Network Working Group S. Krishnan Internet-Draft Ericsson Intended status: Standards Track November 02, 2007 Expires: May 5, 2008 Authorization Certificates for Routers and Proxies draft-krishnan-cgaext-send-cert-eku-00 Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. 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 May 5, 2008. Copyright Notice Copyright (C) The IETF Trust (2007). Krishnan Expires May 5, 2008 [Page 1] Internet-Draft Router and Proxy Certificates November 2007 Abstract Secure Neighbor Discovery (SEND) Utilizes X.509v3 certificates for performing router authorization. The certificates that are currently recommended can be used for any purpose. This document specifies the extended key usage values for such certificates which explicitly states the purpose for which these certificates are used. Table of Contents 1. Requirements notation . . . . . . . . . . . . . . . . . . . . 3 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 3. Extended Key Usage Values . . . . . . . . . . . . . . . . . . 5 4. Security Considerations . . . . . . . . . . . . . . . . . . . 7 5. Normative References . . . . . . . . . . . . . . . . . . . . . 8 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 9 Intellectual Property and Copyright Statements . . . . . . . . . . 10 Krishnan Expires May 5, 2008 [Page 2] Internet-Draft Router and Proxy Certificates November 2007 1. Requirements notation 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]. Krishnan Expires May 5, 2008 [Page 3] Internet-Draft Router and Proxy Certificates November 2007 2. Introduction Secure Neighbor Discovery [RFC3971] Utilizes X.509v3 certificates for performing router authorization. It uses the X.509 extension for IP addresses to verify whether the router is authorized to advertise the mentioned IP addresses. Since the IP addresses extension does not mention what functions the node can perform for the IP addresses it becomes impossible to know the reason for which the certificate was issued. In order to facilitate issuance of certificates for specific functions, we need to utilize the ExtKeyUsageSyntax field of the X.509 certificate to mention the purpose for which the certificate was issued. This document specifies two extended key usage values, one for routers and one for proxies, for use with SEND. Krishnan Expires May 5, 2008 [Page 4] Internet-Draft Router and Proxy Certificates November 2007 3. Extended Key Usage Values The Internet PKI document [RFC3280] specifies the extended key usage X.509 certificate extension. The extension indicates one or more purposes for which the certified public key may be used. The extended key usage extension can be used in conjunction with key usage extension, which indicates the intended purpose of the certified public key. The extended key usage extension syntax is repeated here for convenience: ExtKeyUsageSyntax ::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId KeyPurposeId ::= OBJECT IDENTIFIER This specification defines two KeyPurposeId values: one for authorizing routers, and one for authorizing proxies. The inclusion of the router authorization value indicates that the certificate has been issued for allowing the router to advertise prefix(es) that are mentioned using the X.509 extensions for IP addresses and AS identifiers [RFC3779] The inclusion of the proxy authorization value indicates that the certificate has been issued for allowing the proxy to perform proxying of neighbor discovery messages for the prefix(es) that are mentioned using the X.509 extensions for IP addresses and AS identifiers [RFC3779] Inclusion of both values indicates that the certified public key is appropriate for use by a node performing either proxying or advertising of prefixes. send-kp OBJECT IDENTIFIER ::= { iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) TBA1 } id-kp-sendRouter OBJECT IDENTIFIER ::= { send-kp 1 } id-kp-sendProxy OBJECT IDENTIFIER ::= { send-kp 2 } The extended key usage extension MAY, at the option of the certificate issuer, be either critical or non-critical. Certificate-using applications MAY require the extended key usage extension to be present in a certificate, and they MAY require a particular KeyPurposeId value to be present (such as id-kp-sendRouter Krishnan Expires May 5, 2008 [Page 5] Internet-Draft Router and Proxy Certificates November 2007 or id-kp-sendProxy) within the extended key usage extension. If multiple KeyPurposeId values are included, the certificate-using application need not recognize all of them, as long as the required KeyPurposeId value is present. Krishnan Expires May 5, 2008 [Page 6] Internet-Draft Router and Proxy Certificates November 2007 4. Security Considerations The certification authority needs to ensure that the correct values for the extended key usage are inserted in each certificate that is issued. Relying parties may accept or reject a particular certificate for an intended use based on the information provided in these extensions. Incorrect representation of the information in the extended key usage field can cause the relying party to reject an otherwise appropriate certificate or accept a certificate that ought to be rejected. Krishnan Expires May 5, 2008 [Page 7] Internet-Draft Router and Proxy Certificates November 2007 5. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC3280] Housley, R., Polk, W., Ford, W., and D. Solo, "Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile", RFC 3280, April 2002. [RFC3779] Lynn, C., Kent, S., and K. Seo, "X.509 Extensions for IP Addresses and AS Identifiers", RFC 3779, June 2004. [RFC3971] Arkko, J., Kempf, J., Zill, B., and P. Nikander, "SEcure Neighbor Discovery (SEND)", RFC 3971, March 2005. Krishnan Expires May 5, 2008 [Page 8] Internet-Draft Router and Proxy Certificates November 2007 Author's Address Suresh Krishnan Ericsson 8400 Decarie Blvd. Town of Mount Royal, QC Canada Phone: +1 514 345 7900 x42871 Email: suresh.krishnan@ericsson.com Krishnan Expires May 5, 2008 [Page 9] Internet-Draft Router and Proxy Certificates November 2007 Full Copyright Statement Copyright (C) The IETF Trust (2007). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. 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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. Acknowledgment Funding for the RFC Editor function is provided by the IETF Administrative Support Activity (IASA). Krishnan Expires May 5, 2008 [Page 10]