From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193] helo=mx.sourceforge.net) by sfs-ml-1.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1Yn2a8-00032v-Q4 for bitcoin-development@lists.sourceforge.net; Tue, 28 Apr 2015 10:17:36 +0000 Received-SPF: pass (sog-mx-3.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.212.171 as permitted sender) client-ip=209.85.212.171; envelope-from=oleganza@gmail.com; helo=mail-wi0-f171.google.com; Received: from mail-wi0-f171.google.com ([209.85.212.171]) by sog-mx-3.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1Yn2a7-0006n2-UH for bitcoin-development@lists.sourceforge.net; Tue, 28 Apr 2015 10:17:36 +0000 Received: by wizk4 with SMTP id k4so133963194wiz.1 for ; Tue, 28 Apr 2015 03:17:30 -0700 (PDT) X-Received: by 10.180.84.8 with SMTP id u8mr28750155wiy.39.1430216249887; Tue, 28 Apr 2015 03:17:29 -0700 (PDT) Received: from ?IPv6:2a01:e35:8a2c:a630:4014:f754:25b0:da9a? ([2a01:e35:8a2c:a630:4014:f754:25b0:da9a]) by mx.google.com with ESMTPSA id ha4sm15681558wib.0.2015.04.28.03.17.28 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 28 Apr 2015 03:17:28 -0700 (PDT) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2098\)) From: Oleg Andreev In-Reply-To: <20150427191855.GE5223@muck> Date: Tue, 28 Apr 2015 12:17:27 +0200 Content-Transfer-Encoding: quoted-printable Message-Id: <3B4C8493-CD37-4D43-ABF1-0AA5388CD78E@gmail.com> References: <552EF785.7000207@sky-ip.org> <552FDF73.6010104@sky-ip.org> <20150427191855.GE5223@muck> To: Peter Todd X-Mailer: Apple Mail (2.2098) X-Spam-Score: -1.6 (-) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (oleganza[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature X-Headers-End: 1Yn2a7-0006n2-UH Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] 75%/95% threshold for transaction versions X-BeenThere: bitcoin-development@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 28 Apr 2015 10:17:36 -0000 > On 27 Apr 2015, at 21:21, Peter Todd wrote: >=20 > Even right now there are edge cases without > good solutions, like how in a multisig environment any of the key > holders can mutate transactions. Can't we add requirement for RFC6979 signatures to mitigate this? Of = course, multiple signers can still mutate transaction by choosing a = different set (but not the order, thankfully) of signatures. Or when a = single signer has multiple participating keys. In some interesting to me scenarios mutation by signer is not critical: = it is mutation by non-signers that creates a problem. Do you know of any = edge cases when non-signers can mutate transactions which are not = covered by BIP62? What would be a more robust approach than = "whack-a-mole" to work around mutability? (Normalized tx ids?)=