Date: Thu, 14 Mar 2019 05:22:59 +0000
To: Anthony Towns <aj@erisian.com.au>
From: ZmnSCPxj <ZmnSCPxj@protonmail.com>
Reply-To: ZmnSCPxj <ZmnSCPxj@protonmail.com>
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Cc: "bitcoin-dev@lists.linuxfoundation.org"
	<bitcoin-dev@lists.linuxfoundation.org>,
	"lightning-dev@lists.linuxfoundation.org"
	<lightning-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] [Lightning-dev] More thoughts on NOINPUT safety
Precedence: list

Good morning aj,

When reading through your original post I saw you mentioned something about=
 output tagging somehow conflicting with Taproot, so I assumed Taproot is n=
ot useable in this case.
However, it is probably more likely that I simply misunderstood what you sa=
id, so if you can definitively say that it would be possible to hide the cl=
ause "or a NOINPUT sig from A with a non-NOINPUT sig from B" behind a Tapro=
ot then I am fine.

Minor pointless reactions:

> 5.  if you're using scriptless scripts to do HTLCs, you'll need to
>     allow for NOINPUT sigs when claiming funds as well (and update
>     the partial signatures for the non-NOINPUT cases if you want to
>     maximise privacy), which is a bit fiddly

If I remember accurately, we do not allow bilateral/cooperative close when =
HTLC is in-flight.
However, I notice that later you point out that a non-cheating unilateral c=
lose does not need NOINPUT, so I suppose. the above thought applies to that=
 case.


Regards,
ZmnSCPxj