sodium-javascript/crypto_secretbox.js

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JavaScript
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2020-05-04 19:04:41 +00:00
var { crypto_stream, crypto_stream_xor } = require('./crypto_stream')
var { crypto_onetimeauth, crypto_onetimeauth_verify } = require('./crypto_onetimeauth')
var crypto_secretbox_KEYBYTES = 32,
crypto_secretbox_NONCEBYTES = 24,
crypto_secretbox_ZEROBYTES = 32,
crypto_secretbox_BOXZEROBYTES = 16,
crypto_secretbox_MACBYTES = 16
module.exports = {
crypto_secretbox,
crypto_secretbox_open,
crypto_secretbox_detached,
crypto_secretbox_open_detached,
crypto_secretbox_easy,
crypto_secretbox_open_easy,
crypto_secretbox_KEYBYTES,
crypto_secretbox_NONCEBYTES,
crypto_secretbox_ZEROBYTES,
crypto_secretbox_BOXZEROBYTES,
crypto_secretbox_MACBYTES
}
function crypto_secretbox(c,m,d,n,k) {
var i;
if (d < 32) return -1;
crypto_stream_xor(c,0,m,0,d,n,k);
crypto_onetimeauth(c, 16, c, 32, d - 32, c);
for (i = 0; i < 16; i++) c[i] = 0;
return 0;
}
function crypto_secretbox_open(m,c,d,n,k) {
var i;
var x = new Uint8Array(32);
if (d < 32) return -1;
crypto_stream(x,0,32,n,k);
if (crypto_onetimeauth_verify(c, 16,c, 32,d - 32,x) !== 0) return -1;
crypto_stream_xor(m,0,c,0,d,n,k);
for (i = 0; i < 32; i++) m[i] = 0;
return 0;
}
function crypto_secretbox_detached (o, mac, msg, n, k) {
check(mac, crypto_secretbox_MACBYTES)
var tmp = new Uint8Array(msg.length + mac.length)
crypto_secretbox_easy(tmp, msg, n, k)
o.set(tmp.subarray(0, msg.length))
mac.set(tmp.subarray(msg.length))
}
function crypto_secretbox_open_detached (msg, o, mac, n, k) {
check(mac, crypto_secretbox_MACBYTES)
var tmp = new Uint8Array(o.length + mac.length)
tmp.set(o)
tmp.set(mac, msg.length)
return crypto_secretbox_open_easy(msg, tmp, n, k)
}
function crypto_secretbox_easy(o, msg, n, k) {
check(msg, 0)
check(o, msg.length + crypto_secretbox_MACBYTES)
check(n, crypto_secretbox_NONCEBYTES)
check(k, crypto_secretbox_KEYBYTES)
var i
var m = new Uint8Array(crypto_secretbox_ZEROBYTES + msg.length);
var c = new Uint8Array(m.length);
for (i = 0; i < msg.length; i++) m[i+crypto_secretbox_ZEROBYTES] = msg[i];
crypto_secretbox(c, m, m.length, n, k);
for (i = crypto_secretbox_BOXZEROBYTES; i < c.length; i++) o[i - crypto_secretbox_BOXZEROBYTES] = c[i]
}
function crypto_secretbox_open_easy(msg, box, n, k) {
check(box, crypto_secretbox_MACBYTES)
check(msg, box.length - crypto_secretbox_MACBYTES)
check(n, crypto_secretbox_NONCEBYTES)
check(k, crypto_secretbox_KEYBYTES)
var i
var c = new Uint8Array(crypto_secretbox_BOXZEROBYTES + box.length);
var m = new Uint8Array(c.length);
for (i = 0; i < box.length; i++) c[i+crypto_secretbox_BOXZEROBYTES] = box[i];
if (c.length < 32) return false;
if (crypto_secretbox_open(m, c, c.length, n, k) !== 0) return false;
for (i = crypto_secretbox_ZEROBYTES; i < m.length; i++) msg[i - crypto_secretbox_ZEROBYTES] = m[i]
return true
}
function check (buf, len) {
if (!buf || (len && buf.length < len)) throw new Error('Argument must be a buffer' + (len ? ' of length ' + len : ''))
}