Function gf128_mul4b

freebsd/opencrypto/gfmult.c:258–275

* a = data[0..15] + r * b = data[16..31] * c = data[32..47] * d = data[48..63] * * Calculate a*h^4 + b*h^3 + c*h^2 + d*h, or: * (((a*h+b)*h+c)*h+d)*h */

 * (((a*h+b)*h+c)*h+d)*h
 */
struct gf128
gf128_mul4b(struct gf128 r, const uint8_t *v, struct gf128table4 *tbl)
{
	struct gf128 a, b, c, d;
	struct gf128 tmp;

	tmp = MAKE_GF128(0, 0);

	a = gf128_add(r, gf128_read(&v[0*16]));
	b = gf128_read(&v[1*16]);
	c = gf128_read(&v[2*16]);
	d = gf128_read(&v[3*16]);

	tmp = gfmultword4(a.v[1], b.v[1], c.v[1], d.v[1], tmp, tbl);
	tmp = gfmultword4(a.v[0], b.v[0], c.v[0], d.v[0], tmp, tbl);

	return tmp;
}