INTERNET-DRAFT Kurt D. Zeilenga Intended Category: Informational OpenLDAP Foundation Expires: 19 June 2000 19 December 1999 LDAP Password Modify Extended Operation 1. Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. This draft document will be submitted to the RFC Editor as a Informational document. Distribution of this memo is unlimited. Technical discussion of this document will take place on the IETF LDAP Extension Working Group mailing list . Please send editorial comments directly to the author . 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 1999, The Internet Society. All Rights Reserved. Please see the Copyright section near the end of this document for more information. 2. Abstract The integration of LDAP [RFC2251] and external authentication services has introducted non-DN authentication identities and allowed for non- directory storage of passwords. As such, mechanisms which update the directory, such as Modify operation, cannot be used to change a user's password. This document describes an LDAP extended operation to allow allow modification of user passwords which is not dependent upon the password storage mechanism used. Zeilenga [Page 1] INTERNET-DRAFT LDAP Passwd Ex Op 19 December 1999 The key words ``MUST'', ``MUST NOT'', ``REQUIRED'', ``SHALL'', ``SHALL NOT'', ``SHOULD'', ``SHOULD NOT'', ``RECOMMENDED'', and ``MAY'' in this document are to be interpreted as described in RFC 2119 [RFC2119]. 3. Background and Intent of Use Lightweight Directory Access Protocol (LDAP) [RFC2251] is designed to support an number of authentication mechanisms including simple user name/password pairs. Traditionally LDAP users where identified by the Distinguished Name [RFC2253] of a directory entry and this entry contained a userPassword [RFC2256] attribute containing one or more passwords. The protocol does not mandate that passwords associated with a user be stored in the directory. Implementation are free to use alternative storage and some implementations do support non-directory storage of passwords. The integration of application neutral SASL [RFC2222] services which support simple username/password mechanisms (such as DIGEST-MD5) has introduced non-LDAP DN authentication identity forms and made storage of passwords the responsibility of the SASL service provider. LDAP update operations are designed to act upon attributes of an entry within the directory. LDAP update operations cannot be used to modify a user's password when the user is not represented by a DN, does not have a entry, and that password used by the server is not stored as an attribute of an entry. Alternative mechanism are needed. This document describes an LDAP Extended Operation intended to be allow directory clients to update user passwords. The user may or may not have be associated with a directory entry and may or may not be represented as an LDAP DN. The user's password may or may not be stored in the directory. The operation SHOULD NOT be used used when adequate security protection is not provided. 4. Password Modify Request and Response The Password Modify operation is an LDAPv3 Extended Operation [RFC2251, Section 4.12] and is identified by the OBJECT IDENTIFIER passwdModifyOID. This section details the syntax of the protocol request and response. Zeilenga [Page 2] INTERNET-DRAFT LDAP Passwd Ex Op 19 December 1999 passwdModifyOID OBJECT IDENTIFER ::= 1.3.6.1.4.1.4203.666.6.1 [Editor's Note: this OID is temporary. A permanent OID will be assigned to this object before this document is progressed as an RFC.] PasswdModifyRequestValue ::= SEQUENCE { userIdentity [0] OCTET STRING OPTIONAL oldPasswd [1] OCTET STRING OPTIONAL newPasswd [2] OCTET STRING OPTIONAL } PasswordModifyResponseValue ::= SEQUENCE { genPasswd [0] OCTET STRING OPTIONAL } 4.1. Password Modify Request A Password Modify request is an ExtendedRequest with the requestName field containing passwdModifyOID OID and optionally provides a requestValue field. If the requestValue field is provided, it MUST contain a PasswdModifyRequestValue with one or more fields present. The userIdentity field, if present, MUST contain an octet string representation of the user associated with the request. This string may or may not be an LDAPDN [RFC2253]. If no userIdentity field is present, the request acts up upon the password of the user currently associated with the LDAP session. The oldPasswd field, if present, MUST contain the user's current password. The newPasswd field, if present, MUST contain the desired password for this user. 4.2. Password Modify Response A Password Modify response is an ExtendedResponse where the responseName field is absent and the response field is optional. The response field, if present, MUST containing a PasswdModifyResponseValue with genPasswd field present. The genPasswd field, if present, MUST contain a generated password for the user. If an resultCode other than success (0) is indicated in the response, the response field MUST be absent. Zeilenga [Page 3] INTERNET-DRAFT LDAP Passwd Ex Op 19 December 1999 5. Operation Requirements Upon successfully changing the user's password, the server SHALL return success. The server SHALL NOT return success if the user password has not be changed. The server SHALL NOT change the user password if it does not supports the combination of fields provided in the request. The server SHALL NOT change the user password if the provided oldPasswd value is incorrect. The server MAY generate a password on behalf of the client if and only if newPassword is not present. The server MUST provide the generated password upon success as the value of the genPasswd field. The server MAY return a referral. 6. Other requirements A server which supports this operation SHOULD provide a supportedExtension attribute in the ROOT DSE which contains as one of its values the passwdModifyOID OID. A server MAY advertise the extension only when the client is authorized and/or has established the necessary security protections to use this operation. Client SHOULD verify the server has advertised the extension before attempting the operation. The operation SHOULD NOT be used without adequate security protection, such as offerred by TLS and IPSEC. This operation SHOULD NOT be used by "anonymous" clients. 7. Security Considerations The operation described by this document does not provide any security protection to ensure integrity and/or confidientiality. 8. Copyright Copyright 1999, The Internet Society. 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 Zeilenga [Page 4] INTERNET-DRAFT LDAP Passwd Ex Op 19 December 1999 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 AUTHORS, 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. 9. Bibliography [RFC2219] S. Bradner, "Key words for use in RFCs to Indicate Requirement Levels", RFC 2119, March 1997. [RFC2222] J. Myers, "Simple Authentication and Security Layer (SASL)", RFC 2222, October 1997. [RFC2251] M. Wahl, T. Howes, S. Kille, "Lightweight Directory Access Protocol (v3)", RFC 2251, December 1997. [RFC2252] M. Wahl, A. Coulbeck, T. Howes, S. Kille, "Lightweight Directory Access Protocol (v3): Attribute Syntax Definitions", RFC 2252, December 1997. [RFC2253] M. Wahl, S. Kille, T. Howes, "Lightweight Directory Access Protocol (v3): UTF-8 String Representation of Distinguished Names", RFC 2253, December 1997. [RFC2256] M. Wahl, "A Summary of the X.500(96) User Schema for use with LDAPv3", RFC 2256, December 1997. 10. Acknowledgement Zeilenga [Page 5] INTERNET-DRAFT LDAP Passwd Ex Op 19 December 1999 This document borrows from a number of IETF documents and is based upon input from the IETF LDAPext working group. 11. Author's Address Kurt D. Zeilenga OpenLDAP Foundation Zeilenga [Page 6]