factom-identity-lib/src/crypto.js

Library to read and update Factom identities

const sha256 = require('hash.js/lib/hash/sha/256'),
    sign = require('tweetnacl/nacl-fast').sign;

function sha256d(data) {
    return Buffer.from(
        sha256()
            .update(
                sha256()
                    .update(data)
                    .digest()
            )
            .digest()
    );
}

function secretToPublicKey(secret) {
    const key = sign.keyPair.fromSeed(secret);
    return Buffer.from(key.publicKey);
}

module.exports = {
    sha256d,
    secretToPublicKey
};