ssss is an implementation of Shamir's secret sharing scheme for
UNIX/linux machines. It is free software, the code is licensed under
the GNU GPL. ssss does both: the generation of shares for a known
secret and the reconstruction of a secret using user provided shares.
The software was written in 2006 by B. Poettering, it links against
the GNU libgmp  multiprecision library (version 4.1.4 works well)
and requires the /dev/random entropy source.

WWW: http://point-at-infinity.org/ssss/