tno.mpc.encryption-schemes.shamir 1.1.0

Implementation of Shamir secret sharing

TNO MPC Lab - Encryption Schemes - Shamir

The TNO MPC lab consists of generic software components, procedures, and functionalities developed and maintained on a regular basis to facilitate and aid in the development of MPC solutions. The lab is a cross-project initiative allowing us to integrate and reuse previously developed MPC functionalities to boost the development of new protocols and solutions.

The package tno.mpc.encryption_schemes.shamir is part of the TNO Python Toolbox.

Limitations in (end-)use: the content of this software package may solely be used for applications that comply with international export control laws.
This implementation of cryptographic software has not been audited. Use at your own risk.

Documentation

Documentation of the tno.mpc.encryption_schemes.shamir package can be found here.

Install

Easily install the tno.mpc.encryption_schemes.shamir package using pip:

$ python -m pip install tno.mpc.encryption_schemes.shamir

If you wish to run the tests you can use:

$ python -m pip install 'tno.mpc.encryption_schemes.shamir[tests]'

Note:

A significant performance improvement can be achieved by installing the GMPY2 library.

$ python -m pip install 'tno.mpc.encryption_schemes.shamir[gmpy]'

Usage

The shamir secret sharing module can be used as follows:

from tno.mpc.encryption_schemes.shamir import ShamirSecretSharingScheme, ShamirShares

# Initialize a three-out-of-five secrect sharing scheme with prime 10657
# Note: the polynomial degree is one less than the number of parties needed for reconstruction
shamir_scheme = ShamirSecretSharingScheme(10657, 5, 2)
# Share a secret integer
sharing = shamir_scheme.share_secret(42)
# When receiving shares a reconstructor can be created as follows
reconstructor = ShamirShares(
    shamir_scheme, {1: sharing.shares[1], 2: sharing.shares[2], 3: sharing.shares[3]}
)
# Reconstruct the secret and check if it is the expected result
assert 42 == sharing.reconstruct_secret() == reconstructor.reconstruct_secret()