From: Sjors Provoost <sjors@sprovoost.nl>
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Date: Sat, 9 Dec 2017 13:57:52 +0100
References: <CAAUFj10gEPBS3nTZ6aJn4UazhcJKPni6_pYGWwOs+QNeDo9NaA@mail.gmail.com>
To: Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>,
	DKBryant@gmail.com
In-Reply-To: <CAAUFj10gEPBS3nTZ6aJn4UazhcJKPni6_pYGWwOs+QNeDo9NaA@mail.gmail.com>
Message-Id: <69F75C75-6E51-4189-B3AE-032573B49A92@sprovoost.nl>
Subject: Re: [bitcoin-dev] Sign / Verify message against SegWit P2SH
 addresses.
Precedence: list


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I would like to see this specifically for P2SH-PWPKH and/or native =
SegWit bech32 addresses.

Use cases I can think of are "I'm the whale in charge of these funds, =
listen to me" and some form of polling.

It's nice if funds aren't excluded from these type of functionalities =
just because they have a complicated redeem script. So something more =
generic like the Elements implementation / suggestion Greg Maxwell =
referred to in the Github thread would be nice too.

Is it also useful or possible to sign a message proving you are able to =
redeem some arbitrary branch in a MAST-like tree of scripts? What about =
being a minority part of a multisig?

All these features have privacy trade-offs, as well as perhaps security =
trade-offs, e.g. when you reveal a public key that was otherwise hidden =
behind a hash (i.e. if someone were to break secp256k1, they'd first =
organize a popular poll).

There's no BIP for the current message signing mechanism either afaik.

Sjors

> Op 8 dec. 2017, om 19:25 heeft Dan Bryant via bitcoin-dev =
<bitcoin-dev@lists.linuxfoundation.org> het volgende geschreven:
>=20
> I know there are posts, and an issue opened against it, but is there =
anyone writing a BIP for Sign / Verify message against a SegWit address?
>=20
> I realize it is not a feature in wide use, but I think it still serves =
an important purpose, such as when proof of assets are requested.
>=20
> ref: https://github.com/bitcoin/bitcoin/issues/10542 =
<https://github.com/bitcoin/bitcoin/issues/10542>
>=20
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev


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<html><head><meta http-equiv=3D"Content-Type" content=3D"text/html; =
charset=3Dus-ascii"></head><body style=3D"word-wrap: break-word; =
-webkit-nbsp-mode: space; line-break: after-white-space;" class=3D"">I =
would like to see this specifically for&nbsp;P2SH-PWPKH and/or native =
SegWit bech32 addresses.<div class=3D""><br class=3D""></div><div =
class=3D"">Use cases I can think of are "I'm the whale in charge of =
these funds, listen to me" and some form of polling.</div><div =
class=3D""><br class=3D""></div><div class=3D"">It's nice if funds =
aren't excluded from these type of functionalities just because they =
have a complicated redeem script. So something more generic like the =
Elements implementation / suggestion Greg Maxwell referred to in the =
Github thread would be nice too.</div><div class=3D""><br =
class=3D""></div><div class=3D"">Is it also useful or possible to sign a =
message proving you are able to redeem some arbitrary branch in a =
MAST-like tree of scripts? What about being a minority part of a =
multisig?</div><div class=3D""><br class=3D""></div><div class=3D"">All =
these features have privacy trade-offs, as well as perhaps security =
trade-offs, e.g. when you reveal a public key that was otherwise hidden =
behind a hash (i.e. if someone were to break secp256k1, they'd first =
organize a popular poll).<br class=3D""><div class=3D""><br =
class=3D""></div><div class=3D"">There's no BIP for the current message =
signing mechanism either afaik.<br class=3D""><div class=3D""><br =
class=3D""></div><div class=3D"">Sjors<br class=3D""><div><br =
class=3D""><blockquote type=3D"cite" class=3D""><div class=3D"">Op 8 =
dec. 2017, om 19:25 heeft Dan Bryant via bitcoin-dev &lt;<a =
href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org" =
class=3D"">bitcoin-dev@lists.linuxfoundation.org</a>&gt; het volgende =
geschreven:</div><br class=3D"Apple-interchange-newline"><div =
class=3D""><div dir=3D"ltr" class=3D"">I know there are posts, and an =
issue opened against it, but is there anyone writing a BIP for Sign / =
Verify message against a SegWit address?<div class=3D""><br =
class=3D""></div><div class=3D"">I realize it is not a feature in wide =
use, but I think it still serves an important purpose, such as when =
proof of assets are requested.<br class=3D""><div class=3D""><br =
class=3D""></div><div class=3D"">ref:&nbsp;<a =
href=3D"https://github.com/bitcoin/bitcoin/issues/10542" =
class=3D"">https://github.com/bitcoin/bitcoin/issues/10542</a></div></div>=
<div class=3D""><br class=3D""></div></div>
_______________________________________________<br class=3D"">bitcoin-dev =
mailing list<br class=3D""><a =
href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org" =
class=3D"">bitcoin-dev@lists.linuxfoundation.org</a><br =
class=3D"">https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev<=
br class=3D""></div></blockquote></div><br =
class=3D""></div></div></div></body></html>=

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