From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1YEhTI-0007AZ-NW for bitcoin-development@lists.sourceforge.net; Fri, 23 Jan 2015 16:52:36 +0000 Received-SPF: pass (sog-mx-2.v43.ch3.sourceforge.com: domain of gmail.com designates 74.125.82.170 as permitted sender) client-ip=74.125.82.170; envelope-from=gmaxwell@gmail.com; helo=mail-we0-f170.google.com; Received: from mail-we0-f170.google.com ([74.125.82.170]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1YEhTH-0001Yx-Js for bitcoin-development@lists.sourceforge.net; Fri, 23 Jan 2015 16:52:36 +0000 Received: by mail-we0-f170.google.com with SMTP id x3so8659695wes.1 for ; Fri, 23 Jan 2015 08:52:29 -0800 (PST) MIME-Version: 1.0 X-Received: by 10.180.205.163 with SMTP id lh3mr5522584wic.63.1422031949002; Fri, 23 Jan 2015 08:52:29 -0800 (PST) Received: by 10.27.11.170 with HTTP; Fri, 23 Jan 2015 08:52:28 -0800 (PST) In-Reply-To: References: <54C267A1.8090208@gmail.com> Date: Fri, 23 Jan 2015 16:52:28 +0000 Message-ID: From: Gregory Maxwell To: slush Content-Type: text/plain; charset=UTF-8 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 (gmaxwell[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: 1YEhTH-0001Yx-Js Cc: Bitcoin Development Subject: Re: [Bitcoin-development] SIGHASH_WITHINPUTVALUE 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: Fri, 23 Jan 2015 16:52:36 -0000 On Fri, Jan 23, 2015 at 4:18 PM, slush wrote: > Can you send me any reference about this? Of course if that solves the > problem, hard fork would not be necessary anymore. I'm just not aware of > any. Sure; will aggregate up the citations when I'm not travling later today. > To sign transaction with hundreds of inputs on device with limited memory > capabilities, I need to stream all previous transactions into device, for > every signed input. > > That means roughly 200^2 transaction verifications for 200 inputs to sign. > Very slow, but does not limit the device for any particular size of signed > transaction. I'm not sure where the ^2 is coming from. So what I'd understand that you'd do is stream in the input txid:vouts which you spend, then you'd stream the actual inputs which would just be hashed and value extracted (but no other verification), and you'd build a table of txid:vout->value, then the actual transaction to be signed. This should have O(inputs) hashing and communications overhead. Is there a step I'm missing?