code: function _rsasign_getDecryptSignatureBI(biSig, hN, hE) {
      var rsa = new RSAKey();
      rsa.setPublic(hN, hE);
      var biDecryptedSig = rsa.doPublic(biSig);
      return biDecryptedSig;
  }
docs: ======================================================================== Signature Verification ========================================================================