1package org.bouncycastle.math.raw;
2
3
4public abstract class Nat512
5{
6    public static void mul(int[] x, int[] y, int[] zz)
7    {
8        Nat256.mul(x, y, zz);
9        Nat256.mul(x, 8, y, 8, zz, 16);
10
11        int c24 = Nat256.addToEachOther(zz, 8, zz, 16);
12        int c16 = c24 + Nat256.addTo(zz, 0, zz, 8, 0);
13        c24 += Nat256.addTo(zz, 24, zz, 16, c16);
14
15        int[] dx = Nat256.create(), dy = Nat256.create();
16        boolean neg = Nat256.diff(x, 8, x, 0, dx, 0) != Nat256.diff(y, 8, y, 0, dy, 0);
17
18        int[] tt = Nat256.createExt();
19        Nat256.mul(dx, dy, tt);
20
21        c24 += neg ? Nat.addTo(16, tt, 0, zz, 8) : Nat.subFrom(16, tt, 0, zz, 8);
22        Nat.addWordAt(32, c24, zz, 24);
23    }
24
25    public static void square(int[] x, int[] zz)
26    {
27        Nat256.square(x, zz);
28        Nat256.square(x, 8, zz, 16);
29
30        int c24 = Nat256.addToEachOther(zz, 8, zz, 16);
31        int c16 = c24 + Nat256.addTo(zz, 0, zz, 8, 0);
32        c24 += Nat256.addTo(zz, 24, zz, 16, c16);
33
34        int[] dx = Nat256.create();
35        Nat256.diff(x, 8, x, 0, dx, 0);
36
37        int[] tt = Nat256.createExt();
38        Nat256.square(dx, tt);
39
40        c24 += Nat.subFrom(16, tt, 0, zz, 8);
41        Nat.addWordAt(32, c24, zz, 24);
42    }
43}
44