https://macgirvin.com/view/js/crypto.js?_v=5cad96cb434cf98424be2f121ca1b84f

1async function sodium_encrypt(element) {
2	if (typeof tinyMCE !== typeof undefined) {
3		tinyMCE.triggerSave(false,true);
4	}
5
6	let message = $(element).val();
7
8	if (!message) {
9		return false;
10	}
11
12	const password = prompt(aStr['passphrase']);
13
14	if (!password) {
15		return false;
16	}
17
18	const hint = bin2hex(prompt(aStr['passhint']));
19
20	const salt = crypto.getRandomValues(new Uint8Array(32)); // Generate a random salt (32 bytes)
21	const key = await derivePBKDF2Hash(password, salt);
22
23	const nonce = await sodium.randombytes_buf(sodium.crypto_secretbox_NONCEBYTES);
24
25	// Message can be a string, buffer, array, etc.
26	const ciphertext = await sodium.crypto_secretbox_easy(message, nonce, key);
27	delete message, password, key;
28
29	const payload = {
30		hint: hint,
31		alg: 'XSalsa20',
32		salt: await sodium.to_hex(salt),
33		nonce: await sodium.to_hex(nonce),
34		ciphertext: await sodium.to_hex(ciphertext)
35	};
36
37	const val = "[crypt]" + window.btoa(JSON.stringify(payload)) + '[/crypt]';
38
39	$(element).val(val);
40}
41
42async function sodium_decrypt(payload, element) {
43	let arr = JSON.parse(window.atob(payload));
44
45	if (arr.alg !== 'XSalsa20') {
46		alert('Unsupported algorithm');
47		return false;
48	}
49
50	let password = prompt((arr.hint.length) ? hex2bin(arr.hint) : aStr['passphrase']);
51
52	if (!password) {
53		return false;
54	}
55
56	const salt = await sodium.from_hex(arr.salt);
57	const nonce = await sodium.from_hex(arr.nonce);
58	const ciphertext = await sodium.from_hex(arr.ciphertext);
59
60
61	const key = await derivePBKDF2Hash(password, salt);
62
63	const decrypted = await sodium.crypto_secretbox_open_easy(ciphertext, nonce, key);
64	delete password, key;
65
66	if ($(element).css('display') === 'none' && typeof tinyMCE !== typeof undefined) {
67		tinyMCE.activeEditor.setContent(sodium.to_string(decrypted));
68	}
69	else {
70		$(element).html(sodium.to_string(decrypted));
71	}
72}
73
74async function derivePBKDF2Hash(password, salt) {
75	const encoder = new TextEncoder();
76	const passwordBuffer = encoder.encode(password);
77	const saltBuffer = encoder.encode(salt);
78
79	const key = await crypto.subtle.importKey(
80		'raw', // key format
81		passwordBuffer, // password as raw data
82		{ name: 'PBKDF2' }, // algorithm
83		false, // whether the key can be exported
84		['deriveBits'] // key usages
85	);
86
87	const derivedBits = await crypto.subtle.deriveBits(
88		{
89			name: 'PBKDF2',
90			salt: saltBuffer,
91			iterations: 100000, // The higher the more secure should be at least 100000
92			hash: 'SHA-256', // could also be SHA-512
93		},
94		key,
95		256 // derived key length in bits (32 bytes)
96	);
97
98	return new Uint8Array(derivedBits);
99}
100
101
102