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
139
140
141
142
143
144
|
Return-Path: <jimmyjack@gmail.com>
Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org
[172.17.192.35])
by mail.linuxfoundation.org (Postfix) with ESMTPS id E8259BE1
for <bitcoin-dev@lists.linuxfoundation.org>;
Wed, 15 Jul 2015 15:49:19 +0000 (UTC)
X-Greylist: whitelisted by SQLgrey-1.7.6
Received: from mail-wi0-f180.google.com (mail-wi0-f180.google.com
[209.85.212.180])
by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 364791EF
for <bitcoin-dev@lists.linuxfoundation.org>;
Wed, 15 Jul 2015 15:49:18 +0000 (UTC)
Received: by wiga1 with SMTP id a1so3789225wig.0
for <bitcoin-dev@lists.linuxfoundation.org>;
Wed, 15 Jul 2015 08:49:17 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113;
h=content-type:mime-version:subject:from:in-reply-to:date:cc
:content-transfer-encoding:message-id:references:to;
bh=lEXxEVF1j/CWp4TP/rNuQrbIqIplLYogT3gPIcIu+Vg=;
b=bZ35a0ZtXFNsZL/VRQ23sW3EeSQnontCWOW80fSv3OR0lTxtzcMntLumamGjOOPOBn
qBdtr1gAD4pxO3l9NBrKge0hyudny4E7/QAHtIRk2h76zJ2PMJ+rrw7k3hCm2J2rR+1U
mNUQiZ2/e8Q2nYDME+ahh5d9MIAg5EK7jkr4iELyNCrrX6CSVaVTQVntjxSlTWN8Dr7P
U96dfhxaabq/wrXKvPna1R2xotgoGyukDMbtWesYnPNrfnOysm5Bmqf14qYbdlVu5gPY
c3ULJw561jqX5brfNtxRbpv3+jiXBvMiOAZByYhThRlMnDhwFUF+gF8Nrk5s6Wd/JS9o
VdOw==
X-Received: by 10.180.79.133 with SMTP id j5mr1547036wix.38.1436975356983;
Wed, 15 Jul 2015 08:49:16 -0700 (PDT)
Received: from [10.0.0.210] ([194.46.128.92]) by smtp.gmail.com with ESMTPSA id
jz4sm8523376wjb.16.2015.07.15.08.49.14
(version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128);
Wed, 15 Jul 2015 08:49:16 -0700 (PDT)
Content-Type: text/plain; charset=utf-8
Mime-Version: 1.0 (Mac OS X Mail 9.0 \(3067\))
From: Me <jimmyjack@gmail.com>
In-Reply-To: <20150715151825.GB20029@savin.petertodd.org>
Date: Wed, 15 Jul 2015 08:49:13 -0700
Content-Transfer-Encoding: quoted-printable
Message-Id: <CDB5FC27-F3F0-44F7-BBC6-670ACAE740D2@gmail.com>
References: <24662b038abc45da7f3990e12a649b8a@airmail.cc>
<55A66FA9.4010506@thinlink.com>
<20150715151825.GB20029@savin.petertodd.org>
To: Peter Todd <pete@petertodd.org>
X-Mailer: Apple Mail (2.3067)
X-Spam-Status: No, score=-2.7 required=5.0 tests=BAYES_00,DKIM_SIGNED,
DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM,
RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.1
X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on
smtp1.linux-foundation.org
Cc: bitcoin-dev@lists.linuxfoundation.org
Subject: Re: [bitcoin-dev] Significant losses by double-spending unconfirmed
transactions
X-BeenThere: bitcoin-dev@lists.linuxfoundation.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: Bitcoin Development 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: Wed, 15 Jul 2015 15:49:20 -0000
Thank you Simon for sharing your tests, if possible can you share TX =
hashes please. I would recommend to send them money post-mortem. What =
you did is really valuable information, however it can be classified as =
fraud. I really don=E2=80=99t want open this topic here, just suggesting =
to keep your record clean :-)=20
> the double-spent txs
> had near 100% propagation on blockchain.info (who has unfortunately
> purged the relevant data already)
Can you please share the TX Hash
> Blockcypher's "confidence factor" model(1)
> under the hood - yet another one of those sybil attacking network
> monitoring things
Peter, I noticed on your twitter you have a lot of bad things to say =
about Blockcypher and their business model (which I might not full =
agree, but totally respect), can you share any evidence they perform any =
form of Sybil attack on the network, please.=20
> On Jul 15, 2015, at 8:18 AM, Peter Todd via bitcoin-dev =
<bitcoin-dev@lists.linuxfoundation.org> wrote:
>=20
> On Wed, Jul 15, 2015 at 07:35:21AM -0700, Tom Harding via bitcoin-dev =
wrote:
>>=20
>> You perform a valuable service with your demonstration, but you
>> neglected to include the txid's to show that you actually did it.
>=20
>> Your advice is must-follow for anyone relying on an unconfirmed tx: =
it
>> must pay a good fee and be highly relayable/minable.
>=20
> Actually, I was looking at what I believe was (part of?) this attack
> yesterday in the logs on my full-RBF nodes and the txs involved *did*
> have good fees and were highly relayable/minable - the double-spent =
txs
> had near 100% propagation on blockchain.info (who has unfortunately
> purged the relevant data already)
>=20
> Shapeshift.io depends on Blockcypher's "confidence factor" model(1)
> under the hood - yet another one of those sybil attacking network
> monitoring things - to estimate tx confirmation probability by looking
> at the % of nodes a tx has propagated too. But miners frequently use
> customized Bitcoin Core codebases that don't follow normal policies, =
so
> those measurements don't actually tell you what you need to know.
>=20
> hapeshift confirmed(2) the attack - confirming that they disabled
> unconfirmed tx acceptance - said they're going to "improve" their
> system... It'll be interesting to see what that actually entails.
>=20
> 1) =
https://medium.com/blockcypher-blog/from-zero-to-hero-bitcoin-transactions=
-in-8-seconds-7c9edcb3b734
> 2) =
https://www.reddit.com/r/Bitcoin/comments/3ddkhy/bitcoindev_significant_lo=
sses_by_doublespending/ct468p7
>=20
> --=20
> 'peter'[:-1]@petertodd.org
> 000000000000000010bf087ed645cba129e2523930d5cde636ddbae9e03aef9c
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
|
