https://github.com/lapets/shamirs
Minimal pure-Python implementation of Shamir's secret sharing scheme.
https://github.com/lapets/shamirs
cryptography library mpc multi-party-computation multiparty-computation python python-library secret-sharing secure-mpc secure-multiparty-computation shamir-secret-sharing shamirs-secret-sharing
Last synced: 8 months ago
JSON representation
Minimal pure-Python implementation of Shamir's secret sharing scheme.
- Host: GitHub
- URL: https://github.com/lapets/shamirs
- Owner: lapets
- License: mit
- Created: 2018-01-10T03:08:25.000Z (about 8 years ago)
- Default Branch: main
- Last Pushed: 2025-01-02T00:17:14.000Z (about 1 year ago)
- Last Synced: 2025-06-09T01:44:32.267Z (9 months ago)
- Topics: cryptography, library, mpc, multi-party-computation, multiparty-computation, python, python-library, secret-sharing, secure-mpc, secure-multiparty-computation, shamir-secret-sharing, shamirs-secret-sharing
- Language: Python
- Homepage: https://pypi.org/project/shamirs
- Size: 88.9 KB
- Stars: 12
- Watchers: 1
- Forks: 4
- Open Issues: 0
-
Metadata Files:
- Readme: README.rst
- License: LICENSE
Awesome Lists containing this project
README
=======
shamirs
=======
Minimal pure-Python implementation of `Shamir's secret sharing scheme `__.
|pypi| |readthedocs| |actions| |coveralls|
.. |pypi| image:: https://badge.fury.io/py/shamirs.svg#
:target: https://badge.fury.io/py/shamirs
:alt: PyPI version and link.
.. |readthedocs| image:: https://readthedocs.org/projects/shamirs/badge/?version=latest
:target: https://shamirs.readthedocs.io/en/latest/?badge=latest
:alt: Read the Docs documentation status.
.. |actions| image:: https://github.com/lapets/shamirs/workflows/lint-test-cover-docs/badge.svg#
:target: https://github.com/lapets/shamirs/actions/workflows/lint-test-cover-docs.yml
:alt: GitHub Actions status.
.. |coveralls| image:: https://coveralls.io/repos/github/lapets/shamirs/badge.svg?branch=main
:target: https://coveralls.io/github/lapets/shamirs?branch=main
:alt: Coveralls test coverage summary.
Purpose
-------
.. |secrets_token_bytes| replace:: ``secrets.token_bytes``
.. _secrets_token_bytes: https://docs.python.org/3/library/secrets.html#secrets.token_bytes
This library provides functions and data structures for computing secret shares given an integer input value and for reassembling an integer from its corresponding secret shares via Lagrange interpolation over finite fields (according to `Shamir's secret sharing scheme `__). The built-in |secrets_token_bytes|_ function and rejection sampling are used to generate random coefficients. The `lagrange `__ library is used for Lagrange interpolation.
Installation and Usage
----------------------
This library is available as a `package on PyPI `__:
.. code-block:: bash
python -m pip install shamirs
The library can be imported in the usual way:
.. code-block:: python
import shamirs
Examples
^^^^^^^^
The library provides functions for transforming a nonnegative integer value into a number of secret shares and for reassembling those shares back into the value they represent:
.. code-block:: python
>>> ss = shamirs.shares(123, quantity=3)
>>> len(ss)
3
>>> shamirs.interpolate(ss)
123
>>> ss = shamirs.shares(456, quantity=20, modulus=15485867, threshold=10)
>>> shamirs.interpolate(ss[5:15], threshold=10)
456
Addition of shares and multiplication of shares by a scalar are both supported:
.. code-block:: python
>>> (r, s, t) = shamirs.shares(123, 3)
>>> (u, v, w) = shamirs.shares(456, 3)
>>> shamirs.interpolate([r + u, s + v, t + w])
579
>>> (r, s, t) = shamirs.shares(123, 3)
>>> r = r * 2
>>> s = s * 2
>>> t = t * 2
>>> shamirs.interpolate([r, s, t])
246
Development
-----------
All installation and development dependencies are fully specified in ``pyproject.toml``. The ``project.optional-dependencies`` object is used to `specify optional requirements `__ for various development tasks. This makes it possible to specify additional options (such as ``docs``, ``lint``, and so on) when performing installation using `pip `__:
.. code-block:: bash
python -m pip install ".[docs,lint]"
Documentation
^^^^^^^^^^^^^
The documentation can be generated automatically from the source files using `Sphinx `__:
.. code-block:: bash
python -m pip install ".[docs]"
cd docs
sphinx-apidoc -f -E --templatedir=_templates -o _source .. && make html
Testing and Conventions
^^^^^^^^^^^^^^^^^^^^^^^
All unit tests are executed and their coverage is measured when using `pytest `__ (see the ``pyproject.toml`` file for configuration details):
.. code-block:: bash
python -m pip install ".[test]"
python -m pytest -W ignore::UserWarning
Alternatively, all unit tests are included in the module itself and can be executed using `doctest `__:
.. code-block:: bash
python src/shamirs/shamirs.py -v
Style conventions are enforced using `Pylint `__:
.. code-block:: bash
python -m pip install ".[lint]"
python -m pylint src/shamirs
Contributions
^^^^^^^^^^^^^
In order to contribute to the source code, open an issue or submit a pull request on the `GitHub page `__ for this library.
Versioning
^^^^^^^^^^
Beginning with version 1.0.0, the version number format for this library and the changes to the library associated with version number increments conform with `Semantic Versioning 2.0.0 `__.
Publishing
^^^^^^^^^^
This library can be published as a `package on PyPI `__ via the GitHub Actions workflow found in ``.github/workflows/build-publish-sign-release.yml`` that follows the `recommendations found in the Python Packaging User Guide `__.
Ensure that the correct version number appears in ``pyproject.toml``, and that any links in this README document to the Read the Docs documentation of this package (or its dependencies) have appropriate version numbers. Also ensure that the Read the Docs project for this library has an `automation rule `__ that activates and sets as the default all tagged versions.
To publish the package, create and push a tag for the version being published (replacing ``?.?.?`` with the version number):
.. code-block:: bash
git tag ?.?.?
git push origin ?.?.?