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Date: Sat, 8 Mar 2014 15:55:18 +0900
Message-ID: <CA+su7OUMgeWgkMFAmmMEpW3eN=cvU47MKt51idDrmCWEiCb+VQ@mail.gmail.com>
From: Edmund Edgar <ed@realitykeys.com>
To: bitcoin-development@lists.sourceforge.net
Content-Type: multipart/alternative; boundary=047d7b10cae57005af04f412dae3
Subject: Re: [Bitcoin-development] Is this a safe thing to be doing with ECC
 addition? (Oracle protocol)
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On 4 March 2014 14:07, Odinn Cyberguerrilla <odinn.cyberguerrilla@riseup.net
> wrote:

> Nothing is safe.
>

This is true. To rephrase, imagine I gave you an ECC public key <ed_pub>,
you gave me back a public key <odinn_pub> of your own devising, then I paid
some money to the address resulting from add_pubkeys(<ed_pub>,<odinn_pub>)
[1]. Can anyone either:

a) Think of a way that Odinn could make an <odinn_pub> such that they could
spend the resulting money without having <ed_priv>.
b) Opine, somewhat knowledgeably, that this probably wouldn't be an easy
thing to do, and they wouldn't be alarmed to see people running software
that did this kind of thing.

[1]
https://github.com/vbuterin/pybitcointools/blob/master/pybitcointools/main.py#L173

-- 
Edmund Edgar
Founder, Social Minds Inc (KK)
Twitter: @edmundedgar
Linked In: edmundedgar
Skype: edmundedgar
http://www.socialminds.jp

Reality Keys
@realitykeys
ed@realitykeys.com
https://www.realitykeys.com

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<div dir=3D"ltr"><div class=3D"gmail_extra"><div class=3D"gmail_quote">On 4=
 March 2014 14:07, Odinn Cyberguerrilla <span dir=3D"ltr">&lt;<a href=3D"ma=
ilto:odinn.cyberguerrilla@riseup.net" target=3D"_blank">odinn.cyberguerrill=
a@riseup.net</a>&gt;</span> wrote:<br>
<blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-=
left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;p=
adding-left:1ex">Nothing is safe.<br></blockquote><div><br></div><div>This =
is true. To rephrase, imagine I gave you an ECC public key &lt;ed_pub&gt;, =
you gave me back a public key &lt;odinn_pub&gt; of your own devising, then =
I paid some money to the address resulting from add_pubkeys(&lt;ed_pub&gt;,=
&lt;odinn_pub&gt;) [1]. Can anyone either:</div>
<div><br></div><div>a) Think of a way that Odinn could make an &lt;odinn_pu=
b&gt; such that they could spend the resulting money without having &lt;ed_=
priv&gt;.</div><div>b) Opine, somewhat knowledgeably, that this probably wo=
uldn&#39;t be an easy thing to do, and they wouldn&#39;t be alarmed to see =
people running software that did this kind of thing.</div>
<div><br></div><div>[1]=C2=A0<a href=3D"https://github.com/vbuterin/pybitco=
intools/blob/master/pybitcointools/main.py#L173" target=3D"_blank">https://=
github.com/vbuterin/pybitcointools/blob/master/pybitcointools/main.py#L173<=
/a><br>
<br></div></div><div dir=3D"ltr"><div>--=C2=A0</div><div>Edmund Edgar</div>=
<div>Founder, Social Minds Inc (KK)</div><div>Twitter: @edmundedgar</div><d=
iv>Linked In: edmundedgar</div><div>Skype: edmundedgar</div><div><a href=3D=
"http://www.socialminds.jp" target=3D"_blank">http://www.socialminds.jp</a>=
</div>
<div><br></div><div>Reality Keys</div><div>@realitykeys</div><div><a href=
=3D"mailto:ed@realitykeys.com" target=3D"_blank">ed@realitykeys.com</a></di=
v><div><a href=3D"https://www.realitykeys.com" target=3D"_blank">https://ww=
w.realitykeys.com</a></div>
</div>
</div></div>

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