This is documentation for the next version of Grafana k6 documentation. For the latest stable release, go to the latest version.

Documentationbreadcrumb arrow Grafana k6breadcrumb arrow JavaScript APIbreadcrumb arrow cryptobreadcrumb arrow SubtleCryptobreadcrumb arrow deriveKey
Open source

deriveKey

The deriveKey() method derives a secret key from a master key. It takes as arguments a base key, the derivation algorithm to use, and the desired properties for the key to derive. It returns a Promise which will be fulfilled with a CryptoKey object representing the new key.

Usage

deriveKey(algorithm, baseKey, derivedKeyType, extractable, keyUsages)

Parameters

NameTypeDescription
algorithmPbkdf2ParamsAn object defining the derivation algorithm to use.
baseKeyCryptoKeyThe base key to derive the new key from. For PBKDF2, this is the password imported as a CryptoKey.
derivedKeyTypeobject with name and length propertiesAn object defining the algorithm the derived key will be used for. Must include name (e.g., AES-GCM, AES-CBC, AES-CTR, AES-KW) and length (e.g., 256).
extractablebooleanWhether the key can be exported using exportKey.
keyUsagesArray<string>An array indicating what the key can be used for (e.g., encrypt, decrypt).

Supported algorithms

PBKDF2ECDHHKDF
✅ Pbkdf2Params❌❌

Supported derived key algorithms

AES-CBCAES-CTRAES-GCMAES-KWHMAC
✅✅✅✅❌

Return Value

A Promise that resolves to a new CryptoKey object.

Example

JavaScript 
export default async function () {
  const password = stringToArrayBuffer('my secret password');

  // Import the password as a key
  const baseKey = await crypto.subtle.importKey('raw', password, 'PBKDF2', false, [
    'deriveBits',
    'deriveKey',
  ]);

  // Generate a random salt
  const salt = crypto.getRandomValues(new Uint8Array(16));

  // Derive an AES-GCM key using PBKDF2
  const derivedKey = await crypto.subtle.deriveKey(
    {
      name: 'PBKDF2',
      hash: 'SHA-256',
      salt: salt,
      iterations: 310000,
    },
    baseKey,
    {
      name: 'AES-GCM',
      length: 256,
    },
    true,
    ['encrypt', 'decrypt']
  );

  console.log('derived key: ' + JSON.stringify(derivedKey));
}

function stringToArrayBuffer(str) {
  const buf = new ArrayBuffer(str.length * 2);
  const bufView = new Uint16Array(buf);
  for (let i = 0, strLen = str.length; i < strLen; i++) {
    bufView[i] = str.charCodeAt(i);
  }
  return buf;
}