Re: [openpgp] Deprecate legacy hash algorithms

Hanno Böck <hanno@hboeck.de> Fri, 17 March 2017 15:05 UTC

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Date: Fri, 17 Mar 2017 16:05:30 +0100
From: Hanno Böck <hanno@hboeck.de>
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Subject: Re: [openpgp] Deprecate legacy hash algorithms
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On Fri, 17 Mar 2017 10:00:10 +0100
Werner Koch <wk@gnupg.org> wrote:

>   Implementations MUST implement SHA-256.  Implementations MAY
> implement other algorithms.  Implementations MUST NOT create messages
> which require the use of SHA-1 with the exception of computing
> version 4 key fingerprints and for purposes of the MDC packet.
> Implementations MUST NOT use MD5 or RIPE-MD/160.

I'm wondering: Should there be a clearer distinction that this is for
creation of messages?

Because for verification I feel supporting bad algorithms is still
okay. Like if I want to verify a signature done with md5 it makes sense
that I'm able to do that. Ideally that would include a warning ("This
message was sigend with a weak hash alg"), but not supporting it
doesn't seem right.

-- 
Hanno Böck
https://hboeck.de/

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