Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1WDKHF-0004Ui-5A for bitcoin-development@lists.sourceforge.net; Tue, 11 Feb 2014 20:49:57 +0000 Received-SPF: pass (sog-mx-4.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.217.178 as permitted sender) client-ip=209.85.217.178; envelope-from=gmaxwell@gmail.com; helo=mail-lb0-f178.google.com; Received: from mail-lb0-f178.google.com ([209.85.217.178]) by sog-mx-4.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1WDKHE-0007gz-7J for bitcoin-development@lists.sourceforge.net; Tue, 11 Feb 2014 20:49:57 +0000 Received: by mail-lb0-f178.google.com with SMTP id u14so6304858lbd.37 for ; Tue, 11 Feb 2014 12:49:49 -0800 (PST) MIME-Version: 1.0 X-Received: by 10.112.148.104 with SMTP id tr8mr2576517lbb.62.1392151789579; Tue, 11 Feb 2014 12:49:49 -0800 (PST) Received: by 10.112.198.34 with HTTP; Tue, 11 Feb 2014 12:49:49 -0800 (PST) In-Reply-To: References: <20140210144003.2BDCCDDAEFC@quidecco.de> <20140210163055.GJ3180@nl.grid.coop> <20140210182506.GM3180@nl.grid.coop> <52F91E66.6060305@gmail.com> <20140210190703.GO3180@nl.grid.coop> <20140210192308.GA17359@savin> <20140210194032.GD17359@savin> <52F9377D.9010405@gmail.com> Date: Tue, 11 Feb 2014 12:49:49 -0800 Message-ID: From: Gregory Maxwell To: naman naman 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: 1WDKHE-0007gz-7J Cc: Bitcoin Development , Vocatus Gate Subject: Re: [Bitcoin-development] MtGox blames bitcoin 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, 11 Feb 2014 20:49:57 -0000 On Tue, Feb 11, 2014 at 12:42 PM, naman naman wrote: > I was talking about a DOS attack in > https://bitcointalk.org/index.php?topic=458608.0 (ofcourse only applicable > to entitys doing the tracking with txids). > > Amazing how I did not get a response from any of the devs (except Greg's > response > https://bitcointalk.org/index.php?topic=458608.msg5063789#msg5063789 but > that too was short and not concerning the attack scenario plausibiity as I > replied to him). Try paying a consultant if your ego demands that you have a technical expert to entertain your musing with immediate response. My response was absolutely relevant. If you reissue a transaction without respending the prior transactions coins, you will end up double paying. Only spending the inputs in question can prevent the prior transaction (itself or in other form) from going through. Once you respend the inputs there is no risk of actually losing funds due to an issue regardless of how you track coins in your higher level application.