Dynamic Host Configuration Working Group Steve Drach INTERNET-DRAFT Sun Microsystems, Inc. August 1998 Expires February 1999 DHCP Option for User Authentication Protocol Status of this Memo This document is an Internet-Draft. 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." To view the entire list of current Internet-Drafts, please check the "1id-abstracts.txt" listing contained in the Internet-Drafts Shadow Directories on ftp.is.co.za (Africa), ftp.nordu.net (Northern Europe), ftp.nis.garr.it (Southern Europe), munnari.oz.au (Pacific Rim), ftp.ietf.org (US East Coast), or ftp.isi.edu (US West Coast). Abstract This document defines a DHCP [1] option that contains a pointer to a User Authentication Protocol server that provides user authentication services for clients that conform to The Open Group Network Computer Technical Standard. Introduction The Open Group Network Computer Technical Standard, a product of The Open Group's Network Computer Working Group (NCWG), defines a network computer user authentication facility named the User Authentication Protocol (UAP). UAP provides two levels of authentication, basic and secure. Basic authentication uses the Basic Authentication mechanism defined in the HTTP 1.1 [2] specification. Secure authentication is simply basic authentication encapsulated in an SSLv3 [3] session. In both cases, a UAP client needs to obtain the IP address and port of the UAP service. Additional path information may be required, Drach [Page 1] INTERNET-DRAFT User Authentication Protocol August 1998 depending on the implementation of the service. A URL [4] is an excellent mechanism for encapsulation of this information since many UAP servers will be implemented as components within legacy HTTP/SSL servers. Most UAP clients have no local state and are configured when booted through DHCP. No existing DHCP option [5] has a data field that contains a URL. Option 72 contains a list of IP addresses for WWW servers, but it is not adequate since a port and/or path can not be specified. Hence there is a need for an option that contains a URL. User Authentication Protocol Option This option specifies a URL pointing to a user authentication service that will process authentication requests encapsulated in the User Authentication Protocol (UAP). UAP servers can accept either HTTP 1.1 or SSLv3 connections. If the URL does not contain a port component, the normal default port is assumed (i.e., port 80 for http and port 443 for https). 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Code | Length | URL +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Code TBD Length The length of the data field (i.e., URL) in bytes. URL URL pointing to the UAP service. References [1] Droms, R., "Dynamic Host Configuration Protocol", RFC-2131, March 1997. [2] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., and T. Berners-Lee, "Hypertext Transfer Protocol -- HTTP/1.1", RFC- 2068, January 1997. [3] Freier, A., Karlton, P., and P. Kocher, "The SSL Protocol, Ver- sion 3.0", Internet Draft, November 1996. Drach [Page 2] INTERNET-DRAFT User Authentication Protocol August 1998 [4] Berners-Lee, T., Masinter, L., and M. McCahill, "Uniform Resource Locators (URL)", RFC-1738, December 1994. [5] Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor Extensions", RFC-2132, March 1997. Security Considerations DHCP currently provides no authentication or security mechanisms. Potential exposures to attack are discussed in section 7 of the DHCP protocol specification. Author's Address Steve Drach Sun Microsystems, Inc. 901 San Antonio Road Palo Alto, CA 94303 Phone: (650) 960-1300 EMail: drach@sun.com Drach [Page 3]