From: Timo Hanke <timo.hanke@web•de>
To: Luke Dashjr <luke@dashjr•org>,
Bitcoin Protocol Discussion
<bitcoin-dev@lists•linuxfoundation.org>
Subject: Re: [bitcoin-dev] Making AsicBoost irrelevant
Date: Wed, 11 May 2016 11:28:42 -0700 [thread overview]
Message-ID: <CAH6h1LsRgZEar8JDR2m-hsTc-DE+=A6BzOq_X2CHSya=bxFRQQ@mail.gmail.com> (raw)
In-Reply-To: <CAH6h1LuVSSxZtOFNGP-Etx-UQGnWMxp1FL0E137yo7D+Wtcs7A@mail.gmail.com>
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Sorry, you must have meant all 12 bytes. That makes finding a collision
substantially harder. However, you may have to restrict yourself to 10
bytes because you don't know if any hardware does timestamp rolling
on-chip. Also you create an incentive to mess around with the version bits
instead, so you would have to fix that as well. So it basically means a new
mining header with the real blockheader as a child header.
On Wed, May 11, 2016 at 9:24 AM, Timo Hanke <timo.hanke@web•de> wrote:
> Luke, do you mean to replace the first 4 bytes of the second chunk (bytes
> 64..67 in 0-based counting) by the XOR of those 4 bytes with the first 4
> bytes of the midstate? (I assume you don't care about 12 bytes but rather
> those 4 bytes.)
>
> This does not work. All it does is adding another computational step
> before you can check for a collision in those 4 bytes. It makes finding a
> collision only marginally harder.
>
> On Wed, May 11, 2016 at 7:28 AM, Luke Dashjr via bitcoin-dev <
> bitcoin-dev@lists•linuxfoundation.org> wrote:
>
>> On Wednesday, May 11, 2016 12:20:55 PM Sergio Demian Lerner via
>> bitcoin-dev
>> wrote:
>> > On Tue, May 10, 2016 at 6:43 PM, Sergio Demian Lerner <
>> > sergio.d.lerner@gmail•com> wrote:
>> > > You can find it here:
>> > >
>> https://bitslog.wordpress.com/2014/03/18/the-re-design-of-the-bitcoin-blo
>> > > ck-header/
>> > >
>> > > Basically, the idea is to put in the first 64 bytes a 4 byte hash of
>> the
>> > > second 64-byte chunk. That design also allows increased nonce space in
>> > > the first 64 bytes.
>> >
>> > My mistake here. I didn't recalled correctly my own idea. The idea is to
>> > include in the second 64-byte chunk a 4-byte hash of the first chunk,
>> not
>> > the opposite.
>>
>> What if we XOR bytes 64..76 with the first 12 bytes of the SHA2 midstate?
>> Would that work?
>>
>> Luke
>> _______________________________________________
>> bitcoin-dev mailing list
>> bitcoin-dev@lists•linuxfoundation.org
>> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>>
>
>
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next prev parent reply other threads:[~2016-05-11 18:28 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-05-10 18:57 Peter Todd
2016-05-10 20:27 ` Tier Nolan
2016-05-10 21:35 ` Matt Corallo
2016-05-10 21:43 ` Sergio Demian Lerner
2016-05-10 22:59 ` Matt Corallo
2016-05-11 12:20 ` Sergio Demian Lerner
2016-05-11 13:08 ` Marek Palatinus
2016-05-11 21:01 ` Matt Corallo
2016-05-11 22:16 ` Simon Liu
2016-05-11 22:50 ` Peter Todd
2016-05-11 14:28 ` Luke Dashjr
2016-05-11 16:24 ` Timo Hanke
2016-05-11 18:28 ` Timo Hanke [this message]
2016-05-11 22:49 ` Timo Hanke
2016-05-12 2:27 ` Tom Harding
2016-05-12 2:31 ` Allen Piscitello
2016-05-12 2:33 ` Peter Todd
2016-05-12 4:01 ` Tom Harding
2016-05-10 21:49 ` Marco Pontello
2016-05-10 22:17 ` Sergio Demian Lerner
2016-05-10 22:27 ` Chris Riley
2016-05-11 3:14 ` Timo Hanke
2016-05-11 9:21 ` Jannes Faber
2016-05-11 10:36 ` Henning Kopp
2016-05-11 10:47 ` Jannes Faber
2016-05-11 22:42 ` Timo Hanke
2016-05-11 22:58 ` Gregory Maxwell
2016-05-12 7:29 ` Tom
2016-05-12 11:05 ` Jorge Timón
2016-05-11 14:07 ` Jorge Timón
2016-05-11 14:18 ` Sergio Demian Lerner
2016-05-11 14:30 ` Jannes Faber
2016-05-11 20:50 ` Matt Corallo
2016-05-11 22:00 ` James Hilliard
2016-05-11 23:01 ` Peter Todd
2016-05-12 0:02 ` Gregory Maxwell
2016-05-12 1:23 ` Russell O'Connor
2016-05-12 1:58 ` Peter Todd
2016-05-12 1:58 ` Matt Corallo
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