/opt/canhelp/node_modules/@noble/ciphers
Edit: /opt/canhelp/node_modules/@noble/ciphers/chacha.js (14213B)
/**
* ChaCha stream cipher, released
* in 2008. Developed after Salsa20, ChaCha aims to increase diffusion per round.
* It was standardized in [RFC 8439](https://www.rfc-editor.org/rfc/rfc8439) and
* is now used in TLS 1.3.
*
* [XChaCha20](https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-xchacha)
* extended-nonce variant is also provided. Similar to XSalsa, it's safe to use with
* randomly-generated nonces.
*
* Check out [PDF](http://cr.yp.to/chacha/chacha-20080128.pdf) and
* [wiki](https://en.wikipedia.org/wiki/Salsa20) and
* [website](https://cr.yp.to/chacha.html).
*
* @module
*/
import { createCipher, createPRG, rotl } from "./_arx.js";
import { poly1305 } from "./_poly1305.js";
import { abytes, clean, equalBytes, getOutput, u64Lengths, wrapCipher, } from "./utils.js";
/**
* ChaCha core function. It is implemented twice:
* 1. Simple loop (chachaCore_small, hchacha_small)
* 2. Unrolled loop (chachaCore, hchacha) - 4x faster, but larger & harder to read
* The specific implementation is selected in `createCipher` below.
*/
/** quarter-round */
// prettier-ignore
function chachaQR(x, a, b, c, d) {
x[a] = (x[a] + x[b]) | 0;
x[d] = rotl(x[d] ^ x[a], 16);
x[c] = (x[c] + x[d]) | 0;
x[b] = rotl(x[b] ^ x[c], 12);
x[a] = (x[a] + x[b]) | 0;
x[d] = rotl(x[d] ^ x[a], 8);
x[c] = (x[c] + x[d]) | 0;
x[b] = rotl(x[b] ^ x[c], 7);
}
/** single round */
function chachaRound(x, rounds = 20) {
for (let r = 0; r < rounds; r += 2) {
chachaQR(x, 0, 4, 8, 12);
chachaQR(x, 1, 5, 9, 13);
chachaQR(x, 2, 6, 10, 14);
chachaQR(x, 3, 7, 11, 15);
chachaQR(x, 0, 5, 10, 15);
chachaQR(x, 1, 6, 11, 12);
chachaQR(x, 2, 7, 8, 13);
chachaQR(x, 3, 4, 9, 14);
}
}
const ctmp = /* @__PURE__ */ new Uint32Array(16);
/** Small version of chacha without loop unrolling. Unused, provided for auditability. */
// prettier-ignore
function chacha(s, k, i, out, isHChacha = true, rounds = 20) {
// Create initial array using common pattern
const y = Uint32Array.from([
s[0], s[1], s[2], s[3], // "expa" "nd 3" "2-by" "te k"
k[0], k[1], k[2], k[3], // Key Key Key Key
k[4], k[5], k[6], k[7], // Key Key Key Key
i[0], i[1], i[2], i[3], // Counter Counter Nonce Nonce
]);
const x = ctmp;
x.set(y);
chachaRound(x, rounds);
// hchacha extracts 8 specific bytes, chacha adds orig to result
if (isHChacha) {
const xindexes = [0, 1, 2, 3, 12, 13, 14, 15];
for (let i = 0; i < 8; i++)
out[i] = x[xindexes[i]];
}
else {
for (let i = 0; i < 16; i++)
out[i] = (y[i] + x[i]) | 0;
}
}
/** Identical to `chachaCore`. Unused. */
// @ts-ignore
const chachaCore_small = (s, k, n, out, cnt, rounds) => chacha(s, k, Uint32Array.from([n[0], n[1], cnt, 0]), out, false, rounds);
/** Identical to `hchacha`. Unused. */
// @ts-ignore
const hchacha_small = chacha;
/** Identical to `chachaCore_small`. Unused. */
// prettier-ignore
function chachaCore(s, k, n, out, cnt, rounds = 20) {
let y00 = s[0], y01 = s[1], y02 = s[2], y03 = s[3], // "expa" "nd 3" "2-by" "te k"
y04 = k[0], y05 = k[1], y06 = k[2], y07 = k[3], // Key Key Key Key
y08 = k[4], y09 = k[5], y10 = k[6], y11 = k[7], // Key Key Key Key
y12 = cnt, y13 = n[0], y14 = n[1], y15 = n[2]; // Counter Counter Nonce Nonce
// Save state to temporary variables
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;
for (let r = 0; r < rounds; r += 2) {
x00 = (x00 + x04) | 0;
x12 = rotl(x12 ^ x00, 16);
x08 = (x08 + x12) | 0;
x04 = rotl(x04 ^ x08, 12);
x00 = (x00 + x04) | 0;
x12 = rotl(x12 ^ x00, 8);
x08 = (x08 + x12) | 0;
x04 = rotl(x04 ^ x08, 7);
x01 = (x01 + x05) | 0;
x13 = rotl(x13 ^ x01, 16);
x09 = (x09 + x13) | 0;
x05 = rotl(x05 ^ x09, 12);
x01 = (x01 + x05) | 0;
x13 = rotl(x13 ^ x01, 8);
x09 = (x09 + x13) | 0;
x05 = rotl(x05 ^ x09, 7);
x02 = (x02 + x06) | 0;
x14 = rotl(x14 ^ x02, 16);
x10 = (x10 + x14) | 0;
x06 = rotl(x06 ^ x10, 12);
x02 = (x02 + x06) | 0;
x14 = rotl(x14 ^ x02, 8);
x10 = (x10 + x14) | 0;
x06 = rotl(x06 ^ x10, 7);
x03 = (x03 + x07) | 0;
x15 = rotl(x15 ^ x03, 16);
x11 = (x11 + x15) | 0;
x07 = rotl(x07 ^ x11, 12);
x03 = (x03 + x07) | 0;
x15 = rotl(x15 ^ x03, 8);
x11 = (x11 + x15) | 0;
x07 = rotl(x07 ^ x11, 7);
x00 = (x00 + x05) | 0;
x15 = rotl(x15 ^ x00, 16);
x10 = (x10 + x15) | 0;
x05 = rotl(x05 ^ x10, 12);
x00 = (x00 + x05) | 0;
x15 = rotl(x15 ^ x00, 8);
x10 = (x10 + x15) | 0;
x05 = rotl(x05 ^ x10, 7);
x01 = (x01 + x06) | 0;
x12 = rotl(x12 ^ x01, 16);
x11 = (x11 + x12) | 0;
x06 = rotl(x06 ^ x11, 12);
x01 = (x01 + x06) | 0;
x12 = rotl(x12 ^ x01, 8);
x11 = (x11 + x12) | 0;
x06 = rotl(x06 ^ x11, 7);
x02 = (x02 + x07) | 0;
x13 = rotl(x13 ^ x02, 16);
x08 = (x08 + x13) | 0;
x07 = rotl(x07 ^ x08, 12);
x02 = (x02 + x07) | 0;
x13 = rotl(x13 ^ x02, 8);
x08 = (x08 + x13) | 0;
x07 = rotl(x07 ^ x08, 7);
x03 = (x03 + x04) | 0;
x14 = rotl(x14 ^ x03, 16);
x09 = (x09 + x14) | 0;
x04 = rotl(x04 ^ x09, 12);
x03 = (x03 + x04) | 0;
x14 = rotl(x14 ^ x03, 8);
x09 = (x09 + x14) | 0;
x04 = rotl(x04 ^ x09, 7);
}
// Write output
let oi = 0;
out[oi++] = (y00 + x00) | 0;
out[oi++] = (y01 + x01) | 0;
out[oi++] = (y02 + x02) | 0;
out[oi++] = (y03 + x03) | 0;
out[oi++] = (y04 + x04) | 0;
out[oi++] = (y05 + x05) | 0;
out[oi++] = (y06 + x06) | 0;
out[oi++] = (y07 + x07) | 0;
out[oi++] = (y08 + x08) | 0;
out[oi++] = (y09 + x09) | 0;
out[oi++] = (y10 + x10) | 0;
out[oi++] = (y11 + x11) | 0;
out[oi++] = (y12 + x12) | 0;
out[oi++] = (y13 + x13) | 0;
out[oi++] = (y14 + x14) | 0;
out[oi++] = (y15 + x15) | 0;
}
/**
* hchacha hashes key and nonce into key' and nonce' for xchacha20.
* Identical to `hchacha_small`.
* Need to find a way to merge it with `chachaCore` without 25% performance hit.
*/
// prettier-ignore
export function hchacha(s, k, i, out) {
let x00 = s[0], x01 = s[1], x02 = s[2], x03 = s[3], x04 = k[0], x05 = k[1], x06 = k[2], x07 = k[3], x08 = k[4], x09 = k[5], x10 = k[6], x11 = k[7], x12 = i[0], x13 = i[1], x14 = i[2], x15 = i[3];
for (let r = 0; r < 20; r += 2) {
x00 = (x00 + x04) | 0;
x12 = rotl(x12 ^ x00, 16);
x08 = (x08 + x12) | 0;
x04 = rotl(x04 ^ x08, 12);
x00 = (x00 + x04) | 0;
x12 = rotl(x12 ^ x00, 8);
x08 = (x08 + x12) | 0;
x04 = rotl(x04 ^ x08, 7);
x01 = (x01 + x05) | 0;
x13 = rotl(x13 ^ x01, 16);
x09 = (x09 + x13) | 0;
x05 = rotl(x05 ^ x09, 12);
x01 = (x01 + x05) | 0;
x13 = rotl(x13 ^ x01, 8);
x09 = (x09 + x13) | 0;
x05 = rotl(x05 ^ x09, 7);
x02 = (x02 + x06) | 0;
x14 = rotl(x14 ^ x02, 16);
x10 = (x10 + x14) | 0;
x06 = rotl(x06 ^ x10, 12);
x02 = (x02 + x06) | 0;
x14 = rotl(x14 ^ x02, 8);
x10 = (x10 + x14) | 0;
x06 = rotl(x06 ^ x10, 7);
x03 = (x03 + x07) | 0;
x15 = rotl(x15 ^ x03, 16);
x11 = (x11 + x15) | 0;
x07 = rotl(x07 ^ x11, 12);
x03 = (x03 + x07) | 0;
x15 = rotl(x15 ^ x03, 8);
x11 = (x11 + x15) | 0;
x07 = rotl(x07 ^ x11, 7);
x00 = (x00 + x05) | 0;
x15 = rotl(x15 ^ x00, 16);
x10 = (x10 + x15) | 0;
x05 = rotl(x05 ^ x10, 12);
x00 = (x00 + x05) | 0;
x15 = rotl(x15 ^ x00, 8);
x10 = (x10 + x15) | 0;
x05 = rotl(x05 ^ x10, 7);
x01 = (x01 + x06) | 0;
x12 = rotl(x12 ^ x01, 16);
x11 = (x11 + x12) | 0;
x06 = rotl(x06 ^ x11, 12);
x01 = (x01 + x06) | 0;
x12 = rotl(x12 ^ x01, 8);
x11 = (x11 + x12) | 0;
x06 = rotl(x06 ^ x11, 7);
x02 = (x02 + x07) | 0;
x13 = rotl(x13 ^ x02, 16);
x08 = (x08 + x13) | 0;
x07 = rotl(x07 ^ x08, 12);
x02 = (x02 + x07) | 0;
x13 = rotl(x13 ^ x02, 8);
x08 = (x08 + x13) | 0;
x07 = rotl(x07 ^ x08, 7);
x03 = (x03 + x04) | 0;
x14 = rotl(x14 ^ x03, 16);
x09 = (x09 + x14) | 0;
x04 = rotl(x04 ^ x09, 12);
x03 = (x03 + x04) | 0;
x14 = rotl(x14 ^ x03, 8);
x09 = (x09 + x14) | 0;
x04 = rotl(x04 ^ x09, 7);
}
let oi = 0;
out[oi++] = x00;
out[oi++] = x01;
out[oi++] = x02;
out[oi++] = x03;
out[oi++] = x12;
out[oi++] = x13;
out[oi++] = x14;
out[oi++] = x15;
}
/** Original, non-RFC chacha20 from DJB. 8-byte nonce, 8-byte counter. */
export const chacha20orig = /* @__PURE__ */ createCipher(chachaCore, {
counterRight: false,
counterLength: 8,
allowShortKeys: true,
});
/**
* ChaCha stream cipher. Conforms to RFC 8439 (IETF, TLS). 12-byte nonce, 4-byte counter.
* With smaller nonce, it's not safe to make it random (CSPRNG), due to collision chance.
*/
export const chacha20 = /* @__PURE__ */ createCipher(chachaCore, {
counterRight: false,
counterLength: 4,
allowShortKeys: false,
});
/**
* XChaCha eXtended-nonce ChaCha. With 24-byte nonce, it's safe to make it random (CSPRNG).
* See [IRTF draft](https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-xchacha).
*/
export const xchacha20 = /* @__PURE__ */ createCipher(chachaCore, {
counterRight: false,
counterLength: 8,
extendNonceFn: hchacha,
allowShortKeys: false,
});
/** Reduced 8-round chacha, described in original paper. */
export const chacha8 = /* @__PURE__ */ createCipher(chachaCore, {
counterRight: false,
counterLength: 4,
rounds: 8,
});
/** Reduced 12-round chacha, described in original paper. */
export const chacha12 = /* @__PURE__ */ createCipher(chachaCore, {
counterRight: false,
counterLength: 4,
rounds: 12,
});
const ZEROS16 = /* @__PURE__ */ new Uint8Array(16);
// Pad to digest size with zeros
const updatePadded = (h, msg) => {
h.update(msg);
const leftover = msg.length % 16;
if (leftover)
h.update(ZEROS16.subarray(leftover));
};
const ZEROS32 = /* @__PURE__ */ new Uint8Array(32);
function computeTag(fn, key, nonce, ciphertext, AAD) {
if (AAD !== undefined)
abytes(AAD, undefined, 'AAD');
const authKey = fn(key, nonce, ZEROS32);
const lengths = u64Lengths(ciphertext.length, AAD ? AAD.length : 0, true);
// Methods below can be replaced with
// return poly1305_computeTag_small(authKey, lengths, ciphertext, AAD)
const h = poly1305.create(authKey);
if (AAD)
updatePadded(h, AAD);
updatePadded(h, ciphertext);
h.update(lengths);
const res = h.digest();
clean(authKey, lengths);
return res;
}
/**
* AEAD algorithm from RFC 8439.
* Salsa20 and chacha (RFC 8439) use poly1305 differently.
* We could have composed them, but it's hard because of authKey:
* In salsa20, authKey changes position in salsa stream.
* In chacha, authKey can't be computed inside computeTag, it modifies the counter.
*/
export const _poly1305_aead = (xorStream) => (key, nonce, AAD) => {
const tagLength = 16;
return {
encrypt(plaintext, output) {
const plength = plaintext.length;
output = getOutput(plength + tagLength, output, false);
output.set(plaintext);
const oPlain = output.subarray(0, -tagLength);
// Actual encryption
xorStream(key, nonce, oPlain, oPlain, 1);
const tag = computeTag(xorStream, key, nonce, oPlain, AAD);
output.set(tag, plength); // append tag
clean(tag);
return output;
},
decrypt(ciphertext, output) {
output = getOutput(ciphertext.length - tagLength, output, false);
const data = ciphertext.subarray(0, -tagLength);
const passedTag = ciphertext.subarray(-tagLength);
const tag = computeTag(xorStream, key, nonce, data, AAD);
if (!equalBytes(passedTag, tag))
throw new Error('invalid tag');
output.set(ciphertext.subarray(0, -tagLength));
// Actual decryption
xorStream(key, nonce, output, output, 1); // start stream with i=1
clean(tag);
return output;
},
};
};
/**
* ChaCha20-Poly1305 from RFC 8439.
*
* Unsafe to use random nonces under the same key, due to collision chance.
* Prefer XChaCha instead.
*/
export const chacha20poly1305 = /* @__PURE__ */ wrapCipher({ blockSize: 64, nonceLength: 12, tagLength: 16 }, _poly1305_aead(chacha20));
/**
* XChaCha20-Poly1305 extended-nonce chacha.
*
* Can be safely used with random nonces (CSPRNG).
* See [IRTF draft](https://datatracker.ietf.org/doc/html/draft-irtf-cfrg-xchacha).
*/
export const xchacha20poly1305 = /* @__PURE__ */ wrapCipher({ blockSize: 64, nonceLength: 24, tagLength: 16 }, _poly1305_aead(xchacha20));
/**
* Chacha20 CSPRNG (cryptographically secure pseudorandom number generator).
* It's best to limit usage to non-production, non-critical cases: for example, test-only.
* Compatible with libtomcrypt. It does not have a specification, so unclear how secure it is.
*/
export const rngChacha20 = /* @__PURE__ */ createPRG(chacha20orig, 64, 32, 8);
/**
* Chacha20/8 CSPRNG (cryptographically secure pseudorandom number generator).
* It's best to limit usage to non-production, non-critical cases: for example, test-only.
* Faster than `rngChacha20`.
*/
export const rngChacha8 = /* @__PURE__ */ createPRG(chacha8, 64, 32, 12);
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