1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
|
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 3C4C0AB6
for <bitcoin-dev@lists.linuxfoundation.org>;
Thu, 17 Nov 2016 00:10:07 +0000 (UTC)
X-Greylist: whitelisted by SQLgrey-1.7.6
Received: from mail-pf0-f180.google.com (mail-pf0-f180.google.com
[209.85.192.180])
by smtp1.linuxfoundation.org (Postfix) with ESMTPS id CA125254
for <bitcoin-dev@lists.linuxfoundation.org>;
Thu, 17 Nov 2016 00:10:06 +0000 (UTC)
Received: by mail-pf0-f180.google.com with SMTP id d2so45419594pfd.0
for <bitcoin-dev@lists.linuxfoundation.org>;
Wed, 16 Nov 2016 16:10:06 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=voskuil-org.20150623.gappssmtp.com; s=20150623;
h=subject:to:references:cc:from:message-id:date:user-agent
:mime-version:in-reply-to;
bh=e7RaiGfAlLNx0OREIXnZ+U2RVr9P1azcfTD7eHwT6nU=;
b=pKxGfyXAjTIRoa37xZMLP3a7K+W5wvenWkf+Usq2SjoVb4WsQa/IrDrOzLBn/iiWPv
qkd33MzfDkx5zNOY3MuSN9B03bXGzj09hEikXPcf3JH11KdyzVlxCeESIc3eWPTqDPMb
Df1SqfXyFiazJN2QB6yRoU59/BIA8q/PBbivCzOD/KsIfHIOwnB+ibeYrJD3kiPsh7yl
ZPganSU+OYkDkd4iNnDn+i70p5S8l3aZMk9CJDdoSMh6Fzw8azx0IDL9aknFdMmZfytg
GJuwEc6cc0UsdxYO1T7w3F/7anz0aJ6fHaPFloKRFWfMqaXIeo9nro5aG4nTjkJCShL4
Dyvg==
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:cc:from:message-id:date
:user-agent:mime-version:in-reply-to;
bh=e7RaiGfAlLNx0OREIXnZ+U2RVr9P1azcfTD7eHwT6nU=;
b=khIEYraJev8WSjkRWXOl8C9Kov4Mp3gzdHVPbrjMTXvJtJzva2eSVhx+5qGXY8CPIw
xHAUJGwhCry2O/FWeJI1AETbT0CWooPAZ2470wdPpQA2iov7da73uQmtiOUoqtu80vkd
IeOLaeyNbT+fNfK9eCjN7+MurOwg7n745SbNzFFvoIVaX3ESnUbBb/jgohsT1bKzs5Zd
BcMgADbVRDEDehYra3hWwgh9QP8XUTtWf42eobXVNMzP3wtqiRdsNCkxKhM9hOG9NzKC
R0DrOE0n6TB/UZ9h3CoroJuzeF1Uajm9O8w4d3Hii67PJwvlNHw3hVnf+RkdOHXIEor7
NZqg==
X-Gm-Message-State: ABUngvdMC29Is2NBviEGd5VioM1QpKUg2pLysfqGwIPWTqgOI2rWDYsx+SViRuXuDlB6CQ==
X-Received: by 10.98.57.144 with SMTP id u16mr424649pfj.142.1479341406423;
Wed, 16 Nov 2016 16:10:06 -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 d1sm299994pfb.76.2016.11.16.16.10.05
(version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128);
Wed, 16 Nov 2016 16:10:05 -0800 (PST)
To: =?UTF-8?Q?Jorge_Tim=c3=b3n?= <jtimon@jtimon.cc>
References: <CABm2gDr2-MCiaFFjgUFP5Xc0fQfuqJ3=ZkrzjHqmOiwRZ50CBw@mail.gmail.com>
From: Eric Voskuil <eric@voskuil.org>
Message-ID: <d58ee114-00fd-23c8-9ca7-9a4b28c26f27@voskuil.org>
Date: Wed, 16 Nov 2016 16:10:07 -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: <CABm2gDr2-MCiaFFjgUFP5Xc0fQfuqJ3=ZkrzjHqmOiwRZ50CBw@mail.gmail.com>
Content-Type: multipart/signed; micalg=pgp-sha1;
protocol="application/pgp-signature";
boundary="3KPxTi4ERFs1aE3CfI5tgARc65aNkw5iA"
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 00:12:30 +0000
Cc: Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>,
Thomas Kerin <me@thomaskerin.io>
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 00:10:07 -0000
This is an OpenPGP/MIME signed message (RFC 4880 and 3156)
--3KPxTi4ERFs1aE3CfI5tgARc65aNkw5iA
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable
No, BIP30 prevents duplicate tx hashes in the case where the new tx hash
duplicates that of a preceding tx with unspent outputs.
There was one such case that had already become buried in the chain at
the time, so it was exempted from validation. There was another case of
a duplicate hash, but it's predecessor was spent so it complied with the
new rule.
Both of these cases resulted from exact duplicate txs, which BIP34 now
precludes. However nothing precludes different txs from having the same
hash.
e
On 11/16/2016 04:06 PM, Jorge Tim=C3=B3n wrote:
> On Thu, Nov 17, 2016 at 1:00 AM, Eric Voskuil <eric@voskuil.org> wrote:=
>> This is a misinterpretation of BIP30. Duplicate transaction hashes can=
>> and will happen and are perfectly valid in Bitcoin. BIP34 does not
>> prevent this.
>=20
> Sorry for moving the topic, but isn't duplication of tx hashes
> precisely what BIP30 prevents?
> That was my undesrtanding but should read it again.
> Since regular txs take inputs, the collision is extremely unlikely
> (again, this is my understanding, please correct me when wrong), the
> worrying case is coinbase txs (which don't have input to take entropy
> from). By introducing the committed height, collisions on coinbase txs
> are prevented too.
>=20
> If I'm wrong on any of this I'm more than happy to learn why.
>=20
--3KPxTi4ERFs1aE3CfI5tgARc65aNkw5iA
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)
iQEcBAEBAgAGBQJYLPVfAAoJEDzYwH8LXOFODZcH/izM2glNTqbi6k4R6o6SiQvO
PIGrJEtJAXXaJWjVRqL0CwC3CREk7gzYHsYWXH4UM7H6KYi5OReKyaU3q9Fq/VZu
vaFPWI6yr4Fjateeshu5QnjzCe07lNFUlUT7Fpto3N7Js+I4QQCylCyxdxlm6+fO
Qc2J45KcFN991Arn+PsTwEorx+qbjHqVua6SM21yGy3izD/JEVQV7tO7o6H88Eq1
Hei0esr+hFvfcQTGRIk7s2ZZtBRWqGid81gYWqWMexMqOafSILHOJcGetXum1Ytx
rOA3DeKDPeixmu2Ryr5TfUD6kPE2SR4q5/OqnqkuT2D++qUJj1cQjVcUs8HPxow=
=ifYF
-----END PGP SIGNATURE-----
--3KPxTi4ERFs1aE3CfI5tgARc65aNkw5iA--
|
