seifnode
Node.js Implementation of Seif Crypto Modules
Getting Started
From your project directory, run (see below for requirements):
$ npm install seifnode
Seifnode depends on the c++ library Seifrng which will be installed locally during pre-install; Seifrng uses the CMake build system which too will be installed locally if not found. The node module also depends of Crypto++ which will be locally installed by Seifrng if not found during pre-install.
On Linux systems the node module requires PatchELF utility which will be installed locally if not found during pre-install.
Alternatively, to use the latest development version from Github:
$ npm install https://github.com/paypal/seifnode.git
Test
Please refer to the "test" directory to view the "mocha" unit tests. To run the tests, please run the following command from the top-level directory.
$ npm test
Examples
Please refer to the "examples" directory to see examples of how to use the various modules.
Interface
The module exposes four different interfaces useful for different purposes.
1. RNG
This module exposes the ISAAC random number generator to node.js from the c++ library seifrng. We haven't made any changes to the random number generation process as such. The only enhancement is that we are accessing the random number generator state and encrypting it before persisting it to the disk.
Initialization:
let seifnode = require("seifnode");
let seifrng = seifnode.RNG();Usage:
The functions exposed are as follows:
function isInitialized(key, filename, function callback(result){...})
Creates an async worker to check if the RNG has been initialized by checking if the state file exists and can be decrypted using the given key. Once the async work is complete, the RNG is initialized with the state on the disk if present or an appropriate error is given to the callback.
seifrng.isInitialized(key, filename, function(result) {
console.log(result.code);
console.log(result.message);
});
// 'key' is a buffer containing the disk encryption/decryption key
// 'filename' is the name of the RNG saved state file on disk
// 'result' is an object containing the code('code') and message('message')function initialize(key, filename)
Initilizes the RNG by gathering entropy from the available sources (Please look at the "rng" repo for more details at <>). Once the entropy generation is complete, the RNG is initialized using the generated seed and it is ready to be used.
seifrng.initialize(key, filename);
// 'key' is a buffer containing the disk encryption/decryption key
// 'filename' is the name of the RNG saved state file on diskfunction getBytes(n)
Gets the number of random bytes required and returns a buffer with the random output. If the RNG has not been initialized an error will be thrown.
let numbytes = 32;
let buffer = seifrng.getBytes(numBytes);
// 'numBytes' is the number of required random bytes
// 'buffer' is a node.js bufferfunction saveState()
Encrypts and saves the RNG state to disk.
seifrng.saveState(function(result) {
console.log(result.code);
console.log(result.message);
});function destroy()
Destroys the underlying RNG object thus saving the state to disk.
seifrng.destroy();2. ECC
This module is responsible for exposing Crypto++ ECC functions using our implementation of isaac random number generator.
Initialization:
let seifnode = require("seifnode");
let seifecc = seifnode.ECC(diskKey, folder);
// 'diskKey' is the key used to encrypt the keys and rng state
// 'folder' is the folder where the keys and rng state are saved on diskUsage:
The functions exposed are as follows:
function loadKeys()
Creates an async worker to load keys from the disk (encrypted using the key provided during initialization) and invokes the callback function with the error object (if applicable) and/or the object containing the keys.
seifecc.loadKeys(function(status, keys) {
// 'status' (if applicable) is of the form: {code: [statusCode], message: [statusMessage]}
console.log(status);
// 'keys' (if available) is of the form: {enc: [publicKey], dec: [privateKey]}
console.log(keys);
});function generateKeys()
Initializes the isaac RNG and uses it to generate the public/private keys and return them to the caller. These keys are also encrypted and saved to the disk.
let keys = seifecc.generateKeys();
// 'keys' (if available) is of the form: {enc: [publicKey], dec: [privateKey]}function encrypt(publicKey, message)
Encrypts the message buffer using the public key to return the cipher string (We are using Cryptopp ECIES for this purpose and the curve used is the NIST approved SECP521r1).
seifecc.loadKeys(function(status, keys) {
if (status === undefined && keys !== undefined) {
let cipher = obj.encrypt(keys.enc, message);
// 'keys.enc' is the string containing the hex encoded ECC public key
// 'message' is the buffer containing the message to be encrypted
// 'cipher' is a buffer containing the encrypted cipher
}
});function decrypt(privateKey, cipher)
Decrypts the cipher buffer using the private key to return the original message buffer (We are using Cryptopp ECIES for this purpose and the curve used is the NIST approved SECP521r1).
seifecc.loadKeys(function(status, keys) {
if (status === undefined && keys !== undefined) {
let message = seifecc.decrypt(keys.dec, cipher);
// 'keys.dec' is the string containing the hex encoded ECC private key
// 'cipher' is the buffer containing the cipher to be decrypted
// 'message' is the buffer containing the decrypted message
}
});3. AESXOR
This module is responsible for exposing our implementation of link encryption. We are exposing the Cryptopp AES implementation in the GCM mode with slight modifications to enhance security as explained below. Similary, after the cipher bytes have been decrypted they are XOR'd with XORShift+ random bytes to get the original message.
Initialization:
let seifnode = require("seifnode");
let seifaes = seifnode.AESXOR(seed);
// 'seed' is a buffer containing bytes representing the uint64 pcg seedUsage:
The functions exposed are as follows:
function encrypt(key, message)
Encrypts the message using the given key to return the cipher. As part of this process, the message bytes are first XOR'd with equal number of random bytes generated using XORShift+ and then encrypted using the AES-GCM mode.
let cipher = seifaes.encrypt(key, message);
// 'key' is the buffer containing the AES key
// 'message' is the buffer containing the message to be encrypted
// 'cipher' is the buffer containing the encrypted cipherfunction decrypt(key, cipher)
Decrypts the cipher to return the original message. As part of this process, after the cipher bytes have been decrypted using the AES-GCM mode, the decrypted buffer is XOR'd with as many XORShift+ random bytes to get the original message.
let message = seifaes.decrypt(key, cipher);
// 'key' is the buffer containing the AES key
// 'cipher' is the buffer containing the cipher to be decrypted
// 'message' is the buffer containing the decrypted message4. SEIFSHA3
This module is responsible for exposing Crypto++ SHA3 function
Initialization:
let seifnode = require("seifnode");
let seifsha3 = seifnode.SEIFSHA3();Usage:
The functions exposed are as follows:
function hash(data)
Gets the string data and returns the hash (using Cryptopp implementation of SHA3-256) of the given input as a buffer object.
let hash = seifsha3.hash(stringData);
// 'stringData' is the string data to be hashed
// 'hash' is the output buffer containing the SHA3-256 hashDependencies
1. Seifrng
For generating cryptographically secure random numbers.
License: https://github.com/paypal/seifrng/blob/master/LICENSE.md
2. CryptoPP/Crypto++
Used for all cryptographic functions. Library installed version 5.6.5
License: Crypto++ Library is copyrighted as a compilation and (as of version 5.6.5) licensed under the Boost Software License 1.0, while the individual files in the compilation are all public domain. https://www.cryptopp.com/License.txt
3. Node modules: nan
This is basically a header file containing macros and utilities to store all logic necessary to develop native Node.js addons without having to inspect NODE_MODULE_VERSION
License & copyright: https://github.com/nodejs/nan/blob/master/LICENSE.md
License
The MIT License (MIT)
Copyright (c) 2015, 2016, 2017 PayPal
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.