The application/pkix-attr-cert Media Type for Attribute Certificates
The registered media type for sending a single attribute certificate.
Housley, R., "The application/pkix-attr-cert Media Type for Attribute Certificates", RFC 5877, DOI 10.17487/RFC5877, May 2010, <https://www.rfc-editor.org/info/rfc5877>.
@misc{rfc5877,
series = {Request for Comments},
number = 5877,
howpublished = {RFC 5877},
publisher = {RFC Editor},
doi = {10.17487/RFC5877},
url = {https://www.rfc-editor.org/info/rfc5877},
author = {R. Housley},
title = {{The application/pkix-attr-cert Media Type for Attribute Certificates}},
pagetotal = 4,
year = 2010,
month = may,
} RFC text
Contents
Internet Engineering Task Force (IETF) R. Housley Request for Comments: 5877 Vigil Security Category: Informational May 2010 ISSN: 2070-1721 The application/pkix-attr-cert Media Type for Attribute Certificates Abstract This document specifies a MIME media type used to carry a single attribute certificate as defined in RFC 5755. Status of This Memo This document is not an Internet Standards Track specification; it is published for informational purposes. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Not all documents approved by the IESG are a candidate for any level of Internet Standard; see Section 2 of RFC 5741. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc5877. Copyright Notice Copyright (c) 2010 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 (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. 1. Introduction RFC 2585 [RFC2585] defines the MIME media types for public key certificates and certificate revocation lists (CRLs). This document specifies a MIME media type for use with attribute certificates as defined in RFC 5755 [RFC5755]. Attribute certificates are ASN.1 encoded [X.680]. RFC 5755 [RFC5755] tells which portions of the attribute certificate must use the distinguished encoding rules (DER) [X.690] and which portions are permitted to use the basic encoding rules (BER) [X.690]. Since DER is a proper subset of BER, BER decoding all parts of a properly constructed attribute certificate will be successful. 2. IANA Considerations This document registers with IANA the "application/pkix-attr-cert" Internet Media Type for use with an attribute certificate as defined in [RFC5755]. This registration follows the procedures defined in BCP 13 [RFC4288]. Type name: application Subtype name: pkix-attr-cert Required parameters: None Optional parameters: None Encoding considerations: binary Security considerations: An attribute certificate provides authorization information. An attribute certificate is most often used in conjunction with a public key certificate [RFC5280], and the two certificates should use the same encoding of the distinguished name as described in the Security Considerations of this document. Interoperability considerations: The media type will be used with HTTP to fetch attribute certificates. Other uses may emerge in the future. Published specification: RFC 5755 Applications that use this media type: The media type is used with a MIME-compliant transport to transfer an attribute certificate. Attribute certificates convey authorization information, and they are most often used in conjunction with public key certificates as defined in [RFC5280]. Additional information: Magic number(s): None File extension(s): .ac Macintosh File Type Code(s): none Person & email address to contact for further information: Russ Housley housley@vigilsec.com Intended usage: COMMON Restrictions on usage: none Author: Russ Housley <housley@vigilsec.com> Intended usage: COMMON Change controller: The IESG <iesg@ietf.org> 3. Security Considerations Attribute certificate issuers must encode the holder entity name in exactly the same way as the public key certificate distinguished name. If they are encoded differently, implementations may fail to recognize that the attribute certificate and public key certificate belong to the same entity. 4. References 4.1. Normative References [RFC5755] Farrell, S., Housley, R., and S. Turner, "An Internet Attribute Certificate Profile for Authorization", RFC 5755, January 2010. 4.2. Informative References [RFC2585] Housley, R. and P. Hoffman, "Internet X.509 Public Key Infrastructure Operational Protocols: FTP and HTTP", RFC 2585, May 1999. [RFC4288] Freed, N. and J. Klensin, "Media Type Specifications and Registration Procedures", BCP 13, RFC 4288, December 2005. [RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S., Housley, R., and W. Polk, "Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile", RFC 5280, May 2008. [X.680] ITU-T Recommendation X.680 (2002) | ISO/IEC 8824-1:2002, Information technology - Abstract Syntax Notation One (ASN.1): Specification of basic notation. [X.690] ITU-T Recommendation X.690 (2002) | ISO/IEC 8825-1:2002, Information technology - ASN.1 encoding rules: Specification of Basic Encoding Rules (BER), Canonical Encoding Rules (CER) and Distinguished Encoding Rules (DER). Author's Address Russell Housley Vigil Security, LLC 918 Spring Knoll Drive Herndon, VA 20170 USA EMail: housley@vigilsec.com
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On this page
§1Why a New Media Type
RFC 2585 defines MIME media types for public key certificates and certificate revocation lists. RFC 5877 adds one for attribute certificates as defined in RFC 5755.
Attribute certificates are ASN.1 encoded. RFC 5755 says which parts must use DER and which may use BER. Since DER is a proper subset of BER, BER decoding all parts of a properly constructed attribute certificate will succeed.
Some certificates already had labels for their envelopes. The permission-card certificate was missing one, so this note adds it.
§2The Registration
The type name is application and the subtype name is pkix-attr-cert. There are no required or optional parameters, and the encoding is binary. The file extension is .ac, and there is no magic number. The intended usage is COMMON, and the change controller is the IESG.
The media type will be used with HTTP to fetch attribute certificates, and other uses may emerge. Attribute certificates convey authorization information and are most often used with public key certificates.
The label says: this is a program-type file, it is a binary attribute certificate, and files like it end in .ac.
§3Security Considerations
Attribute certificate issuers must encode the holder entity name in exactly the same way as the public key certificate distinguished name. If they are encoded differently, implementations may fail to recognize that both certificates belong to the same entity.
If a name is written one way on one card and another way on the second, the two cards might not be matched to the same person.