shamira 1.0

Shamir's secret sharing implementation. Splitting and joining secrets.

Shamira

Implements Shamir's secret sharing algorithm. Splits a string or a byte sequence byte-per-byte into n<255 shares, with any k of them sufficient for reconstruction of the original input.

Outputs the shares as hexadecimal, Base32 or Base64 encoded strings.

Installation

From pip

Run pip install shamira.

From the source

Can be run straight from the cloned repository by executing the package with python -m shamira or built with python -m build and installed with pip install dist/shamira*.whl.

Usage

As a CLI application

Run shamira split ... for splitting and shamira join ... for joining the shares back. Appending --help will show you the documentation.

As a library

from shamira import generate, generate_raw, reconstruct, reconstruct_raw

help(function) will show the documentation.

Issue tracker

Please report your issues to https://trac.19x19.cz/shamira/report

Performance

Being written in pure Python, the code is not especially fast. It is therefore recommended to split rather keys to encrypted files than the files themselves.

Benchmark results, as obtained by running shamira benchmark. All values mean seconds per byte of the secret length:

k / n parameters	Split	Join
2 / 3 (a Raspberry Pi 3)	0.000142	0.000448
2 / 3 (a laptop)	7.88e-06	4.28e-05
254 / 254 (a Raspberry Pi 3)	0.0268	0.0287
254 / 254 (a laptop)	0.00183	0.00156

License

The code is licensed under GNU GPL v3. If this doesn't fit your needs, reach me and we can negotiate relicensing.