/** * 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