Function deriveKeyImpl

lib/internal/crypto/webcrypto.js:347–421

(
  algorithm,
  baseKey,
  derivedKeyType,
  extractable,
  keyUsages)

}

function deriveKeyImpl(
  algorithm,
  baseKey,
  derivedKeyType,
  extractable,
  keyUsages) {
  const prefix = prepareSubtleMethod(this, 'deriveKey', arguments.length, 5);
  let i = 0;
  algorithm = convertSubtleArgument(
    prefix, 'AlgorithmIdentifier', algorithm, i++);
  baseKey = convertSubtleArgument(prefix, 'CryptoKey', baseKey, i++);
  derivedKeyType = convertSubtleArgument(
    prefix, 'AlgorithmIdentifier', derivedKeyType, i++);
  extractable = convertSubtleArgument(prefix, 'boolean', extractable, i++);
  const usages = convertSubtleArgument(
    prefix, 'sequence<KeyUsage>', keyUsages, i++);

  const normalizedAlgorithm = normalizeAlgorithm(algorithm, 'deriveBits');
  const normalizedDerivedKeyAlgorithmImport =
    normalizeAlgorithm(derivedKeyType, 'importKey');
  const normalizedDerivedKeyAlgorithmLength =
    normalizeAlgorithm(derivedKeyType, 'get key length');
  if (!hasCryptoKeyUsage(baseKey, 'deriveKey')) {
    throw lazyDOMException(
      'baseKey does not have deriveKey usage',
      'InvalidAccessError');
  }
  if (getCryptoKeyAlgorithm(baseKey).name !== normalizedAlgorithm.name)
    throw lazyDOMException('Key algorithm mismatch', 'InvalidAccessError');

  const length = getKeyLength(normalizedDerivedKeyAlgorithmLength);
  let secret;
  switch (normalizedAlgorithm.name) {
    case 'X25519':
      // Fall through
    case 'X448':
      // Fall through
    case 'ECDH':
      secret = require('internal/crypto/diffiehellman')
        .ecdhDeriveBits(normalizedAlgorithm, baseKey, length);
      break;
    case 'HKDF':
      secret = require('internal/crypto/hkdf')
        .hkdfDeriveBits(normalizedAlgorithm, baseKey, length);
      break;
    case 'PBKDF2':
      secret = require('internal/crypto/pbkdf2')
        .pbkdf2DeriveBits(normalizedAlgorithm, baseKey, length);
      break;
    case 'Argon2d':
      // Fall through
    case 'Argon2i':
      // Fall through
    case 'Argon2id':
      secret = require('internal/crypto/argon2')
        .argon2DeriveBits(normalizedAlgorithm, baseKey, length);
      break;
    /* c8 ignore start */