[Bitcoin-development] Bug in key.cpp

[Bitcoin-development] Bug in key.cpp

[Srintuar]

[-- Attachment #1: Type: text/plain, Size: 199 bytes --]

I think i see a bug:

line 273 of key.cpp

        if (rec<0 || rec>=3)
            return false;

Afaict, 3 is a perfectly valid value, meaning 25% of sig-> key recoveries
would fail erroneously...

[-- Attachment #2: Type: text/html, Size: 316 bytes --]

Re: [Bitcoin-development] Bug in key.cpp

[odinn.cyberguerrilla]

You are right there is a bug in there.

But the value is not 25% I think.  Tinker some more. :-)

> I think i see a bug:
>
> line 273 of key.cpp
>
>         if (rec<0 || rec>=3)
>             return false;
>
> Afaict, 3 is a perfectly valid value, meaning 25% of sig-> key recoveries
> would fail erroneously...
> ------------------------------------------------------------------------------
> Is your legacy SCM system holding you back? Join Perforce May 7 to find
> out:
> &#149; 3 signs your SCM is hindering your productivity
> &#149; Requirements for releasing software faster
> &#149; Expert tips and advice for migrating your SCM now
> http://p.sf.net/sfu/perforce_______________________________________________
> Bitcoin-development mailing list
> Bitcoin-development@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
>

Re: [Bitcoin-development] Bug in key.cpp

[Pieter Wuille]

On Tue, May 6, 2014 at 5:12 AM,  <odinn.cyberguerrilla@riseup.net> wrote:
> You are right there is a bug in there.
>
> But the value is not 25% I think.  Tinker some more. :-)
>
>>
>> Afaict, 3 is a perfectly valid value, meaning 25% of sig-> key recoveries
>> would fail erroneously...

Values 2 and 3 are only needed in theory. They together shouldn't
occur more than once in 2**127 (when the signature value is between
the group size and the field size).

That said, this is indeed a bug.

-- 
Pieter