From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id 5F369C016F for ; Sat, 2 May 2020 21:16:04 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id 471EA8879D for ; Sat, 2 May 2020 21:16:04 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 5-0argF7bXhE for ; Sat, 2 May 2020 21:16:03 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from mail-io1-f51.google.com (mail-io1-f51.google.com [209.85.166.51]) by hemlock.osuosl.org (Postfix) with ESMTPS id 8ACFD88780 for ; Sat, 2 May 2020 21:16:03 +0000 (UTC) Received: by mail-io1-f51.google.com with SMTP id j8so4081988iog.13 for ; Sat, 02 May 2020 14:16:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=blockstream-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=yS6992f3v+N1nAspMU9G4frmEvI6aGmlII46UER2MgI=; b=gmuWQCcy0/nOv3jGogPbVaPFhuH4uz8e+KtSOXRbUaVVrTzNcgwXR7Mmh8g6UMEZsv c8th/emGwiGLLkllfE6geSuHXld2N1xhlArDFrgxKNxLDfmkFGVtWWlvJEL2+yTiTcHt aKKD8XF9TysatPo9yHlOuTV3a/PIUBDxf2h1+ML8eVvJNDcCnpf5tEPIgwG//Pqm/OdQ 9T2rNE2PoIYvwwDnin5UkTxm/l6FGq+6ddDwrSvCrXVWeCkec+At/agaALVd1oyzb7dO qRjfr1r7AYHyDeaJYbpYW0h7yeEaERiFKv+4wRrYonkm0OtW4APZ35mjbrNiKWTQlxsf AhFg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=yS6992f3v+N1nAspMU9G4frmEvI6aGmlII46UER2MgI=; b=P/GDJapkWzmnZGDSSCtRXwQDZ2fyLl/KbpF7vBrjq6CwYffsfqfErjF8GGGX59kvuH c5FVbPz2VrG5XllGyrQeT8g4PGI98wCEVX6NQV73PoW7GJq/SLV4viLQ2qH9dLoqa5b6 a38AOonUm3H5KaZvYJ4jriBlS7rxsADetRp4PLkL5S57DE2WDtPPaiiYGnpA3XuxAL4A dlRitL6UvULowvn994+u+PalErHr8zHfAMgB45uGdlO73ICdVi+uvShNy1KWpLOVR909 GIhdseZD49YYzHIHa2Wx5OcYC1Xz4VmGiPSv1dBv6166L/TKO6AygE1zutl98YP6T1wH GcZA== X-Gm-Message-State: AGi0PuZf5QssYKgLPWZr33/vlE/NN3A7zAuOnhJEysVzuBTKi57R02ko PpPLVh0DSreRAy1Uv0B+K3/bpTq1MdZEIY2Xgv0NuQ== X-Google-Smtp-Source: APiQypJRJh7xoKSpuaTZkLCH4w9we6HDUymELiwfaFGuMuJIMSfle2NOm9nNCy31nE+caaQN+eYHwdzWnX/MuBPWrbQ= X-Received: by 2002:a6b:e413:: with SMTP id u19mr9358631iog.206.1588454162734; Sat, 02 May 2020 14:16:02 -0700 (PDT) MIME-Version: 1.0 References: <20200502142602.rj7q2m32ew6trh6u@erisian.com.au> In-Reply-To: <20200502142602.rj7q2m32ew6trh6u@erisian.com.au> From: "Russell O'Connor" Date: Sat, 2 May 2020 17:15:51 -0400 Message-ID: To: Anthony Towns Content-Type: multipart/alternative; boundary="0000000000001cb04505a4b0ce8b" Cc: jonasd.nick@gmail.com, Bitcoin Protocol Discussion , Pieter Wuille Subject: Re: [bitcoin-dev] BIP-341: Committing to all scriptPubKeys in the signature message X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 02 May 2020 21:16:04 -0000 --0000000000001cb04505a4b0ce8b Content-Type: text/plain; charset="UTF-8" On Sat, May 2, 2020 at 10:26 AM Anthony Towns wrote: > > except that we'd arguably still be missing: > > is this a coinbase output? (Coin.fCoinBase) > what was the height of the coin? (Coin.nHeight) > > Maybe committing to the coinbase flag would have some use, but committing > to the height would make it hard to chain unconfirmed spends, so at > least that part doesn't seem worth adding. > To add to this point, the height of the coin is something that is *not* currently covered by any signature mode and including it would constitute a change of an entirely different caliber; a change that I would strongly caution against for your above reason and more. The coinbase output flag is currently covered by the signature as the outpoint hash has the required information (its prevout index of 0xFFFFFFFF is only legal in a coinbase transaction). While I'm not particularly enthusiastic about making it easier to distinguish coinbase outputs from other outputs, and I worry a little about alternative designs for implementing the Bitcoin protocol where this information is not so readily available, I suppose I won't really oppose adding it. However, I don't think anyone is seriously proposing it. - --0000000000001cb04505a4b0ce8b Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
On Sat, May 2, 2020 at 10:26 AM Anthony Towns <aj@erisian.com.au> wrote:

except that we'd arguably still be missing:

=C2=A0 =C2=A0 is this a coinbase output? (Coin.fCoinBase)
=C2=A0 =C2=A0 what was the height of the coin? (Coin.nHeight)

Maybe committing to the coinbase flag would have some use, but committing to the height would make it hard to chain unconfirmed spends, so at
least that part doesn't seem worth adding.

To add to this point, the height of the coin is something that is *= not* currently covered by any signature mode and including it would constit= ute a change of an entirely different=C2=A0 caliber; a change that I would = strongly caution against for your above reason and more.

The coinbase output flag is currently covered by the signature as th= e outpoint hash has the required information (its prevout index of 0xFFFFFF= FF is only legal in a coinbase transaction).=C2=A0 While I'm not partic= ularly enthusiastic about making it easier to distinguish coinbase outputs = from other outputs, and I worry a little about alternative designs for impl= ementing the Bitcoin protocol where this information is not so readily avai= lable, I suppose I won't really oppose adding it.=C2=A0 However, I don&= #39;t think anyone is seriously proposing it.
  • --0000000000001cb04505a4b0ce8b--