secret-sharing-dart

Warning: This implementation has not been tested in production nor has it been examined by a security audit. All uses are your own responsibility.

This library is an implementation of Shamir's Secret Sharing Algorithm. It also uses the Converter and Codec framework of dart:convert.

To encode a secret, first import the library:

import 'package:secret_sharing/secret_sharing.dart';

If you want to encode an int-Secret, you'll have to use the RawShareCodec. Otherwise, use the StringShareCodec.

Usage of the RawShareCodec

Encoding

var codec = new RawShareCodec(3, 2);
var shares = codec.encode(900000000000000);

This produces shares in the form of x-y, where x and y are hex values.

Decoding

var decoded = codec.decode(shares);

This should reproduce the secret int (if the number of given shares is sufficient).

Usage of the StringShareCodec

Encoding

The StringShareCodec needs a charset as initialization parameter. If you want to use an adaptive charset based on the secret you want to encode then use the bySecret-Constructor. Otherwise, pass the Charset to the constructor (an included Charset is the ASCIICharset).

Having obtained the codec, you can encode and decode like described before.

Decoding

Decoding works the same as for RawShares.

Command Line Tools

For the command line, there are two tools: The secret_encoder and the secret_decoder. Those tools enable quick access for share generation and secret recovering and have both an included help via --help.

Btw, this library is compatible to flower-pot's Ruby implementation of Shamir's Secret Sharing.