Internet Engineering Task Force (IETF) A. Bryan Request for Comments: 5843 April 2010 Category: Informational ISSN: 2070-1721 Additional Hash Algorithms for HTTP Instance Digests Abstract The IANA registry named "Hypertext Transfer Protocol (HTTP) Digest Algorithm Values" defines values for digest algorithms used by Instance Digests in HTTP. Instance Digests in HTTP provide a digest, also known as a checksum or hash, of an entire representation of the current state of a resource. This document adds new values to the registry and updates previous values. 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/rfc5843. 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. Bryan Informational [Page 1] RFC 5843 More Algorithms for HTTP Instance Digests April 2010 Table of Contents 1. Introduction ....................................................2 1.1. Example ....................................................2 2. IANA Considerations .............................................2 2.1. Previous Registrations Updated .............................2 2.2. New Registrations ..........................................3 3. Security Considerations .........................................3 4. Changes Compared to RFC 3230 ....................................3 5. Normative References ............................................4 Appendix A. Acknowledgements and Contributors ......................5 1. Introduction The IANA registry named "Hypertext Transfer Protocol (HTTP) Digest Algorithm Values" defines values for digest algorithms used by Instance Digests in HTTP. Note: This is unrelated to HTTP Digest Authentication. Instance Digests in HTTP provide a digest, also known as a checksum or hash, of an entire representation of the current state of a resource. The registry was created by [RFC3230] in 2002. This document adds new values to the registry and updates previous values that had redundant or outdated references. 1.1. Example Example of Instance Digest for SHA-256: Digest: SHA-256=MWVkMWQxYTRiMzk5MDQ0MzI3NGU5NDEyZTk5OWY1ZGFmNzgyZTJlO DYzYjRjYzFhOTlmNTQwYzI2M2QwM2U2MQ== 2. IANA Considerations This document makes use of the IANA registry named "Hypertext Transfer Protocol (HTTP) Digest Algorithm Values" specified in [RFC3230]. 2.1. Previous Registrations Updated Accordingly, IANA has updated the following registrations: Digest Algorithm: MD5 Description: The MD5 algorithm, as specified in [RFC1321]. The output of this algorithm is encoded using the base64 encoding [RFC4648]. Bryan Informational [Page 2] RFC 5843 More Algorithms for HTTP Instance Digests April 2010 Reference: [RFC1321], [RFC4648], this document. Digest Algorithm: SHA Description: The SHA-1 algorithm [FIPS-180-3]. The output of this algorithm is encoded using the base64 encoding [RFC4648]. Reference: [FIPS-180-3], [RFC4648], this document. 2.2. New Registrations Accordingly, IANA has made the following registrations: Digest Algorithm: SHA-256 Description: The SHA-256 algorithm [FIPS-180-3]. The output of this algorithm is encoded using the base64 encoding [RFC4648]. Reference: [FIPS-180-3], [RFC4648], this document. Digest Algorithm: SHA-512 Description: The SHA-512 algorithm [FIPS-180-3]. The output of this algorithm is encoded using the base64 encoding [RFC4648]. Reference: [FIPS-180-3], [RFC4648], this document. 3. Security Considerations Same as [RFC3230]. 4. Changes Compared to RFC 3230 The reference for base64 encoding has been updated for both MD5 and SHA. The reference for SHA has been updated. The SHA-256 and SHA-512 algorithms have been added to the registry. All other previous values to the registry are still valid. Bryan Informational [Page 3] RFC 5843 More Algorithms for HTTP Instance Digests April 2010 5. Normative References [FIPS-180-3] National Institute of Standards and Technology (NIST), "Secure Hash Standard (SHS)", FIPS PUB 180-3, October 2008. [RFC1321] Rivest, R., "The MD5 Message-Digest Algorithm", RFC 1321, April 1992. [RFC3230] Mogul, J. and A. Van Hoff, "Instance Digests in HTTP", RFC 3230, January 2002. [RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data Encodings", RFC 4648, October 2006. Bryan Informational [Page 4] RFC 5843 More Algorithms for HTTP Instance Digests April 2010 Appendix A. Acknowledgements and Contributors Thanks to Mark Nottingham, Eran Hammer-Lahav, Nils Maier, Lisa Dusseault, Alfred Hoenes, Pasi Eronen, Gonzalo Camarillo, Radia Perlman, and Jeffrey Mogul. Author's Address Anthony Bryan Pompano Beach, FL USA EMail: anthonybryan@gmail.com URI: http://www.metalinker.org Bryan Informational [Page 5]