NETWORK WG Sean Turner, IECA Internet Draft Russ Housley, Vigil Security Intended Status: Standards Track December 7, 2009 Expires: June 7, 2010 Additional CMS Revocation Information Choices draft-turner-additional-cms-ri-choices-03.txt Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and 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 June 7, 2010. Copyright Notice Copyright (c) 2009 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents in effect on the date of publication of this document (http://trustee.ietf.org/license-info). Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Turner & Housley Expires June 7, 2010 [Page 1] Internet-Draft Additional CMS Revocation Information Choices Dec 2009 Abstract The Cryptographic Message Syntax (CMS) allows revocation information to be conveyed as part of the SignedData, EnvelopedData, AuthenticatedData, and AuthEnvelopedData content types. The preferred format for revocation information is the Certificate Revocation List (CRL), but an extension mechanism supports other revocation information choices. This document defines two additional revocation information formats for Online Certificate Status Protocol (OCSP) responses and Server-Based Certificate Validation Protocol (SCVP). 1. Introduction The RevocationInfoChoices type defined in [CMS] provides a set of revocation status information alternatives, which allows revocation information to be conveyed as part of the SignedData, EnvelopedData, AuthenticatedData, and AuthEnvelopedData content types. The intent is to provide information sufficient to determine whether the certificates and attribute certificates carried elsewhere in the CMS protecting content are revoked. However, there MAY be more revocation status information than necessary or there MAY be less revocation status information than necessary. X.509 Certificate revocation lists (CRLs) [PROFILE] are the primary source of revocation status information, but any other revocation information formats can be supported. This document specifies two other formats: Online Certificate Status Protocol (OCSP) responses [OCSP] and Server-Based Certificate Validation Protocol (SCVP) responses [SCVP]. 1.1. Requirements 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 [WORDS]. 2. Revocation Information For convenience, the ASN.1 definition of the RevocationInfoChoices type from [CMS] is repeated here: RevocationInfoChoices ::= SET OF RevocationInfoChoice RevocationInfoChoice ::= CHOICE { crl CertificateList, other [1] IMPLICIT OtherRevocationInfoFormat } Turner & Housley Expires June 7, 2010 [Page 2] Internet-Draft Additional CMS Revocation Information Choices Dec 2009 OtherRevocationInfoFormat ::= SEQUENCE { otherRevInfoFormat OBJECT IDENTIFIER, otherRevInfo ANY DEFINED BY otherRevInfoFormat } The other CHOICE MUST be used to convey OCSP responses, SCVP requests, and SCVP responses. The revocation information choices are defined under the following object identifier arc: id-ri OBJECT IDENTIFIER ::= { iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) ri(16) } 3. OCSP Response To carry an OCSP response, the otherRevInfoFormat is set to id-ri-ocsp-response, which has the following ASN.1 definition: id-ri-ocsp-response OBJECT IDENTIFIER ::= { id-ri 2 } In this case, otherRevInfo MUST carry the OCSP response using the OCSPResponse type defined in [OCSP]. The responseStatus field MUST be successful and the responseBytes field MUST be present. 4. SCVP Request and Response Unlike OSCP, SCVP permits unprotected and protected responses, where protected responses can be digitally signed or include message authentication codes. While this provides more flexibility, it complicates when an SCVP response can be validated by entities other than the entity that generated the SCVP request. If a lower layer provides authentication and integrity for the client-server interaction and the response is not protected, then a third party cannot validate the response because there is no way to know that the response was returned over a protected connection. If a message authentication code is used, then the third party will be unable to validate the message authentication code because it does not posses the necessary private key. For these reasons, SCVP responses sent to a third party MUST be signed by the SCVP server so that the third party can validate them. SCVP response validation requires matching it to the SCVP request. This means that the SCVP request MUST always be included with the response. SCVP permits the client can retain the response, and SCVP permits the request to be returned in the response (in the requestReq field). The request need not be protected for matching to be performed; nonces and certIds can be checked. Turner & Housley Expires June 7, 2010 [Page 3] Internet-Draft Additional CMS Revocation Information Choices Dec 2009 To carry the SCVP request and response, the otherRevInfoFormat is set to id-ri-scvp, which has the following ASN.1 definition: id-ri-scvp OBJECT IDENTIFIER ::= { id-ri 4 } In this case, the otherRevInfo MUST carry both the SCVP request and response with the following structure: SCVPReqRes ::= SEQUENCE { request [0] EXPLICIT ContentInfo OPTIONAL, response ContentInfo } The SCVPReqRes has the following fields: o request contains the SCVP request. It contains the unprotected request, authenticated request, or the signed request. The request MUST be present if the response does not include the requestRef fullRequest field. o response contains the SCVP response. It MUST contain the signed response. Additionally, the responseStatus MUST be okay. Unprotected and authenticated responses MUST NOT be included. 5. Security Considerations The security considerations of [CMS], [CMS-ASN], [OCSP], [SCVP], and [PROFILE-ASN] apply. To locally store unprotected or authenticated SCVP responses, an entity can encapsulate the unprotected or authenticated SCVP response in a SignedData. It is a matter of local policy whether these encapsulated SCVP responses are considered valid by another entity. 6. IANA Considerations This document makes use of object identifiers. These object identifiers are defined in an arc delegated by IANA to the PKIX Working Group. No further action by IANA is necessary for this document or any anticipated updates. 7. References 7.1. Normative References [CMS] Housley, R., "Cryptographic Message Syntax", RFC 5652, September 2009. Turner & Housley Expires June 7, 2010 [Page 4] Internet-Draft Additional CMS Revocation Information Choices Dec 2009 [OCSP] Meyers, M., Ankney, R., Malpani, A., Galperin, S., and C. Adams, "X.509 Internet Public Key Infrastructure Online Certificate Status Protocol - OCSP", RFC 2560, June 1999. [SCVP] Freeman, T., Housley, R., Malpani, A., Cooper, D., and W. Polk, "Server-Based Certificate Validation Protocol (SCVP)", RFC 5055, December 2007. [WORDS] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [X.680] ITU-T Recommendation X.680 (2002) | ISO/IEC 8824- 1:2002. Information Technology - Abstract Syntax Notation One. [X.681] ITU-T Recommendation X.681 (2002) | ISO/IEC 8824- 2:2002. Information Technology - Abstract Syntax Notation One: Information Object Specification. [X.682] ITU-T Recommendation X.682 (2002) | ISO/IEC 8824- 3:2002. Information Technology - Abstract Syntax Notation One: Constraint Specification. [X.683] ITU-T Recommendation X.683 (2002) | ISO/IEC 8824- 4:2002. Information Technology - Abstract Syntax Notation One: Parameterization of ASN.1 Specifications, 2002. 7.2. Informative References [CMS-ASN] Hoffman, P., and J. Schaad, "New ASN.1 Modules for CMS", draft-ietf-smime-new-asn1, work-in-progress. [PROFILE-ASN] Hoffman, P., and J. Schaad, "New ASN.1 Modules for PKIX", draft-ietf-pkix-new-asn1, work-in-progress. [PROFILE] Cooper, D. et. al., "Internet X.509 Public Key Infrastructure Certificate and Certification Revocation List (CRL) Profile", RFC 5280, May 2008. Appendix A. ASN.1 Modules Appendix A.1 provides the normative ASN.1 definitions for the structures described in this specification using ASN.1 as defined in [X.680] for compilers that support the 1988 ASN.1. Turner & Housley Expires June 7, 2010 [Page 5] Internet-Draft Additional CMS Revocation Information Choices Dec 2009 Appendix A.2 provides informative ASN.1 definitions for the structures described in this specification using ASN.1 as defined in [X.680], [X.681], [X.682], and [X.683] for compilers that support the 2002 ASN.1. This appendix contains the same information as Appendix A.1 in a more recent (and precise) ASN.1 notation, however Appendix A.1 takes precedence in case of conflict. A.1. 1988 ASN.1 Module CMS-Other-RIs-2009-88 { iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0) id-mod-cms-otherRIs-2009-88(63) } DEFINITIONS IMPLICIT TAGS ::= BEGIN -- EXPORTS ALL IMPORTS -- FROM CMS [CMS] ContentInfo FROM CryptographicMessageSyntax2004 { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) modules(0) cms-2004(24) } ; id-ri OBJECT IDENTIFIER ::= { iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) ri(16) } -- RevocationInfoChoice for OCSP response -- OID included in otherRevInfoFormat -- signed OCSP response included in otherRevInfo id-ri-ocsp-response OBJECT IDENTIFIER ::= { id-ri 2 } -- RevocationInfoChoice for SCVP response -- OID included in otherRevInfoFormat -- SCVPReqRes included in otherRevInfo id-ri-scvp OBJECT IDENTIFIER ::= { id-ri 4 } Turner & Housley Expires June 7, 2010 [Page 6] Internet-Draft Additional CMS Revocation Information Choices Dec 2009 SCVPReqRes ::= SEQUENCE { request [0] EXPLICIT ContentInfo OPTIONAL, response ContentInfo } END A.2. 2002 ASN.1 Module CMS-Other-RIs-2009-02 { iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0) id-mod-cms-otherRIs-2009-93(64) } DEFINITIONS IMPLICIT TAGS ::= BEGIN -- EXPORT ALL IMPORTS -- FROM [PROFILE-ASN] OCSPResponse FROM OCSP-2009 { iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0) id-mod-ocsp-02(48) } -- FROM [CMS-ASN] ContentInfo, OTHER-REVOK-INFO FROM CryptographicMessageSyntax-2009 { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) modules(0) id-mod-cms-2004-02(41) } ; -- Defines OCSP and SCVP choices for RevocationInfoChoice SupportedOtherRevokInfo OTHER-REVOK-INFO ::= { ri-ocsp-response | ri-scvp, ... } ri-ocsp OTHER-REVOK-INFO ::= { OCSPResponse IDENTIFIED BY id-ri-ocsp-response } Turner & Housley Expires June 7, 2010 [Page 7] Internet-Draft Additional CMS Revocation Information Choices Dec 2009 id-ri OBJECT IDENTIFIER ::= { iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) ri(16) } id-ri-ocsp-response OBJECT IDENTIFIER ::= { id-ri 2 } ri-scvp OTHER-REVOK-INFO ::= { SCVPReqRes IDENTIFIED BY id-ri-scvp } id-ri-scvp OBJECT IDENTIFIER ::= { id-ri 4 } SCVPReqRes ::= SEQUENCE { request [0] EXPLICIT ContentInfo OPTIONAL, response ContentInfo } END Authors' Addresses Sean Turner IECA, Inc. 3057 Nutley Street, Suite 106 Fairfax, VA 22031 USA EMail: turners@ieca.com Russ Housley Vigil Security, LLC 918 Spring Knoll Drive Herndon, VA 20170 USA EMail: housley@vigilsec.com Turner & Housley Expires June 7, 2010 [Page 8]