README.md

Secret: Shamir's Secret Sharing with Asymmetric Encryption Library

Overview

This library offers a seamless integration for applying Shamir's Secret Sharing Scheme combined with asymmetric encryption. The provided demo shows how users can generate a key pair, encrypt tabular data into shares, and then reconstruct the table from these shares.

Features

1. Key Generation: Generate a public-private key pair to be used for asymmetric encryption.
2. Encrypt Tabular Data: Convert table data (in JSON format) into encrypted shares.
3. Reconstruct Data: Decrypt the shared data to retrieve the original table.

Example usage

The library takes any shape of JSON. The JSON can be arbitrarily nested and deep, but leaf values must be numbers.

Example data in the form of JSON:

data = [
    {
        "row0":[41,79,48,8,18],
        "row1":[55,87,53,67,49],
        "row2":[37,91,82,89,74]
    }
]

Example order of operations:

import { tableToSecretShares, generateKeyPair, secretSharesToTable } from 'secret';
import { keyPairToDictionary } from 'secret';
import { BigNumber } from 'bignumber.js';

const keyPair = await generateKeyPair();
const publicKey = keyPair.publicKey;
const privateKey = keyPair.privateKey;
const table = JSON.parse(data);
const numShares = 3
const threshold = 2
const numEncryptWithKey 3
const prime = new BigNumber(prime);

// Transform each cell of the table into a set of secret shares
encryptedShares = await tableToSecretShares(
    table,
    numShares,
    threshold,
    numEncryptWithKey,
    publicKey,
    prime
);

// Now you can distribute the encrypted shares to the other parties.
// numEncryptWithKey should be less than numShares if you want other parties to compute on the shares.
// The other parties must also know the prime number used to generate the shares.

// You must implement your own functionality for distributing and collecting shares.

// Custom math operation for aggregating values under Shamir's
const reduce = (value) => value;

// Optional progress bar function
const progressBar = (value) => {};

// Custom function to apply to each secret value before reducing
const transform = (value) => value;

const table = await secretSharesToTable(
    encryptedShares,
    privateKey,
    prime,
    reduce,
    progressBar,
    transform
);