Return-Path: <jl2012@xbt.hk> Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 7A2EA957 for <bitcoin-dev@lists.linuxfoundation.org>; Tue, 9 May 2017 17:56:37 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from sender-of-o52.zoho.com (sender-of-o52.zoho.com [135.84.80.217]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 6B3A01D8 for <bitcoin-dev@lists.linuxfoundation.org>; Tue, 9 May 2017 17:56:36 +0000 (UTC) Received: from [10.8.8.2] (119246245241.ctinets.com [119.246.245.241]) by mx.zohomail.com with SMTPS id 1494352592543758.1537345238635; Tue, 9 May 2017 10:56:32 -0700 (PDT) From: Johnson Lau <jl2012@xbt.hk> Message-Id: <BBB06F5F-4AC4-4FFD-AD1C-5304140E56C6@xbt.hk> Content-Type: multipart/alternative; boundary="Apple-Mail=_65CBB807-ADD2-4F85-94BA-25868159BF79" Mime-Version: 1.0 (Mac OS X Mail 10.2 \(3259\)) Date: Wed, 10 May 2017 01:56:28 +0800 In-Reply-To: <20170509005659.GA1902@gmail.com> To: Christopher Jeffrey <chjj@purse.io> References: <20170405174343.GA7180@gmail.com> <F322F899-8748-407D-884F-95EFBD3C7F99@xbt.hk> <20170509005659.GA1902@gmail.com> X-Mailer: Apple Mail (2.3259) X-ZohoMailClient: External X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,HTML_MESSAGE, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Cc: bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org> Subject: Re: [bitcoin-dev] Extension block proposal by Jeffrey et al X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Protocol Discussion <bitcoin-dev.lists.linuxfoundation.org> List-Unsubscribe: <https://lists.linuxfoundation.org/mailman/options/bitcoin-dev>, <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=unsubscribe> List-Archive: <http://lists.linuxfoundation.org/pipermail/bitcoin-dev/> List-Post: <mailto:bitcoin-dev@lists.linuxfoundation.org> List-Help: <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=help> List-Subscribe: <https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev>, <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=subscribe> X-List-Received-Date: Tue, 09 May 2017 17:56:37 -0000 --Apple-Mail=_65CBB807-ADD2-4F85-94BA-25868159BF79 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii To make it completely transparent to unupgraded wallets, the return = outputs have to be sent to something that is non-standard today, i.e. = not P2PK, P2PKH, P2SH, bare multi-sig, and (with BIP141) v0 P2WPKH and = v0 P2WSH. Mainchain segwit is particularly important here, as that allows atomic = swap between the bitcoin and xbitcoin. Only services with high liquidity = (exchanges, payment processors) would need to occasionally settle = between the chains. > On 9 May 2017, at 08:56, Christopher Jeffrey <chjj@purse.io> wrote: >=20 > Johnson, >=20 > Yeah, I do still see the issue. I think there are still some = reasonable > ways to mitigate it. >=20 > I've started revising the extension block specification/code to = coexist > with mainchain segwit. I think the benefit of this is that we can > require exiting outputs to only be witness programs. Presumably segwit > wallets will be more likely to be aware of a new output maturity rule > (I've opened a PR[1] which describes this in greater detail). I think > this probably reduces the likelihood of the legacy wallet issue, > assuming most segwit-supporting wallets would implement this rule = before > the activation of segwit. >=20 > What's your opinion on whether this would have a great enough effect = to > prevent the legacy wallet issue? I think switching to witness programs > only may be a good balance between fungibility and backward-compat, > probably better all around than creating a whole new > addr-type/wit-program just for exits. >=20 > [1] https://github.com/tothemoon-org/extension-blocks/pull/16 = <https://github.com/tothemoon-org/extension-blocks/pull/16> >=20 --Apple-Mail=_65CBB807-ADD2-4F85-94BA-25868159BF79 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=us-ascii <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; -webkit-line-break: after-white-space;" = class=3D""><div class=3D"">To make it completely transparent to = unupgraded wallets, the return outputs have to be sent to something that = is non-standard today, i.e. not P2PK, P2PKH, P2SH, bare multi-sig, and = (with BIP141) v0 P2WPKH and v0 P2WSH.</div><div class=3D""><br = class=3D""></div><div class=3D"">Mainchain segwit is particularly = important here, as that allows atomic swap between the bitcoin and = xbitcoin. Only services with high liquidity (exchanges, payment = processors) would need to occasionally settle between the = chains.</div><div class=3D""><br class=3D""></div><br = class=3D""><div><blockquote type=3D"cite" class=3D""><div class=3D"">On = 9 May 2017, at 08:56, Christopher Jeffrey <<a = href=3D"mailto:chjj@purse.io" class=3D"">chjj@purse.io</a>> = wrote:</div><br class=3D"Apple-interchange-newline"><div class=3D""><span = style=3D"font-family: Helvetica; font-size: 12px; font-style: normal; = font-variant-caps: normal; font-weight: normal; letter-spacing: normal; = orphans: auto; text-align: start; text-indent: 0px; text-transform: = none; white-space: normal; widows: auto; word-spacing: 0px; = -webkit-text-stroke-width: 0px; float: none; display: inline = !important;" class=3D"">Johnson,</span><br style=3D"font-family: = Helvetica; font-size: 12px; font-style: normal; font-variant-caps: = normal; font-weight: normal; letter-spacing: normal; orphans: auto; = text-align: start; text-indent: 0px; text-transform: none; white-space: = normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: = 0px;" class=3D""><br style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=3D""><span = style=3D"font-family: Helvetica; font-size: 12px; font-style: normal; = font-variant-caps: normal; font-weight: normal; letter-spacing: normal; = orphans: auto; text-align: start; text-indent: 0px; text-transform: = none; white-space: normal; widows: auto; word-spacing: 0px; = -webkit-text-stroke-width: 0px; float: none; display: inline = !important;" class=3D"">Yeah, I do still see the issue. I think there = are still some reasonable</span><br style=3D"font-family: Helvetica; = font-size: 12px; font-style: normal; font-variant-caps: normal; = font-weight: normal; letter-spacing: normal; orphans: auto; text-align: = start; text-indent: 0px; text-transform: none; white-space: normal; = widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" = class=3D""><span style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: = inline !important;" class=3D"">ways to mitigate it.</span><br = style=3D"font-family: Helvetica; font-size: 12px; font-style: normal; = font-variant-caps: normal; font-weight: normal; letter-spacing: normal; = orphans: auto; text-align: start; text-indent: 0px; text-transform: = none; white-space: normal; widows: auto; word-spacing: 0px; = -webkit-text-stroke-width: 0px;" class=3D""><br style=3D"font-family: = Helvetica; font-size: 12px; font-style: normal; font-variant-caps: = normal; font-weight: normal; letter-spacing: normal; orphans: auto; = text-align: start; text-indent: 0px; text-transform: none; white-space: = normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: = 0px;" class=3D""><span style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: = inline !important;" class=3D"">I've started revising the extension block = specification/code to coexist</span><br style=3D"font-family: Helvetica; = font-size: 12px; font-style: normal; font-variant-caps: normal; = font-weight: normal; letter-spacing: normal; orphans: auto; text-align: = start; text-indent: 0px; text-transform: none; white-space: normal; = widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" = class=3D""><span style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: = inline !important;" class=3D"">with mainchain segwit. I think the = benefit of this is that we can</span><br style=3D"font-family: = Helvetica; font-size: 12px; font-style: normal; font-variant-caps: = normal; font-weight: normal; letter-spacing: normal; orphans: auto; = text-align: start; text-indent: 0px; text-transform: none; white-space: = normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: = 0px;" class=3D""><span style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: = inline !important;" class=3D"">require exiting outputs to only be = witness programs. Presumably segwit</span><br style=3D"font-family: = Helvetica; font-size: 12px; font-style: normal; font-variant-caps: = normal; font-weight: normal; letter-spacing: normal; orphans: auto; = text-align: start; text-indent: 0px; text-transform: none; white-space: = normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: = 0px;" class=3D""><span style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: = inline !important;" class=3D"">wallets will be more likely to be aware = of a new output maturity rule</span><br style=3D"font-family: Helvetica; = font-size: 12px; font-style: normal; font-variant-caps: normal; = font-weight: normal; letter-spacing: normal; orphans: auto; text-align: = start; text-indent: 0px; text-transform: none; white-space: normal; = widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" = class=3D""><span style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: = inline !important;" class=3D"">(I've opened a PR[1] which describes this = in greater detail). I think</span><br style=3D"font-family: Helvetica; = font-size: 12px; font-style: normal; font-variant-caps: normal; = font-weight: normal; letter-spacing: normal; orphans: auto; text-align: = start; text-indent: 0px; text-transform: none; white-space: normal; = widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" = class=3D""><span style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: = inline !important;" class=3D"">this probably reduces the likelihood of = the legacy wallet issue,</span><br style=3D"font-family: Helvetica; = font-size: 12px; font-style: normal; font-variant-caps: normal; = font-weight: normal; letter-spacing: normal; orphans: auto; text-align: = start; text-indent: 0px; text-transform: none; white-space: normal; = widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" = class=3D""><span style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: = inline !important;" class=3D"">assuming most segwit-supporting wallets = would implement this rule before</span><br style=3D"font-family: = Helvetica; font-size: 12px; font-style: normal; font-variant-caps: = normal; font-weight: normal; letter-spacing: normal; orphans: auto; = text-align: start; text-indent: 0px; text-transform: none; white-space: = normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: = 0px;" class=3D""><span style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: = inline !important;" class=3D"">the activation of segwit.</span><br = style=3D"font-family: Helvetica; font-size: 12px; font-style: normal; = font-variant-caps: normal; font-weight: normal; letter-spacing: normal; = orphans: auto; text-align: start; text-indent: 0px; text-transform: = none; white-space: normal; widows: auto; word-spacing: 0px; = -webkit-text-stroke-width: 0px;" class=3D""><br style=3D"font-family: = Helvetica; font-size: 12px; font-style: normal; font-variant-caps: = normal; font-weight: normal; letter-spacing: normal; orphans: auto; = text-align: start; text-indent: 0px; text-transform: none; white-space: = normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: = 0px;" class=3D""><span style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: = inline !important;" class=3D"">What's your opinion on whether this would = have a great enough effect to</span><br style=3D"font-family: Helvetica; = font-size: 12px; font-style: normal; font-variant-caps: normal; = font-weight: normal; letter-spacing: normal; orphans: auto; text-align: = start; text-indent: 0px; text-transform: none; white-space: normal; = widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" = class=3D""><span style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: = inline !important;" class=3D"">prevent the legacy wallet issue? I think = switching to witness programs</span><br style=3D"font-family: Helvetica; = font-size: 12px; font-style: normal; font-variant-caps: normal; = font-weight: normal; letter-spacing: normal; orphans: auto; text-align: = start; text-indent: 0px; text-transform: none; white-space: normal; = widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" = class=3D""><span style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: = inline !important;" class=3D"">only may be a good balance between = fungibility and backward-compat,</span><br style=3D"font-family: = Helvetica; font-size: 12px; font-style: normal; font-variant-caps: = normal; font-weight: normal; letter-spacing: normal; orphans: auto; = text-align: start; text-indent: 0px; text-transform: none; white-space: = normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: = 0px;" class=3D""><span style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: = inline !important;" class=3D"">probably better all around than creating = a whole new</span><br style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=3D""><span = style=3D"font-family: Helvetica; font-size: 12px; font-style: normal; = font-variant-caps: normal; font-weight: normal; letter-spacing: normal; = orphans: auto; text-align: start; text-indent: 0px; text-transform: = none; white-space: normal; widows: auto; word-spacing: 0px; = -webkit-text-stroke-width: 0px; float: none; display: inline = !important;" class=3D"">addr-type/wit-program just for exits.</span><br = style=3D"font-family: Helvetica; font-size: 12px; font-style: normal; = font-variant-caps: normal; font-weight: normal; letter-spacing: normal; = orphans: auto; text-align: start; text-indent: 0px; text-transform: = none; white-space: normal; widows: auto; word-spacing: 0px; = -webkit-text-stroke-width: 0px;" class=3D""><br style=3D"font-family: = Helvetica; font-size: 12px; font-style: normal; font-variant-caps: = normal; font-weight: normal; letter-spacing: normal; orphans: auto; = text-align: start; text-indent: 0px; text-transform: none; white-space: = normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: = 0px;" class=3D""><span style=3D"font-family: Helvetica; font-size: 12px; = font-style: normal; font-variant-caps: normal; font-weight: normal; = letter-spacing: normal; orphans: auto; text-align: start; text-indent: = 0px; text-transform: none; white-space: normal; widows: auto; = word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: = inline !important;" class=3D"">[1]<span = class=3D"Apple-converted-space"> </span></span><a = href=3D"https://github.com/tothemoon-org/extension-blocks/pull/16" = style=3D"font-family: Helvetica; font-size: 12px; font-style: normal; = font-variant-caps: normal; font-weight: normal; letter-spacing: normal; = orphans: auto; text-align: start; text-indent: 0px; text-transform: = none; white-space: normal; widows: auto; word-spacing: 0px; = -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;" = class=3D"">https://github.com/tothemoon-org/extension-blocks/pull/16</a><b= r style=3D"font-family: Helvetica; font-size: 12px; font-style: normal; = font-variant-caps: normal; font-weight: normal; letter-spacing: normal; = orphans: auto; text-align: start; text-indent: 0px; text-transform: = none; white-space: normal; widows: auto; word-spacing: 0px; = -webkit-text-stroke-width: 0px;" class=3D""><br style=3D"font-family: = Helvetica; font-size: 12px; font-style: normal; font-variant-caps: = normal; font-weight: normal; letter-spacing: normal; orphans: auto; = text-align: start; text-indent: 0px; text-transform: none; white-space: = normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: = 0px;" class=3D""></div></blockquote></div><br class=3D""></body></html>= --Apple-Mail=_65CBB807-ADD2-4F85-94BA-25868159BF79--