From: "Jorge Timón" <jtimon@jtimon•cc>
To: Gavin Andresen <gavinandresen@gmail•com>
Cc: Bitcoin Dev <bitcoin-dev@lists•linuxfoundation.org>
Subject: Re: [bitcoin-dev] Time to worry about 80-bit collision attacks or not?
Date: Mon, 11 Jan 2016 21:32:15 +0100 [thread overview]
Message-ID: <CABm2gDrQx-ETyCk1XOCGKwsLeTQU_gPG_Gpjx=bbf2qHpE1u=w@mail.gmail.com> (raw)
In-Reply-To: <CABsx9T0WRXz54LZnyU7Fr=_ZgwF5armj0Z8uwYcFy2x+BWooxg@mail.gmail.com>
On Fri, Jan 8, 2016 at 4:50 PM, Gavin Andresen via bitcoin-dev
<bitcoin-dev@lists•linuxfoundation.org> wrote:
> And to fend off the messag that I bet somebody is composing right now:
>
> Yes, I know about a "security first" mindset. But as I said earlier in the
> thread, there is a tradeoff here between crypto strength and code
> complexity, and "the strength of the crypto is all that matters" is NOT
> security first.
If the crypto code is properly encapsulated, the code complexity costs
of choosing one hashing function over another should be non-existent.
You made the space argument which is valid, but in my opinion code
complexity shouldn't be a valid concern in this discussion.
As a maybe uninteresting anecdote, I proposed the asset IDs in
https://github.com/ElementsProject/elements/tree/alpha-0.10-multi-asset
to do the same ```ripemd160 . sha256``` choice that Mark Friedenbach
had proposed and I had approved for
https://github.com/jtimon/freimarkets/blob/master/doc/freimarkets_specs.org#asset-tags
. More humble than me, he admitted he had made a design mistake much
earlier than me, who (maybe paradoxically) probably had less knowledge
for making crypto choices at the low level. In the end I was convinced
with examples I failed to write down for documentation and can't
remember.
That's not to say I have anything to say in this debate other than
code complexity (which I do feel qualified to talk about) shouldn't be
a concern in this debate. Just want to focus the discussion on what it
should be: security vs space tradeoff.
Since I am admittedly in doubt, I tend to prefer to play safe, but
neither my feelings nor my anecdote are logical arguments and should,
therefore, be ignored for any conclusions in the ```ripemd160 .
sha256``` vs sha256d debate. Just like you non-sequitor "sha256d will
lead to more code complexity", if anything, sha256d should be simpler
than ```ripemd160 . sha256``` (but not simpler enough that it matters
much).
next prev parent reply other threads:[~2016-01-11 20:32 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-07 19:02 Gavin Andresen
2016-01-07 19:13 ` Matt Corallo
2016-01-07 19:19 ` Adam Back
2016-01-07 20:56 ` Dave Scotese
2016-01-07 21:06 ` Gavin Andresen
2016-01-07 22:56 ` Ethan Heilman
2016-01-07 23:39 ` Gavin Andresen
2016-01-08 1:26 ` Matt Corallo
2016-01-08 1:54 ` Gavin Andresen
2016-01-08 17:38 ` Pieter Wuille
2016-01-08 18:41 ` Peter Todd
2016-01-07 20:40 ` Ethan Heilman
2016-01-07 23:52 ` Pieter Wuille
2016-01-08 1:00 ` Gavin Andresen
2016-01-08 1:27 ` Watson Ladd
2016-01-08 3:30 ` Rusty Russell
2016-01-08 3:41 ` Matt Corallo
2016-01-08 12:02 ` Rusty Russell
2016-01-08 12:38 ` Gavin Andresen
2016-01-08 14:34 ` Watson Ladd
2016-01-08 15:26 ` Adam Back
2016-01-08 15:33 ` Anthony Towns
2016-01-08 15:46 ` Gavin Andresen
2016-01-08 15:50 ` Gavin Andresen
2016-01-08 15:59 ` Gavin Andresen
2016-01-11 20:32 ` Jorge Timón [this message]
2016-01-08 16:06 ` Gavin Andresen
2016-01-11 3:57 ` Rusty Russell
2016-01-11 6:57 ` Peter Todd
2016-01-11 23:57 ` Tier Nolan
2016-01-12 0:00 ` Tier Nolan
2016-01-12 12:08 ` Gavin Andresen
2016-01-12 23:22 ` Zooko Wilcox-O'Hearn
2016-01-08 18:52 ` Peter Todd
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