MIME-Version: 1.0
References: <CAFUsdzpsoia+1XZs2qzWbanYoOT1g_+43=iGutyKYrCjFCCM5w@mail.gmail.com>
In-Reply-To: <CAFUsdzpsoia+1XZs2qzWbanYoOT1g_+43=iGutyKYrCjFCCM5w@mail.gmail.com>
From: James MacWhyte <macwhyte@gmail.com>
Date: Tue, 5 Mar 2019 17:05:54 -0800
Message-ID: <CAH+Axy7YXDC4M0o9WHwaR2k46nWYBtM9VetXyBMx=B9-fxupug@mail.gmail.com>
To: Trey Del Bonis <j.delbonis.3@gmail.com>, 
	Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
Content-Type: multipart/alternative; boundary="000000000000fec2db0583629844"
Subject: Re: [bitcoin-dev] Fortune Cookies to Bitcoin Seed
Precedence: list

--000000000000fec2db0583629844
Content-Type: text/plain; charset="UTF-8"

On Tue, Mar 5, 2019 at 4:39 PM Trey Del Bonis via bitcoin-dev <
bitcoin-dev@lists.linuxfoundation.org> wrote:

> Keeping 20 around is a little excessive but it gives 390700800 possible
> wallets. So security can be trivially parameterized based on how secure you
> want your wallet to be if someone finds your stash.
>

Mid-level hardware can check 50k addresses per second, which means it would
only take around 2 hours to check all possibilities. So please don't think
this presents any kind of challenge to someone who finds your 20 pieces of
paper and assumes you would only keep them if they are hiding your wallet ;)

Entropy-wise, simply using a strong RNG would provide a better result than
relying on the printing company. Maybe they only print 35 different
combinations and assume people don't eat Chinese food enough to notice?

If it's poor entropy and doesn't really provide any protection against
being brute forced if found, I'm not sure why you would want to go
this route :)

James

--000000000000fec2db0583629844
Content-Type: text/html; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

<div dir=3D"ltr"><div dir=3D"ltr"><div><div dir=3D"ltr" class=3D"gmail_sign=
ature" data-smartmail=3D"gmail_signature"><div dir=3D"ltr"><div>On Tue, Mar=
 5, 2019 at 4:39 PM Trey Del Bonis via bitcoin-dev &lt;<a href=3D"mailto:bi=
tcoin-dev@lists.linuxfoundation.org">bitcoin-dev@lists.linuxfoundation.org<=
/a>&gt; wrote:</div></div></div></div></div><div class=3D"gmail_quote"><blo=
ckquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left=
:1px solid rgb(204,204,204);padding-left:1ex">Keeping 20 around is a little=
 excessive but it gives 390700800 possible wallets. So security can be triv=
ially parameterized based on how secure you want your wallet to be if someo=
ne finds your stash.<br></blockquote><div>=C2=A0</div><div>Mid-level hardwa=
re can check 50k addresses per second, which means it would only take aroun=
d 2 hours to check all possibilities. So please don&#39;t think this presen=
ts any kind of challenge to someone who finds your 20 pieces of paper and a=
ssumes you would only keep them if they are hiding your wallet ;)</div><div=
><br></div><div>Entropy-wise, simply using a strong RNG would provide a bet=
ter result than relying on the printing company. Maybe they only print 35 d=
ifferent combinations and assume people don&#39;t eat Chinese food enough t=
o notice?<br><br>If it&#39;s poor entropy and doesn&#39;t really provide an=
y protection against being brute forced if found, I&#39;m not sure why you =
would want to go this=C2=A0route :)</div><div><br></div><div>James</div></d=
iv></div>

--000000000000fec2db0583629844--