include node_modules so release .zip is deployable

node_modules/@noble/ciphers/src/webcrypto/siv.ts

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+import { AsyncCipher, createView, setBigUint64 } from '../utils.js';
+import { polyval } from '../_polyval.js';
+import { getWebcryptoSubtle } from './utils.js';
+/**
+ * AES-GCM-SIV: classic AES-GCM with nonce-misuse resistance.
+ * RFC 8452, https://datatracker.ietf.org/doc/html/rfc8452
+ */
+
+// AES stuff (same as ff1)
+const BLOCK_LEN = 16;
+const IV = new Uint8Array(BLOCK_LEN);
+async function encryptBlock(msg: Uint8Array, key: Uint8Array): Promise<Uint8Array> {
+  if (key.length !== 16 && key.length !== 32) throw new Error('Invalid key length');
+  const mode = { name: `AES-CBC`, length: key.length * 8 };
+  const cr = getWebcryptoSubtle();
+  const wKey = await cr.importKey('raw', key, mode, true, ['encrypt']);
+  const cipher = await cr.encrypt({ name: `aes-cbc`, iv: IV, counter: IV, length: 64 }, wKey, msg);
+  return new Uint8Array(cipher).subarray(0, 16);
+}
+
+// Kinda constant-time equality
+function equalBytes(a: Uint8Array, b: Uint8Array): boolean {
+  // Should not happen
+  if (a.length !== b.length) throw new Error('equalBytes: Different size of Uint8Arrays');
+  let flag = true;
+  for (let i = 0; i < a.length; i++) if (a[i] !== b[i]) flag &&= false;
+  return flag;
+}
+// Wrap position so it will be in padded to blockSize
+const wrapPos = (pos: number, blockSize: number) => Math.ceil(pos / blockSize) * blockSize;
+
+const limit = (name: string, min: number, max: number) => (value: number) => {
+  if (!Number.isSafeInteger(value) || min > value || value > max)
+    throw new Error(`${name}: invalid value=${value}, must be [${min}..${max}]`);
+};
+
+// From RFC 8452: Section 6
+const AAD_LIMIT = limit('AAD', 0, 2 ** 36);
+const PLAIN_LIMIT = limit('Plaintext', 0, 2 ** 36);
+const NONCE_LIMIT = limit('Nonce', 12, 12);
+const CIPHER_LIMIT = limit('Ciphertext', 16, 2 ** 36 + 16);
+
+// nodejs api doesn't support 32bit counters, browser does
+async function ctr(key: Uint8Array, tag: Uint8Array, input: Uint8Array) {
+  // The initial counter block is the tag with the most significant bit of the last byte set to one.
+  let block = tag.slice();
+  block[15] |= 0x80;
+  let view = createView(block);
+  let output = new Uint8Array(input.length);
+  for (let pos = 0; pos < input.length; ) {
+    const encryptedBlock = await encryptBlock(block, key);
+    view.setUint32(0, view.getUint32(0, true) + 1, true);
+    const take = Math.min(input.length, encryptedBlock.length);
+    for (let j = 0; j < take; j++, pos++) output[pos] = encryptedBlock[j] ^ input[pos];
+  }
+  return new Uint8Array(output);
+}
+
+export async function deriveKeys(key: Uint8Array, nonce: Uint8Array) {
+  NONCE_LIMIT(nonce.length);
+  const len = key.length;
+  if (len !== 16 && len !== 32)
+    throw new Error(`key length must be 16 or 32 bytes, got: ${len} bytes`);
+  const encKey = new Uint8Array(len);
+  const authKey = new Uint8Array(16);
+  let counter = 0;
+  const deriveBlock = new Uint8Array(nonce.length + 4);
+  deriveBlock.set(nonce, 4);
+  const view = createView(deriveBlock);
+  for (const derivedKey of [authKey, encKey]) {
+    for (let i = 0; i < derivedKey.length; i += 8) {
+      view.setUint32(0, counter++, true);
+      const block = await encryptBlock(deriveBlock, key);
+      derivedKey.set(block.subarray(0, 8), i);
+    }
+  }
+  return { authKey, encKey };
+}
+
+export async function aes_256_gcm_siv(
+  key: Uint8Array,
+  nonce: Uint8Array,
+  AAD: Uint8Array
+): Promise<AsyncCipher> {
+  const { encKey, authKey } = await deriveKeys(key, nonce);
+  const computeTag = async (data: Uint8Array, AAD: Uint8Array) => {
+    const dataPos = wrapPos(AAD.length, 16);
+    const lenPos = wrapPos(dataPos + data.length, 16);
+    const block = new Uint8Array(lenPos + 16);
+    const view = createView(block);
+    block.set(AAD);
+    block.set(data, dataPos);
+    setBigUint64(view, lenPos, BigInt(AAD.length * 8), true);
+    setBigUint64(view, lenPos + 8, BigInt(data.length * 8), true);
+    // Compute the expected tag by XORing S_s and the nonce, clearing the
+    // most significant bit of the last byte and encrypting with the
+    // message-encryption key.
+    const tag = polyval(authKey, block);
+    for (let i = 0; i < 12; i++) tag[i] ^= nonce[i];
+    // Clear the highest bit
+    tag[15] &= 0x7f;
+    return await encryptBlock(tag, encKey);
+  };
+  return {
+    //    computeTag,
+    encrypt: async (plaintext: Uint8Array) => {
+      AAD_LIMIT(AAD.length);
+      PLAIN_LIMIT(plaintext.length);
+      const tag = await computeTag(plaintext, AAD);
+      const out = new Uint8Array(plaintext.length + 16);
+      out.set(tag, plaintext.length);
+      out.set(await ctr(encKey, tag, plaintext));
+      return out;
+    },
+    decrypt: async (ciphertext: Uint8Array) => {
+      CIPHER_LIMIT(ciphertext.length);
+      AAD_LIMIT(AAD.length);
+      const tag = ciphertext.subarray(-16);
+      const plaintext = await ctr(encKey, tag, ciphertext.subarray(0, -16));
+      const expectedTag = await computeTag(plaintext, AAD);
+      if (!equalBytes(tag, expectedTag)) throw new Error('invalid poly1305 tag');
+      return plaintext;
+    },
+  };
+}