From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 94CF3F98; Wed, 2 Oct 2019 15:21:09 +0000 (UTC) X-Greylist: delayed 00:09:34 by SQLgrey-1.7.6 X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from ob1-4.mailhostbox.com (ob1-4.mailhostbox.com [162.222.225.13]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 1857C1FB; Wed, 2 Oct 2019 15:21:09 +0000 (UTC) Received: from [0.0.0.0] (tor.mailbox.org [80.241.60.207]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) (Authenticated sender: s7r@sky-ip.org) by outbound.mailhostbox.com (Postfix) with ESMTPSA id 703001A1289; Wed, 2 Oct 2019 15:11:32 +0000 (GMT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sky-ip.org; s=20110108; t=1570029094; bh=c1dpMOhuC6UuHI+cRA/BbnbePZivDMcPe9m2uN85/og=; h=Subject:To:Cc:References:From:Date:In-Reply-To; b=FWlf/Nr9hpOGgbxvJ/ei49+zV3d/04bG4hzQcAl1Gco686GW14rkwSzol10kDWD8x 6H3Pt/BhDOzsvJAb9H2A4vaOJq7+Nu/Nci+/h/kbhNnH9aq4IZ0YxCsmNCZP7TyEy3 BBAcgVQzLNgRV/xycEjDYBcM5eRtt1bNRwRmLlRA= To: Anthony Towns , Bitcoin Protocol Discussion , Christian Decker References: <87wodp7w9f.fsf@gmail.com> <20191001155929.e2yznsetqesx2jxo@erisian.com.au> From: s7r Openpgp: preference=signencrypt Autocrypt: addr=s7r@sky-ip.org; prefer-encrypt=mutual; keydata= mQENBE9BogQBCADazBiEe0PGTgeUJ/JU4BDvdE2ZFD+MUOgf3+n78F6mXTxcLgyiE/3E4rA5 Sy3NzVRjqjzyn/MyDJDbsRpSKT6uVT5thYNyfDNBNqYmqdVS8Gu+H90z78x1WJ+DxVawk4IM mi8jmKcwlz7hOGROsR0+NyWjyghlzNHVgiJkWIvp5AVDg4F6o2oCH/vBbgomu3Ho5r7fiRZg I0uxsMLIkRI8bwB3SlVi3n4a94ZI2R9rXD9KNWzW4OT5LnICW1d/cuktwVBQRxGE6KFtVDzI chjuDWFaT9p6qROqoBRbsGF/mLg/sb26dwRxb7CnxfCWJn10ZGWo8jG6MM/QKEcxSj0JABEB AAG0NHM3ckBza3ktaXAub3JnIChBbm9ueW1pdHkgbWF0dGVycyEpIDxzN3JAc2t5LWlwLm9y Zz6JATgEEwECACIFAk9BogQCGwMGCwkIBwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJEIN/pSyB JlsRbkQH/jfe6F9nbwwFBo2DuNJ+Ci2IpZEco1P6rWh2l3AzG0vOD82nYJ5uFIw+0v615tW8 WWNfeIsrbCRnmOAx8NGkGsk/j+SRJb41pQ79tyxdBg7txcbT9bAdcaImYoBBp+1bnyrAaROB 1wDq0jKX09ofKrrAUWOlddASpIBG5uKMLhHe1X14lmvgGHWDPHKrw4yzBN/nNfXYr+Ayjt9s NM6JETHIgqO6uvchiT20v2/SzD3FlysROkPeoFjGWUwAqH2r7RQyDLF6EoqkrcuwvjFXiOFE nFdNRbHQsKYXPhbk2JUiFQQcdLtJg6iaoRBnhATl4V6soP2EHYn3K1bz+eYL+AS5AQ0ET0Gi BAEIAMO7MGEfdMn72SQAK0m5rcEPj3mtSRRokMHl3YBNjFbj3O4QAwjpKBJ7RuPdF9B9IDAP a7mc+f33mpIgRnxKDwkjswPk74mMQRxe2wgv4AQ7yBICYYK99e6RYP0LC1PDIGXFPLjs0Teu QAxASFvNycC5JSfQUsAI3OTQjaGUaiUfavmJYkn9B6C2ktQgvM7qbxJvLP5X02tgp4G4gNiu 8ZA3aOUdX+8EQwERJZ8CuA/R6/2M2nEO3YRCsxaYSzob7nicjfoPvyvSYu3zXRFj+3uvDOK6 AGNILmftVUoRQ6/WsNaAQX42cDfSNYQ8uZ/zgTGatO3ArNb1uqWbMdbUA5sAEQEAAYkBHwQY AQIACQUCT0GiBAIbDAAKCRCDf6UsgSZbEZjSB/41TviTCxdiS4PLSDrQ3GOmQPpWZRk/O1tv 3y6T9p0XuC/oq6kKfToKuV2/Ok+589rtmrXhjzdk2otDKCRGejJFpVoU/vfR+jokArzpwyPa TWDAhMGmf5wmEAojsiOc9Zgj/CuS5nd/eLFi4QGtbLoDLrTrQSXB4qR0zJFoQfykVaERT2dm UV/D22opJc8jo3UBOBckgGi9jBi/2OvwEiFcZSl1u9Qi4+gbINOObQF5a0h9ReZCT1BUs5FV DSXBBYZTJJ2flnZH69Mb+9KxRMyqjhRzyGDUfY73SYlCpKX9buWMl0CCsDx+GrRVSxvQnA8b aSq1wlfKsJBimGtSAqf8 Message-ID: <51d80db6-83d9-2473-d007-f3601c940f28@sky-ip.org> Date: Wed, 2 Oct 2019 18:11:25 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <20191001155929.e2yznsetqesx2jxo@erisian.com.au> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="HEN1WAd7r7SYkV35VjmtYyeh0LCnwPFfs" X-CMAE-Score: 0 X-CMAE-Analysis: v=2.2 cv=X4YiECbe c=1 sm=1 tr=0 a=wxLzTxeQipeV3y8dd4rAPQ==:117 a=wxLzTxeQipeV3y8dd4rAPQ==:17 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=13zjGPudsaEWiJwPRgMA:9 a=7mUrSb40drMtBRZyxQ4A:9 a=pdR69DOaQzvPY8um:21 a=wmrNKXLhZEGbeWwC:21 a=QEXdDO2ut3YA:10 a=XD8RDNI9Z5C_sgb_vlYA:9 a=FfaGCDsud1wA:10 X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, 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: lightning-dev@lists.linuxfoundation.org Subject: Re: [bitcoin-dev] Continuing the discussion about noinput / anyprevout 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: Wed, 02 Oct 2019 15:21:09 -0000 This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --HEN1WAd7r7SYkV35VjmtYyeh0LCnwPFfs Content-Type: multipart/mixed; boundary="D1yworrtRopo0MAMctdVVLhkFtIsbt14G"; protected-headers="v1" From: s7r To: Anthony Towns , Bitcoin Protocol Discussion , Christian Decker Cc: lightning-dev@lists.linuxfoundation.org Message-ID: <51d80db6-83d9-2473-d007-f3601c940f28@sky-ip.org> Subject: Re: [bitcoin-dev] Continuing the discussion about noinput / anyprevout References: <87wodp7w9f.fsf@gmail.com> <20191001155929.e2yznsetqesx2jxo@erisian.com.au> In-Reply-To: <20191001155929.e2yznsetqesx2jxo@erisian.com.au> --D1yworrtRopo0MAMctdVVLhkFtIsbt14G Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable Anthony Towns via bitcoin-dev wrote: [SNIP] >=20 > My thinking at the moment (subject to change!) is: >=20 > * anyprevout signatures make the address you're signing for less safe,= > which may cause you to lose funds when additional coins are sent to > the same address; this can be avoided if handled with care (or if yo= u > don't care about losing funds in the event of address reuse) >=20 It's not necessarily like this. Address re-use is many times OUTSIDE the control of the address owner. Say I give my address to a counterparty. They send me a transaction which I successfully spend. So far so good. After that, I have no control over that counterparty. If they decide to re-use that address, it does not mean I wanted to re-use it and it also does not mean that I don't care about those funds being lost. This could create a lot of problems in the industry and I think it should be avoided. Address re-use has been strongly discouraged ever since I can remember, and all (proper) wallet implementations try as hard as possible to enforce it, but it's not always possible. A counterparty that decides to re-use an address, either accidentally or not, is not under the control of the user who handed out the address in the first place. There are also a lot of use cases with P2SH addresses that are some smart contracts particularly designed to be re-used multiple times over time. My 2 cents are that this is not a good way to go. If you try to index the entire blockchain until now you'll see that address re-use is more common than we'd want it to be and there's no clear way to prevent this from further happening without hurting the economic interests of the user= s. --D1yworrtRopo0MAMctdVVLhkFtIsbt14G-- --HEN1WAd7r7SYkV35VjmtYyeh0LCnwPFfs Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEfDaSMlq9+wswIQPxg3+lLIEmWxEFAl2UviEACgkQg3+lLIEm WxF2dggA2OYwiDXdQzrzPcDC4n8kT0S6yjFA819vYFJjv+fM4PtEArYjO6x8xqIv H3a79re4sXp+J2o5grGCkjXhWlVvqXh3k2LZ03PfXIOrdjAz5K8oE+gLqQ2Gpf5G jFkRxjzHui6a/nZX3irikl4Nn1Zh3V9X+5qPielafqsrWPXSq6U+onrNvWofcFfp FFJXsKh5g6Uw4+O5FrXfmJNY3Fj8kVa582nKAa3GTjgShlVrK73TbWzH3Q3wqo1+ qcRh1BXuryiNek4Qi5eIrgtM3NkFUk0ymhVGm9S35ToRSMQV5hfjtDZ//7K42rx3 KHWmea2MBDO8Lwqc50JPtn6eXwQKTA== =vndX -----END PGP SIGNATURE----- --HEN1WAd7r7SYkV35VjmtYyeh0LCnwPFfs--