Network Working Group Vijayabhaskar A Kalusivalingam Internet-Draft Hewlett-Packard Expires: Jun 2004 Dec 2003 NIS Configuration Options for DHCPv6 draft-ietf-dhc-dhcpv6-opt-nisconfig-05 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. This Internet-Draft will expire on Jun 2004. Copyright Notice Copyright (C) The Internet Society (2003). All Rights Reserved. Abstract This document describes four options for Network Information Service (NIS) related configuration information in DHCPv6: NIS Servers, NIS+ Servers, NIS Client Domain Name, NIS+ Client Domain name. 1. Introduction This document describes four options for passing configuration information related to Network Information Service (NIS) [3] in DHCPv6 (RFC 3315 [1]). 2. Terminology 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 RFC2119 [2]. Vijay Expires Jun, 2004 [Page 1] Internet-Draft NIS Configuration Options for DHCPv6 Dec 2003 Throughout this document, unless otherwise specified, the acronym DHCP refers to DHCP as specified in RFC 3315. This document uses terminology specific to IPv6 and DHCP as defined in section "Terminology" of RFC 3315. 3. Network Information Service (NIS) Servers Option The Network Information Service (NIS) Servers option provides a list of one or more IPv6 addresses of NIS servers available to the client. Clients MUST treat the list of NIS servers as an ordered list. The server MAY list the NIS servers in the order of preference. The format of the Network Information Service Servers option is as shown below: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | OPTION_NIS_SERVERS | option-len | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | NIS server (IPv6 address) | | | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | NIS server (IPv6 address) | | | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ option-code: OPTION_NIS_SERVERS (tbd) option-len: Length of the 'NIS server' fields in octets; It must be a multiple of 16 NIS server: IPv6 address of NIS server 4. Network Information Service V2 (NIS+) Servers Option The Network Information Service V2 (NIS+) Servers option provides a list of one or more IPv6 addresses of NIS+ servers available to the client. Clients MUST treat the list of NIS+ servers as an ordered list. The server MAY list the NIS+ servers in the order of preference. The format of the Network Information Service V2 (NIS+) Servers option is as shown below: Vijay Expires Jun, 2004 [Page 2] Internet-Draft NIS Configuration Options for DHCPv6 Dec 2003 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | OPTION_NISP_SERVERS | option-len | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | NIS+ server (IPv6 address) | | | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | NIS+ server (IPv6 address) | | | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ option-code: OPTION_NISP_SERVERS (tbd) option-len: Length of the 'NIS+ server' fields in octets; It must be a multiple of 16 NIS+ server: IPv6 address of NIS+ server 5. Network Information Service (NIS) Domain Name Option The Network Information Service (NIS) Domain Name option is used by the server to convey client's NIS Domain Name info to the client. The format of the NIS Domain Name option is as shown below: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | OPTION_NIS_DOMAIN_NAME | option-len | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | nis-domain-name | | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ option-code: OPTION_NIS_DOMAIN_NAME (tbd) option-len: Length of the 'nis-domain-name' field in octets nis-domain-name: NIS Domain name for client The 'nis-domain-name' MUST be encoded as specified in section "Representation and Use of domain names" of the DHCPv6 specification [1]. Vijay Expires Jun, 2004 [Page 3] Internet-Draft NIS Configuration Options for DHCPv6 Dec 2003 6. Network Information Service V2 (NIS+) Domain Name Option The Network Information Service V2 (NIS+) Domain Name option is used by the server to convey client's NIS+ Domain Name info to the client. The format of the NIS+ Domain Name option is as shown below: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | OPTION_NISP_DOMAIN_NAME | option-len | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | nisp-domain-name | | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ option-code: OPTION_NISP_DOMAIN_NAME (tbd) option-len: Length of the 'nisp-domain-name' field in octets nisp-domain-name: NIS+ Domain name for client The 'nisp-domain-name' MUST be encoded as specified in section "Representation and Use of domain names" of the DHCPv6 specification [1]. 7. Appearance of these Options The NIS servers, NIS+ servers, NIS domain name and NIS+ domain name options MUST NOT appear in other than the following messages: Solicit, Advertise, Request, Renew, Rebind, Information-Request and Reply. The option number for these options MAY appear in the Option Request Option [1] in the following messages: Solicit, Request, Renew, Rebind, Information-Request and Reconfigure. 8. Security Considerations The NIS servers, NIS+ servers, NIS domain name and NIS+ domain name options may be used by an intruder DHCPv6 server to assign invalid NIS parameters, resulting in clients unable to use NIS service. The NIS servers and NIS+ servers options may be used by an intruder DHCPv6 server to cause the DHCPv6 clients to send their queries to an intruder NIS/NIS+ server. This misdirected searches may be used to spoof NIS/NIS+ names. The NIS domain name and NIS+ domain name options may be used by an intruder DHCPv6 server to cause the DHCPv6 clients to search through invalid domains for incompletely specified domain names. The results of these misdirected searches may be used to spoof NIS/NIS+ names. Vijay Expires Jun, 2004 [Page 4] Internet-Draft NIS Configuration Options for DHCPv6 Dec 2003 To avoid attacks through these options, the DHCPv6 client SHOULD use authenticated DHCP (see section "Authentication of DHCP messages" in the DHCPv6 specification [1]). 9. IANA Considerations IANA is requested to assign an option code to the following options from the option-code space defined in "DHCPv6 Options" section of the DHCPv6 specification [1]. Option Name Value Described in OPTION_NIS_SERVERS tbd Section 3 OPTION_NISP_SERVERS tbd Section 4 OPTION_NIS_DOMAIN_NAME tbd Section 5 OPTION_NISP_DOMAIN_NAME tbd Section 6 10. Normative References [1] Bound, J., Carney, M., Perkins, C., Lemon, T., Volz, B. and R. Droms (ed.), "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)", RFC 3315, July 2003. [2] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. 11. Informative References [3] Sun Microsystems, "System and Network Administration", March 1990. Author's Address Vijayabhaskar A Kalusivalingam Hewlett-Packard STSD-I 29, Cunningham Road Bangalore - 560052 India Phone: +91-80-2053085 E-Mail: vijayak@india.hp.com Vijay Expires Jun, 2004 [Page 5] Internet-Draft NIS Configuration Options for DHCPv6 Dec 2003 Full Copyright Statement Copyright (C) The Internet Society (2003). 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. Acknowledgement Funding for the RFC Editor function is currently provided by the Internet Society. Thanks to the DHC Working Group for their time and input into the specification. In particular, thanks to (in alphabetical order) Bernie Volz, Jim Bound, Margaret Wasserman, Pekka Savola, Ralph Droms and Thomas Narten for their thorough review. Vijay Expires Jun, 2004 [Page 6]