Date: Mon, 9 Jul 2018 05:41:39 -0400
From: Peter Todd <pete@petertodd.org>
To: Gregory Maxwell <greg@xiph.org>
Message-ID: <20180709094139.wip4xqecjdjkqmjn@petertodd.org>
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Cc: Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>,
	lightning-dev@lists.linuxfoundation.org
Subject: Re: [bitcoin-dev] BIP sighash_noinput
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On Tue, Jul 03, 2018 at 11:45:22PM +0000, Gregory Maxwell wrote:
> On Tue, Jul 3, 2018 at 5:21 AM, Peter Todd <pete@petertodd.org> wrote:
> > The problem with that name is `SIGHASH_REUSE_VULNERABLE` tells you noth=
ing
> > about what the flag actually does.
>=20
> I believe that making the signature replayable is 1:1 with omitting
> the identification of the specific coin being spent from it.

I think you have a good point there. But that's not the only way that reuse
could be a vulnerability: consider hash-based signatures.

I'm happy with adding a suffix or prefix to the term SIGHASH_NOINPUT, e.g.
SIGHASH_NOINPUT_UNSAFE to re-use Rust terminology.

--=20
https://petertodd.org 'peter'[:-1]@petertodd.org

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