private void fw(byte[] input)
{
Gost3411Digest.cpyBytesToShort(input, this.wS);
this.w_S[15] = (this.wS[0] ^ this.wS[1] ^ this.wS[2] ^ this.wS[3] ^ this.wS[12] ^ this.wS[15]);
Array.Copy(this.wS, 1, this.w_S, 0, 15);
Gost3411Digest.cpyShortToBytes(this.w_S, input);
}