function RIPEMD160 () {
  HashBase.call(this, 64)

  // state
  this._a = 0x67452301
  this._b = 0xefcdab89
  this._c = 0x98badcfe
  this._d = 0x10325476
  this._e = 0xc3d2e1f0
}
Called upon socket error.

@api private