Lightweight Directory Access Protocol (LDAP) "Who am I?" Operation
RFC 4532

Document Type RFC - Proposed Standard (June 2006; Errata)
Was draft-zeilenga-ldap-authzid (individual in app area)
Author Kurt Zeilenga 
Last updated 2020-01-21
Stream Internet Engineering Task Force (IETF)
Formats plain text html pdf htmlized (tools) htmlized with errata bibtex
Stream WG state (None)
Document shepherd No shepherd assigned
IESG IESG state RFC 4532 (Proposed Standard)
Action Holders
Consensus Boilerplate Unknown
Telechat date
Responsible AD Ted Hardie
Send notices to (None)
Network Working Group                                        K. Zeilenga
Request for Comments: 4532                           OpenLDAP Foundation
Category: Standards Track                                      June 2006

              Lightweight Directory Access Protocol (LDAP)
                         "Who am I?" Operation

Status of This Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2006).


   This specification provides a mechanism for Lightweight Directory
   Access Protocol (LDAP) clients to obtain the authorization identity
   the server has associated with the user or application entity.  This
   mechanism is specified as an LDAP extended operation called the LDAP
   "Who am I?" operation.

1.  Background and Intent of Use

   This specification describes a Lightweight Directory Access Protocol
   (LDAP) [RFC4510] operation that clients can use to obtain the primary
   authorization identity, in its primary form, that the server has
   associated with the user or application entity.  The operation is
   called the "Who am I?" operation.

   This specification is intended to replace the existing Authorization
   Identity Controls [RFC3829] mechanism, which uses Bind request and
   response controls to request and return the authorization identity.
   Bind controls are not protected by security layers established by the
   Bind operation that includes them.  While it is possible to establish
   security layers using StartTLS [RFC4511][RFC4513] prior to the Bind
   operation, it is often desirable to use security layers established
   by the Bind operation.  An extended operation sent after a Bind
   operation is protected by the security layers established by the Bind

Zeilenga                    Standards Track                     [Page 1]
RFC 4532               LDAP "Who am I?" Operation              June 2006

   There are other cases where it is desirable to request the
   authorization identity that the server associated with the client
   separately from the Bind operation.  For example, the "Who am I?"
   operation can be augmented with a Proxied Authorization Control
   [RFC4370] to determine the authorization identity that the server
   associates with the identity asserted in the Proxied Authorization
   Control.  The "Who am I?" operation can also be used prior to the
   Bind operation.

   Servers often associate multiple authorization identities with the
   client, and each authorization identity may be represented by
   multiple authzId [RFC4513] strings.  This operation requests and
   returns the authzId that the server considers primary.  In the
   specification, the term "the authorization identity" and "the
   authzId" are generally to be read as "the primary authorization
   identity" and the "the primary authzId", respectively.

1.1.  Conventions Used in This Document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   document are to be interpreted as described in BCP 14 [RFC2119].

2.  The "Who am I?" Operation

   The "Who am I?" operation is defined as an LDAP Extended Operation
   [RFC4511] identified by the whoamiOID Object Identifier (OID).  This
   section details the syntax of the operation's whoami request and
   response messages.

      whoamiOID ::= ""

2.1.  The whoami Request

   The whoami request is an ExtendedRequest with a requestName field
   containing the whoamiOID OID and an absent requestValue field.  For
   example, a whoami request could be encoded as the sequence of octets
   (in hex):

      30 1e 02 01 02 77 19 80  17 31 2e 33 2e 36 2e 31
      2e 34 2e 31 2e 34 32 30  33 2e 31 2e 31 31 2e 33

Zeilenga                    Standards Track                     [Page 2]
RFC 4532               LDAP "Who am I?" Operation              June 2006

2.2.  The whoami Response

   The whoami response is an ExtendedResponse where the responseName
   field is absent and the response field, if present, is empty or an
   authzId [RFC4513].  For example, a whoami response returning the
   authzId "u:xxyyz@EXAMPLE.NET" (in response to the example request)
   would be encoded as the sequence of octets (in hex):

      30 21 02 01 02 78 1c 0a  01 00 04 00 04 00 8b 13
      75 3a 78 78 79 79 7a 40  45 58 41 4d 50 4c 45 2e
      4e 45 54

3.  Operational Semantics

   The "Who am I?" operation provides a mechanism, a whoami Request, for
   the client to request that the server return the authorization
   identity it currently associates with the client.  It also provides a
Show full document text