277 lines
10 KiB
JavaScript
277 lines
10 KiB
JavaScript
/**
|
|
* Poly1305 ([PDF](https://cr.yp.to/mac/poly1305-20050329.pdf),
|
|
* [wiki](https://en.wikipedia.org/wiki/Poly1305))
|
|
* is a fast and parallel secret-key message-authentication code suitable for
|
|
* a wide variety of applications. It was standardized in
|
|
* [RFC 8439](https://datatracker.ietf.org/doc/html/rfc8439) and is now used in TLS 1.3.
|
|
*
|
|
* Polynomial MACs are not perfect for every situation:
|
|
* they lack Random Key Robustness: the MAC can be forged, and can't be used in PAKE schemes.
|
|
* See [invisible salamanders attack](https://keymaterial.net/2020/09/07/invisible-salamanders-in-aes-gcm-siv/).
|
|
* To combat invisible salamanders, `hash(key)` can be included in ciphertext,
|
|
* however, this would violate ciphertext indistinguishability:
|
|
* an attacker would know which key was used - so `HKDF(key, i)`
|
|
* could be used instead.
|
|
*
|
|
* Check out [original website](https://cr.yp.to/mac.html).
|
|
* @module
|
|
*/
|
|
import { abytes, aexists, aoutput } from './_assert.js';
|
|
import { Hash, clean, toBytes } from './utils.js';
|
|
// Based on Public Domain poly1305-donna https://github.com/floodyberry/poly1305-donna
|
|
const u8to16 = (a, i) => (a[i++] & 0xff) | ((a[i++] & 0xff) << 8);
|
|
class Poly1305 {
|
|
constructor(key) {
|
|
this.blockLen = 16;
|
|
this.outputLen = 16;
|
|
this.buffer = new Uint8Array(16);
|
|
this.r = new Uint16Array(10);
|
|
this.h = new Uint16Array(10);
|
|
this.pad = new Uint16Array(8);
|
|
this.pos = 0;
|
|
this.finished = false;
|
|
key = toBytes(key);
|
|
abytes(key, 32);
|
|
const t0 = u8to16(key, 0);
|
|
const t1 = u8to16(key, 2);
|
|
const t2 = u8to16(key, 4);
|
|
const t3 = u8to16(key, 6);
|
|
const t4 = u8to16(key, 8);
|
|
const t5 = u8to16(key, 10);
|
|
const t6 = u8to16(key, 12);
|
|
const t7 = u8to16(key, 14);
|
|
// https://github.com/floodyberry/poly1305-donna/blob/e6ad6e091d30d7f4ec2d4f978be1fcfcbce72781/poly1305-donna-16.h#L47
|
|
this.r[0] = t0 & 0x1fff;
|
|
this.r[1] = ((t0 >>> 13) | (t1 << 3)) & 0x1fff;
|
|
this.r[2] = ((t1 >>> 10) | (t2 << 6)) & 0x1f03;
|
|
this.r[3] = ((t2 >>> 7) | (t3 << 9)) & 0x1fff;
|
|
this.r[4] = ((t3 >>> 4) | (t4 << 12)) & 0x00ff;
|
|
this.r[5] = (t4 >>> 1) & 0x1ffe;
|
|
this.r[6] = ((t4 >>> 14) | (t5 << 2)) & 0x1fff;
|
|
this.r[7] = ((t5 >>> 11) | (t6 << 5)) & 0x1f81;
|
|
this.r[8] = ((t6 >>> 8) | (t7 << 8)) & 0x1fff;
|
|
this.r[9] = (t7 >>> 5) & 0x007f;
|
|
for (let i = 0; i < 8; i++)
|
|
this.pad[i] = u8to16(key, 16 + 2 * i);
|
|
}
|
|
process(data, offset, isLast = false) {
|
|
const hibit = isLast ? 0 : 1 << 11;
|
|
const { h, r } = this;
|
|
const r0 = r[0];
|
|
const r1 = r[1];
|
|
const r2 = r[2];
|
|
const r3 = r[3];
|
|
const r4 = r[4];
|
|
const r5 = r[5];
|
|
const r6 = r[6];
|
|
const r7 = r[7];
|
|
const r8 = r[8];
|
|
const r9 = r[9];
|
|
const t0 = u8to16(data, offset + 0);
|
|
const t1 = u8to16(data, offset + 2);
|
|
const t2 = u8to16(data, offset + 4);
|
|
const t3 = u8to16(data, offset + 6);
|
|
const t4 = u8to16(data, offset + 8);
|
|
const t5 = u8to16(data, offset + 10);
|
|
const t6 = u8to16(data, offset + 12);
|
|
const t7 = u8to16(data, offset + 14);
|
|
let h0 = h[0] + (t0 & 0x1fff);
|
|
let h1 = h[1] + (((t0 >>> 13) | (t1 << 3)) & 0x1fff);
|
|
let h2 = h[2] + (((t1 >>> 10) | (t2 << 6)) & 0x1fff);
|
|
let h3 = h[3] + (((t2 >>> 7) | (t3 << 9)) & 0x1fff);
|
|
let h4 = h[4] + (((t3 >>> 4) | (t4 << 12)) & 0x1fff);
|
|
let h5 = h[5] + ((t4 >>> 1) & 0x1fff);
|
|
let h6 = h[6] + (((t4 >>> 14) | (t5 << 2)) & 0x1fff);
|
|
let h7 = h[7] + (((t5 >>> 11) | (t6 << 5)) & 0x1fff);
|
|
let h8 = h[8] + (((t6 >>> 8) | (t7 << 8)) & 0x1fff);
|
|
let h9 = h[9] + ((t7 >>> 5) | hibit);
|
|
let c = 0;
|
|
let d0 = c + h0 * r0 + h1 * (5 * r9) + h2 * (5 * r8) + h3 * (5 * r7) + h4 * (5 * r6);
|
|
c = d0 >>> 13;
|
|
d0 &= 0x1fff;
|
|
d0 += h5 * (5 * r5) + h6 * (5 * r4) + h7 * (5 * r3) + h8 * (5 * r2) + h9 * (5 * r1);
|
|
c += d0 >>> 13;
|
|
d0 &= 0x1fff;
|
|
let d1 = c + h0 * r1 + h1 * r0 + h2 * (5 * r9) + h3 * (5 * r8) + h4 * (5 * r7);
|
|
c = d1 >>> 13;
|
|
d1 &= 0x1fff;
|
|
d1 += h5 * (5 * r6) + h6 * (5 * r5) + h7 * (5 * r4) + h8 * (5 * r3) + h9 * (5 * r2);
|
|
c += d1 >>> 13;
|
|
d1 &= 0x1fff;
|
|
let d2 = c + h0 * r2 + h1 * r1 + h2 * r0 + h3 * (5 * r9) + h4 * (5 * r8);
|
|
c = d2 >>> 13;
|
|
d2 &= 0x1fff;
|
|
d2 += h5 * (5 * r7) + h6 * (5 * r6) + h7 * (5 * r5) + h8 * (5 * r4) + h9 * (5 * r3);
|
|
c += d2 >>> 13;
|
|
d2 &= 0x1fff;
|
|
let d3 = c + h0 * r3 + h1 * r2 + h2 * r1 + h3 * r0 + h4 * (5 * r9);
|
|
c = d3 >>> 13;
|
|
d3 &= 0x1fff;
|
|
d3 += h5 * (5 * r8) + h6 * (5 * r7) + h7 * (5 * r6) + h8 * (5 * r5) + h9 * (5 * r4);
|
|
c += d3 >>> 13;
|
|
d3 &= 0x1fff;
|
|
let d4 = c + h0 * r4 + h1 * r3 + h2 * r2 + h3 * r1 + h4 * r0;
|
|
c = d4 >>> 13;
|
|
d4 &= 0x1fff;
|
|
d4 += h5 * (5 * r9) + h6 * (5 * r8) + h7 * (5 * r7) + h8 * (5 * r6) + h9 * (5 * r5);
|
|
c += d4 >>> 13;
|
|
d4 &= 0x1fff;
|
|
let d5 = c + h0 * r5 + h1 * r4 + h2 * r3 + h3 * r2 + h4 * r1;
|
|
c = d5 >>> 13;
|
|
d5 &= 0x1fff;
|
|
d5 += h5 * r0 + h6 * (5 * r9) + h7 * (5 * r8) + h8 * (5 * r7) + h9 * (5 * r6);
|
|
c += d5 >>> 13;
|
|
d5 &= 0x1fff;
|
|
let d6 = c + h0 * r6 + h1 * r5 + h2 * r4 + h3 * r3 + h4 * r2;
|
|
c = d6 >>> 13;
|
|
d6 &= 0x1fff;
|
|
d6 += h5 * r1 + h6 * r0 + h7 * (5 * r9) + h8 * (5 * r8) + h9 * (5 * r7);
|
|
c += d6 >>> 13;
|
|
d6 &= 0x1fff;
|
|
let d7 = c + h0 * r7 + h1 * r6 + h2 * r5 + h3 * r4 + h4 * r3;
|
|
c = d7 >>> 13;
|
|
d7 &= 0x1fff;
|
|
d7 += h5 * r2 + h6 * r1 + h7 * r0 + h8 * (5 * r9) + h9 * (5 * r8);
|
|
c += d7 >>> 13;
|
|
d7 &= 0x1fff;
|
|
let d8 = c + h0 * r8 + h1 * r7 + h2 * r6 + h3 * r5 + h4 * r4;
|
|
c = d8 >>> 13;
|
|
d8 &= 0x1fff;
|
|
d8 += h5 * r3 + h6 * r2 + h7 * r1 + h8 * r0 + h9 * (5 * r9);
|
|
c += d8 >>> 13;
|
|
d8 &= 0x1fff;
|
|
let d9 = c + h0 * r9 + h1 * r8 + h2 * r7 + h3 * r6 + h4 * r5;
|
|
c = d9 >>> 13;
|
|
d9 &= 0x1fff;
|
|
d9 += h5 * r4 + h6 * r3 + h7 * r2 + h8 * r1 + h9 * r0;
|
|
c += d9 >>> 13;
|
|
d9 &= 0x1fff;
|
|
c = ((c << 2) + c) | 0;
|
|
c = (c + d0) | 0;
|
|
d0 = c & 0x1fff;
|
|
c = c >>> 13;
|
|
d1 += c;
|
|
h[0] = d0;
|
|
h[1] = d1;
|
|
h[2] = d2;
|
|
h[3] = d3;
|
|
h[4] = d4;
|
|
h[5] = d5;
|
|
h[6] = d6;
|
|
h[7] = d7;
|
|
h[8] = d8;
|
|
h[9] = d9;
|
|
}
|
|
finalize() {
|
|
const { h, pad } = this;
|
|
const g = new Uint16Array(10);
|
|
let c = h[1] >>> 13;
|
|
h[1] &= 0x1fff;
|
|
for (let i = 2; i < 10; i++) {
|
|
h[i] += c;
|
|
c = h[i] >>> 13;
|
|
h[i] &= 0x1fff;
|
|
}
|
|
h[0] += c * 5;
|
|
c = h[0] >>> 13;
|
|
h[0] &= 0x1fff;
|
|
h[1] += c;
|
|
c = h[1] >>> 13;
|
|
h[1] &= 0x1fff;
|
|
h[2] += c;
|
|
g[0] = h[0] + 5;
|
|
c = g[0] >>> 13;
|
|
g[0] &= 0x1fff;
|
|
for (let i = 1; i < 10; i++) {
|
|
g[i] = h[i] + c;
|
|
c = g[i] >>> 13;
|
|
g[i] &= 0x1fff;
|
|
}
|
|
g[9] -= 1 << 13;
|
|
let mask = (c ^ 1) - 1;
|
|
for (let i = 0; i < 10; i++)
|
|
g[i] &= mask;
|
|
mask = ~mask;
|
|
for (let i = 0; i < 10; i++)
|
|
h[i] = (h[i] & mask) | g[i];
|
|
h[0] = (h[0] | (h[1] << 13)) & 0xffff;
|
|
h[1] = ((h[1] >>> 3) | (h[2] << 10)) & 0xffff;
|
|
h[2] = ((h[2] >>> 6) | (h[3] << 7)) & 0xffff;
|
|
h[3] = ((h[3] >>> 9) | (h[4] << 4)) & 0xffff;
|
|
h[4] = ((h[4] >>> 12) | (h[5] << 1) | (h[6] << 14)) & 0xffff;
|
|
h[5] = ((h[6] >>> 2) | (h[7] << 11)) & 0xffff;
|
|
h[6] = ((h[7] >>> 5) | (h[8] << 8)) & 0xffff;
|
|
h[7] = ((h[8] >>> 8) | (h[9] << 5)) & 0xffff;
|
|
let f = h[0] + pad[0];
|
|
h[0] = f & 0xffff;
|
|
for (let i = 1; i < 8; i++) {
|
|
f = (((h[i] + pad[i]) | 0) + (f >>> 16)) | 0;
|
|
h[i] = f & 0xffff;
|
|
}
|
|
clean(g);
|
|
}
|
|
update(data) {
|
|
aexists(this);
|
|
const { buffer, blockLen } = this;
|
|
data = toBytes(data);
|
|
const len = data.length;
|
|
for (let pos = 0; pos < len;) {
|
|
const take = Math.min(blockLen - this.pos, len - pos);
|
|
// Fast path: we have at least one block in input
|
|
if (take === blockLen) {
|
|
for (; blockLen <= len - pos; pos += blockLen)
|
|
this.process(data, pos);
|
|
continue;
|
|
}
|
|
buffer.set(data.subarray(pos, pos + take), this.pos);
|
|
this.pos += take;
|
|
pos += take;
|
|
if (this.pos === blockLen) {
|
|
this.process(buffer, 0, false);
|
|
this.pos = 0;
|
|
}
|
|
}
|
|
return this;
|
|
}
|
|
destroy() {
|
|
clean(this.h, this.r, this.buffer, this.pad);
|
|
}
|
|
digestInto(out) {
|
|
aexists(this);
|
|
aoutput(out, this);
|
|
this.finished = true;
|
|
const { buffer, h } = this;
|
|
let { pos } = this;
|
|
if (pos) {
|
|
buffer[pos++] = 1;
|
|
for (; pos < 16; pos++)
|
|
buffer[pos] = 0;
|
|
this.process(buffer, 0, true);
|
|
}
|
|
this.finalize();
|
|
let opos = 0;
|
|
for (let i = 0; i < 8; i++) {
|
|
out[opos++] = h[i] >>> 0;
|
|
out[opos++] = h[i] >>> 8;
|
|
}
|
|
return out;
|
|
}
|
|
digest() {
|
|
const { buffer, outputLen } = this;
|
|
this.digestInto(buffer);
|
|
const res = buffer.slice(0, outputLen);
|
|
this.destroy();
|
|
return res;
|
|
}
|
|
}
|
|
export function wrapConstructorWithKey(hashCons) {
|
|
const hashC = (msg, key) => hashCons(key).update(toBytes(msg)).digest();
|
|
const tmp = hashCons(new Uint8Array(32));
|
|
hashC.outputLen = tmp.outputLen;
|
|
hashC.blockLen = tmp.blockLen;
|
|
hashC.create = (key) => hashCons(key);
|
|
return hashC;
|
|
}
|
|
/** Poly1305 MAC from RFC 8439. */
|
|
export const poly1305 = wrapConstructorWithKey((key) => new Poly1305(key));
|
|
//# sourceMappingURL=_poly1305.js.map
|