tweetnacl-ts

TweetNaCl in TypeScript (and ES6)

Port of TweetNaCl.js to TypeScript with several API changes for compatibility with Tree-Shaking to help modern JavaScript bundlers like Rollup and Webpack >2.x attain much optimization.

Also includes:

• TweetNaCl-Auth.js
• TweetNaCl-Utils.js
• BlakeJS
• TweetNaCl-SealedBox.js

NOTE: May be you need crypto.getRandomValues() polyfill for browsers which doesn't supported it.

Documentation

• Overview
• Usage
  • Public-key authenticated encryption (box)
  • Secret-key authenticated encryption (secretbox)
  • Scalar multiplication
  • Signatures
  • Hashing
  • Random bytes generation
  • Constant-time comparison
• System requirements
• Development and testing

Overview

Originally this project had been a port of nacl-fast.js to TypeScript. Now it also includes support of SealedBox and HMAC-Auth.

Usage

All API functions accept and return bytes as ByteArrays (natively as Uint8Arrays). If you need to encode or decode strings, use functions encodeUTF8/decodeUTF8.

Public-key authenticated encryption (box)

Implements x25519-xsalsa20-poly1305.

box_keyPair()

Generates a new random key pair for box and returns it as an object with publicKey and secretKey members:

interface BoxKeyPair {
    publicKey: ByteArray; // Array with 32-byte public key
    secretKey: ByteArray; // Array with 32-byte secret key
}

box_keyPair_fromSecretKey(secretKey)

Returns a key pair for box with public key corresponding to the given secret key.

box(message, nonce, theirPublicKey, mySecretKey)

Encrypts and authenticates message using peer's public key, our secret key, and the given nonce, which must be unique for each distinct message for a key pair.

Returns an encrypted and authenticated message, which is BoxLength.Overhead longer than the original message.

box_open(box, nonce, theirPublicKey, mySecretKey)

Authenticates and decrypts the given box with peer's public key, our secret key, and the given nonce.

Returns the original message, or undefined if authentication fails.

box_before(theirPublicKey, mySecretKey)

Returns a precomputed shared key which can be used in box_after and box_open_after.

box_after(message, nonce, sharedKey)

Same as box, but uses a shared key precomputed with box_before.

box_open_after(box, nonce, sharedKey)

Same as box_open, but uses a shared key precomputed with box_before.

Constants

BoxLength.PublicKey = 32

Length of public key in bytes.

BoxLength.SecretKey = 32

Length of secret key in bytes.

BoxLength.SharedKey = 32

Length of precomputed shared key in bytes.

BoxLength.Nonce = 24

Length of nonce in bytes.

BoxLength.Overhead = 16

Length of overhead added to box compared to original message.

Secret-key authenticated encryption (secretbox)

Implements xsalsa20-poly1305.

secretbox(message, nonce, key)

Encrypts and authenticates message using the key and the nonce. The nonce must be unique for each distinct message for this key.

Returns an encrypted and authenticated message, which is SecretBox.Overhead longer than the original message.

secretbox_open(box, nonce, key)

Authenticates and decrypts the given secret box using the key and the nonce.

Returns the original message, or undefined if authentication fails.

Constants

SecretBoxLength.Key = 32

Length of key in bytes.

SecretBoxLength.Nonce = 24

Length of nonce in bytes.

SecretBoxLength.Overhead = 16

Length of overhead added to secret box compared to original message.

Sealed box encryption

Sealed boxes are designed to anonymously send messages to a recipient given its public key.

sealedbox(message, publicKey)

Encrypts message using the recipient's public key.

Returns an encrypted message, which is SealedBox.Overhead longer than the original message.

sealedbox_open(box, publicKey, secretKey)

Decrypts the given sealed box using the recipient's key pair.

Returns the original message, or undefined if decryption fails.

Constants

SealedBoxLength.PublicKey = 32

Length of public key of recipient in bytes.

SealedBoxLength.SecretKey = 32

Length of secret key of recipient in bytes.

SealedBoxLength.Nonce = 24

Length of nonce in bytes.

SealedBoxLength.Overhead = 48

Length of overhead added to box compared to original message.

Scalar multiplication

Implements x25519.

scalarMult(n, p)

Multiplies an integer n by a group element p and returns the resulting group element.

scalarMult_base(n)

Multiplies an integer n by a standard group element and returns the resulting group element.

Constants

ScalarMultLength.Scalar = 32

Length of scalar in bytes.

ScalarMultLength.GroupElement = 32

Length of group element in bytes.

Signatures

Implements ed25519.

sign_keyPair()

Generates new random key pair for signing and returns it as an object with publicKey and secretKey members:

interface SignKeyPair {
    publicKey: ByteArray; // Array with 32-byte public key
    secretKey: ByteArray; // Array with 64-byte secret key
}

sign_keyPair_fromSecretKey(secretKey)

Returns a signing key pair with public key corresponding to the given 64-byte secret key. The secret key must have been generated by sign_keyPair or sign_keyPair_fromSeed.

sign_keyPair_fromSeed(seed)

Returns a new signing key pair generated deterministically from a 32-byte seed. The seed must contain enough entropy to be secure. This method is not recommended for general use: instead, use sign_keyPair to generate a new key pair from a random seed.

sign(message, secretKey)

Signs the message using the secret key and returns a signed message.

sign_open(signedMessage, publicKey)

Verifies the signed message and returns the message without signature.

Returns undefined if verification failed.

sign_detached(message, secretKey)

Signs the message using the secret key and returns a signature.

sign_detached_verify(message, signature, publicKey)

Verifies the signature for the message and returns true if verification succeeded or false if it failed.

Constants

SignLength.PublicKey = 32

Length of signing public key in bytes.

SignLength.SecretKey = 64

Length of signing secret key in bytes.

SignLength.Seed = 32

Length of seed for sign_keyPair_fromSeed in bytes.

SignLength.Signature = 64

Length of signature in bytes.

Hashing

Implements SHA-512.

hash(message)

Returns SHA-512 hash of the message.

Constants

HashLength.Hash = 64

Length of hash in bytes.

Authenticating

Implements HMAC-SHA-512-256

auth(message, key)

Authenticates the given message with the secret key. (In other words, returns HMAC-SHA-512-256 of the message under the key.)

auth_full(message, key)

Returns HMAC-SHA-512 (without truncation) of the message under the key

AuthLength.Auth = 32

Length of authenticator returned by auth.

AuthLength.AuthFull = 64

Length of authenticator returned by auth_full.

AuthLength.Key = 32

Length of key for auth and auth_full (key length is currently not enforced).

Random bytes generation

randomBytes(length)

Returns a ByteArray of the given length containing random bytes of cryptographic quality.

Implementation note

TweetNaCl.js uses the following methods to generate random bytes, depending on the platform it runs on:

• window.crypto.getRandomValues (WebCrypto standard)
• window.msCrypto.getRandomValues (Internet Explorer 11)
• crypto.randomBytes (Node.js)

If the platform doesn't provide a suitable PRNG, the following functions, which require random numbers, will throw exception:

• randomBytes
• box_keyPair
• sign_keyPair

Other functions are deterministic and will continue working.

Constant-time comparison

verify(x, y)

Compares x and y in constant time and returns true if their lengths are non-zero and equal, and their contents are equal.

Returns false if either of the arguments has zero length, or arguments have different lengths, or their contents differ.

System requirements

TweetNaCl.js supports modern browsers that have a cryptographically secure pseudorandom number generator and typed arrays, including the latest versions of:

• Chrome
• Firefox
• Safari (Mac, iOS)
• Internet Explorer 11

Other systems:

• Node.js

Development and testing

Install NPM modules needed for development:

$ npm install

To build js run compilation:

$ npm run compile

Testing

To run tests in Node:

$ npm run test-node

To run tests in browsers and Node (CI-mode):

$ npm run test

To run tests in browsers and Node (Dev-mode):

$ npm run test-dev