org.bouncycastle.pqc.crypto.crystals.kyber.Ntt Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of bcprov-jdk14 Show documentation
Show all versions of bcprov-jdk14 Show documentation
The Bouncy Castle Crypto package is a Java implementation of cryptographic algorithms. This jar contains JCE provider and lightweight API for the Bouncy Castle Cryptography APIs for JDK 1.4.
package org.bouncycastle.pqc.crypto.crystals.kyber;
class Ntt
{
public static final short[] nttZetas = new short[]{
2285, 2571, 2970, 1812, 1493, 1422, 287, 202, 3158, 622, 1577, 182, 962,
2127, 1855, 1468, 573, 2004, 264, 383, 2500, 1458, 1727, 3199, 2648, 1017,
732, 608, 1787, 411, 3124, 1758, 1223, 652, 2777, 1015, 2036, 1491, 3047,
1785, 516, 3321, 3009, 2663, 1711, 2167, 126, 1469, 2476, 3239, 3058, 830,
107, 1908, 3082, 2378, 2931, 961, 1821, 2604, 448, 2264, 677, 2054, 2226,
430, 555, 843, 2078, 871, 1550, 105, 422, 587, 177, 3094, 3038, 2869, 1574,
1653, 3083, 778, 1159, 3182, 2552, 1483, 2727, 1119, 1739, 644, 2457, 349,
418, 329, 3173, 3254, 817, 1097, 603, 610, 1322, 2044, 1864, 384, 2114, 3193,
1218, 1994, 2455, 220, 2142, 1670, 2144, 1799, 2051, 794, 1819, 2475, 2459,
478, 3221, 3021, 996, 991, 958, 1869, 1522, 1628};
public static final short[] nttZetasInv = new short[]{
1701, 1807, 1460, 2371, 2338, 2333, 308, 108, 2851, 870, 854, 1510, 2535,
1278, 1530, 1185, 1659, 1187, 3109, 874, 1335, 2111, 136, 1215, 2945, 1465,
1285, 2007, 2719, 2726, 2232, 2512, 75, 156, 3000, 2911, 2980, 872, 2685,
1590, 2210, 602, 1846, 777, 147, 2170, 2551, 246, 1676, 1755, 460, 291, 235,
3152, 2742, 2907, 3224, 1779, 2458, 1251, 2486, 2774, 2899, 1103, 1275, 2652,
1065, 2881, 725, 1508, 2368, 398, 951, 247, 1421, 3222, 2499, 271, 90, 853,
1860, 3203, 1162, 1618, 666, 320, 8, 2813, 1544, 282, 1838, 1293, 2314, 552,
2677, 2106, 1571, 205, 2918, 1542, 2721, 2597, 2312, 681, 130, 1602, 1871,
829, 2946, 3065, 1325, 2756, 1861, 1474, 1202, 2367, 3147, 1752, 2707, 171,
3127, 3042, 1907, 1836, 1517, 359, 758, 1441};
public static short[] ntt(short[] inp)
{
short[] r = new short[KyberEngine.KyberN];
System.arraycopy(inp, 0, r, 0, r.length);
int len, start, j, k;
short t, zeta;
k = 1;
for (len = 128; len >= 2; len >>= 1)
{
for (start = 0; start < 256; start = j + len)
{
zeta = nttZetas[k++];
for (j = start; j < start + len; ++j)
{
t = factorQMulMont(zeta, r[j + len]);
r[j + len] = (short)(r[j] - t);
r[j] = (short)(r[j] + t);
}
}
}
return r;
}
public static short[] invNtt(short[] inp)
{
short[] r = new short[KyberEngine.KyberN];
System.arraycopy(inp, 0, r, 0, KyberEngine.KyberN);
int len, start, j, k;
short t, zeta;
k = 0;
for (len = 2; len <= 128; len <<= 1)
{
for (start = 0; start < 256; start = j + len)
{
zeta = nttZetasInv[k++];
for (j = start; j < start + len; ++j)
{
t = r[j];
r[j] = Reduce.barretReduce((short)(t + r[j + len]));
r[j + len] = (short)(t - r[j + len]);
r[j + len] = factorQMulMont(zeta, r[j + len]);
}
}
}
for (j = 0; j < 256; ++j)
{
r[j] = factorQMulMont(r[j], Ntt.nttZetasInv[127]);
}
return r;
}
public static short factorQMulMont(short a, short b)
{
return Reduce.montgomeryReduce((int)(a * b));
}
public static void baseMult(Poly outPoly, int outIndex, short a0, short a1, short b0, short b1, short zeta)
{
short outVal0 = factorQMulMont(a1, b1);
outVal0 = factorQMulMont(outVal0, zeta);
outVal0 += factorQMulMont(a0, b0);
outPoly.setCoeffIndex(outIndex, outVal0);
short outVal1 = factorQMulMont(a0, b1);
outVal1 += factorQMulMont(a1, b0);
outPoly.setCoeffIndex(outIndex + 1, outVal1);
}
}