byteorder.BEUint64(H[:8]), byteorder.BEUint64(H[8:]), } productTable[reverseBits(1)] = x for i := 2; i < 16; i += 2 { productTable[reverseBits(i)] = ghashDouble(&productTable[reverseBits(i/2)]) productTable[reverseBits(i+1)] = ghashAdd(&productTable[reverseBits(i)], &x) } var y gcmFieldElement for _, input := range inputs { ghashUpdate(&productTable, &y, input) } byteorder.BEPutUint64(out[:], y.low) byteorder.BEPutUint64(out[8:], y.high) } // reverseBits reverses the order of the bits of 4-bit number in i. func...