| 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); |
| } |
| } |
| } |