package org.bouncycastle.math.ec.custom.sec; import java.math.BigInteger; import org.bouncycastle.math.raw.Interleave; import org.bouncycastle.math.raw.Nat; import org.bouncycastle.math.raw.Nat576; public class SecT571Field { private static final long M59 = -1L >>> 5; private static final long RM = 0xEF7BDEF7BDEF7BDEL; private static final long[] ROOT_Z = new long[]{ 0x2BE1195F08CAFB99L, 0x95F08CAF84657C23L, 0xCAF84657C232BE11L, 0x657C232BE1195F08L, 0xF84657C2308CAF84L, 0x7C232BE1195F08CAL, 0xBE1195F08CAF8465L, 0x5F08CAF84657C232L, 0x784657C232BE119L }; public static void add(long[] x, long[] y, long[] z) { for (int i = 0; i < 9; ++i) { z[i] = x[i] ^ y[i]; } } private static void add(long[] x, int xOff, long[] y, int yOff, long[] z, int zOff) { for (int i = 0; i < 9; ++i) { z[zOff + i] = x[xOff + i] ^ y[yOff + i]; } } public static void addBothTo(long[] x, long[] y, long[] z) { for (int i = 0; i < 9; ++i) { z[i] ^= x[i] ^ y[i]; } } private static void addBothTo(long[] x, int xOff, long[] y, int yOff, long[] z, int zOff) { for (int i = 0; i < 9; ++i) { z[zOff + i] ^= x[xOff + i] ^ y[yOff + i]; } } public static void addExt(long[] xx, long[] yy, long[] zz) { for (int i = 0; i < 18; ++i) { zz[i] = xx[i] ^ yy[i]; } } public static void addOne(long[] x, long[] z) { z[0] = x[0] ^ 1L; for (int i = 1; i < 9; ++i) { z[i] = x[i]; } } public static long[] fromBigInteger(BigInteger x) { long[] z = Nat576.fromBigInteger64(x); reduce5(z, 0); return z; } public static void invert(long[] x, long[] z) { if (Nat576.isZero64(x)) { throw new IllegalStateException(); } // Itoh-Tsujii inversion with bases { 2, 3, 5 } long[] t0 = Nat576.create64(); long[] t1 = Nat576.create64(); long[] t2 = Nat576.create64(); square(x, t2); // 5 | 570 square(t2, t0); square(t0, t1); multiply(t0, t1, t0); squareN(t0, 2, t1); multiply(t0, t1, t0); multiply(t0, t2, t0); // 3 | 114 squareN(t0, 5, t1); multiply(t0, t1, t0); squareN(t1, 5, t1); multiply(t0, t1, t0); // 2 | 38 squareN(t0, 15, t1); multiply(t0, t1, t2); // ! {2,3,5} | 19 squareN(t2, 30, t0); squareN(t0, 30, t1); multiply(t0, t1, t0); // 3 | 9 squareN(t0, 60, t1); multiply(t0, t1, t0); squareN(t1, 60, t1); multiply(t0, t1, t0); // 3 | 3 squareN(t0, 180, t1); multiply(t0, t1, t0); squareN(t1, 180, t1); multiply(t0, t1, t0); multiply(t0, t2, z); } public static void multiply(long[] x, long[] y, long[] z) { long[] tt = Nat576.createExt64(); implMultiply(x, y, tt); reduce(tt, z); } public static void multiplyAddToExt(long[] x, long[] y, long[] zz) { long[] tt = Nat576.createExt64(); implMultiply(x, y, tt); addExt(zz, tt, zz); } public static void multiplyPrecomp(long[] x, long[] precomp, long[] z) { long[] tt = Nat576.createExt64(); implMultiplyPrecomp(x, precomp, tt); reduce(tt, z); } public static void multiplyPrecompAddToExt(long[] x, long[] precomp, long[] zz) { long[] tt = Nat576.createExt64(); implMultiplyPrecomp(x, precomp, tt); addExt(zz, tt, zz); } public static long[] precompMultiplicand(long[] x) { /* * Precompute table of all 4-bit products of x (first section) */ int len = 9 << 4; long[] t = new long[len << 1]; System.arraycopy(x, 0, t, 9, 9); // reduce5(T0, 9); int tOff = 0; for (int i = 7; i > 0; --i) { tOff += 18; Nat.shiftUpBit64(9, t, tOff >>> 1, 0L, t, tOff); reduce5(t, tOff); add(t, 9, t, tOff, t, tOff + 9); } /* * Second section with all 4-bit products of B shifted 4 bits */ Nat.shiftUpBits64(len, t, 0, 4, 0L, t, len); return t; } public static void reduce(long[] xx, long[] z) { long xx09 = xx[9]; long u = xx[17], v = xx09; xx09 = v ^ (u >>> 59) ^ (u >>> 57) ^ (u >>> 54) ^ (u >>> 49); v = xx[8] ^ (u << 5) ^ (u << 7) ^ (u << 10) ^ (u << 15); for (int i = 16; i >= 10; --i) { u = xx[i]; z[i - 8] = v ^ (u >>> 59) ^ (u >>> 57) ^ (u >>> 54) ^ (u >>> 49); v = xx[i - 9] ^ (u << 5) ^ (u << 7) ^ (u << 10) ^ (u << 15); } u = xx09; z[1] = v ^ (u >>> 59) ^ (u >>> 57) ^ (u >>> 54) ^ (u >>> 49); v = xx[0] ^ (u << 5) ^ (u << 7) ^ (u << 10) ^ (u << 15); long x08 = z[8]; long t = x08 >>> 59; z[0] = v ^ t ^ (t << 2) ^ (t << 5) ^ (t << 10); z[8] = x08 & M59; } public static void reduce5(long[] z, int zOff) { long z8 = z[zOff + 8], t = z8 >>> 59; z[zOff ] ^= t ^ (t << 2) ^ (t << 5) ^ (t << 10); z[zOff + 8] = z8 & M59; } public static void sqrt(long[] x, long[] z) { long[] evn = Nat576.create64(), odd = Nat576.create64(); int pos = 0; for (int i = 0; i < 4; ++i) { long u0 = Interleave.unshuffle(x[pos++]); long u1 = Interleave.unshuffle(x[pos++]); evn[i] = (u0 & 0x00000000FFFFFFFFL) | (u1 << 32); odd[i] = (u0 >>> 32) | (u1 & 0xFFFFFFFF00000000L); } { long u0 = Interleave.unshuffle(x[pos]); evn[4] = (u0 & 0x00000000FFFFFFFFL); odd[4] = (u0 >>> 32); } multiply(odd, ROOT_Z, z); add(z, evn, z); } public static void square(long[] x, long[] z) { long[] tt = Nat576.createExt64(); implSquare(x, tt); reduce(tt, z); } public static void squareAddToExt(long[] x, long[] zz) { long[] tt = Nat576.createExt64(); implSquare(x, tt); addExt(zz, tt, zz); } public static void squareN(long[] x, int n, long[] z) { // assert n > 0; long[] tt = Nat576.createExt64(); implSquare(x, tt); reduce(tt, z); while (--n > 0) { implSquare(z, tt); reduce(tt, z); } } public static int trace(long[] x) { // Non-zero-trace bits: 0, 561, 569 return (int)(x[0] ^ (x[8] >>> 49) ^ (x[8] >>> 57)) & 1; } protected static void implMultiply(long[] x, long[] y, long[] zz) { // for (int i = 0; i < 9; ++i) // { // implMulwAcc(x, y[i], zz, i); // } long[] precomp = precompMultiplicand(y); implMultiplyPrecomp(x, precomp, zz); } protected static void implMultiplyPrecomp(long[] x, long[] precomp, long[] zz) { int MASK = 0xF; /* * Lopez-Dahab algorithm */ for (int k = 56; k >= 0; k -= 8) { for (int j = 1; j < 9; j += 2) { int aVal = (int)(x[j] >>> k); int u = aVal & MASK; int v = (aVal >>> 4) & MASK; addBothTo(precomp, 9 * u, precomp, 9 * (v + 16), zz, j - 1); } Nat.shiftUpBits64(16, zz, 0, 8, 0L); } for (int k = 56; k >= 0; k -= 8) { for (int j = 0; j < 9; j += 2) { int aVal = (int)(x[j] >>> k); int u = aVal & MASK; int v = (aVal >>> 4) & MASK; addBothTo(precomp, 9 * u, precomp, 9 * (v + 16), zz, j); } if (k > 0) { Nat.shiftUpBits64(18, zz, 0, 8, 0L); } } } protected static void implMulwAcc(long[] xs, long y, long[] z, int zOff) { long[] u = new long[32]; // u[0] = 0; u[1] = y; for (int i = 2; i < 32; i += 2) { u[i ] = u[i >>> 1] << 1; u[i + 1] = u[i ] ^ y; } long l = 0; for (int i = 0; i < 9; ++i) { long x = xs[i]; int j = (int)x; l ^= u[j & 31]; long g, h = 0; int k = 60; do { j = (int)(x >>> k); g = u[j & 31]; l ^= (g << k); h ^= (g >>> -k); } while ((k -= 5) > 0); for (int p = 0; p < 4; ++p) { x = (x & RM) >>> 1; h ^= x & ((y << p) >> 63); } z[zOff + i] ^= l; l = h; } z[zOff + 9] ^= l; } protected static void implSquare(long[] x, long[] zz) { for (int i = 0; i < 9; ++i) { Interleave.expand64To128(x[i], zz, i << 1); } } }