Java Threshold Secret Sharing

Description

Core implementation of Threshold Secret Sharing (TSS) http://tools.ietf.org/html/draft-mcgrew-tss-03 It uses a finite field GF(256) instead of Shamir scheme using large integers modulo a large prime number. Max number of shares is 255, max secret key bytes is 65535.

KISS code

Tested code

Requirements

Java 1.7

Compile, Test & Package

$ mvn package

Example

ThresholdSecretSharing tss = new ThresholdSecretSharing();

// Create 5 shares, secret recoverable from at least 3 different shares

byte[] secret = Hex.convert("7465737400");
byte[][] shares = tss.createShares(secret, 5, 3, new SecureRandom());

// Recover secret from 3 shares

byte[] recoveredSecret = tss.recoverSecret(shares[0], shares[2], shares[3]);

Assert.assertArrayEquals(recoveredSecret, secret);

License

MIT License