Edit File: draft-legg-ldap-acm-admin-xx.txt
INTERNET-DRAFT S. Legg draft-legg-ldap-acm-admin-03.txt Adacel Technologies Intended Category: Standards Track June 16, 2004 Lightweight Directory Access Protocol (LDAP): Access Control Administration Copyright (C) The Internet Society (2004). All Rights Reserved. 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 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. Distribution of this document is unlimited. Comments should be sent to the author. This Internet-Draft expires on 16 December 2004. Abstract This document adapts the X.500 directory administrative model, as it pertains to access control administration, for use by the Lightweight Directory Access Protocol. The administrative model partitions the Directory Information Tree for various aspects of directory data administration, e.g., subschema, access control and collective attributes. This document provides the particular definitions that support access control administration, but does not define a particular access control scheme. Legg Expires 16 December 2004 [Page 1] INTERNET-DRAFT Access Control Administration June 16, 2004 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Conventions. . . . . . . . . . . . . . . . . . . . . . . . . . 2 3. Access Control Administrative Areas. . . . . . . . . . . . . . 3 4. Access Control Scheme Indication . . . . . . . . . . . . . . . 3 5. Access Control Information . . . . . . . . . . . . . . . . . . 4 6. Access Control Subentries. . . . . . . . . . . . . . . . . . . 4 7. Applicable Access Control Information. . . . . . . . . . . . . 5 8. Security Considerations. . . . . . . . . . . . . . . . . . . . 5 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 6 10. IANA Considerations. . . . . . . . . . . . . . . . . . . . . . 6 11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 6 11.1. Normative References. . . . . . . . . . . . . . . . . . 6 11.2. Informative References. . . . . . . . . . . . . . . . . 7 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 7 Full Copyright Statement . . . . . . . . . . . . . . . . . . . . . 7 1. Introduction This document adapts the X.500 directory administrative model [X501], as it pertains to access control administration, for use by the Lightweight Directory Access Protocol (LDAP) [RFC3377]. The administrative model [ADMIN] partitions the Directory Information Tree (DIT) for various aspects of directory data administration, e.g., subschema, access control and collective attributes. The parts of the administrative model that apply to every aspect of directory data administration are described in [ADMIN]. This document describes the administrative framework for access control. An access control scheme describes the means by which access to directory information, and potentially to access rights themselves, may be controlled. This document describes the framework for employing access control schemes but does not define a particular access control scheme. Two access control schemes known as Basic Access Control and Simplified Access Control are defined by [BAC]. Other access control schemes may be defined by other documents. This document is derived from, and duplicates substantial portions of, Sections 4 and 8 of X.501 [X501]. 2. Conventions 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, RFC 2119 [RFC2119]. Legg Expires 16 December 2004 [Page 2] INTERNET-DRAFT Access Control Administration June 16, 2004 Schema definitions are provided using LDAP description formats [RFC2252]. Note that the LDAP descriptions have been rendered with additional white-space and line breaks for the sake of readability. 3. Access Control Administrative Areas The specific administrative area [ADMIN] for access control is termed an Access Control Specific Area (ACSA). The root of the ACSA is termed an Access Control Specific Point (ACSP) and is represented in the DIT by an administrative entry [ADMIN] which includes accessControlSpecificArea as a value of its administrativeRole operational attribute [SUBENTRY]. An ACSA MAY be partitioned into subtrees termed inner administrative areas [ADMIN]. Each such inner area is termed an Access Control Inner Area (ACIA). The root of the ACIA is termed an Access Control Inner Point (ACIP) and is represented in the DIT by an administrative entry which includes accessControlInnerArea as a value of its administrativeRole operational attribute. An administrative entry can never be both an ACSP and an ACIP. The corresponding values can therefore never be present simultaneously in the administrativeRole attribute. Each entry necessarily falls within one and only one ACSA. Each such entry may also fall within one or more ACIAs nested inside the ACSA containing the entry. An ACSP or ACIP has zero, one or more subentries that contain Access Control Information (ACI). 4. Access Control Scheme Indication The access control scheme (e.g., Basic Access Control [BAC]) in force in an ACSA is indicated by the accessControlScheme operational attribute contained in the administrative entry for the relevant ACSP. The LDAP description [RFC2252] for the accessControlScheme operational attribute is: ( 2.5.24.1 NAME 'accessControlScheme' EQUALITY objectIdentifierMatch SYNTAX 1.3.6.1.4.1.1466.115.121.1.38 SINGLE-VALUE USAGE directoryOperation ) An access control scheme conforming to the access control framework described in this document MUST define a distinct OBJECT IDENTIFIER Legg Expires 16 December 2004 [Page 3] INTERNET-DRAFT Access Control Administration June 16, 2004 value to identify it through the accessControlScheme attribute. Object Identifier Descriptors for access control scheme identifiers may be registered with IANA [BCP64]. Only administrative entries for ACSPs are permitted to contain an accessControlScheme attribute. If the accessControlScheme attribute is absent from a given ACSP, the access control scheme in force in the corresponding ACSA, and its effect on operations, results and errors, is implementation defined. Any entry or subentry in an ACSA is permitted to contain ACI if and only if such ACI is permitted by, and consistent with, the access control scheme identified by the value of the accessControlScheme attribute of the ACSP. 5. Access Control Information There are three categories of Access Control Information (ACI): entry, subentry and prescriptive. Entry ACI applies to only the entry or subentry in which it appears, and the contents thereof. Subject to the access control scheme, any entry or subentry MAY hold entry ACI. Subentry ACI applies to only the subentries of the administrative entry in which it appears. Subject to the access control scheme, any administrative entry, for any aspect of administration, MAY hold subentry ACI. Prescriptive ACI applies to all the entries within a subtree or subtree refinement of an administrative area (either an ACSA or an ACIA), as defined by the subtreeSpecification attribute of the subentry in which it appears. Prescriptive ACI is only permitted in subentries of an ACSP or ACIP. Prescriptive ACI in the subentries of a particular administrative point never applies to the same or any other subentry of that administrative point, but does apply to the subentries of subordinate administrative points, where those subentries are within the subtree or subtree refinement. 6. Access Control Subentries Each subentry which contains prescriptive ACI MUST have accessControlSubentry as a value of its objectClass attribute. Such a subentry is called an access control subentry. The LDAP description [RFC2252] for the accessControlSubentry auxiliary object class is: Legg Expires 16 December 2004 [Page 4] INTERNET-DRAFT Access Control Administration June 16, 2004 ( 2.5.17.1 NAME 'accessControlSubentry' AUXILIARY ) A subentry of this object class MUST contain at least one prescriptive ACI attribute of a type consistent with the value of the accessControlScheme attribute of the corresponding ACSP. The subtree or subtree refinement for an access control subentry is termed a Directory Access Control Domain (DACD). A DACD can contain zero entries, and can encompass entries that have not yet been added to the DIT, but does not extend beyond the scope of the ACSA or ACIA with which it is associated. Since a subtreeSpecification may define a subtree refinement, DACDs within a given ACSA may arbitrarily overlap. 7. Applicable Access Control Information Although particular items of ACI may specify attributes or values as the protected items, ACI is logically associated with entries. The ACI that is considered in access control decisions regarding an entry includes: (1) Entry ACI from that particular entry. (2) Prescriptive ACI from access control subentries whose DACDs contain the entry. Each of these access control subentries is necessarily either a subordinate of the ACSP for the ACSA containing the entry, or a subordinate of the ACIP for an ACIA that contains the entry. The ACI that is considered in access control decisions regarding a subentry includes: (1) Entry ACI from that particular subentry. (2) Prescriptive ACI from access control subentries whose DACDs contain the subentry, excluding those belonging to the same administrative point as the subentry for which the decision is being made. (3) Subentry ACI from the administrative point associated with the subentry. 8. Security Considerations This document defines a framework for employing an access control scheme, i.e., the means by which access to directory information and Legg Expires 16 December 2004 [Page 5] INTERNET-DRAFT Access Control Administration June 16, 2004 potentially to access rights themselves may be controlled, but does not itself define any particular access control scheme. The degree of protection provided, and any security risks, are determined by the provisions of the access control schemes (defined elsewhere) making use of this framework. Security considerations that apply to directory administration in general [ADMIN] also apply to access control administration. 9. Acknowledgements This document is derived from, and duplicates substantial portions of, Sections 4 and 8 of X.501 [X501]. 10. IANA Considerations The Internet Assigned Numbers Authority (IANA) is requested to update the LDAP descriptors registry [BCP64] as indicated by the following templates: Subject: Request for LDAP Descriptor Registration Descriptor (short name): accessControlScheme Object Identifier: 2.5.24.1 Person & email address to contact for further information: Steven Legg <steven.legg@adacel.com.au> Usage: attribute type Specification: RFC XXXX Author/Change Controller: IESG Subject: Request for LDAP Descriptor Registration Descriptor (short name): accessControlSubentry Object Identifier: 2.5.17.1 Person & email address to contact for further information: Steven Legg <steven.legg@adacel.com.au> Usage: object class Specification: RFC XXXX Author/Change Controller: IESG 11. References 11.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2252] Wahl, M., Coulbeck, A., Howes, T. and S. Kille, "Lightweight Directory Access Protocol (v3): Attribute Syntax Definitions", RFC 2252, December 1997. Legg Expires 16 December 2004 [Page 6] INTERNET-DRAFT Access Control Administration June 16, 2004 [RFC3377] Hodges, J. and R. Morgan, "Lightweight Directory Access Protocol (v3): Technical Specification", RFC 3377, September 2002. [BCP64] Zeilenga, K., "Internet Assigned Numbers Authority (IANA Considerations for the Lightweight Directory Access Protocol (LDAP)", BCP 64, RFC 3383, September 2002. [SUBENTRY] Zeilenga, K. and S. Legg, "Subentries in the Lightweight Directory Access Protocol (LDAP)", RFC 3672, December 2003. [ADMIN] Legg, S., "Lightweight Directory Access Protocol (LDAP): Directory Administrative Model", draft-legg-ldap-admin-xx.txt, a work in progress, June 2004. 11.2. Informative References [COLLECT] Zeilenga, K., "Collective Attributes in the Lightweight Directory Access Protocol (LDAP)", RFC 3671, December 2003. [BAC] Legg, S., "Lightweight Directory Access Protocol (LDAP): Basic and Simplified Access Control", draft-legg-ldap-acm-bac-xx.txt, a work in progress, June 2004. [X501] ITU-T Recommendation X.501 (02/01) | ISO/IEC 9594-2:2001, Information technology - Open Systems Interconnection - The Directory: Models Author's Address Steven Legg Adacel Technologies Ltd. 250 Bay Street Brighton, Victoria 3186 AUSTRALIA Phone: +61 3 8530 7710 Fax: +61 3 8530 7888 EMail: steven.legg@adacel.com.au Full Copyright Statement Copyright (C) The Internet Society (2004). This document is subject to the rights, licenses and restrictions contained in BCP 78, and Legg Expires 16 December 2004 [Page 7] INTERNET-DRAFT Access Control Administration June 16, 2004 except as set forth therein, the authors retain all their rights. This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM 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. Intellectual Property The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org. Changes in Draft 01 Section 4 has been extracted to become a separate Internet draft, draft-legg-ldap-admin-00.txt. The subsections of Section 5 have become the new Sections 3 to 7. Editorial changes have been made to accommodate this split. No technical changes have been introduced. Changes in Draft 02 RFC 3377 replaces RFC 2251 as the reference for LDAP. An IANA Considerations section has been added. Changes in Draft 03 Legg Expires 16 December 2004 [Page 8] INTERNET-DRAFT Access Control Administration June 16, 2004 The document has been reformatted in line with current practice. Legg Expires 16 December 2004 [Page 9]