SHA256
jhkaktus
2ff58441f4
Adds a vanilla ES-module crypto layer for the browser: - Argon2id (t=2, m=16 MiB, p=1) derives a 256-bit session key from the passphrase; the passphrase never leaves the client. - Records are encrypted with XChaCha20-Poly1305, fresh 24-byte nonce per record, per-record salt bound into the AEAD associated data together with the uuid (tamper/swap detection). - Vendored audited @noble/hashes + @noble/ciphers ES modules; verified end-to-end in node (encrypt/decrypt roundtrip, wrong key, tampered salt, swapped uuid all rejected). 🤖 Generated with Codebuff Co-Authored-By: Codebuff <noreply@codebuff.com>
461 lines
18 KiB
JavaScript
461 lines
18 KiB
JavaScript
/**
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* ChaCha stream cipher, released
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* in 2008. Developed after Salsa20, ChaCha aims to increase diffusion per round.
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* It was standardized in
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* {@link https://www.rfc-editor.org/rfc/rfc8439 | RFC 8439} and
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* is now used in TLS 1.3.
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*
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* {@link https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-xchacha | XChaCha20}
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* extended-nonce variant is also provided. Similar to XSalsa, it's safe to use with
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* randomly-generated nonces.
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*
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* Check out
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* {@link http://cr.yp.to/chacha/chacha-20080128.pdf | PDF},
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* {@link https://en.wikipedia.org/wiki/Salsa20 | wiki}, and
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* {@link https://cr.yp.to/chacha.html | website}.
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*
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* @module
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*/
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import { createCipher, createPRG, rotl } from "./_arx.js";
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import { poly1305 } from "./_poly1305.js";
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import { abytes, clean, equalBytes, getOutput, isLE, swap32IfBE, u64Lengths, wrapCipher, } from "./utils.js";
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/**
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* ChaCha core function. Uses an unrolled loop (chachaCore, hchacha) - 4x
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* faster than a simple loop, but larger & harder to read. A simple-loop
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* reference version lives in `test/misc/micro-ciphers.ts`;
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* `test/arx.test.ts` keeps the two aligned.
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* The specific implementation is selected in `createCipher` below.
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*/
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/** RFC 8439 §2.3 block core for `state = constants | key | counter | nonce`. */
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// prettier-ignore
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function chachaCore(s, k, n, out, cnt, rounds = 20) {
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let y00 = s[0], y01 = s[1], y02 = s[2], y03 = s[3], // "expa" "nd 3" "2-by" "te k"
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y04 = k[0], y05 = k[1], y06 = k[2], y07 = k[3], // Key Key Key Key
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y08 = k[4], y09 = k[5], y10 = k[6], y11 = k[7], // Key Key Key Key
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y12 = cnt, y13 = n[0], y14 = n[1], y15 = n[2]; // Counter Nonce Nonce Nonce
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// Save state to temporary variables
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let x00 = y00, x01 = y01, x02 = y02, x03 = y03, x04 = y04, x05 = y05, x06 = y06, x07 = y07, x08 = y08, x09 = y09, x10 = y10, x11 = y11, x12 = y12, x13 = y13, x14 = y14, x15 = y15;
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for (let r = 0; r < rounds; r += 2) {
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x00 = (x00 + x04) | 0;
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x12 = rotl(x12 ^ x00, 16);
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x08 = (x08 + x12) | 0;
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x04 = rotl(x04 ^ x08, 12);
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x00 = (x00 + x04) | 0;
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x12 = rotl(x12 ^ x00, 8);
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x08 = (x08 + x12) | 0;
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x04 = rotl(x04 ^ x08, 7);
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x01 = (x01 + x05) | 0;
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x13 = rotl(x13 ^ x01, 16);
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x09 = (x09 + x13) | 0;
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x05 = rotl(x05 ^ x09, 12);
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x01 = (x01 + x05) | 0;
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x13 = rotl(x13 ^ x01, 8);
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x09 = (x09 + x13) | 0;
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x05 = rotl(x05 ^ x09, 7);
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x02 = (x02 + x06) | 0;
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x14 = rotl(x14 ^ x02, 16);
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x10 = (x10 + x14) | 0;
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x06 = rotl(x06 ^ x10, 12);
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x02 = (x02 + x06) | 0;
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x14 = rotl(x14 ^ x02, 8);
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x10 = (x10 + x14) | 0;
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x06 = rotl(x06 ^ x10, 7);
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x03 = (x03 + x07) | 0;
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x15 = rotl(x15 ^ x03, 16);
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x11 = (x11 + x15) | 0;
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x07 = rotl(x07 ^ x11, 12);
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x03 = (x03 + x07) | 0;
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x15 = rotl(x15 ^ x03, 8);
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x11 = (x11 + x15) | 0;
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x07 = rotl(x07 ^ x11, 7);
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x00 = (x00 + x05) | 0;
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x15 = rotl(x15 ^ x00, 16);
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x10 = (x10 + x15) | 0;
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x05 = rotl(x05 ^ x10, 12);
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x00 = (x00 + x05) | 0;
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x15 = rotl(x15 ^ x00, 8);
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x10 = (x10 + x15) | 0;
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x05 = rotl(x05 ^ x10, 7);
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x01 = (x01 + x06) | 0;
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x12 = rotl(x12 ^ x01, 16);
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x11 = (x11 + x12) | 0;
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x06 = rotl(x06 ^ x11, 12);
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x01 = (x01 + x06) | 0;
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x12 = rotl(x12 ^ x01, 8);
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x11 = (x11 + x12) | 0;
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x06 = rotl(x06 ^ x11, 7);
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x02 = (x02 + x07) | 0;
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x13 = rotl(x13 ^ x02, 16);
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x08 = (x08 + x13) | 0;
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x07 = rotl(x07 ^ x08, 12);
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x02 = (x02 + x07) | 0;
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x13 = rotl(x13 ^ x02, 8);
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x08 = (x08 + x13) | 0;
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x07 = rotl(x07 ^ x08, 7);
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x03 = (x03 + x04) | 0;
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x14 = rotl(x14 ^ x03, 16);
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x09 = (x09 + x14) | 0;
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x04 = rotl(x04 ^ x09, 12);
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x03 = (x03 + x04) | 0;
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x14 = rotl(x14 ^ x03, 8);
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x09 = (x09 + x14) | 0;
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x04 = rotl(x04 ^ x09, 7);
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}
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// RFC 8439 §2.3 / §2.3.1: add the original state words back in state order.
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let oi = 0;
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out[oi++] = (y00 + x00) | 0;
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out[oi++] = (y01 + x01) | 0;
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out[oi++] = (y02 + x02) | 0;
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out[oi++] = (y03 + x03) | 0;
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out[oi++] = (y04 + x04) | 0;
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out[oi++] = (y05 + x05) | 0;
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out[oi++] = (y06 + x06) | 0;
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out[oi++] = (y07 + x07) | 0;
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out[oi++] = (y08 + x08) | 0;
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out[oi++] = (y09 + x09) | 0;
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out[oi++] = (y10 + x10) | 0;
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out[oi++] = (y11 + x11) | 0;
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out[oi++] = (y12 + x12) | 0;
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out[oi++] = (y13 + x13) | 0;
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out[oi++] = (y14 + x14) | 0;
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out[oi++] = (y15 + x15) | 0;
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}
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/**
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* hchacha hashes key and nonce into key' and nonce' for xchacha20.
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* Algorithmically identical to `hchacha_small` from `test/misc/micro-ciphers.ts`,
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* but this exported path normalizes word order on big-endian hosts.
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* Reuses `chachaCore` and subtracts its feed-forward, keeping the hot per-block
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* path untouched.
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* @param s - Sigma constants as 32-bit words.
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* @param k - Key words.
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* @param i - Nonce-prefix words.
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* @param out - Output buffer for the derived subkey.
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* @example
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* Derives the XChaCha subkey from sigma, key, and nonce-prefix words.
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*
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* ```ts
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* const sigma = new Uint32Array(4);
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* const key = new Uint32Array(8);
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* const nonce = new Uint32Array(4);
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* const out = new Uint32Array(8);
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* hchacha(sigma, key, nonce, out);
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* ```
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*/
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// prettier-ignore
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export function hchacha(s, k, i, out) {
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// Runs the shared chachaCore permutation, then subtracts the RFC 8439 feed-forward
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// it applies, recovering the raw permutation words hchacha needs.
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// LE hosts read the caller arrays in place (no copies); BE hosts get
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// byte-swapped scratch copies, wiped before returning.
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const s2 = isLE ? s : swap32IfBE(s.slice(0, 4));
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const k2 = isLE ? k : swap32IfBE(k.slice(0, 8));
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const i2 = isLE ? i : swap32IfBE(i.slice(0, 4));
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const t = new Uint32Array(16);
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chachaCore(s2, k2, i2.subarray(1), t, i2[0]);
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let oi = 0;
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out[oi++] = (t[0] - s2[0]) | 0;
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out[oi++] = (t[1] - s2[1]) | 0;
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out[oi++] = (t[2] - s2[2]) | 0;
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out[oi++] = (t[3] - s2[3]) | 0;
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out[oi++] = (t[12] - i2[0]) | 0;
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out[oi++] = (t[13] - i2[1]) | 0;
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out[oi++] = (t[14] - i2[2]) | 0;
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out[oi++] = (t[15] - i2[3]) | 0;
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swap32IfBE(out);
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if (!isLE)
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clean(s2, k2, i2);
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clean(t);
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}
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/**
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* Original, non-RFC chacha20 from DJB. 8-byte nonce, 8-byte counter.
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* The nonce/counter layout still reserves 8 counter bytes internally, but the shared public
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* `counter` argument follows noble's strict non-wrapping 32-bit policy. See `src/_arx.ts`
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* near `MAX_COUNTER` for the full counter-policy rationale.
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* @param key - 16-byte or 32-byte key.
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* @param nonce - 8-byte nonce.
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* @param data - Input bytes to xor with the keystream.
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* @param output - Optional destination buffer.
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* @param counter - Initial block counter.
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* @returns Encrypted or decrypted bytes.
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* @example
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* Encrypts bytes with the original 8-byte-nonce ChaCha variant and a fresh key/nonce.
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*
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* ```ts
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* import { chacha20orig } from '@noble/ciphers/chacha.js';
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* import { randomBytes } from '@noble/ciphers/utils.js';
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* const key = randomBytes(32);
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* const nonce = randomBytes(8);
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* chacha20orig(key, nonce, new Uint8Array(4));
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* ```
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*/
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export const chacha20orig = /* @__PURE__ */ createCipher(chachaCore, {
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counterRight: false,
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counterLength: 8,
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allowShortKeys: true,
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});
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/**
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* ChaCha stream cipher. Conforms to RFC 8439 (IETF, TLS). 12-byte nonce, 4-byte counter.
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* With smaller nonce, it's not safe to make it random (CSPRNG), due to collision chance.
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* @param key - 32-byte key.
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* @param nonce - 12-byte nonce.
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* @param data - Input bytes to xor with the keystream.
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* @param output - Optional destination buffer.
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* @param counter - Initial block counter.
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* @returns Encrypted or decrypted bytes.
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* @example
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* Encrypts bytes with the RFC 8439 ChaCha20 stream cipher and a fresh key/nonce.
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*
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* ```ts
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* import { chacha20 } from '@noble/ciphers/chacha.js';
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* import { randomBytes } from '@noble/ciphers/utils.js';
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* const key = randomBytes(32);
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* const nonce = randomBytes(12);
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* chacha20(key, nonce, new Uint8Array(4));
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* ```
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*/
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export const chacha20 = /* @__PURE__ */ createCipher(chachaCore, {
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counterRight: false,
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counterLength: 4,
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allowShortKeys: false,
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});
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/**
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* XChaCha eXtended-nonce ChaCha. With 24-byte nonce, it's safe to make it random (CSPRNG).
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* See {@link https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-xchacha | the IRTF draft}.
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* The nonce/counter layout still reserves 8 counter bytes internally, but the shared public
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* `counter` argument follows noble's strict non-wrapping 32-bit policy. See `src/_arx.ts`
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* near `MAX_COUNTER` for the full counter-policy rationale.
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* @param key - 32-byte key.
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* @param nonce - 24-byte extended nonce.
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* @param data - Input bytes to xor with the keystream.
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* @param output - Optional destination buffer.
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* @param counter - Initial block counter.
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* @returns Encrypted or decrypted bytes.
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* @example
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* Encrypts bytes with XChaCha20 using a fresh key and random 24-byte nonce.
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*
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* ```ts
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* import { xchacha20 } from '@noble/ciphers/chacha.js';
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* import { randomBytes } from '@noble/ciphers/utils.js';
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* const key = randomBytes(32);
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* const nonce = randomBytes(24);
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* xchacha20(key, nonce, new Uint8Array(4));
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* ```
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*/
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export const xchacha20 = /* @__PURE__ */ createCipher(chachaCore, {
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counterRight: false,
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counterLength: 8,
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extendNonceFn: hchacha,
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allowShortKeys: false,
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});
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/**
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* Reduced 8-round chacha, described in original paper.
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* @param key - 32-byte key.
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* @param nonce - 12-byte nonce.
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* @param data - Input bytes to xor with the keystream.
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* @param output - Optional destination buffer.
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* @param counter - Initial block counter.
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* @returns Encrypted or decrypted bytes.
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* @example
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* Uses the reduced 8-round variant for non-critical workloads with a fresh key/nonce.
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*
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* ```ts
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* import { chacha8 } from '@noble/ciphers/chacha.js';
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* import { randomBytes } from '@noble/ciphers/utils.js';
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* const key = randomBytes(32);
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* const nonce = randomBytes(12);
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* chacha8(key, nonce, new Uint8Array(4));
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* ```
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*/
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export const chacha8 = /* @__PURE__ */ createCipher(chachaCore, {
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counterRight: false,
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counterLength: 4,
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rounds: 8,
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});
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/**
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* Reduced 12-round chacha, described in original paper.
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* @param key - 32-byte key.
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* @param nonce - 12-byte nonce.
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* @param data - Input bytes to xor with the keystream.
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* @param output - Optional destination buffer.
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* @param counter - Initial block counter.
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* @returns Encrypted or decrypted bytes.
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* @example
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* Uses the reduced 12-round variant for non-critical workloads with a fresh key/nonce.
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*
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* ```ts
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* import { chacha12 } from '@noble/ciphers/chacha.js';
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* import { randomBytes } from '@noble/ciphers/utils.js';
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* const key = randomBytes(32);
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* const nonce = randomBytes(12);
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* chacha12(key, nonce, new Uint8Array(4));
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* ```
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*/
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export const chacha12 = /* @__PURE__ */ createCipher(chachaCore, {
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counterRight: false,
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counterLength: 4,
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rounds: 12,
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});
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// Test-only hook: exposes the unrolled production core so tests can compare it
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// with the simple/reference core from `test/misc/micro-ciphers.ts`.
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export const __TESTS = /* @__PURE__ */ Object.freeze({ chachaCore });
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// RFC 8439 §2.8.1 pad16(x): shared zero block for AAD/ciphertext padding.
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const ZEROS16 = /* @__PURE__ */ new Uint8Array(16);
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// RFC 8439 §2.8 / §2.8.1: aligned inputs add nothing, otherwise append 16-(len%16) zero bytes.
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const updatePadded = (h, msg) => {
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h.update(msg);
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const leftover = msg.length % 16;
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if (leftover)
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h.update(ZEROS16.subarray(leftover));
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};
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// RFC 8439 §2.6.1 poly1305_key_gen returns `block[0..31]`, so AEAD key
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// generation only needs 32 zero bytes.
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const ZEROS32 = /* @__PURE__ */ new Uint8Array(32);
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function computeTag(fn, key, nonce, ciphertext, AAD) {
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if (AAD !== undefined)
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abytes(AAD, undefined, 'AAD');
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// RFC 8439 §2.6 / §2.8: derive the Poly1305 one-time key from counter 0,
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// then MAC AAD || pad16(AAD) || ciphertext || pad16(ciphertext) || len(AAD) || len(ciphertext).
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const authKey = fn(key, nonce, ZEROS32);
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const lengths = u64Lengths(ciphertext.length, AAD ? AAD.length : 0, true);
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// Methods below can be replaced with
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// `return poly1305_computeTag_small(authKey, lengths, ciphertext, AAD)`
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// from `test/misc/micro-ciphers.ts`.
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const h = poly1305.create(authKey);
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if (AAD)
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updatePadded(h, AAD);
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updatePadded(h, ciphertext);
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h.update(lengths);
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const res = h.digest();
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clean(authKey, lengths);
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return res;
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}
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/**
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* AEAD algorithm from RFC 8439.
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* Salsa20 and chacha (RFC 8439) use poly1305 differently.
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* We could have composed them, but it's hard because of authKey:
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* In salsa20, authKey changes position in salsa stream.
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* In chacha, authKey can't be computed inside computeTag, it modifies the counter.
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*/
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export const _poly1305_aead = (xorStream) => (key, nonce, AAD) => {
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// This borrows caller key/nonce/AAD buffers by reference; mutating them after construction
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// changes future encrypt/decrypt results.
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const tagLength = 16;
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return {
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encrypt(plaintext, output) {
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const plength = plaintext.length;
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output = getOutput(plength + tagLength, output, false);
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output.set(plaintext);
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const oPlain = output.subarray(0, -tagLength);
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// RFC 8439 §2.8: payload encryption starts at counter 1 because counter 0 produced the OTK.
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xorStream(key, nonce, oPlain, oPlain, 1);
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const tag = computeTag(xorStream, key, nonce, oPlain, AAD);
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output.set(tag, plength); // append tag
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clean(tag);
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return output;
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},
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decrypt(ciphertext, output) {
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output = getOutput(ciphertext.length - tagLength, output, false);
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const data = ciphertext.subarray(0, -tagLength);
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const passedTag = ciphertext.subarray(-tagLength);
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const tag = computeTag(xorStream, key, nonce, data, AAD);
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// RFC 8439 §2.8 / §4: authenticate ciphertext before decrypting it, and compare tags with
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// the constant-time equalBytes() helper rather than decrypting speculative plaintext first.
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if (!equalBytes(passedTag, tag)) {
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clean(tag);
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throw new Error('invalid tag');
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}
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output.set(ciphertext.subarray(0, -tagLength));
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// Actual decryption
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xorStream(key, nonce, output, output, 1); // start stream with i=1
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clean(tag);
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return output;
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},
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};
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};
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/**
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* ChaCha20-Poly1305 from RFC 8439.
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*
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* Unsafe to use random nonces under the same key, due to collision chance.
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* Prefer XChaCha instead.
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* @param key - 32-byte key.
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* @param nonce - 12-byte nonce.
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* @param AAD - Additional authenticated data.
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* @returns AEAD cipher instance.
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* @example
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* Encrypts and authenticates plaintext with a fresh key and nonce.
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*
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* ```ts
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* import { chacha20poly1305 } from '@noble/ciphers/chacha.js';
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* import { randomBytes } from '@noble/ciphers/utils.js';
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* const key = randomBytes(32);
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* const nonce = randomBytes(12);
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* const aad = new TextEncoder().encode('session metadata');
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* const cipher = chacha20poly1305(key, nonce, aad);
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* cipher.encrypt(new Uint8Array([1, 2, 3]));
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* ```
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*/
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export const chacha20poly1305 = /* @__PURE__ */ wrapCipher({ blockSize: 64, nonceLength: 12, tagLength: 16, withAAD: true },
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/* @__PURE__ */ _poly1305_aead(chacha20));
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/**
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* XChaCha20-Poly1305 extended-nonce chacha.
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*
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* Can be safely used with random nonces (CSPRNG).
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* See {@link https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-xchacha | the IRTF draft}.
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* @param key - 32-byte key.
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* @param nonce - 24-byte nonce.
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* @param AAD - Additional authenticated data.
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* @returns AEAD cipher instance.
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* @example
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* Encrypts and authenticates plaintext with a fresh key and random 24-byte nonce.
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*
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* ```ts
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* import { xchacha20poly1305 } from '@noble/ciphers/chacha.js';
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* import { randomBytes } from '@noble/ciphers/utils.js';
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* const key = randomBytes(32);
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* const nonce = randomBytes(24);
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* const aad = new TextEncoder().encode('session metadata');
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* const cipher = xchacha20poly1305(key, nonce, aad);
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* cipher.encrypt(new Uint8Array([1, 2, 3]));
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* ```
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*/
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export const xchacha20poly1305 = /* @__PURE__ */ wrapCipher({ blockSize: 64, nonceLength: 24, tagLength: 16, withAAD: true },
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/* @__PURE__ */ _poly1305_aead(xchacha20));
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/**
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* Chacha20 CSPRNG (cryptographically secure pseudorandom number generator).
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* It's best to limit usage to non-production, non-critical cases: for example, test-only.
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* Compatible with libtomcrypt. It does not have a specification, so unclear how secure it is.
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* @param seed - Optional seed bytes mixed into the internal `key || nonce` state. When omitted,
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* only 32 random bytes are mixed into the 40-byte state.
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* @returns Seeded concrete `_XorStreamPRG` instance, including `clone()`.
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* @example
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* Seeds the test-only ChaCha20 DRBG from fresh entropy.
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*
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* ```ts
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* import { rngChacha20 } from '@noble/ciphers/chacha.js';
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* import { randomBytes } from '@noble/ciphers/utils.js';
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* const seed = randomBytes(32);
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* const prg = rngChacha20(seed);
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* prg.randomBytes(8);
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* ```
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*/
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export const rngChacha20 = /* @__PURE__ */ createPRG(chacha20orig, 64, 32, 8);
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/**
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* Chacha20/8 CSPRNG (cryptographically secure pseudorandom number generator).
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* It's best to limit usage to non-production, non-critical cases: for example, test-only.
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* Faster than `rngChacha20`.
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* @param seed - Optional seed bytes mixed into the internal `key || nonce` state. When omitted,
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* only 32 random bytes are mixed into the 44-byte state.
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* @returns Seeded concrete `_XorStreamPRG` instance, including `clone()`.
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* @example
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* Seeds the faster test-only ChaCha8 DRBG from fresh entropy.
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*
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* ```ts
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* import { rngChacha8 } from '@noble/ciphers/chacha.js';
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* import { randomBytes } from '@noble/ciphers/utils.js';
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* const seed = randomBytes(32);
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* const prg = rngChacha8(seed);
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* prg.randomBytes(8);
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* ```
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*/
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export const rngChacha8 = /* @__PURE__ */ createPRG(chacha8, 64, 32, 12);
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