Return-Path: <dp@simplexum.com> Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 494DAAB9 for <bitcoin-dev@lists.linuxfoundation.org>; Sat, 29 Jun 2019 04:45:03 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from mail.ruggedbytes.com (mail.ruggedbytes.com [88.99.30.248]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id CE9C72C6 for <bitcoin-dev@lists.linuxfoundation.org>; Sat, 29 Jun 2019 04:45:02 +0000 (UTC) Received: from mail.ruggedbytes.com (localhost [127.0.0.1]) by mail.ruggedbytes.com (Postfix) with ESMTPS id 67A3C2600550; Sat, 29 Jun 2019 04:45:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=simplexum.com; s=mail; t=1561783501; bh=Lo2viYrwOv/zo5zNwO5raG6B8wX5wVgM9KIo6+z7124=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=gDthegG6JlyrRUIlc3pkz89t02rBr9ZTWiLJiyehCw2W4cUa8sVqWDA61nXX410sI ckwB1neI3yqomIc4BjUWFG/iN9fdEBy0fQFDdhiQk+T1xfbhZ06fohfQILhuBwHd1e xKLhhYrSrzO0+7UuCk1Xp9B7O1M8jnZrJJOllD4Y= Date: Sat, 29 Jun 2019 09:46:23 +0500 From: Dmitry Petukhov <dp@simplexum.com> To: Jonathan Underwood <junderwood@bitcoinbank.co.jp> Message-ID: <20190629094623.0324d35c@simplexum.com> In-Reply-To: <CAMpN3m+Oa6oPzAmhoioOkuf8__NSPPNoSEMHJwo9PhjXosMwhg@mail.gmail.com> References: <CAMpN3mLvY+kuUGqzMW6SAMZ=h46_g=XLhDPhSY=X6xhLxvi15Q@mail.gmail.com> <20190627095031.4d5817b8@simplexum.com> <CAMpN3mKPkCPtYkN-JVku1r217-aBK=Rh3UEhvRPS_Y6DixJ9Dw@mail.gmail.com> <20190627122916.3b6c2c32@simplexum.com> <CAMpN3mL8tyP-6-nwn6dorcq7-dad6wYz8_pXinqHhgzUnrr_tg@mail.gmail.com> <20190627181429.15dda570@simplexum.com> <20190627202932.1cb4d727@simplexum.com> <20190629024816.2193363e@simplexum.com> <CAMpN3m+Oa6oPzAmhoioOkuf8__NSPPNoSEMHJwo9PhjXosMwhg@mail.gmail.com> Organization: simplexum.com MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU 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: Sat, 29 Jun 2019 06:20:23 +0000 Cc: Bitcoin development mailing list <bitcoin-dev@lists.linuxfoundation.org> Subject: Re: [bitcoin-dev] BIP174 extension proposal (Global Type: PSBT_GLOBAL_XPUB_SIGNATURE) X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Protocol Discussion <bitcoin-dev.lists.linuxfoundation.org> List-Unsubscribe: <https://lists.linuxfoundation.org/mailman/options/bitcoin-dev>, <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=unsubscribe> List-Archive: <http://lists.linuxfoundation.org/pipermail/bitcoin-dev/> List-Post: <mailto:bitcoin-dev@lists.linuxfoundation.org> List-Help: <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=help> List-Subscribe: <https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev>, <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=subscribe> X-List-Received-Date: Sat, 29 Jun 2019 04:45:03 -0000 =D0=92 Sat, 29 Jun 2019 09:19:41 +0900 Jonathan Underwood <junderwood@bitcoinbank.co.jp> wrote: > > Other note: you have 'unused' value of 1 for `m` in your scheme, why > > not require m=3D1 for single-sig case, and use 0 as indicator that > > there are a serlal number following it? > > =20 >=20 > 0x00 is single sig, aka, OP_CHECKSIG >=20 > 0x01 is multisig, aka, 1-of-3, 1-of-2 OP_CHECKMULTISIG This informatin is available in per-output redeem/witness script, signer will be able to distinguish between multisig/single-sig by looking at this script. I think it only need to know the total number of keys participating in the signing, and check that this number matches the particulars of redeem/witness script.