Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 65E72A48 for ; Tue, 28 Jun 2016 22:00:02 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-wm0-f48.google.com (mail-wm0-f48.google.com [74.125.82.48]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 343E4140 for ; Tue, 28 Jun 2016 21:59:58 +0000 (UTC) Received: by mail-wm0-f48.google.com with SMTP id f126so157204873wma.1 for ; Tue, 28 Jun 2016 14:59:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=voskuil-org.20150623.gappssmtp.com; s=20150623; h=mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=n93r+1hk3C/7yvzA9F2/n1lJlZFVvO8fgbioy7xNIv8=; b=h0x8dbJ2mGxJmpfUNHWdR2K9nWn/mlSmoJa8rA/4qvudJULUn3KC3TYrhOSNr92C+f s/CRChlCKqg1LdHpDEUEfurYXSAAi1HTXYCejr1quc5OYxuwzGQvCX0MGzXRZ95BzVg5 d2uLa12NBCgrlIpjI0du2pcw+Wh/WnG3DJ/3qwP0YhJKYkiWGp10a5AKt4bxgQoO7yJZ i9KkUkYaNOA5A7zK0Y1NOUQ+9o0ej1B6J5B5v4OsdSWgqfibknk/mzZFg76YbE5xjZhV XMSIb29mP8dCXISTaQXTWZ/hT0Q/UruhEvYGVSkHSVxsshqYI5m2XAAEGU7hNoAHgpSI fOOg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=n93r+1hk3C/7yvzA9F2/n1lJlZFVvO8fgbioy7xNIv8=; b=QxadAcn9Sl6wh9JFOrDn5XMG2TF+W4/w7s1UOhEOjq2wk1QRIfI00nhj4SgsSf1AB8 bwA75m1TIi4E9rNW2eQqLzFvUusy0j2MbFcosPCWsoB65XSFBJ/a3Ouh7E1Q48NgoavM vrizaQBqfDrhszFX8ZlWuYMJICYbpRBa9QATiiJk2/7dDqaxNwtpoFX5T5Ugg3qXf1Eo y89pGcgTPpAEqSL2BaHvr6SHUk1ImPcrVXAuz+dKxZxM9C2wPAm+hywfB5kqepf6vRIw WOHS4I9KHkZ3PP/p8JCJ8G+Sa9F+DU6M1pi9oPlgxb1lPlJbZSRceJhXzkaYKKrLdjoX uUOQ== X-Gm-Message-State: ALyK8tKI5REB/xgDihtpLOFFc+vO/BoQUItYkcQTWkQ8WtXD08Tfas4fAsFBE57Wco0Jlg== X-Received: by 10.28.176.129 with SMTP id z123mr16967408wme.99.1467151196811; Tue, 28 Jun 2016 14:59:56 -0700 (PDT) Received: from [10.114.7.71] ([41.33.219.246]) by smtp.gmail.com with ESMTPSA id b200sm914471wmb.9.2016.06.28.14.59.55 (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 28 Jun 2016 14:59:55 -0700 (PDT) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (1.0) From: Eric Voskuil X-Mailer: iPhone Mail (13F69) In-Reply-To: Date: Tue, 28 Jun 2016 23:59:54 +0200 Content-Transfer-Encoding: quoted-printable Message-Id: <7F95A7F5-848C-4EA6-9503-C48F45AC1C34@voskuil.org> References: <87h9cecad5.fsf@rustcorp.com.au> <1E86A00F-0609-4DBC-9543-94AE04CC13C9@voskuil.org> <577234A4.3030808@jonasschnelli.ch> <360EF9B8-A174-41CA-AFDD-2BC2C0B4DECB@voskuil.org> <20160628182202.GA5519@fedora-21-dvm> <20160628201447.GA1148@fedora-21-dvm> <4DCF7DD2-6533-4F79-8CA1-871B67C01BDA@voskuil.org> <20160628203605.GA1328@fedora-21-dvm> To: Gregory Maxwell X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, MIME_QP_LONG_LINE, RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Cc: Bitcoin Protocol Discussion Subject: Re: [bitcoin-dev] BIP 151 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, 28 Jun 2016 22:00:02 -0000 > On Jun 28, 2016, at 11:36 PM, Gregory Maxwell wrote: >=20 > On Tue, Jun 28, 2016 at 9:22 PM, Eric Voskuil via bitcoin-dev > wrote: >> An "out of band key check" is not part of BIP151. >=20 > It has a session ID for this purpose. Passing the session ID out of band is authentication. As this is explicitly n= ot part of BIP151 it cannot be that BIP151 provides the tools to detect a at= tack (the point at issue). >> It requires a secure channel and is authentication. So BIP151 doesn't pro= vide the tools to detect an attack, that requires authentication. A general r= equirement for authentication is the issue I have raised. >=20 > One might wonder how you ever use a Bitcoin address, or even why we might g= uess these emails from "you" aren't actually coming from the NSA. The sarcasm is counterproductive Greg. By the same token I could ask how you= ever use Bitcoin given that the P2P protocol is not encrypted or authentica= ted. It doesn't matter who I am, maybe I am the NSA. I don't argue from a positio= n of authority. Signing my emails while traveling on holiday with only my ph= one gets a little tedious. The blockchain and mempool are a cache of public data. Transmission of a pay= ment address to a payer is not a comparable scenario. The possibility that authentication may become required to participate in th= is trustless network is a legitimate concern, and one that has not been addr= essed. e=