Re: [TLS] [POSSIBLE SPAM] Re: draft-ietf-tls-cached-info-02 / New "Fast-Track" draft
"Kemp, David P." <DPKemp@missi.ncsc.mil> Wed, 24 February 2010 19:48 UTC
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Date: Wed, 24 Feb 2010 14:50:36 -0500
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Thread-Topic: [POSSIBLE SPAM] Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fast-Track" draft
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From: "Kemp, David P." <DPKemp@missi.ncsc.mil>
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Subject: Re: [TLS] [POSSIBLE SPAM] Re: draft-ietf-tls-cached-info-02 / New "Fast-Track" draft
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Marsh Ray wrote: > It will not be so fun to convince reviewers that "yes we're using > SHA-1 but not in a way that really matters." > > If all you need is a 64-bit checksum for data-structure-style > hashing and indexing, use any old old-fashioned checksum algorithm. > > This would be simple for everyone to implement and it clearly > communicates your design intent (that the security of the design > does not depend on any properties of this value's calculation). +1 in principle. But practically speaking, do you have any suggestions for well-known non-cryptographic hash algorithms? A quick IANA search turned up Kerberos checksums http://www.iana.org/assignments/kerberos-parameters/kerberos-parameters.xhtml, including CRC32 (4 octets), des-mac-k (8 octets), and several 16 octet algorithms including MD4 and MD5. A search for other "hash", "mac", or "checksum" registries turned up nothing new. It doesn't feel quite right to add a non-cryptographic checksum to the RFC 5246 registry: enum { none(0), md5(1), sha1(2), sha224(3), sha256(4), sha384(5), sha512(6), (255) } HashAlgorithm; so even if there were such an algorithm, permitting both it and cryptographic hashes would be painful. I don't see an alternative that satisfies both "simple to implement" and "clearly communicates intent". My care-abouts are 1) a common interoperable algorithm and 2) bandwidth. Computation speed is unimportant, so if everyone thinks sha256 will be cryptographically viable for the foreseeable future and SHA-1 will soon be impossible to get "approved", then sha256 truncated to 64 bits could be a reasonable MUST-support algorithm. Dave
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Simon Josefsson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Adam Langley
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Nikos Mavrogiannopoulos
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Adam Langley
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Michael D'Errico
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Nikos Mavrogiannopoulos
- Re: [TLS] Android's cut-through mode & "RequestTi… Brian Smith
- [TLS] Stream multiplexing extension RE: SPDY / Ne… Brian Smith
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- [TLS] TLS Performance (was Re: draft-ietf-tls-cac… Michael D'Errico
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Adam Langley
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Adam Langley
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Adam Langley
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Kemp, David P.
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Martin Rex
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- [TLS] Cached-info substitution Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Kemp, David P.
- Re: [TLS] Cached-info substitution Brian Smith
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Martin Rex
- Re: [TLS] Cached-info substitution Adam Langley
- Re: [TLS] Cached-info substitution Brian Smith
- Re: [TLS] Cached-info substitution Adam Langley
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- Re: [TLS] Cached-info substitution Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Martin Rex
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Martin Rex
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Kemp, David P.
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Martin Rex
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Martin Rex
- [TLS] RFC 5077 (was Re: draft-ietf-tls-cached-inf… Michael D'Errico
- Re: [TLS] Cached-info substitution Adam Langley
- Re: [TLS] Cached-info substitution Wan-Teh Chang
- Re: [TLS] Cached-info substitution Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Simon Josefsson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Martin Rex
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Kemp, David P.
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Marsh Ray
- Re: [TLS] [POSSIBLE SPAM] Re: draft-ietf-tls-cach… Kemp, David P.
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Marsh Ray
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Yoav Nir
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Simon Josefsson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Martin Rex
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Simon Josefsson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Simon Josefsson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Joseph Salowey (jsalowey)
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Brian Smith
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Martin Rex
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Simon Josefsson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Donald Eastlake
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Joseph Salowey (jsalowey)
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Marsh Ray
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Simon Josefsson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Stefan Santesson
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Adam Langley
- Re: [TLS] draft-ietf-tls-cached-info-02 / New "Fa… Michael D'Errico