etkframework/crypto_lib/seedCrypt.js

First test release of Etk over colored coins SDK

/**
 * Etk Helper library.
 * Encryption and decryption of HD Wallet seed over server without knowledge of seed.
 * 
 * Copyright (C) 2015  Akul Mathur

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
    
    Parts of the software are provided under separate licenses, as follows:
    "colu-nodejs" SDK is under the MIT License 
    "pbkdf2-sha256" is under the BSD License 
    "bip38" is under the MIT License 
    "scryptsy" is under the MIT License 
    "coinstring" is under the MIT License
   
 * Core Developer(s): @codecakes Akul Mathur
 * Maintainer(s):
 *              @codecakes Akul Mathur
 */ 


"use strict";

const
    compoundedSalt = require("./passCrypt").compoundedSalt,
    hashCipherText = require("./kdfCrypt").hashCipherText,
    hashedLen = require("./kdfCrypt").hashedLen,
    encrypt = require("./kdfCrypt").encrypt,
    decrypt = require("./kdfCrypt").decrypt,
    encryptSeed = function encryptSeed(masterpassword, seed, ivInputs, bufInputs, storeCB) {
        
        ivInputs.unshift(masterpassword);
        bufInputs.unshift(masterpassword);
        
        const
            ivSalt = ( hashedLen( hashCipherText( masterpassword, compoundedSalt.apply(this,ivInputs) ) ) ),
            bufSalt = ( hashedLen( hashCipherText( masterpassword, compoundedSalt.apply(this,bufInputs) ) ) );
        encrypt(masterpassword, seed, ivSalt, bufSalt, function cb(err, cipherText, iv) {
            if (err) throw Error(err);
            // this stores the transformed seed
            storeCB(cipherText, iv);
        });
    },
    decryptSeed = function decryptSeed(masterpassword, cipherText, iv, bufInputs, getCB) {
        
        bufInputs.unshift(masterpassword);
        
        let 
            bufSalt = hashedLen( hashCipherText( masterpassword, compoundedSalt.apply(this,bufInputs) ) );
        
        decrypt( masterpassword, bufSalt, cipherText, iv, 
                   function cbDecrypt( err, decipherText ) {
                       if (err) throw Error(err);
                       getCB(decipherText.toString('utf8'));
                   });
    };

exports.encryptSeed = encryptSeed;
exports.decryptSeed = decryptSeed;

// for testing and debugging purpose only

// const
//     // 256 char long
//     seed = 'c82425d18a88ea6c5a92d06bc4ee26bfaf1b8782e7c0537544ae6dd40bb5083bxprv9s21ZrQH143K4EdfsuwWHdxaGgcwGkTB1f71fbzJNfJma1Xga5XE3LqYxXKkwJJLevsp16iDRyk35MwvmKEEyyqLkHQVziTNs6VtPr1xGM81',
//     masterpassword = "HaiIsPass";
// let
//     ivInputs = ["band", "ho", "gaya",  "Nee"],
//     bufInputs = ["jhona", "launa"],
//     ivSalt = ( hashedLen( hashCipherText( masterpassword, compoundedSalt.apply(this,ivInputs) ) ) ),
//     bufSalt = ( hashedLen( hashCipherText( masterpassword, compoundedSalt.apply(this,bufInputs) ) ) );
    
//     encryptSeed(masterpassword, seed, ivInputs, bufInputs, function storeCB(cipherText, iv) {
//         console.log("Cipher text is: "+ cipherText);
//         ivInputs = ["band", "ho", "gaya",  "Nee"],
//         bufInputs = ["jhona", "launa"],
//         decryptSeed(masterpassword, cipherText, iv, bufInputs, function(DecipheredText) {
//             console.log("DecipheredText: "+ DecipheredText);
//         });
//     });