Function diffieHellman

lib/internal/crypto/diffiehellman.js:288–370

(options, callback)

const dhEnabledKeyTypes = new SafeSet(['dh', 'ec', 'x448', 'x25519']);

function diffieHellman(options, callback) {
  validateObject(options, 'options');

  if (callback !== undefined)
    validateFunction(callback, 'callback');

  const { privateKey, publicKey } = options;

  // TODO(@panva): remove these non-semver-major error code preserving measures
  // in a semver-major followup, the final state is just preparePublicOrPrivateKey
  // and preparePrivateKey
  if (privateKey == null)
    throw new ERR_INVALID_ARG_VALUE('options.privateKey', privateKey);

  if (publicKey == null)
    throw new ERR_INVALID_ARG_VALUE('options.publicKey', publicKey);

  if (isKeyObject(privateKey)) {
    const type = getKeyObjectType(privateKey);
    if (type !== 'private')
      throw new ERR_CRYPTO_INVALID_KEY_OBJECT_TYPE(type, 'private');
  }

  if (isKeyObject(publicKey)) {
    const type = getKeyObjectType(publicKey);
    if (type !== 'public' && type !== 'private') {
      throw new ERR_CRYPTO_INVALID_KEY_OBJECT_TYPE(type,
                                                   'private or public');
    }
  }

  if (isKeyObject(privateKey) && isKeyObject(publicKey)) {
    const privateType = getKeyObjectAsymmetricKeyType(privateKey);
    const publicType = getKeyObjectAsymmetricKeyType(publicKey);
    if (privateType !== publicType || !dhEnabledKeyTypes.has(privateType)) {
      throw new ERR_CRYPTO_INCOMPATIBLE_KEY('key types for Diffie-Hellman',
                                            `${privateType} and ${publicType}`);
    }
  }

  const {
    data: pubData,
    format: pubFormat,
    type: pubType,
    passphrase: pubPassphrase,
    namedCurve: pubNamedCurve,
  } = preparePublicOrPrivateKey(publicKey, 'options.publicKey');

  const {
    data: privData,
    format: privFormat,
    type: privType,
    passphrase: privPassphrase,
    namedCurve: privNamedCurve,
  } = preparePrivateKey(privateKey, 'options.privateKey');

  const job = new DHBitsJob(
    callback ? kCryptoJobAsync : kCryptoJobSync,