Subject: Submission: draft-weltman-ldapv3-proxy-06.txt

From: Rob Weltman <[email-masked]>
Date: Mon, 06 Nov 2000 12:08:16 -0800

The attached update of the proxied authorization control draft was submitted for publication last night.

Rob

Network Working Group                                        Rob Weltman 
INTERNET-DRAFT                                            November, 2000 
    
                   LDAP Proxied Authorization Control 
                   draft-weltman-ldapv3-proxy-06.txt 

Status of this Memo 
 
   This document is an Internet-Draft and is in full conformance with 
   all provisions of Section 10 of RFC2026. 
    
   Internet-Drafts are working documents of the Internet 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. 

Abstract 
    
   This document defines support for the Proxied Authorization Control. 
   Controls are an LDAP protocol version 3 extension, to allow passing 
   arbitrary control information along with a standard request to a 
   server, and to receive arbitrary information back with a standard 
   result. The Proxied Authorization Control allows a client to request  
   that an operation be processed under a provided authorization 
   identity [AUTH] instead of as the current authorization identity 
   associated with the connection. 

1. Introduction 
    
   Version 3 of the LDAP protocol provides a means of supplying 
   arbitrary additional information along with a request to an LDAP 
   server, and receiving arbitrary additional response information. The 
   Control protocol extension is described in [LDAPV3], section 4.1.12. 
   This document defines support for proxied authorization using the 
   Control mechanism. 
    
   The key words "MUST", "SHOULD", and "MAY" used in this document  are  
   to be interpreted as described in [KEYWORDS]. 

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2. Publishing support for the Proxied Authorization Control 
    
   Support for the Proxied Authorization Control is indicated by the 
   presence of the OID "2.16.840.1.113730.3.4.18" in the 
   supportedControl attribute of a server's root DSE. 

3. Proxied Authorization Control 

   This control may be included in any search, compare, modify, add, 
   delete, modDN or extended operation request message as part of the 
   controls field of the LDAPMessage, as defined in [LDAPV3]. 
    
   The controlType of the proxied authorization control is 
   "2.16.840.1.113730.3.4.18". 
    
   The criticality MUST be included and MUST be TRUE. 
    
   The control value is the BER encoded authorization identity to use 
   for the request. 

4. Permission to execute as proxy 
    
   An LDAP server supporting the Proxied Authorization Control may 
   choose to honor or not honor a particular request. If the control is 
   supported but a particular request is denied, the server MUST return 
   the error code insufficientAccessRights. 
    
   A typical implementation will evaluate if the requester has proxy 
   access rights at the base DN of the request. If the requester has 
   proxy access rights, and if the authorization identity is recognized 
   by the server, the request will be honored. If the request is 
   honored, it will be executed as if submitted by the proxy identity. 
    
   During evaluation of a search request, an entry which would have been 
   returned for the search if submitted by the proxy identity directly 
   may not be returned if the server finds that the requester does not 
   have proxy rights to the entry, even if the entry is within the scope 
   of a search request under a base DN which does imply such rights. 
   This means that fewer results, or no results, may be returned 
   compared to the case where the proxy identity issued the request 
   directly. An example of such a case may be a system with fine-grained 
   access control, where the proxy right requester has proxy rights at 
   the top of a search tree, but not at or below a point or points 
   within the tree. 

5. Security Considerations 

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   The Proxied Authorization Control method is subject to standard LDAP 
   security considerations. The control may be passed over a secure as 
   well as over an insecure channel. 
    
   The control allows for an additional authorization identity to be 
   passed. In some deployments, these identities may contain 
   confidential information which require privacy protection. 
    
   Note that the server is responsible for determining if a proxied 
   authorization request is to be honored. 

6. Copyright 
    
   Copyright (C) The Internet Society (date). 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 implementation 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. 
    
   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. 

7. Bibliography 
    
   [LDAPV3] M. Wahl, T. Howes, S. Kille, "Lightweight Directory Access 
        Protocol (v3)", RFC 2251, December 1997. 
    
   [KEYWORDS] Bradner, Scott, "Key Words for use in RFCs to Indicate 
        Requirement Levels", draft-bradner-key-words-03.txt, January, 
        1997. 
    
   [AUTH] M. Wahl, H. Alvestrand, J. Hodges, R. Morgan, "Authentication 
        Methods for LDAP", RFC 2829, May 2000 

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8. Author's Address 
    
   Rob Weltman 
   +1 650 461 1708 
   [email-masked] 

9. Acknowledgements 
    
   Mark Smith of Netscape Communications Corp., Mark Wahl of Sun 
   Microsystems, Inc, and Kurt Zeilenga of OpenLDAP Foundation have 
   contributed with reviews of this draft. 

10. Changes from draft-weltman-ldapv3-proxy-05.txt 
    
   The control also applies to add and extended operations. 
    
   The control value is an authorization ID, not necessarily a DN. 
    
   Confidentiality concerns are mentioned. 

11. Changes from draft-weltman-ldapv3-proxy-04.txt 
    
   The control does not apply to bind, unbind, or abandon operations. 
    
   The proxy DN is represented as a string in the control, rather than 
   embedded in a sequence. 
    
   Support for the control is published in the supportedControl 
   attribute of the root DSE, not in supportedExtensions. 
    
   The security section mentions confidentiality issues with exposing an 
   additional identity. 

12. Changes from draft-weltman-ldapv3-proxy-03.txt 
    
   None 

13. Changes from draft-weltman-ldapv3-proxy-02.txt 

13.1 Renamed Control 
    
   The Control is now called Proxied Authorization Control, rather than 
   Proxied Authentication Control, to reflect that no authentication 
   occurs as a consequence of processing the Control. 

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13.2 Control envelope 
    
   Rather than containing an LDAPDN as the Control value, the Control 
   contains a Sequence (which contains an LDAPDN). This is to provide 
   for future extensions. 

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