IANA Considerations
     This document defines an application of the LDAPv3 protocol rather
     than a new Internet application protocol. As such, there are no
     protocol-related IANA considerations.
     However, this document does define several LDAP schema elements,
     including object classes, attributes, syntaxes and extensibleMatch
     filters, and these elements should be assigned OID values from the
     IANA branch, rather than being assigned from a particular
     enterprise branch.
     Finally, this document also describes several instances where
     public DNS and LDAP servers are queried. It is expected that IANA
     will establish and maintain these LDAP servers (and the necessary
     DNS SRV domain names and resource records) required for this
     service to operate. This includes providing SRV resource records
     in the generic TLDs and the root domain, and also includes
     administering the referenced LDAP servers.
  7.      Author's Addresses
     Eric A. Hall
  8.      References
            RFC 2247 - Using Domains in LDAP/X.500 DNs
            RFC 2251 - Lightweight Directory Access Protocol (v3)
            RFC 2252 - Lightweight Directory Access Protocol (v3):
            Attribute Syntax Definitions.
            RFC 2254 - The String Representation of LDAP Search Filters
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  Internet Draft     draft-ietf-crisp-lw-user-00.txt         July 2002
            [ir-dir-req] - <draft-newton-ir-dir-requirements-00.txt> -
            Internet Registry Directory Requirements
            [ldap-whois] - <draft-ietf-crisp-lw-core-00.txt> - The
            Internet Resource Query Service and the Internet Resource
  9.      Acknowledgments
     Portions of this work were funded by Network Solutions, Inc.
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