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In-Reply-To: <725C679B-60E2-4E21-9F7D-10F67118D58D@friedenbach.org>
From: Jason Dreyzehner <jason@dreyzehner.com>
Date: Thu, 21 Dec 2017 17:23:49 +0000
Message-ID: <CALunu-GWw1P6BJ8sZdr1ApKJVHawd7LJ9JHfEWP-Z0nacc8bhg@mail.gmail.com>
To: Mark Friedenbach <mark@friedenbach.org>, 
	Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
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Subject: Re: [bitcoin-dev] Sign / Verify message against SegWit P2SH
	addresses.
Precedence: list

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You might be interested in this proposal, which is very similar. The repo
contains a very basic implementation in typescript:
https://github.com/bitauth/bitauth2017/blob/master/bips/0-bitauth.mediawiki

https://github.com/bitauth/bitauth2017/

On Tue, Dec 19, 2017 at 4:59 PM Mark Friedenbach via bitcoin-dev <
bitcoin-dev@lists.linuxfoundation.org> wrote:

> For what it=E2=80=99s worth, I think it would be quite easy to do better =
than the
> implied solution of rejiggering the message signing system to support
> non-P2PKH scripts. Instead, have the signature be an actual bitcoin
> transaction with inputs that have the script being signed. Use the salted
> hash of the message being signed as the FORKID as if this were a spin-off
> with replay protection. This accomplishes three things:
>
> (1) This enables signing by any infrastructure out there =E2=80=94 includ=
ing
> hardware wallets and 2FA signing services =E2=80=94 that have enabled sup=
port for
> FORKID signing, which is a wide swath of the ecosystem because of Bitcoin
> Cash and Bitcoin Gold.
>
> (2) It generalizes the message signing to allow multi-party signing setup=
s
> as complicated (via sighash, etc.) as those bitcoin transactions allow,
> using existing and future tools based on Partially Signed Bitcoin
> Transactions; and
>
> (3) It unifies a single approach for message signing, proof of reserve
> (where the inputs are actual UTXOs), and off-chain colored coins.
>
> There=E2=80=99s the issue of size efficiency, but for the single-party me=
ssage
> signing application that can be handled by a BIP that specifies a templat=
e
> for constructing the pseudo-transaction and its inputs from a raw script.
>
> Mark
>
> > On Dec 19, 2017, at 1:36 PM, Pavol Rusnak via bitcoin-dev <
> bitcoin-dev@lists.linuxfoundation.org> wrote:
> >
> > On 08/12/17 19:25, Dan Bryant via bitcoin-dev wrote:
> >> 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 addres=
s?
> >
> > Dan, are you still planning to write this BIP?
> >
> > --
> > Best Regards / S pozdravom,
> >
> > Pavol "stick" Rusnak
> > CTO, SatoshiLabs
> > _______________________________________________
> > bitcoin-dev mailing list
> > bitcoin-dev@lists.linuxfoundation.org
> > https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>

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<div dir=3D"ltr">You might be interested in this proposal, which is very si=
milar. The repo contains a very basic implementation in typescript:=C2=A0<a=
 href=3D"https://github.com/bitauth/bitauth2017/blob/master/bips/0-bitauth.=
mediawiki">https://github.com/bitauth/bitauth2017/blob/master/bips/0-bitaut=
h.mediawiki</a><div><br></div><div><a href=3D"https://github.com/bitauth/bi=
tauth2017/">https://github.com/bitauth/bitauth2017/</a>=C2=A0<br><br><div c=
lass=3D"gmail_quote"><div dir=3D"ltr">On Tue, Dec 19, 2017 at 4:59 PM Mark =
Friedenbach via bitcoin-dev &lt;<a href=3D"mailto:bitcoin-dev@lists.linuxfo=
undation.org">bitcoin-dev@lists.linuxfoundation.org</a>&gt; wrote:<br></div=
><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1=
px #ccc solid;padding-left:1ex">For what it=E2=80=99s worth, I think it wou=
ld be quite easy to do better than the implied solution of rejiggering the =
message signing system to support non-P2PKH scripts. Instead, have the sign=
ature be an actual bitcoin transaction with inputs that have the script bei=
ng signed. Use the salted hash of the message being signed as the FORKID as=
 if this were a spin-off with replay protection. This accomplishes three th=
ings:<br>
<br>
(1) This enables signing by any infrastructure out there =E2=80=94 includin=
g hardware wallets and 2FA signing services =E2=80=94 that have enabled sup=
port for FORKID signing, which is a wide swath of the ecosystem because of =
Bitcoin Cash and Bitcoin Gold.<br>
<br>
(2) It generalizes the message signing to allow multi-party signing setups =
as complicated (via sighash, etc.) as those bitcoin transactions allow, usi=
ng existing and future tools based on Partially Signed Bitcoin Transactions=
; and<br>
<br>
(3) It unifies a single approach for message signing, proof of reserve (whe=
re the inputs are actual UTXOs), and off-chain colored coins.<br>
<br>
There=E2=80=99s the issue of size efficiency, but for the single-party mess=
age signing application that can be handled by a BIP that specifies a templ=
ate for constructing the pseudo-transaction and its inputs from a raw scrip=
t.<br>
<br>
Mark<br>
<br>
&gt; On Dec 19, 2017, at 1:36 PM, Pavol Rusnak via bitcoin-dev &lt;<a href=
=3D"mailto:bitcoin-dev@lists.linuxfoundation.org" target=3D"_blank">bitcoin=
-dev@lists.linuxfoundation.org</a>&gt; wrote:<br>
&gt;<br>
&gt; On 08/12/17 19:25, Dan Bryant via bitcoin-dev wrote:<br>
&gt;&gt; I know there are posts, and an issue opened against it, but is the=
re<br>
&gt;&gt; anyone writing a BIP for Sign / Verify message against a SegWit ad=
dress?<br>
&gt;<br>
&gt; Dan, are you still planning to write this BIP?<br>
&gt;<br>
&gt; --<br>
&gt; Best Regards / S pozdravom,<br>
&gt;<br>
&gt; Pavol &quot;stick&quot; Rusnak<br>
&gt; CTO, SatoshiLabs<br>
&gt; _______________________________________________<br>
&gt; bitcoin-dev mailing list<br>
&gt; <a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org" target=3D"_bl=
ank">bitcoin-dev@lists.linuxfoundation.org</a><br>
&gt; <a href=3D"https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-=
dev" rel=3D"noreferrer" target=3D"_blank">https://lists.linuxfoundation.org=
/mailman/listinfo/bitcoin-dev</a><br>
<br>
_______________________________________________<br>
bitcoin-dev mailing list<br>
<a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org" target=3D"_blank">=
bitcoin-dev@lists.linuxfoundation.org</a><br>
<a href=3D"https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev" =
rel=3D"noreferrer" target=3D"_blank">https://lists.linuxfoundation.org/mail=
man/listinfo/bitcoin-dev</a><br>
</blockquote></div></div></div>

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