Network Working Group Rob Weltman INTERNET-DRAFT Mark Smith Intended Category: Standards Track Netscape Communications Corp. Mark Wahl Sun Microsystems, Inc. October, 2000 LDAP Authentication Response Control draft-weltman-ldapv3-auth-response-02.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 Authentication Request Control and the Authentication Response 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 Authentication Request Control may be submitted by a client in a bind request if authenticating with version 3 of the LDAP protocol. In the LDAP server's bind response, it may then include an Authentication Response Control. The response control contains the identity assumed by the client. This is useful when there is a mapping step or other indirection during the bind, so that the client can be told what LDAP identity was granted. Client authentication with certificates is the primary situation where this applies. Also, some SASL authentication mechanisms may not involve the client explicitly providing a DN. 1. Introduction Expires October 2000 [Page 1] AUTHENTICATION RESPONSE CONTROL April, 2000 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 a way for a server to return the identity assumed by a client on binding using the Control mechanism. The key words "MUST", "SHOULD", and "MAY" used in this document are to be interpreted as described in [RFCKeyWords]. 2. Publishing support for the Authentication Request Control and the Authentication Response Control Support for the Authentication Request Control and the Authentication Response Control is indicated by the presence of the OIDs 2.16.840.1.113730.3.4.16 and 2.16.840.1.113730.3.4.15, respectively, in the supportedExtension attribute of a server's root DSE. 3. Authentication Request Control This control MAY be included in any bind request which specifies protocol version 3, as part of the controls field of the LDAPMessage as defined in [LDAPv3]. The controlType is "2.16.840.1.113730.3.4.16", the criticality field is FALSE or absent, and the controlValue is absent. 4. Authentication Response Control This control may be included in any final bind response where the bind request included an Authentication Request Control, as part of the controls field of the LDAPMessage as defined in [LDAPv3]. The controlType is "2.16.840.1.113730.3.4.15". If the bind request succeeded and resulted in an identity (not anonymous), the controlValue contains the distinguished name of the authentication identity. If the bind request resulted in anonymous authentication, the controlValue field is a string of zero length. If the bind request failed, the control is not included in the bind response. During client authentication with certificates [AUTH], a client may possess more than one certificate and not be able to determine which one was ultimately selected for authentication to the server. The subject DN field in the selected certificate may not correspond exactly to a DN in the directory, but rather have gone through a mapping process controlled by the server. On completing the certificate-based authentication, the client may issue a SASL [SASL] Expires October 2000 [Page 2 AUTHENTICATION RESPONSE CONTROL April, 2000 bind request, specifying the EXTERNAL mechanism and including an Authentication Request Control. The bind response MAY include an authentication response control indicating the DN in the server's DIT which the certificate was mapped to. 5. Security Considerations The Authentication Response Control is subject to standard LDAP security considerations. The control may be passed over a secure as well as over an insecure channel. No additional confidential information is passed in the control. 6. Copyright Copyright (C) The Internet Society (2000). 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. [RFCKeyWords] Bradner, Scott, "Key Words for use in RFCs to Indicate Requirement Levels", draft-bradner-key-words-03.txt, January, 1997. Expires October 2000 [Page 3 AUTHENTICATION RESPONSE CONTROL April, 2000 [AUTH] M. Wahl, H. Alvestrand, J. Hodges, RL "Bob" Morgan, "Authentication Methods for LDAP", RFC 2829, May, 2000. [SASL] J. Myers, "Simple Authentication and Security Layer (SASL", RFC 2222, October, 1997. [ASN.1] X.680 : ITU-T Recommendation X.680 (1997) | ISO/IEC 8824- 1:1998, Information Technology - Abstract Syntax Notation One (ASN.1): Specification of Basic Notation 8. Author's Addresses Rob Weltman +1 650 461 1708 robw@worldspot.com Mark Smith Netscape Communications Corp. Mailstop USCA17-201 4170 Network Circle Santa Clara, CA 95054 USA +1 650 937-3477 mcs@netscape.com Mark Wahl Sun Microsystems, Inc. 911 Capital of Texas Hwy, Suite 4140 Austin, TX 78759 USA +1 512 231 7224 Mark.Wahl@sun.com 9. Changes from draft-weltman-ldapv3-auth-response-01.txt 9.1 Authentication Request Control An Authentication Response Control is now only returned if the client requested one by submitting an Authentication Request Control. 9.2 Contents of Authentication Response Control Rather than returning both the authentication DN and the authentication mechanism, the control only returns the authentication DN. Expires October 2000 [Page 4 AUTHENTICATION RESPONSE CONTROL April, 2000 10. Changes from draft-weltman-ldapv3-auth-response-00.txt 10.1 Capitalization of ASN.1 macros AuthResponseControl and AuthResponseValue are capitalized. 10.2 Clarifications Added sentence on behavior for anonymous binds. Expires October 2000 [Page 5