167 lines
6.5 KiB
JavaScript
167 lines
6.5 KiB
JavaScript
/**
|
|
* WebCrypto-based AES gcm/ctr/cbc, `managedNonce` and `randomBytes`.
|
|
* We use WebCrypto aka globalThis.crypto, which exists in browsers and node.js 16+.
|
|
* @module
|
|
*/
|
|
import { abytes, anumber } from "./utils.js";
|
|
function getWebcryptoSubtle() {
|
|
const cr = typeof globalThis !== 'undefined' && globalThis.crypto;
|
|
if (cr && typeof cr.subtle === 'object' && cr.subtle != null)
|
|
return cr.subtle;
|
|
throw new Error('crypto.subtle must be defined');
|
|
}
|
|
/**
|
|
* Internal webcrypto utils. Can be overridden if crypto.subtle is not present,
|
|
* for example in React Native.
|
|
* Raw keys are re-imported on every call; this wrapper intentionally does not
|
|
* cache `CryptoKey` objects between operations.
|
|
*/
|
|
export const utils = {
|
|
async encrypt(key, keyParams, cryptParams, plaintext) {
|
|
const cr = getWebcryptoSubtle();
|
|
const iKey = await cr.importKey('raw', key, keyParams, true, ['encrypt']);
|
|
const ciphertext = await cr.encrypt(cryptParams, iKey, plaintext);
|
|
return new Uint8Array(ciphertext);
|
|
},
|
|
async decrypt(key, keyParams, cryptParams, ciphertext) {
|
|
const cr = getWebcryptoSubtle();
|
|
const iKey = await cr.importKey('raw', key, keyParams, true, ['decrypt']);
|
|
const plaintext = await cr.decrypt(cryptParams, iKey, ciphertext);
|
|
return new Uint8Array(plaintext);
|
|
},
|
|
};
|
|
const mode = {
|
|
CBC: 'AES-CBC',
|
|
CTR: 'AES-CTR',
|
|
GCM: 'AES-GCM',
|
|
};
|
|
function getCryptParams(algo, nonce, AAD) {
|
|
if (algo === mode.CBC)
|
|
return { name: mode.CBC, iv: nonce };
|
|
// WebCrypto allows 1..128 counter bits; use the full block to match sync ctr() / Node CTR wrap.
|
|
if (algo === mode.CTR)
|
|
return { name: mode.CTR, counter: nonce, length: 128 };
|
|
if (algo === mode.GCM) {
|
|
// Rely on the backend default tag length (128 bits) instead of setting it explicitly.
|
|
if (AAD)
|
|
return { name: mode.GCM, iv: nonce, additionalData: AAD };
|
|
else
|
|
return { name: mode.GCM, iv: nonce };
|
|
}
|
|
throw new Error('unknown aes block mode');
|
|
}
|
|
function generate(algo, nonceLength) {
|
|
anumber(nonceLength);
|
|
const res = (key, nonce, AAD) => {
|
|
abytes(key);
|
|
abytes(nonce);
|
|
// Reject falsy non-byte AAD locally; otherwise false/0/''/null silently become "no AAD".
|
|
if (AAD !== undefined)
|
|
abytes(AAD, undefined, 'AAD');
|
|
// Exact nonce-length enforcement and WebCrypto-specific AAD normalization are
|
|
// delegated to the backend; locally we only require byte-array inputs here.
|
|
// Keep caller key/nonce/AAD by reference; mutating them after
|
|
// construction changes later operations.
|
|
const keyParams = { name: algo, length: key.length * 8 };
|
|
const cryptParams = getCryptParams(algo, nonce, AAD);
|
|
let consumed = false;
|
|
return {
|
|
// keyLength,
|
|
encrypt(plaintext) {
|
|
abytes(plaintext);
|
|
if (consumed)
|
|
throw new Error('Cannot encrypt() twice with same key / nonce');
|
|
consumed = true;
|
|
return utils.encrypt(key, keyParams, cryptParams, plaintext);
|
|
},
|
|
decrypt(ciphertext) {
|
|
abytes(ciphertext);
|
|
return utils.decrypt(key, keyParams, cryptParams, ciphertext);
|
|
},
|
|
};
|
|
};
|
|
res.nonceLength = nonceLength;
|
|
res.blockSize = 16; // always for AES
|
|
return res;
|
|
}
|
|
/**
|
|
* AES-CBC implemented with WebCrypto.
|
|
* Uses WebCrypto's built-in PKCS padding behavior; exact IV-length checks are
|
|
* delegated to the backend instead of local `abytes(..., 16)` validation.
|
|
* @param key - AES key bytes.
|
|
* @param iv - 16-byte initialization vector.
|
|
* @returns Async cipher instance.
|
|
* @example
|
|
* Encrypts a block with the browser or Node WebCrypto backend.
|
|
*
|
|
* ```ts
|
|
* import { cbc } from '@noble/ciphers/webcrypto.js';
|
|
* import { randomBytes } from '@noble/ciphers/utils.js';
|
|
* const key = randomBytes(16);
|
|
* const iv = randomBytes(16);
|
|
* const cipher = cbc(key, iv);
|
|
* await cipher.encrypt(new Uint8Array(16));
|
|
* ```
|
|
*/
|
|
export const cbc = /* @__PURE__ */ (() => generate(mode.CBC, 16))();
|
|
/**
|
|
* AES-CTR implemented with WebCrypto.
|
|
* Uses WebCrypto's full 128-bit counter-length setting so the whole
|
|
* 16-byte counter block is incremented, matching sync `aes.ts:ctr`.
|
|
* @param key - AES key bytes.
|
|
* @param nonce - 16-byte counter block incremented as a full big-endian AES counter block.
|
|
* @returns Async cipher instance.
|
|
* @example
|
|
* Encrypts a short payload with WebCrypto AES-CTR.
|
|
*
|
|
* ```ts
|
|
* import { ctr } from '@noble/ciphers/webcrypto.js';
|
|
* import { randomBytes } from '@noble/ciphers/utils.js';
|
|
* const key = randomBytes(16);
|
|
* const nonce = randomBytes(16);
|
|
* const cipher = ctr(key, nonce);
|
|
* await cipher.encrypt(new Uint8Array([1, 2, 3]));
|
|
* ```
|
|
*/
|
|
export const ctr = /* @__PURE__ */ (() => generate(mode.CTR, 16))();
|
|
/**
|
|
* AES-GCM implemented with WebCrypto.
|
|
* AAD type normalization and nonce-shape enforcement beyond raw bytes are left
|
|
* to the backend WebCrypto implementation.
|
|
* @param key - AES key bytes.
|
|
* @param nonce - Nonce bytes.
|
|
* @param AAD - Additional authenticated data.
|
|
* @returns Async cipher instance.
|
|
* @example
|
|
* Encrypts and authenticates plaintext with WebCrypto AES-GCM.
|
|
*
|
|
* ```ts
|
|
* import { gcm } from '@noble/ciphers/webcrypto.js';
|
|
* import { randomBytes } from '@noble/ciphers/utils.js';
|
|
* const key = randomBytes(16);
|
|
* const nonce = randomBytes(12);
|
|
* const cipher = gcm(key, nonce);
|
|
* await cipher.encrypt(new Uint8Array([1, 2, 3]));
|
|
* ```
|
|
*/
|
|
export const gcm = /* @__PURE__ */ (() => generate(mode.GCM, 12))();
|
|
// // Type tests
|
|
// import { siv, gcm, ctr, ecb, cbc } from '../aes.ts';
|
|
// import { xsalsa20poly1305 } from '../salsa.ts';
|
|
// import { chacha20poly1305, xchacha20poly1305 } from '../chacha.ts';
|
|
// const wsiv = managedNonce(siv);
|
|
// const wgcm = managedNonce(gcm);
|
|
// const wctr = managedNonce(ctr);
|
|
// const wcbc = managedNonce(cbc);
|
|
// const wsalsapoly = managedNonce(xsalsa20poly1305);
|
|
// const wchacha = managedNonce(chacha20poly1305);
|
|
// const wxchacha = managedNonce(xchacha20poly1305);
|
|
// // should fail
|
|
// const wcbc2 = managedNonce(managedNonce(cbc));
|
|
// const wctr = managedNonce(ctr);
|
|
// import { gcm as gcmSync } from '../aes.ts';
|
|
// const x1 = managedNonce(gcmSync);
|
|
// // const x1: (key: Uint8Array, AAD?: Uint8Array | undefined) => Cipher
|
|
// const x2 = managedNonce(gcm);
|
|
// // const x2: (key: Uint8Array, AAD?: Uint8Array | undefined) => AsyncCipher
|
|
//# sourceMappingURL=webcrypto.js.map
|