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Library for Shamir Secret Sharing in the Galois Field 2**8
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This library implements what is known as Shamir Secret Sharing. This
entails encoding a secret as an integer and then constructing a
polynomial whose coefficients are random and calculating coordinate
pairs along the resultant curve. These coordinate pairs are considered
'shares' and by controlling the order of the polynomial we can control
the number of shares required to be able to recover the secret.
In this manner we can split a secret into any 'C' shares, any 'T' of
which can be used to recover the secret.
This would be useful, for example, in looking after GPG secret keys
used rarely, but whose security is paramount. For example a key used
to sign the key which signs the Debian or Ubuntu package archives.
If you wish to know more about how the secret sharing works and why it
is safe, then there exist many articles on the mathematics behind it.
This particular implementation was very heavily inspired by the work
of Mark D. Wooding (mdw) in his catacomb library. Thanks go to Mark
for offering to share this implementation with me.
Using the library is very easy. The tests and sample tools are very
straightforward and the header file tells you what each function is
used for.
-- Daniel Silverstone. 2006-01-15
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