Re: [Bitcoin-development] Time

[Mike Hearn <mike@plan99.net>]

[-- Attachment #1: Type: text/plain, Size: 2790 bytes --]

Given that the speed at which the block chain advances is kind of
unpredictable, I'd think it might be better to just record the time to disk
when a PIN attempt is made and if you observe time going backwards, refuse
to allow more attempts until it's advanced past the previous attempt.


On Fri, Jul 25, 2014 at 7:56 AM, Aaron Voisine <voisine@gmail.com> wrote:

> It's based on the block height, not the block's timestamp. If you have
> access to the device and the phone itself is not pin locked, then you
> can jailbreak it and get access to the wallet seed that way. A pin
> locked device however is reasonably secure as the filesystem is
> hardware aes encrypted to a combination of pin+uuid. This was just an
> easy way to prevent multiple pin guesses by changing system time in
> settings, so that isn't the weakest part of the security model.
>
> Aaron Voisine
> breadwallet.com
>
>
> On Thu, Jul 24, 2014 at 8:21 PM, William Yager <will.yager@gmail.com>
> wrote:
> > On Thu, Jul 24, 2014 at 10:39 PM, Gregory Maxwell <gmaxwell@gmail.com>
> > wrote:
> >>
> >>
> >> Is breadwallet tamper resistant & zero on tamper hardware? otherwise
> >> this sounds like security theater.... I attach a debugger to the
> >> process (or modify the program) and ignore the block sourced time.
> >>
> >
> > It's an iOS application. I would imagine it is substantially more
> difficult
> > to attach to a process (which, at the very least, requires root, and
> perhaps
> > other things on iOS) than to convince the device to change its system
> time.
> >
> > That said, the security benefits might not be too substantial.
> >
> >
> ------------------------------------------------------------------------------
> > Want fast and easy access to all the code in your enterprise? Index and
> > search up to 200,000 lines of code with a free copy of Black Duck
> > Code Sight - the same software that powers the world's largest code
> > search on Ohloh, the Black Duck Open Hub! Try it now.
> > http://p.sf.net/sfu/bds
> > _______________________________________________
> > Bitcoin-development mailing list
> > Bitcoin-development@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/bitcoin-development
> >
>
>
> ------------------------------------------------------------------------------
> Want fast and easy access to all the code in your enterprise? Index and
> search up to 200,000 lines of code with a free copy of Black Duck
> Code Sight - the same software that powers the world's largest code
> search on Ohloh, the Black Duck Open Hub! Try it now.
> http://p.sf.net/sfu/bds
> _______________________________________________
> Bitcoin-development mailing list
> Bitcoin-development@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
>

[-- Attachment #2: Type: text/html, Size: 4085 bytes --]