Re: LibTomCrypt [v0.99] and LibTomMath [v0.32]

From: Tom St Denis (tomstdenis_at_iahu.ca)
Date: 10/30/04 

Date: Fri, 29 Oct 2004 23:10:03 -0400

Tom St Denis wrote:
> Tom St Denis wrote:
>
>> Both released today ;-)
>
>
> So close...
>
> There is actually a bug in my RSA export. one of the terms is (1/q mod
> p) * q mod N and should be 1/q mod p. I computer it as the former for
> CRT... The fix is to either divide [mod N] or change my RSA's CRT to
> the other form...
>
> I'll have a patch in an hour.

I've decided to just re-release 0.99 since I want to make sure people
grab it [people seem to avoid patchsets...]

I explained this in

http://libtomcrypt.org/ltc-0.99-note.txt.asc

And you can fetch the library directly from

http://libtomcrypt.org/files/crypt-0.99.zip
http://libtomcrypt.org/files/crypt-0.99.tar.bz2

To make sure you have the right copy...

d726e7fc495353935b5c1914d62ecbfe crypt-0.99.tar.bz2
80850966981fbdd4518d05bad825840e crypt-0.99.zip

Essentially the fix I chose was to implement CRT the way RSA does it so
that I don't have to convert params/etc. I've tested it with the
standard makefile and the new shared object and it works fine [via
demos/test]. Only issue I noted was that the small "mp_div()"
alternative seems to cause problems [my bet is it doesn't range properly
but gets the congruence right]. I just turned it disabled it [it's not
required].

So in a nutshell the bug was I didn't quite export true RSA key packets
and the fix was to actually export them ;-)

Tom

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