crypto splitting program

[Colin Watson]

On Tue, Jan 11, 2005 at 08:58:35PM -0500, David Mandelberg wrote:
> Does anybody know of a program that can split a file into n files such that to
> recreate the original file, m parts are necessary?
> 
> This is done in crypto using the concept that you have a  y = f(x) graph where
> the original file is the y intercept and the degree is m - 1. Each separate file
> is one point on the function, and once you have m points (files), the y
> intercept (original file) can be computed. until m -1 files are useless however,
> because the y intercept could still be anywhere.
> 
> The math behind that, while possible to do by hand, is difficult, and apt-cache
> search didn't show anything that would do that.

Although I haven't tried it yet, this seems to be exactly what you want:

  http://www.mindrot.org/files/secsplit-1.2.tar.gz

Cheers,

-- 
Colin Watson                                    [cjwatson at canonical.com]