sodium-javascript/crypto_scalarmult.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

78 lines
1.7 KiB
JavaScript

const { _9, _121665, gf, inv25519, pack25519, unpack25519, sel25519, A, M, Z, S } = require('./ed25519.js')
var crypto_scalarmult_BYTES = 32
var crypto_scalarmult_SCALARBYTES = 32
var crypto_scalarmult_BYTES = 32
var crypto_scalarmult_SCALARBYTES = 32
module.exports = {
crypto_scalarmult,
crypto_scalarmult_base,
crypto_scalarmult_BYTES,
crypto_scalarmult_SCALARBYTES
}
function crypto_scalarmult (q, n, p) {
check(q, crypto_scalarmult_BYTES)
check(n, crypto_scalarmult_SCALARBYTES)
check(p, crypto_scalarmult_BYTES)
var z = new Uint8Array(32)
var x = new Float64Array(80), r, i
var a = gf(), b = gf(), c = gf(),
d = gf(), e = gf(), f = gf()
for (i = 0; i < 31; i++) z[i] = n[i]
z[31] = (n[31] & 127) | 64
z[0] &= 248
unpack25519(x, p)
for (i = 0; i < 16; i++) {
b[i] = x[i]
d[i] = a[i] = c[i] = 0
}
a[0] = d[0] = 1
for (i = 254; i >= 0; --i) {
r = (z[i >>> 3] >>> (i & 7)) & 1
sel25519(a, b, r)
sel25519(c, d, r)
A(e, a, c)
Z(a, a, c)
A(c, b, d)
Z(b, b, d)
S(d, e)
S(f, a)
M(a, c, a)
M(c, b, e)
A(e, a, c)
Z(a, a, c)
S(b, a)
Z(c, d, f)
M(a, c, _121665)
A(a, a, d)
M(c, c, a)
M(a, d, f)
M(d, b, x)
S(b, e)
sel25519(a, b, r)
sel25519(c, d, r)
}
for (i = 0; i < 16; i++) {
x[i + 16] = a[i]
x[i + 32] = c[i]
x[i + 48] = b[i]
x[i + 64] = d[i]
}
var x32 = x.subarray(32)
var x16 = x.subarray(16)
inv25519(x32, x32)
M(x16, x16, x32)
pack25519(q, x16)
return 0
}
function crypto_scalarmult_base (q, n) {
return crypto_scalarmult(q, n, _9)
}
function check (buf, len) {
if (!buf || (len && buf.length < len)) throw new Error('Argument must be a buffer' + (len ? ' of length ' + len : ''))
}