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 EBA6A1719; Tue, 1 Oct 2019 14:45:56 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from azure.erisian.com.au (cerulean.erisian.com.au [139.162.42.226]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id B248B8B0; Tue, 1 Oct 2019 14:45:55 +0000 (UTC) Received: from aj@azure.erisian.com.au (helo=sapphire.erisian.com.au) by azure.erisian.com.au with esmtpsa (Exim 4.89 #1 (Debian)) id 1iFJPU-0006eW-8K; Wed, 02 Oct 2019 00:45:53 +1000 Received: by sapphire.erisian.com.au (sSMTP sendmail emulation); Wed, 02 Oct 2019 00:45:48 +1000 Date: Wed, 2 Oct 2019 00:45:48 +1000 From: Anthony Towns To: ZmnSCPxj , Bitcoin Protocol Discussion Message-ID: <20191001144548.hrne6mlhmof7tpkr@erisian.com.au> References: <87wodp7w9f.fsf@gmail.com> <-5H29F71ID9UFqUGMaegQxPjKZSrF1mvdgfaaYtt_lwI7l1OTmN_8OgcooyoMt2_XuyZ5aDljL6gEup9C7skF8iuP_NbMW_81h0tJIGbJno=@protonmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) X-Spam-Score: -1.9 X-Spam-Score-int: -18 X-Spam-Bar: - X-Spam-Status: No, score=-1.5 required=5.0 tests=BAYES_00, DOS_RCVD_IP_TWICE_B, KHOP_HELO_FCRDNS,UNPARSEABLE_RELAY autolearn=no version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Cc: "lightning-dev@lists.linuxfoundation.org" Subject: Re: [bitcoin-dev] Continuing the discussion about noinput / anyprevout 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, 01 Oct 2019 14:45:57 -0000 On Mon, Sep 30, 2019 at 11:28:43PM +0000, ZmnSCPxj via bitcoin-dev wrote: > Suppose rather than `SIGHASH_NOINPUT`, we created a new opcode, `OP_CHECKSIG_WITHOUT_INPUT`. I don't think there's any meaningful difference between making a new opcode and making a new tapscript public key type; the difference is just one of encoding: 3301AC [CHECKSIG of public key type 0x01] 32B3 [CHECKSIG_WITHOUT_INPUT (replacing NOP4) of key] > This new opcode ignores any `SIGHASH` flags, if present, on a signature, (How sighash flags are treated can be redefined by new public key types; if that's not obvious already) Cheers, aj