Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 8C44317E4 for ; Tue, 19 Feb 2019 20:37:31 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from sender-of-o51.zoho.com (sender-of-o51.zoho.com [135.84.80.216]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 064078D for ; Tue, 19 Feb 2019 20:37:30 +0000 (UTC) ARC-Seal: i=1; a=rsa-sha256; t=1550608649; cv=none; d=zoho.com; s=zohoarc; b=fasNS2GOMlD381yukNVN4U0NfPls3b7WUF7aU90QLVjTQRViRMRq3Vo1tRbNz98p2x3LwzvgRsSvneERiWrg8g8gceFfWoUIhhMUCxz5mf3h291iIKV4DZ1P47AhoEqq9XXQ0McBrwyZNY206LIJQru39LXh4WTuqbz++szOauc= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1550608649; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:To:ARC-Authentication-Results; bh=uFWBPhdDCMtM2/JV/wvqRzG4lX/zrTuolZ96aChD2K8=; b=LPNchOV4oxERRGWF+79jmgvDspfP9uw4VsTTUT+q7cpDV1YbdYFipiDH4hGsSn9WEdOrwQA+2ePsN4p9nBt2I0cOIAURgpC3OVT07sxXXby5rzb94MuhOKwGgdsCm7iSC0ZLNND5bYapqPxR9DWZRt/G47G9Ivg2Kpmg8XMalng= ARC-Authentication-Results: i=1; mx.zoho.com; dkim=pass header.i=xbt.hk; spf=pass smtp.mailfrom=jl2012@xbt.hk; dmarc=pass header.from= header.from= Received: from [10.8.0.100] (n218103189223.netvigator.com [218.103.189.223]) by mx.zohomail.com with SMTPS id 1550608648281768.422468287698; Tue, 19 Feb 2019 12:37:28 -0800 (PST) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 12.0 \(3445.100.39\)) From: Johnson Lau In-Reply-To: <201902192024.13243.luke@dashjr.org> Date: Wed, 20 Feb 2019 04:36:51 +0800 Content-Transfer-Encoding: quoted-printable Message-Id: <9AFB2D9C-73E9-45F4-AB21-6899F55AAA94@xbt.hk> References: <9F8C0789-48E9-448A-A239-DB4AFB902A00@xbt.hk> <201902191904.04412.luke@dashjr.org> <201902192024.13243.luke@dashjr.org> To: Luke Dashjr X-Mailer: Apple Mail (2.3445.100.39) X-ZohoMailClient: External X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,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 X-Mailman-Approved-At: Wed, 06 Mar 2019 00:22:07 +0000 Cc: bitcoin-dev Subject: Re: [bitcoin-dev] Safer NOINPUT with output tagging X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 19 Feb 2019 20:37:31 -0000 > On 20 Feb 2019, at 4:24 AM, Luke Dashjr wrote: >=20 > Even besides NOINPUT, such a wallet would simply never show a second = payment=20 > to the same address (or at least never show it as confirmed, until=20 > successfully spent). This is totally unrelated to NOINPUT. You can make a wallet like this = today already, and tell your payer not to reuse address. >=20 > At least if tx versions are used, it isn't possible to indicate this=20= > requirement in current Bitcoin L1 addresses. scriptPubKey might not be=20= > impossible to encode, but it isn't really clear what the purpose of = doing so=20 > is. It sounds like you actually want to tag such outputs as scriptPubKey, so = you could encode this requirement in the address? If we allow NOINPUT unconditionally (i.e. all v1 addresses are spendable = with NOINPUT), you may only create a different proposal to indicate such = special requirements=20 >=20 > If people don't want to use NOINPUT, they should just not use it. = Trying to=20 > implement a nanny in the protocol is inappropriate and limits what = developers=20 > can do who actually want the features. >=20 > Luke >=20 >=20 > On Tuesday 19 February 2019 19:22:07 Johnson Lau wrote: >> This only depends on the contract between the payer and payee. If the >> contract says address reuse is unacceptable, it=E2=80=99s = unacceptable. It has >> nothing to do with how the payee spends the coin. We can=E2=80=99t = ban address >> reuse at protocol level (unless we never prune the chain), so address = reuse >> could only be prevented at social level. >>=20 >> Using NOINPUT is also a very weak excuse: NOINPUT always commit to = the >> value. If the payer reused an address but for different amount, the = payee >> can=E2=80=99t claim the coin is lost due to previous NOINPUT use. A = much stronger >> way is to publish the key after a coin is well confirmed. >>=20 >>> On 20 Feb 2019, at 3:04 AM, Luke Dashjr wrote: >>>=20 >>> On Thursday 13 December 2018 12:32:44 Johnson Lau via bitcoin-dev = wrote: >>>> While this seems fully compatible with eltoo, is there any other >>>> proposals require NOINPUT, and is adversely affected by either way = of >>>> tagging? >>>=20 >>> Yes, this seems to break the situation where a wallet wants to use >>> NOINPUT for everything, including normal L1 payments. For example, = in the >>> scenario where address reuse will be rejected/ignored by the = recipient >>> unconditionally, and the payee is considered to have burned their >>> bitcoins by attempting it. >>>=20 >>> Luke >=20