diff options
author | Eric Voskuil <eric@voskuil.org> | 2016-11-17 03:22:03 -0800 |
---|---|---|
committer | bitcoindev <bitcoindev@gnusha.org> | 2016-11-17 11:22:04 +0000 |
commit | 5c973e139bae0a70af60adc8e2d5850cfea4a0d5 (patch) | |
tree | 46d0f315256a116635f89770dc1488b7a2b35ea0 | |
parent | deed15441eecdc47d6266ad60739f7bfc90e1fba (diff) | |
download | pi-bitcoindev-5c973e139bae0a70af60adc8e2d5850cfea4a0d5.tar.gz pi-bitcoindev-5c973e139bae0a70af60adc8e2d5850cfea4a0d5.zip |
Re: [bitcoin-dev] BIP30 and BIP34 interaction (was Re: [BIP Proposal] Buried Deployments)
-rw-r--r-- | 1e/ec1d627a83dda6af1b9b48097dfc2ee2ce2583 | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/1e/ec1d627a83dda6af1b9b48097dfc2ee2ce2583 b/1e/ec1d627a83dda6af1b9b48097dfc2ee2ce2583 new file mode 100644 index 000000000..f87087252 --- /dev/null +++ b/1e/ec1d627a83dda6af1b9b48097dfc2ee2ce2583 @@ -0,0 +1,180 @@ +Return-Path: <eric@voskuil.org> +Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org + [172.17.192.35]) + by mail.linuxfoundation.org (Postfix) with ESMTPS id 887688DC + for <bitcoin-dev@lists.linuxfoundation.org>; + Thu, 17 Nov 2016 11:22:04 +0000 (UTC) +X-Greylist: whitelisted by SQLgrey-1.7.6 +Received: from mail-pg0-f47.google.com (mail-pg0-f47.google.com [74.125.83.47]) + by smtp1.linuxfoundation.org (Postfix) with ESMTPS id E1DF9309 + for <bitcoin-dev@lists.linuxfoundation.org>; + Thu, 17 Nov 2016 11:22:03 +0000 (UTC) +Received: by mail-pg0-f47.google.com with SMTP id 3so90943506pgd.0 + for <bitcoin-dev@lists.linuxfoundation.org>; + Thu, 17 Nov 2016 03:22:03 -0800 (PST) +DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; + d=voskuil-org.20150623.gappssmtp.com; s=20150623; + h=subject:to:references:from:message-id:date:user-agent:mime-version + :in-reply-to; bh=pPofu3vxC/caTcjzFw3dt7ZVgljg5WvjpKxc6HoQWmE=; + b=ZwTyR8w+rX7Zk9IDrTZOV2vmGau6SMinOZW1PKe5M6SVsouJ52xxOeAUiylXLbHWlm + Hq3P377uxpSxjD+zqxyQDcQg7szg3rg4h4TLe1UwfSF6hnrxmgmd85JO12TSHeGJ0y4T + J8DhHFQeHqE0gv/lIeVJ0ZoPhaoJWKBCUx/+uuQoz6t9+l7DCG/LnKftAsNmK+bo/7Zo + CTjJWt/D3DHEUl2SG6CPvXMwi44MTwNwNpfag7sucDhTak0kMoeJS7SncDP6MRgrK5zf + 8lufxmFyOxZONsVIqWMALLXu6eopMy5C6opPyhOmqCbRvR3VFZATdE8p/M90NcOJKT79 + OiyA== +X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; + d=1e100.net; s=20130820; + h=x-gm-message-state:subject:to:references:from:message-id:date + :user-agent:mime-version:in-reply-to; + bh=pPofu3vxC/caTcjzFw3dt7ZVgljg5WvjpKxc6HoQWmE=; + b=WdKHWL2FZrcfKmUIOkk+6vrP/irGCeQ+kbT45+4v07n5lkv6kdVOe9aKDRMyOdqcdp + SRmjQs+KZmlSgWkvBClLsjhbGdyfG/AoEHnIEr1bJaqeNO6tNwhNmlCMy1wmyDhIruww + CV1vNiWGpmtsI6t3Nyv90LM4AEllZSweH3YbDVrnSA6B5eHG/iSyq6jhCrxUxAGmpEqH + TQBbNuqY+B5PpSmho8UrhPV0y4P3vO1YJd1QOKPVx4qq+JYirQKP9eXpUXsjsuTg0bAW + yuuPwHveyb/DmILhgXqLpSJoK3Gaow+PdCb65h9x4iM6rrg2tIvyCMBk2wGMIj834YFF + G14g== +X-Gm-Message-State: ABUngvdJM9Kyysu4Sd2JVQtcWEwxCIE8OmBCx9B7RWsg/c/Xxx2OzHPetJ9rof5n6ayYnQ== +X-Received: by 10.98.90.132 with SMTP id o126mr4021688pfb.41.1479381723164; + Thu, 17 Nov 2016 03:22:03 -0800 (PST) +Received: from ?IPv6:2601:600:9000:d69e:8084:4206:2529:776d? + ([2601:600:9000:d69e:8084:4206:2529:776d]) + by smtp.gmail.com with ESMTPSA id + b64sm6426909pfc.74.2016.11.17.03.22.02 + for <bitcoin-dev@lists.linuxfoundation.org> + (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); + Thu, 17 Nov 2016 03:22:02 -0800 (PST) +To: bitcoin-dev@lists.linuxfoundation.org +References: <CABm2gDr2-MCiaFFjgUFP5Xc0fQfuqJ3=ZkrzjHqmOiwRZ50CBw@mail.gmail.com> + <d58ee114-00fd-23c8-9ca7-9a4b28c26f27@voskuil.org> + <CAE-z3OX5vak25UWcmBSe63OmoOVoGB394WmwyWwUcSxWeDOLhw@mail.gmail.com> + <e0e6679f-aec6-a579-667d-b5b58ea2360b@voskuil.org> + <CAE-z3OXfJa3Lewtrafm25bdfPa=eiarOAXBNbgc3ccTi7Qoe6A@mail.gmail.com> +From: Eric Voskuil <eric@voskuil.org> +X-Enigmail-Draft-Status: N0110 +Message-ID: <5ef23296-5909-a350-ab11-e717f8fffc41@voskuil.org> +Date: Thu, 17 Nov 2016 03:22:03 -0800 +User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 + Thunderbird/45.3.0 +MIME-Version: 1.0 +In-Reply-To: <CAE-z3OXfJa3Lewtrafm25bdfPa=eiarOAXBNbgc3ccTi7Qoe6A@mail.gmail.com> +Content-Type: multipart/signed; micalg=pgp-sha1; + protocol="application/pgp-signature"; + boundary="DtpSSIt28nqorWbD08hVUPGlwLuDDgmtH" +X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DKIM_SIGNED, + DKIM_VALID,RCVD_IN_DNSWL_NONE 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: Thu, 17 Nov 2016 11:22:42 +0000 +Subject: Re: [bitcoin-dev] BIP30 and BIP34 interaction (was Re: [BIP + Proposal] Buried Deployments) +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: Thu, 17 Nov 2016 11:22:04 -0000 + +This is an OpenPGP/MIME signed message (RFC 4880 and 3156) +--DtpSSIt28nqorWbD08hVUPGlwLuDDgmtH +Content-Type: text/plain; charset=utf-8 +Content-Transfer-Encoding: quoted-printable + +On 11/17/2016 02:22 AM, Tier Nolan via bitcoin-dev wrote: +> On Thu, Nov 17, 2016 at 12:43 AM, Eric Voskuil <eric@voskuil.org +> <mailto:eric@voskuil.org>> wrote: +>=20 +> > This means that all future transactions will have different txids= +=2E.. +> rules do guarantee it. +>=20 +> No, it means that the chance is small, there is a difference. +>=20 +> I think we are mostly in agreement then? It is just terminology. + +Sure, if you accept that mostly is not fully - just as unlikely is not +impossible. + +> In terms of discussing the BIP, barring a hash collision, it does make +> duplicate txids impossible. + +That's like saying, as long as we exclude car accidents from +consideration, car accidents are impossible. + +> Given that a hash collision is so unlikely, the qualifier should be +> added to those making claims that require hash collisions rather than +> those who assume that they aren't possible. +>=20 +> You could have said "However nothing precludes different txs from havin= +g +> the same hash, but it requires a hash collision". + +I generally try to avoid speaking in tautologies :) + +> Thinking about it, a re-org to before the enforcement height could allo= +w +> it. The checkpoints protect against that though. +> =20 +> As such this is not something that a node +> can just dismiss.=20 +>=20 +> The security of many parts of the system is based on hash collisions no= +t +> being possible. + +This is not the case. + +Block hash duplicates within the same chain are invalid as a matter of +consensus, which is the opposite of assuming impossibility. + +Tx hash collisions are explicitly allowed in the case that preceding tx +with the same hash is unspent. This is also not a reliance on the +impossibility of hash collision. Core certainly implements this distincti= +on: + +https://github.com/bitcoin/bitcoin/blob/master/src/main.cpp#L2419-L2426 + +Address hashes and script hashes can collide without harming the +security of Bitcoin (although address owner(s) may experience harm). +Rare in this case is sufficient because of this distinction. + +Compact blocks contemplates hash collisions: + +https://github.com/bitcoin/bips/blob/master/bip-0152.mediawiki#Random_col= +lision_probabilty + +Checkpoints aren't part of Bitcoin security, so even the remote +possibility of two different potential blocks, with the same hash, at +the same height in the same chain, does not indicate a problem. + +There is no case where the security of Bitcoin assumes that hashes never +collide. Consensus rules have specific handling for both block hash +collisions and tx hash collisions. + +e + + +--DtpSSIt28nqorWbD08hVUPGlwLuDDgmtH +Content-Type: application/pgp-signature; name="signature.asc" +Content-Description: OpenPGP digital signature +Content-Disposition: attachment; filename="signature.asc" + +-----BEGIN PGP SIGNATURE----- +Version: GnuPG v2.0.22 (GNU/Linux) + +iQEcBAEBAgAGBQJYLZLbAAoJEDzYwH8LXOFOFTQIAIdcDnwiwfv+5jFhwr6ZUU8J +2gSZTlVCO7p7RYwqBrvB3oEm6N7Mxspn751SLzIea22LoPEL2OqJRB2l/rYwGJ1k +lQ2eyInXt8CQICj0Dfa9p6zJnPzIGbauz4z462gc+XGceJv36sShrE3X5ZS61b5F +W2vSC6jNBz3OlRg3KocCyhNaUDxDqWslE7iMdRzFNTCTsxWu3bc0ioblCsjvmmJo +Xeb0+5kitMQK/jh0BvT2Tt1/0B9Ymeq9QeDg8sSaK9Cyw15ZEBmCPLIdYnumB7V3 +Jw8eo92FaXtHaaSwhRYIOn/MqrkIgsy4/+zk52LddXz+2pvsyvLRR+rCKhVCfJA= +=zb3u +-----END PGP SIGNATURE----- + +--DtpSSIt28nqorWbD08hVUPGlwLuDDgmtH-- + |