ginsburgnm/pyseltongue

Shamir Secret Sharing library

Pyseltongue

A library for sharding and sharing secrets (like Bitcoin private keys), using shamir's secret sharing scheme.

Name

I shamelessly stole this name idea from a coworker, shamir-secret-sharing-service ssss -> parseltongue -> we're in python -> pyseltongue (nagini was already taken)

History Disclaimer

This was initially forked from secret-sharing but they haven't updated the package in 4 years much to many people's dismay. It was getting a little irritating that github kept defaulting to opening merge requests to their repo, even though that will never happen.

The code has been updated to python3 capatibility and I hope it is useful for others.

Installation

>>> pip install pyseltongue

Sample Usage

Hex Secrets

Splitting into shares

>>> from pyseltongue import SecretSharer
>>> shares = SecretSharer.split_secret("c4bbcb1fbec99d65bf59d85c8cb62ee2db963f0fe106f483d9afa73bd4e39a8a", 2, 3)
['1-58cbd30524507e7a198bdfeb69c8d87fd7d2c10e8d5408851404f7d258cbcea7', '2-ecdbdaea89d75f8e73bde77a46db821cd40f430d39a11c864e5a4868dcb403ed', '3-80ebe2cfef5e40a2cdefef0923ee2bb9d04bc50be5ee308788af98ff609c380a']

Recovering from shares

>>> SecretSharer.recover_secret(shares[0:2])
'c4bbcb1fbec99d65bf59d85c8cb62ee2db963f0fe106f483d9afa73bd4e39a8a'

Plaintext Secrets

Splitting into shares

>>> from pyseltongue import PlaintextToHexSecretSharer
>>> shares = PlaintextToHexSecretSharer.split_secret("correct horse battery staple", 2, 3)
['1-7da6b11af146449675780434f6589230a3435d9ab59910354205996f508b8d0d', '2-fb4d6235e28c892cea70367c15ec3cbfed4cf4a417bd01e9812980f3ac97ddc8', '3-78f41350d3d2cdc35f6868c3357fe74f37568bad79e0f39dc04d687808a42d5a']

Recovering from shares

>>> PlaintextToHexSecretSharer.recover_secret(shares[0:2])
'correct horse battery staple'

Bitcoin Private Keys

Note: Bitcoin private keys are in Base58 check format.

Splitting into reliably printable base58 shares

>>> from pyseltongue import BitcoinToB58SecretSharer
>>> shares = BitcoinToB58SecretSharer.split_secret("5KJvsngHeMpm884wtkJNzQGaCErckhHJBGFsvd3VyK5qMZXj3hS", 2, 3)
['2-Bqni1ysZcXhFBhVVJLQgPimDUJrjBrzuvBmc6gPNPh1jyDcvM6uYUuH', '3-9xpMBerBCdHLKzCQ82fjVLfZ3Qt48sqa6nz1E3cc6eu3qUe58vaogU3', '4-85qzMKpnnisRUGuJwivnaxZtcWuP5tgEHQCQMQqqocnMhjfDvkG4t2o']

Recovering from base58 shares

>>> BitcoinToB58SecretSharer.recover_secret(shares[0:2])
'5KJvsngHeMpm884wtkJNzQGaCErckhHJBGFsvd3VyK5qMZXj3hS'

Splitting into reliably transcribable base32 shares

>>> from pyseltongue import BitcoinToB32SecretSharer
>>> shares = BitcoinToB32SecretSharer.split_secret("5KJvsngHeMpm884wtkJNzQGaCErckhHJBGFsvd3VyK5qMZXj3hS", 2, 3)
['B-RJ6Y56OSUWDY5VAAGC6XLSTM64CAJ2LPBNB7NKATJCWC7VSHIP5DQIVMR6OGJ4GB', 'C-CT5R24XAR5B732JWYQKSYOYBSF5VHI73HLY24QCFRJR5XUW64C4JWYN6SRGWVCUG', 'D-T54KX27OPEAGZ7TNK5WOFK4WFPZKEXUHNKPWLWDXZQNYPT3WPV3P5IGQTD7HAJDG']

Recovering from base32 shares

>>> BitcoinToB32SecretSharer.recover_secret(shares[0:2])
'5KJvsngHeMpm884wtkJNzQGaCErckhHJBGFsvd3VyK5qMZXj3hS'  

Splitting into reliably transcribable zbase32 shares

>>> from pyseltongue import BitcoinToZB32SecretSharer
>>> shares = BitcoinToZB32SecretSharer.split_secret("5KJvsngHeMpm884wtkJNzQGaCErckhHJBGFsvd3VyK5qMZXj3hS", 2, 3)
['b-aweuzkm9jmfgd7x4k595bzcm3er3epf4dprfwzpprqa3exbuocs9byn4owfuqbo', 'n-btetgqqu8doacarsbyfdzpyycyj6gfdeaaxrpfx33pdjk4ou1d5owjdmdi1iegm9', 'd-njh33f14q7smucmh8iq8uaewc8mzub3mzptrwsegfiz3hc1fozkkjtguc4trh6sq']

Recovering from zbase32 shares

>>> BitcoinToZB32SecretSharer.recover_secret(shares[0:2])
'5KJvsngHeMpm884wtkJNzQGaCErckhHJBGFsvd3VyK5qMZXj3hS'    

Raw integers

Splitting into shares

>>> from pyseltongue import secret_int_to_points, points_to_secret_int
>>> secret = 88985120633792790105905686761572077713049967498756747774697023364147812997770L
>>> shares = secret_int_to_points(secret, 2, 3)
[(1, 108834987130598118322155382953070549297972563210322923466700361825476188819879L), (2, 12892764390087251114834094135881113029625174256248535119246116278891435001755L), (3, 32742630886892579331083790327379584614547769967814710811249454740219810823864L)]

Recovering from shares

>>> points_to_secret_int(shares[0:2])
88985120633792790105905686761572077713049967498756747774697023364147812997770L

Custom formats

Splitting into shares

>>> from pyseltongue import SecretSharer, base64_chars
>>> sharer_class = SecretSharer
>>> sharer_class.share_charset = base64_chars
>>> shares = sharer_class.split_secret("c4bbcb1fbec99d65bf59d85c8cb62ee2db963f0fe106f483d9afa73bd4e39a8a", 2, 3)
['B-JpxCTUQ9D+q93JglQM9yRinI2Cyxe92FTBSYa93ppfY', 'C-HAmR0pjHuHwL4rozXnFY05ysIJVqtf3pob1HCMaaZUm', 'D-EXbhV+1SYQ1Z6NxBfBM/YQ+PaP4j8B5N92X1pa9LJJ0']

Recovering from shares

>>> sharer_class.recover_secret(shares[0:2])
'c4bbcb1fbec99d65bf59d85c8cb62ee2db963f0fe106f483d9afa73bd4e39a8a'