Function macImportKey

lib/internal/crypto/mac.js:105–166

(
  format,
  keyData,
  algorithm,
  extractable,
  usages,
)

}

function macImportKey(
  format,
  keyData,
  algorithm,
  extractable,
  usages,
) {
  const isHmac = algorithm.name === 'HMAC';
  const usagesSet = validateKeyUsages(
    usages, kUsages, algorithm.name);
  let handle;
  let length;
  switch (format) {
    case 'KeyObjectHandle': {
      handle = keyData;
      break;
    }
    case 'raw-secret':
    case 'raw': {
      if (format === 'raw' && !isHmac) {
        return undefined;
      }
      handle = importSecretKey(keyData);
      break;
    }
    case 'jwk': {
      validateJwk(keyData, 'oct', extractable, usagesSet, 'sig');

      if (keyData.alg !== undefined) {
        const expected = isHmac ?
          normalizeHashName(algorithm.hash.name, normalizeHashName.kContextJwkHmac) :
          `K${StringPrototypeSubstring(algorithm.name, 4)}`;
        if (expected && keyData.alg !== expected)
          throw lazyDOMException(
            'JWK "alg" does not match the requested algorithm',
            'DataError');
      }

      handle = importJwkSecretKey(keyData);
      break;
    }
    default:
      return undefined;
  }

  ({ handle, length } = normalizeKeyLength(handle, algorithm)); // eslint-disable-line prefer-const

  const algorithmObject = {
    name: algorithm.name,
    length,
  };

  if (isHmac) {
    algorithmObject.hash = algorithm.hash;
  }

  return new InternalCryptoKey(
    handle,