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Re: [dmarc-ietf] WGLC ARC-16 concern on Section 5.1.2 - cv=fail should sign greedily

"John R Levine" <johnl@taugh.com> Fri, 17 August 2018 22:13 UTC

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Date: Fri, 17 Aug 2018 18:13:33 -0400
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From: John R Levine <johnl@taugh.com>
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Subject: Re: [dmarc-ietf] WGLC ARC-16 concern on Section 5.1.2 - cv=fail should sign greedily
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> I'm still at a bit of a loss as to how one can effectively do a "greedy"
> seal over a broken chain in a deterministic fashion.

I've been discussing this with Seth.  Particularly once we start doing 
parallel chains for different algorithms, different implementations will 
disagree about what's a broken chain, so I'd just as soon not try.

If the previous seal was good, add cv=fail only signing your own seal.  If 
the previous seal was cv=fail, don't sign.

Regards,
John Levine, johnl@taugh.com, Taughannock Networks, Trumansburg NY
Please consider the environment before reading this e-mail. https://jl.ly

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