sodium-javascript/crypto_box.js
Christophe Diederichs b44f83f0a8
Split library into modules (#20)
* crypto_stream: signature change needed to modularise

* move ed25519 arithmetic to separate module

* module: poly1305

* module: crypto_scalarmult

* module: crypto_hash

* module: crypto_sign

* module: crypto_secretbox

* move verify functions to crypto_verify module

* leftover crypto_stream functions

* module: crypto_onetimeauth

* module: crypto_box

* tidy up

* require ed25519.js

* update: crypto_hash

* add chacha20; align API with PR#21

* update sha512 to wasm module

* fix bugs in crypto_sign

* be standard

* add: crypto_box_seed_keypair; alias crypto_kx methods to crypto_box

* scalarmult: import curve methods; be standard

* correction: crypto_kx is not actually an alias of crypto_box

* export _9 constant field element

* add: crypto_box_seed_keypair

* removed duplicate module.exports declaraion

* declare constants about exports

* rename memzero -> sodium-memzero

* update sodium_memzero function to arr.fill(0)

* tidy: remove legacy functions

* added: crypto_aead_chacha20poly1305_ietf methods

* listen to linter

* add assertions

* chacha: readUint32Le generalised for uint8array; aead: standard fix

* add null check on ad param

* added: sodium_memcmp

* export sodium_memcmp

* export crypto_verify module

* sodium_memcmp returns boolean

* added: sodium_is_zero

* catch syntax error

* throw if crypto_aead cannot validate, fix typo in crypto_verify

* move chacha20 alg to external module

* use Uint8Arrays instead of buffers

* change checks to assertions

* bump to chacha 1.0.3 - remove Buffer dependency

* reduce code branching, align return values with sodium-native

* add sha-wasm deps to package.json

* standard fixes

* bump chacha20 to 1.0.4: remove Buffer dep

* move crypto_hash_sha256 to module to uncouple wasm dependencies

* add endian check: all other modules require members of this set

* correct filename: crypto_hash_sha256

* export constant: crypto_hash_sha512_BYTES
2020-06-18 17:09:03 +02:00

106 lines
3.2 KiB
JavaScript

const { crypto_hash_sha512 } = require('./crypto_hash')
const { crypto_scalarmult, crypto_scalarmult_base } = require('./crypto_scalarmult')
const { randombytes } = require('./randombytes')
const { crypto_generichash_batch } = require('./crypto_generichash')
const { crypto_secretbox_open_easy, crypto_secretbox_easy } = require('./crypto_secretbox')
const xsalsa20 = require('xsalsa20')
const assert = require('nanoassert')
var crypto_box_PUBLICKEYBYTES = 32,
crypto_box_SECRETKEYBYTES = 32,
crypto_box_BEFORENMBYTES = 32,
crypto_box_NONCEBYTES = 24,
crypto_box_ZEROBYTES = 32,
crypto_box_BOXZEROBYTES = 16,
crypto_box_SEALBYTES = 48,
crypto_box_SEEDBYTES = 32,
crypto_box_BEFORENMBYTES = 32
module.exports = {
crypto_box_keypair,
crypto_box_seed_keypair,
crypto_box_seal,
crypto_box_seal_open,
crypto_box_PUBLICKEYBYTES,
crypto_box_SECRETKEYBYTES,
crypto_box_BEFORENMBYTES,
crypto_box_NONCEBYTES,
crypto_box_ZEROBYTES,
crypto_box_BOXZEROBYTES,
crypto_box_SEALBYTES,
crypto_box_SEEDBYTES,
crypto_box_BEFORENMBYTES
}
function crypto_box_keypair(pk, sk) {
check(pk, crypto_box_PUBLICKEYBYTES)
check(sk, crypto_box_SECRETKEYBYTES)
randombytes(sk, 32)
return crypto_scalarmult_base(pk, sk)
}
function crypto_box_seed_keypair(pk, sk, seed) {
assert(pk.byteLength === crypto_box_PUBLICKEYBYTES, "pk should be 'crypto_box_PUBLICKEYBYTES' bytes")
assert(sk.byteLength === crypto_box_SECRETKEYBYTES, "sk should be 'crypto_box_SECRETKEYBYTES' bytes")
assert(sk.byteLength === crypto_box_SEEDBYTES, "sk should be 'crypto_box_SEEDBYTES' bytes")
const hash = new Uint8Array(64)
crypto_hash_sha512(hash, seed, 32)
sk.set(hash.subarray(0, 32))
hash.fill(0)
return crypto_scalarmult_base(pk, sk)
}
function crypto_box_seal(c, m, pk) {
check(c, crypto_box_SEALBYTES + m.length)
check(pk, crypto_box_PUBLICKEYBYTES)
var epk = c.subarray(0, crypto_box_PUBLICKEYBYTES)
var esk = new Uint8Array(crypto_box_SECRETKEYBYTES)
crypto_box_keypair(epk, esk)
var n = new Uint8Array(crypto_box_NONCEBYTES)
crypto_generichash_batch(n, [ epk, pk ])
var s = new Uint8Array(crypto_box_PUBLICKEYBYTES)
crypto_scalarmult(s, esk, pk)
var k = new Uint8Array(crypto_box_BEFORENMBYTES)
var zero = new Uint8Array(16)
xsalsa20.core_hsalsa20(k, zero, s, xsalsa20.SIGMA)
crypto_secretbox_easy(c.subarray(epk.length), m, n, k)
cleanup(esk)
}
function crypto_box_seal_open(m, c, pk, sk) {
check(c, crypto_box_SEALBYTES)
check(m, c.length - crypto_box_SEALBYTES)
check(pk, crypto_box_PUBLICKEYBYTES)
check(sk, crypto_box_SECRETKEYBYTES)
var epk = c.subarray(0, crypto_box_PUBLICKEYBYTES)
var n = new Uint8Array(crypto_box_NONCEBYTES)
crypto_generichash_batch(n, [ epk, pk ])
var s = new Uint8Array(crypto_box_PUBLICKEYBYTES)
crypto_scalarmult(s, sk, epk)
var k = new Uint8Array(crypto_box_BEFORENMBYTES)
var zero = new Uint8Array(16)
xsalsa20.core_hsalsa20(k, zero, s, xsalsa20.SIGMA)
return crypto_secretbox_open_easy(m, c.subarray(epk.length), n, k)
}
function check (buf, len) {
if (!buf || (len && buf.length < len)) throw new Error('Argument must be a buffer' + (len ? ' of length ' + len : ''))
}
function cleanup(arr) {
for (var i = 0; i < arr.length; i++) arr[i] = 0;
}