Function DiffieHellman

lib/internal/crypto/diffiehellman.js:83–140

(sizeOrKey, keyEncoding, generator, genEncoding)

const DH_GENERATOR = 2;

function DiffieHellman(sizeOrKey, keyEncoding, generator, genEncoding) {
  if (!(this instanceof DiffieHellman))
    return new DiffieHellman(sizeOrKey, keyEncoding, generator, genEncoding);

  if (typeof sizeOrKey !== 'number' &&
      typeof sizeOrKey !== 'string' &&
      !isArrayBufferView(sizeOrKey) &&
      !isAnyArrayBuffer(sizeOrKey)) {
    throw new ERR_INVALID_ARG_TYPE(
      'sizeOrKey',
      ['number', 'string', 'ArrayBuffer', 'Buffer', 'TypedArray', 'DataView'],
      sizeOrKey,
    );
  }

  // Sizes < 0 don't make sense but they _are_ accepted (and subsequently
  // rejected with ERR_OSSL_BN_BITS_TOO_SMALL) by OpenSSL. The glue code
  // in node_crypto.cc accepts values that are IsInt32() for that reason
  // and that's why we do that here too.
  if (typeof sizeOrKey === 'number') {
    validateInt32(sizeOrKey, 'sizeOrKey');
    // Coerce -0 to +0.
    sizeOrKey += 0;
  }

  if (keyEncoding && !Buffer.isEncoding(keyEncoding) &&
      keyEncoding !== 'buffer') {
    genEncoding = generator;
    generator = keyEncoding;
    keyEncoding = false;
  }

  if (typeof sizeOrKey !== 'number')
    sizeOrKey = toBuf(sizeOrKey, keyEncoding);

  if (!generator) {
    generator = DH_GENERATOR;
  } else if (typeof generator === 'number') {
    validateInt32(generator, 'generator');
  } else if (typeof generator === 'string') {
    generator = toBuf(generator, genEncoding);
  } else if (!isArrayBufferView(generator) && !isAnyArrayBuffer(generator)) {
    throw new ERR_INVALID_ARG_TYPE(
      'generator',
      ['number', 'string', 'ArrayBuffer', 'Buffer', 'TypedArray', 'DataView'],
      generator,
    );
  }


  this[kHandle] = new _DiffieHellman(sizeOrKey, generator);
  ObjectDefineProperty(this, 'verifyError', {
    __proto__: null,
    enumerable: true,
    value: this[kHandle].verifyError,
    writable: false,
  });
}