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 E6D9EC70; Fri, 26 Feb 2016 01:34:25 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-oi0-f52.google.com (mail-oi0-f52.google.com [209.85.218.52]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 6F06B20D; Fri, 26 Feb 2016 01:34:25 +0000 (UTC) Received: by mail-oi0-f52.google.com with SMTP id x21so52711213oix.2; Thu, 25 Feb 2016 17:34:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=xzpDFnWxVn+xs77Uvl06d9qhtN9gb0zlYwtYi1YrlmQ=; b=rbTCcVysBLUbChPbUSF4JTWCFwCur4hbjeuqAMoxvseTMWYOTRWf6/Ov6Lvgqr/bGp b0xDJygNFjEvATsR0W/ycl6y+p9j9/BQdcmMQUn2+kxKuhARAGo40V3wha+Jt2cf++VU +LT8UxHG5u8kbl1LAa4KyBaLrezhYd5k/6hN6tztKN1MSYe+TjxBpmxG3a9s3ML6buJ2 OIRdZ0g7GDVQcI98tSgbonAnA3shyFaSrN5QILnYSk+QCuEGiBW2cQmJBdFIYbTBjBUQ uzyGOzXXhV/d0zbtMjYJ9F2Y8ewTFQZ5J7QRQRkNLLorMKxX62MlRUuVElUxCsmlmDh8 P+wQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:content-type; bh=xzpDFnWxVn+xs77Uvl06d9qhtN9gb0zlYwtYi1YrlmQ=; b=LpKkvcLiLLZAP2UqkcAsqTA8tZO57SNcll4b2NXnp2uKSRyLZKe5OGFJDJkshXEtel JxvJtkSpdhxV5qQilCD5jh+tLxF/iJ4j3O+Ot1gBbtlb0L3WnbtRbDxTHCa8aWHHxEW8 xY6eXxQuOftt8k1W2QJdsbUkcrJEvn+uPNik8R8UQxydsGuOqVkt9ejhJEFRb8+fZllH PKi114IzXfhYD26n2ASNg2fSM1NH1RKs10aD6SZMayRNCCdlw8XF5LwGr/s/OZ+p+yJy r2elL5Mq/meX0olFK7cy3Lxldf7LQACcMAAJygKPQ71s0k45wholI0oH77mEisSnwx/1 K8/w== X-Gm-Message-State: AG10YOR17V6demUKUd22nVpngnLfVLIQFEePmNu8sMCu2VnIe221IcRikofGlQeMyZJi9LiYibvqN/TbnLy8OQ== MIME-Version: 1.0 X-Received: by 10.202.172.149 with SMTP id v143mr37346032oie.121.1456450464779; Thu, 25 Feb 2016 17:34:24 -0800 (PST) Received: by 10.157.17.117 with HTTP; Thu, 25 Feb 2016 17:34:24 -0800 (PST) In-Reply-To: <20160226010746.GB10295@lightning.network> References: <20160226010746.GB10295@lightning.network> Date: Thu, 25 Feb 2016 19:34:24 -0600 Message-ID: From: Bryan Bishop To: Joseph Poon , Bitcoin Dev , lightning-dev , Bryan Bishop Content-Type: text/plain; charset=UTF-8 X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org X-Mailman-Approved-At: Fri, 26 Feb 2016 01:35:35 +0000 Subject: Re: [bitcoin-dev] SIGHASH_NOINPUT in Segregated Witness X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Development Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 26 Feb 2016 01:34:26 -0000 On Thu, Feb 25, 2016 at 7:07 PM, Joseph Poon wrote: > This would be achieved using a SIGHASH flag, termed SIGHASH_NOINPUT. It > does not include as part of the signature, the outpoint being spent > (txid and index), nor the amount. It however, would include the spent > outpoint's script as part of the signature. Note that this is just a Well if you are bothering to draft up a BIP about that SIGHASH flag, then perhaps also consider some other SIGHASH flag types as well while you are at it? Various proposed sighash types: http://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-August/010759.html "Build your own nHashType" proposal draft: https://github.com/scmorse/bitcoin-misc/blob/master/sighash_proposal.md jl2012's reply: http://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-August/010779.html petertodd's reply about OP_CODESEPARATOR linked back to this thread regarding "Build your own nHashType": http://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-April/007771.html http://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-April/007802.html http://gnusha.org/bitcoin-wizards/2014-12-09.log ((That particular thread had other replies which can be viewed here: http://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-April/thread.html )) Also, there was a draft implementation of SIGHASH_NOINPUT: https://github.com/Roasbeef/bitcoin/commit/4b3c3f1baf7985208ceb6887261ee150ab6e3328 https://github.com/Roasbeef/btcd/commit/67830e506fa135d5239177340918cea39909e6a4 FWIW there was some concern about replay using SIGHAHS_NOINPUT or something: http://gnusha.org/bitcoin-wizards/2015-04-07.log - Bryan http://heybryan.org/ 1 512 203 0507