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Re: [pkix] Clarification on "zero" hash value in SigPolicyHash (CAdES)

Peter Gutmann <pgut001@cs.auckland.ac.nz> Wed, 17 July 2019 02:57 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: Niklas Matthies <pkix@nmhq.net>, "pkix@ietf.org" <pkix@ietf.org>
Thread-Topic: [pkix] Clarification on "zero" hash value in SigPolicyHash (CAdES)
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Date: Wed, 17 Jul 2019 02:57:08 +0000
Message-ID: <1563332225748.54393@cs.auckland.ac.nz>
References: <20190712200549.2kgzjqodj5afnxlt@nmhq.net> <0FDBEEC9-0FBA-4C47-BD04-EE7F6053426D@aaa-sec.com>, <20190716134215.txzqvcgghajh2es3@nmhq.net>
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Subject: Re: [pkix] Clarification on "zero" hash value in SigPolicyHash (CAdES)
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Niklas Matthies <pkix@nmhq.net> writes:

>All-bits-zero can conceivably be a valid hash value

If someone has a means of reaching not even all-zero-bits but just a
significant number of leading zero bits for a hash, please contact me off-
list, I have a very lucrative Bitcoin-based business proposition for you.

Peter.

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