--- /dev/null
+TweetNaCl.js
+============
+
+Port of [TweetNaCl](http://tweetnacl.cr.yp.to) / [NaCl](http://nacl.cr.yp.to/)
+to JavaScript for modern browsers and Node.js. Public domain.
+
+[
+](https://travis-ci.org/dchest/tweetnacl-js)
+
+[Demo](https://dchest.github.io/tweetnacl-js/)
+
+**:warning: Beta version. The library is stable and API is frozen, however
+it has not been independently reviewed. If you can help reviewing it, please
+[contact me](mailto:dmitry@codingrobots.com).**
+
+Documentation
+=============
+
+* [Overview](#overview)
+* [Installation](#installation)
+* [Usage](#usage)
+ * [Public-key authenticated encryption (box)](#public-key-authenticated-encryption-box)
+ * [Secret-key authenticated encryption (secretbox)](#secret-key-authenticated-encryption-secretbox)
+ * [Scalar multiplication](#scalar-multiplication)
+ * [Signatures](#signatures)
+ * [Hashing](#hashing)
+ * [Random bytes generation](#random-bytes-generation)
+ * [Constant-time comparison](#constant-time-comparison)
+ * [Utilities](#utilities)
+* [Examples](#examples)
+* [System requirements](#system-requirements)
+* [Development and testing](#development-and-testing)
+* [Contributors](#contributors)
+* [Who uses it](#who-uses-it)
+
+
+Overview
+--------
+
+The primary goal of this project is to produce a translation of TweetNaCl to
+JavaScript which is as close as possible to the original C implementation, plus
+a thin layer of idiomatic high-level API on top of it.
+
+There are two versions, you can use either of them:
+
+* `nacl.js` is the port of TweetNaCl with minimum differences from the
+ original + high-level API.
+
+* `nacl-fast.js` is like `nacl.js`, but with some functions replaced with
+ faster versions.
+
+
+Installation
+------------
+
+You can install TweetNaCl.js via a package manager:
+
+[Bower](http://bower.io):
+
+ $ bower install tweetnacl
+
+[NPM](https://www.npmjs.org/):
+
+ $ npm install tweetnacl
+
+or [download source code](https://github.com/dchest/tweetnacl-js/releases).
+
+
+Usage
+------
+
+All API functions accept and return bytes as `Uint8Array`s. If you need to
+encode or decode strings, use functions from `nacl.util` namespace.
+
+### Public-key authenticated encryption (box)
+
+Implements *curve25519-xsalsa20-poly1305*.
+
+#### nacl.box.keyPair()
+
+Generates a new random key pair for box and returns it as an object with
+`publicKey` and `secretKey` members:
+
+ {
+ publicKey: ..., // Uint8Array with 32-byte public key
+ secretKey: ... // Uint8Array with 32-byte secret key
+ }
+
+
+#### nacl.box.keyPair.fromSecretKey(secretKey)
+
+Returns a key pair for box with public key corresponding to the given secret
+key.
+
+#### nacl.box(message, nonce, theirPublicKey, mySecretKey)
+
+Encrypt 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
+`nacl.box.overheadLength` longer than the original message.
+
+#### nacl.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 `false` if authentication fails.
+
+#### nacl.box.before(theirPublicKey, mySecretKey)
+
+Returns a precomputed shared key which can be used in `nacl.box.after` and
+`nacl.box.open.after`.
+
+#### nacl.box.after(message, nonce, sharedKey)
+
+Same as `nacl.box`, but uses a shared key precomputed with `nacl.box.before`.
+
+#### nacl.box.open.after(box, nonce, sharedKey)
+
+Same as `nacl.box.open`, but uses a shared key precomputed with `nacl.box.before`.
+
+#### nacl.box.publicKeyLength = 32
+
+Length of public key in bytes.
+
+#### nacl.box.secretKeyLength = 32
+
+Length of secret key in bytes.
+
+#### nacl.box.sharedKeyLength = 32
+
+Length of precomputed shared key in bytes.
+
+#### nacl.box.nonceLength = 24
+
+Length of nonce in bytes.
+
+#### nacl.box.overheadLength = 16
+
+Length of overhead added to box compared to original message.
+
+
+### Secret-key authenticated encryption (secretbox)
+
+Implements *xsalsa20-poly1305*.
+
+#### nacl.secretbox(message, nonce, key)
+
+Encrypt 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
+`nacl.secretbox.overheadLength` longer than the original message.
+
+#### nacl.secretbox.open(box, nonce, key)
+
+Authenticates and decrypts the given secret box using the key and the nonce.
+
+Returns the original message, or `false` if authentication fails.
+
+#### nacl.secretbox.keyLength = 32
+
+Length of key in bytes.
+
+#### nacl.secretbox.nonceLength = 24
+
+Length of nonce in bytes.
+
+#### nacl.secretbox.overheadLength = 16
+
+Length of overhead added to secret box compared to original message.
+
+
+### Scalar multiplication
+
+Implements *curve25519*.
+
+#### nacl.scalarMult(n, p)
+
+Multiplies an integer `n` by a group element `p` and returns the resulting
+group element.
+
+#### nacl.scalarMult.base(n)
+
+Multiplies an integer `n` by a standard group element and returns the resulting
+group element.
+
+#### nacl.scalarMult.scalarLength = 32
+
+Length of scalar in bytes.
+
+#### nacl.scalarMult.groupElementLength = 32
+
+Length of group element in bytes.
+
+
+### Signatures
+
+Implements [ed25519](http://ed25519.cr.yp.to).
+
+#### nacl.sign.keyPair()
+
+Generates new random key pair for signing and returns it as an object with
+`publicKey` and `secretKey` members:
+
+ {
+ publicKey: ..., // Uint8Array with 32-byte public key
+ secretKey: ... // Uint8Array with 64-byte secret key
+ }
+
+#### nacl.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
+`nacl.sign.keyPair` or `nacl.sign.keyPair.fromSeed`.
+
+#### nacl.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 `nacl.sign.keyPair` to generate a new
+key pair from a random seed.
+
+#### nacl.sign(message, secretKey)
+
+Signs the message using the secret key and returns a signed message.
+
+#### nacl.sign.open(signedMessage, publicKey)
+
+Verifies the signed message and returns the message without signature.
+
+Returns `null` if verification failed.
+
+#### nacl.sign.detached(message, secretKey)
+
+Signs the message using the secret key and returns a signature.
+
+#### nacl.sign.detached.verify(message, signature, publicKey)
+
+Verifies the signature for the message and returns `true` if verification
+succeeded or `false` if it failed.
+
+#### nacl.sign.publicKeyLength = 32
+
+Length of signing public key in bytes.
+
+#### nacl.sign.secretKeyLength = 64
+
+Length of signing secret key in bytes.
+
+#### nacl.sign.seedLength = 32
+
+Length of seed for `nacl.sign.keyPair.fromSeed` in bytes.
+
+#### nacl.sign.signatureLength = 64
+
+Length of signature in bytes.
+
+
+### Hashing
+
+Implements *SHA-512*.
+
+#### nacl.hash(message)
+
+Returns SHA-512 hash of the message.
+
+#### nacl.hash.hashLength = 64
+
+Length of hash in bytes.
+
+
+### Random bytes generation
+
+#### nacl.randomBytes(length)
+
+Returns a `Uint8Array` 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)
+
+Note that browsers are required to throw `QuotaExceededError` exception if
+requested `length` is more than 65536, so do not ask for more than 65536 bytes
+in *one call* (multiple calls to get as many bytes as you like are okay:
+browsers can generate infinite amount of random bytes without any bad
+consequences).
+
+If the platform doesn't provide a suitable PRNG, the following functions,
+which require random numbers, will throw exception:
+
+* `nacl.randomBytes`
+* `nacl.box.keyPair`
+* `nacl.sign.keyPair`
+
+Other functions are deterministic and will continue working.
+
+If a platform you are targeting doesn't implement secure random number
+generator, but you somehow have a cryptographically-strong source of entropy
+(not `Math.random`!), and you know what you are doing, you can plug it into
+TweetNaCl.js like this:
+
+ nacl.setPRNG(function(x, n) {
+ // ... copy n random bytes into x ...
+ });
+
+Note that `nacl.setPRNG` *completely replaces* internal random byte generator
+with the one provided.
+
+
+### Constant-time comparison
+
+#### nacl.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.
+
+
+### Utilities
+
+Encoding/decoding functions are provided for convenience. They are correct,
+however their performance and wide compatibility with uncommon runtimes is not
+something that is considered important compared to the simplicity and size of
+implementation. You can use third-party libraries if you need to.
+
+#### nacl.util.decodeUTF8(string)
+
+Decodes string and returns `Uint8Array` of bytes.
+
+#### nacl.util.encodeUTF8(array)
+
+Encodes `Uint8Array` or `Array` of bytes into string.
+
+#### nacl.util.decodeBase64(string)
+
+Decodes Base-64 encoded string and returns `Uint8Array` of bytes.
+
+#### nacl.util.encodeBase64(array)
+
+Encodes `Uint8Array` or `Array` of bytes into string using Base-64 encoding.
+
+
+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 (we test on 0.10 and later)
+
+
+Development and testing
+------------------------
+
+Install NPM modules needed for development:
+
+ $ npm install
+
+To build minified versions:
+
+ $ npm run build
+
+Tests use minified version, so make sure to rebuild it every time you change
+`nacl.js` or `nacl-fast.js`.
+
+### Testing
+
+To run tests in Node.js:
+
+ $ npm test
+
+By default all tests described here work on `nacl.min.js`. To test other
+versions, set environment variable `NACL_SRC` to the file name you want to test.
+For example, the following command will test fast minified version:
+
+ $ NACL_SRC=nacl-fast.min.js npm test
+
+To run full suite of tests in Node.js, including comparing outputs of
+JavaScript port to outputs of the original C version:
+
+ $ npm run testall
+
+To prepare tests for browsers:
+
+ $ npm run browser
+
+and then open `test/browser/test.html` (or `test/browser/test-fast.html`) to
+run them.
+
+To run headless browser tests with `testling`:
+
+ $ npm run testling
+
+(If you get `Error: spawn ENOENT`, install *xvfb*: `sudo apt-get install xvfb`.)
+
+### Benchmarking
+
+To run benchmarks in Node.js:
+
+ $ npm run bench
+ $ NACL_SRC=nacl-fast.min.js npm run bench
+
+To run benchmarks in a browser, open `test/benchmark/bench.html` (or
+`test/benchmark/bench-fast.html`).
+
+
+Contributors
+------------
+
+JavaScript port:
+
+ * [Dmitry Chestnykh](http://github.com/dchest) (ported xsalsa20, poly1305, curve25519)
+ * [Devi Mandiri](https://github.com/devi) (ported curve25519, ed25519, sha512)
+
+Original authors of [NaCl](http://nacl.cr.yp.to), [TweetNaCl](http://tweetnacl.cr.yp.to)
+and [Poly1305-donna](https://github.com/floodyberry/poly1305-donna)
+(who are *not* responsible for any errors in this implementation):
+
+ * [Daniel J. Bernstein](http://cr.yp.to/djb.html)
+ * Wesley Janssen
+ * [Tanja Lange](http://hyperelliptic.org/tanja)
+ * [Peter Schwabe](http://www.cryptojedi.org/users/peter/)
+ * [Matthew Dempsky](https://github.com/mdempsky)
+ * [Andrew Moon](https://github.com/floodyberry)
+
+Contributors have dedicated their work to the public domain.
+
+This software is distributed without any warranty.
+
+
+Third-party libraries based on TweetNaCl.js
+-------------------------------------------
+
+* [forward-secrecy](https://github.com/alax/forward-secrecy) — Axolotl ratchet implementation
+* [nacl-stream](https://github.com/dchest/nacl-stream-js) - streaming encryption
+* [tweetnacl-auth-js](https://github.com/dchest/tweetnacl-auth-js) — implementation of [`crypto_auth`](http://nacl.cr.yp.to/auth.html)
+
+
+Who uses it
+-----------
+
+Some notable users of TweetNaCl.js:
+
+* [miniLock](http://minilock.io/)
+* [Stellar](https://www.stellar.org/)
Code Review / simantics / district.git / blobdiff