Re: [dane] Feature creep for draft-ietf-dane-smime

Viktor Dukhovni <viktor1dane@dukhovni.org> Fri, 07 February 2014 19:49 UTC

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From: Viktor Dukhovni <viktor1dane@dukhovni.org>
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Subject: Re: [dane] Feature creep for draft-ietf-dane-smime
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On Fri, Feb 07, 2014 at 11:08:20AM -0800, Paul Hoffman wrote:

> Those existed 15 years ago, and still do. The proposal to make
> it slightly harder for a harvester (and that's all we're suggesting)
> adds complexity and no measurable value.

Yes, adding iterations would definitely add complexity.

Arguably HMAC(domain, localpart) is more complex than
SHA(localpart@domain), I don't care which is used.

Either way of computing the hash of the full address, rather than
just the local part adds no complexity, and makes off-line attacks
more difficult (per site dictionaries, rather than global dictionaries).
This is a free win.  There's simply no reason not to.

-- 
	Viktor.