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Re: [openpgp] V5 Fingerprint again

Thijs van Dijk <schnabbel@inurbanus.nl> Wed, 01 March 2017 19:42 UTC

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From: Thijs van Dijk <schnabbel@inurbanus.nl>
Date: Wed, 01 Mar 2017 20:42:35 +0100
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To: KellerFuchs <KellerFuchs@hashbang.sh>
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Subject: Re: [openpgp] V5 Fingerprint again
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>
> > ###V5 Fingerprint value calculation
> >
> > The OpenPGP V5 fingerprint value is calculated as follows
> >
> > Fingerprint = <Version-ID> + H (<Content-ID>  + ‘:’ + H(<data>))
>
> Why a colon, rather than a NUL byte?
> (It's not obvious that Content-Type strings, esp. auxiliary parameters,
>  cannot contain colons)


Well, if it helps: if you look closely, the data is hashed twice, once
without the content ID and a second time with content ID prepended, so
there's no chance of ambiguity, if that's what you were worried about.
Anything from the question of "should there be any separator at all?"
onwards is a matter of personal preference, really.

-Thijs

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