GitBucket
Newer
#if !BESTHTTP_DISABLE_ALTERNATE_SSL && (!UNITY_WEBGL || UNITY_EDITOR)
#pragma warning disable
using System;
using System.Diagnostics;
namespace BestHTTP.SecureProtocol.Org.BouncyCastle.Math.EC.Rfc7748
{
public abstract class X25519Field
{
public const int Size = 10;
private const int M24 = 0x00FFFFFF;
private const int M25 = 0x01FFFFFF;
private const int M26 = 0x03FFFFFF;
private static readonly int[] RootNegOne = { 0x020EA0B0, 0x0386C9D2, 0x00478C4E, 0x0035697F, 0x005E8630,
0x01FBD7A7, 0x0340264F, 0x01F0B2B4, 0x00027E0E, 0x00570649 };
protected X25519Field() {}
public static void Add(int[] x, int[] y, int[] z)
{
for (int i = 0; i < Size; ++i)
{
z[i] = x[i] + y[i];
}
}
public static void AddOne(int[] z)
{
z[0] += 1;
}
public static void AddOne(int[] z, int zOff)
{
z[zOff] += 1;
}
public static void Apm(int[] x, int[] y, int[] zp, int[] zm)
{
for (int i = 0; i < Size; ++i)
{
int xi = x[i], yi = y[i];
zp[i] = xi + yi;
zm[i] = xi - yi;
}
}
public static void Carry(int[] z)
{
int z0 = z[0], z1 = z[1], z2 = z[2], z3 = z[3], z4 = z[4];
int z5 = z[5], z6 = z[6], z7 = z[7], z8 = z[8], z9 = z[9];
z3 += (z2 >> 25); z2 &= M25;
z5 += (z4 >> 25); z4 &= M25;
z8 += (z7 >> 25); z7 &= M25;
//z0 += (z9 >> 24) * 19; z9 &= M24;
z0 += (z9 >> 25) * 38; z9 &= M25;
z1 += (z0 >> 26); z0 &= M26;
z6 += (z5 >> 26); z5 &= M26;
z2 += (z1 >> 26); z1 &= M26;
z4 += (z3 >> 26); z3 &= M26;
z7 += (z6 >> 26); z6 &= M26;
z9 += (z8 >> 26); z8 &= M26;
z[0] = z0; z[1] = z1; z[2] = z2; z[3] = z3; z[4] = z4;
z[5] = z5; z[6] = z6; z[7] = z7; z[8] = z8; z[9] = z9;
}
public static void CMov(int cond, int[] x, int xOff, int[] z, int zOff)
{
Debug.Assert(0 == cond || -1 == cond);
for (int i = 0; i < Size; ++i)
{
int z_i = z[zOff + i], diff = z_i ^ x[xOff + i];
z_i ^= (diff & cond);
z[zOff + i] = z_i;
}
}
public static void CNegate(int negate, int[] z)
{
Debug.Assert(negate >> 1 == 0);
int mask = 0 - negate;
for (int i = 0; i < Size; ++i)
{
z[i] = (z[i] ^ mask) - mask;
}
}
public static void Copy(int[] x, int xOff, int[] z, int zOff)
{
for (int i = 0; i < Size; ++i)
{
z[zOff + i] = x[xOff + i];
}
}
public static int[] Create()
{
return new int[Size];
}
public static int[] CreateTable(int n)
{
return new int[Size * n];
}
public static void CSwap(int swap, int[] a, int[] b)
{
Debug.Assert(swap >> 1 == 0);
Debug.Assert(a != b);
int mask = 0 - swap;
for (int i = 0; i < Size; ++i)
{
int ai = a[i], bi = b[i];
int dummy = mask & (ai ^ bi);
a[i] = ai ^ dummy;
b[i] = bi ^ dummy;
}
}
public static void Decode(byte[] x, int xOff, int[] z)
{
Decode128(x, xOff, z, 0);
Decode128(x, xOff + 16, z, 5);
z[9] &= M24;
}
private static void Decode128(byte[] bs, int off, int[] z, int zOff)
{
uint t0 = Decode32(bs, off + 0);
uint t1 = Decode32(bs, off + 4);
uint t2 = Decode32(bs, off + 8);
uint t3 = Decode32(bs, off + 12);
z[zOff + 0] = (int)t0 & M26;
z[zOff + 1] = (int)((t1 << 6) | (t0 >> 26)) & M26;
z[zOff + 2] = (int)((t2 << 12) | (t1 >> 20)) & M25;
z[zOff + 3] = (int)((t3 << 19) | (t2 >> 13)) & M26;
z[zOff + 4] = (int)(t3 >> 7);
}
private static uint Decode32(byte[] bs, int off)
{
uint n = bs[off];
n |= (uint)bs[++off] << 8;
n |= (uint)bs[++off] << 16;
n |= (uint)bs[++off] << 24;
return n;
}
public static void Encode(int[] x, byte[] z, int zOff)
{
Encode128(x, 0, z, zOff);
Encode128(x, 5, z, zOff + 16);
}
private static void Encode128(int[] x, int xOff, byte[] bs, int off)
{
uint x0 = (uint)x[xOff + 0], x1 = (uint)x[xOff + 1], x2 = (uint)x[xOff + 2];
uint x3 = (uint)x[xOff + 3], x4 = (uint)x[xOff + 4];
uint t0 = x0 | (x1 << 26); Encode32(t0, bs, off + 0);
uint t1 = (x1 >> 6) | (x2 << 20); Encode32(t1, bs, off + 4);
uint t2 = (x2 >> 12) | (x3 << 13); Encode32(t2, bs, off + 8);
uint t3 = (x3 >> 19) | (x4 << 7); Encode32(t3, bs, off + 12);
}
private static void Encode32(uint n, byte[] bs, int off)
{
bs[ off] = (byte)(n );
bs[++off] = (byte)(n >> 8);
bs[++off] = (byte)(n >> 16);
bs[++off] = (byte)(n >> 24);
}
public static void Inv(int[] x, int[] z)
{
// z = x^(p-2) = x^7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEB
// (250 1s) (1 0s) (1 1s) (1 0s) (2 1s)
// Addition chain: [1] [2] 3 5 10 15 25 50 75 125 [250]
int[] x2 = Create();
int[] t = Create();
PowPm5d8(x, x2, t);
Sqr(t, 3, t);
Mul(t, x2, z);
}
public static int IsZero(int[] x)
{
int d = 0;
for (int i = 0; i < Size; ++i)
{
d |= x[i];
}
d |= d >> 16;
d &= 0xFFFF;
return (d - 1) >> 31;
}
public static bool IsZeroVar(int[] x)
{
return 0 != IsZero(x);
}
public static void Mul(int[] x, int y, int[] z)
{
int x0 = x[0], x1 = x[1], x2 = x[2], x3 = x[3], x4 = x[4];
int x5 = x[5], x6 = x[6], x7 = x[7], x8 = x[8], x9 = x[9];
long c0, c1, c2, c3;
c0 = (long)x2 * y; x2 = (int)c0 & M25; c0 >>= 25;
c1 = (long)x4 * y; x4 = (int)c1 & M25; c1 >>= 25;
c2 = (long)x7 * y; x7 = (int)c2 & M25; c2 >>= 25;
//c3 = (long)x9 * y; x9 = (int)c3 & M24; c3 >>= 24;
//c3 *= 19;
c3 = (long)x9 * y; x9 = (int)c3 & M25; c3 >>= 25;
c3 *= 38;
c3 += (long)x0 * y; z[0] = (int)c3 & M26; c3 >>= 26;
c1 += (long)x5 * y; z[5] = (int)c1 & M26; c1 >>= 26;
c3 += (long)x1 * y; z[1] = (int)c3 & M26; c3 >>= 26;
c0 += (long)x3 * y; z[3] = (int)c0 & M26; c0 >>= 26;
c1 += (long)x6 * y; z[6] = (int)c1 & M26; c1 >>= 26;
c2 += (long)x8 * y; z[8] = (int)c2 & M26; c2 >>= 26;
z[2] = x2 + (int)c3;
z[4] = x4 + (int)c0;
z[7] = x7 + (int)c1;
z[9] = x9 + (int)c2;
}
public static void Mul(int[] x, int[] y, int[] z)
{
int x0 = x[0], y0 = y[0];
int x1 = x[1], y1 = y[1];
int x2 = x[2], y2 = y[2];
int x3 = x[3], y3 = y[3];
int x4 = x[4], y4 = y[4];
int u0 = x[5], v0 = y[5];
int u1 = x[6], v1 = y[6];
int u2 = x[7], v2 = y[7];
int u3 = x[8], v3 = y[8];
int u4 = x[9], v4 = y[9];
long a0 = (long)x0 * y0;
long a1 = (long)x0 * y1
+ (long)x1 * y0;
long a2 = (long)x0 * y2
+ (long)x1 * y1
+ (long)x2 * y0;
long a3 = (long)x1 * y2
+ (long)x2 * y1;
a3 <<= 1;
a3 += (long)x0 * y3
+ (long)x3 * y0;
long a4 = (long)x2 * y2;
a4 <<= 1;
a4 += (long)x0 * y4
+ (long)x1 * y3
+ (long)x3 * y1
+ (long)x4 * y0;
long a5 = (long)x1 * y4
+ (long)x2 * y3
+ (long)x3 * y2
+ (long)x4 * y1;
a5 <<= 1;
long a6 = (long)x2 * y4
+ (long)x4 * y2;
a6 <<= 1;
a6 += (long)x3 * y3;
long a7 = (long)x3 * y4
+ (long)x4 * y3;
long a8 = (long)x4 * y4;
a8 <<= 1;
long b0 = (long)u0 * v0;
long b1 = (long)u0 * v1
+ (long)u1 * v0;
long b2 = (long)u0 * v2
+ (long)u1 * v1
+ (long)u2 * v0;
long b3 = (long)u1 * v2
+ (long)u2 * v1;
b3 <<= 1;
b3 += (long)u0 * v3
+ (long)u3 * v0;
long b4 = (long)u2 * v2;
b4 <<= 1;
b4 += (long)u0 * v4
+ (long)u1 * v3
+ (long)u3 * v1
+ (long)u4 * v0;
long b5 = (long)u1 * v4
+ (long)u2 * v3
+ (long)u3 * v2
+ (long)u4 * v1;
//b5 <<= 1;
long b6 = (long)u2 * v4
+ (long)u4 * v2;
b6 <<= 1;
b6 += (long)u3 * v3;
long b7 = (long)u3 * v4
+ (long)u4 * v3;
long b8 = (long)u4 * v4;
//b8 <<= 1;
a0 -= b5 * 76;
a1 -= b6 * 38;
a2 -= b7 * 38;
a3 -= b8 * 76;
a5 -= b0;
a6 -= b1;
a7 -= b2;
a8 -= b3;
//long a9 = -b4;
x0 += u0; y0 += v0;
x1 += u1; y1 += v1;
x2 += u2; y2 += v2;
x3 += u3; y3 += v3;
x4 += u4; y4 += v4;
long c0 = (long)x0 * y0;
long c1 = (long)x0 * y1
+ (long)x1 * y0;
long c2 = (long)x0 * y2
+ (long)x1 * y1
+ (long)x2 * y0;
long c3 = (long)x1 * y2
+ (long)x2 * y1;
c3 <<= 1;
c3 += (long)x0 * y3
+ (long)x3 * y0;
long c4 = (long)x2 * y2;
c4 <<= 1;
c4 += (long)x0 * y4
+ (long)x1 * y3
+ (long)x3 * y1
+ (long)x4 * y0;
long c5 = (long)x1 * y4
+ (long)x2 * y3
+ (long)x3 * y2
+ (long)x4 * y1;
c5 <<= 1;
long c6 = (long)x2 * y4
+ (long)x4 * y2;
c6 <<= 1;
c6 += (long)x3 * y3;
long c7 = (long)x3 * y4
+ (long)x4 * y3;
long c8 = (long)x4 * y4;
c8 <<= 1;
int z8, z9;
long t;
t = a8 + (c3 - a3);
z8 = (int)t & M26; t >>= 26;
//t += a9 + (c4 - a4);
t += (c4 - a4) - b4;
//z9 = (int)t & M24; t >>= 24;
//t = a0 + (t + ((c5 - a5) << 1)) * 19;
z9 = (int)t & M25; t >>= 25;
t = a0 + (t + c5 - a5) * 38;
z[0] = (int)t & M26; t >>= 26;
t += a1 + (c6 - a6) * 38;
z[1] = (int)t & M26; t >>= 26;
t += a2 + (c7 - a7) * 38;
z[2] = (int)t & M25; t >>= 25;
t += a3 + (c8 - a8) * 38;
z[3] = (int)t & M26; t >>= 26;
//t += a4 - a9 * 38;
t += a4 + b4 * 38;
z[4] = (int)t & M25; t >>= 25;
t += a5 + (c0 - a0);
z[5] = (int)t & M26; t >>= 26;
t += a6 + (c1 - a1);
z[6] = (int)t & M26; t >>= 26;
t += a7 + (c2 - a2);
z[7] = (int)t & M25; t >>= 25;
t += z8;
z[8] = (int)t & M26; t >>= 26;
z[9] = z9 + (int)t;
}
public static void Negate(int[] x, int[] z)
{
for (int i = 0; i < Size; ++i)
{
z[i] = -x[i];
}
}
public static void Normalize(int[] z)
{
int x = (z[9] >> 23) & 1;
Reduce(z, x);
Reduce(z, -x);
Debug.Assert(z[9] >> 24 == 0);
}
public static void One(int[] z)
{
z[0] = 1;
for (int i = 1; i < Size; ++i)
{
z[i] = 0;
}
}
private static void PowPm5d8(int[] x, int[] rx2, int[] rz)
{
// z = x^((p-5)/8) = x^FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFD
// (250 1s) (1 0s) (1 1s)
// Addition chain: [1] 2 3 5 10 15 25 50 75 125 [250]
int[] x2 = rx2; Sqr(x, x2); Mul(x, x2, x2);
int[] x3 = Create(); Sqr(x2, x3); Mul(x, x3, x3);
int[] x5 = x3; Sqr(x3, 2, x5); Mul(x2, x5, x5);
int[] x10 = Create(); Sqr(x5, 5, x10); Mul(x5, x10, x10);
int[] x15 = Create(); Sqr(x10, 5, x15); Mul(x5, x15, x15);
int[] x25 = x5; Sqr(x15, 10, x25); Mul(x10, x25, x25);
int[] x50 = x10; Sqr(x25, 25, x50); Mul(x25, x50, x50);
int[] x75 = x15; Sqr(x50, 25, x75); Mul(x25, x75, x75);
int[] x125 = x25; Sqr(x75, 50, x125); Mul(x50, x125, x125);
int[] x250 = x50; Sqr(x125, 125, x250); Mul(x125, x250, x250);
int[] t = x125;
Sqr(x250, 2, t);
Mul(t, x, rz);
}
private static void Reduce(int[] z, int c)
{
int z9 = z[9], t = z9;
z9 = t & M24; t >>= 24;
t += c;
t *= 19;
t += z[0]; z[0] = t & M26; t >>= 26;
t += z[1]; z[1] = t & M26; t >>= 26;
t += z[2]; z[2] = t & M25; t >>= 25;
t += z[3]; z[3] = t & M26; t >>= 26;
t += z[4]; z[4] = t & M25; t >>= 25;
t += z[5]; z[5] = t & M26; t >>= 26;
t += z[6]; z[6] = t & M26; t >>= 26;
t += z[7]; z[7] = t & M25; t >>= 25;
t += z[8]; z[8] = t & M26; t >>= 26;
t += z9; z[9] = t;
}
public static void Sqr(int[] x, int[] z)
{
int x0 = x[0];
int x1 = x[1];
int x2 = x[2];
int x3 = x[3];
int x4 = x[4];
int u0 = x[5];
int u1 = x[6];
int u2 = x[7];
int u3 = x[8];
int u4 = x[9];
int x1_2 = x1 * 2;
int x2_2 = x2 * 2;
int x3_2 = x3 * 2;
int x4_2 = x4 * 2;
long a0 = (long)x0 * x0;
long a1 = (long)x0 * x1_2;
long a2 = (long)x0 * x2_2
+ (long)x1 * x1;
long a3 = (long)x1_2 * x2_2
+ (long)x0 * x3_2;
long a4 = (long)x2 * x2_2
+ (long)x0 * x4_2
+ (long)x1 * x3_2;
long a5 = (long)x1_2 * x4_2
+ (long)x2_2 * x3_2;
long a6 = (long)x2_2 * x4_2
+ (long)x3 * x3;
long a7 = (long)x3 * x4_2;
long a8 = (long)x4 * x4_2;
int u1_2 = u1 * 2;
int u2_2 = u2 * 2;
int u3_2 = u3 * 2;
int u4_2 = u4 * 2;
long b0 = (long)u0 * u0;
long b1 = (long)u0 * u1_2;
long b2 = (long)u0 * u2_2
+ (long)u1 * u1;
long b3 = (long)u1_2 * u2_2
+ (long)u0 * u3_2;
long b4 = (long)u2 * u2_2
+ (long)u0 * u4_2
+ (long)u1 * u3_2;
long b5 = (long)u1_2 * u4_2
+ (long)u2_2 * u3_2;
long b6 = (long)u2_2 * u4_2
+ (long)u3 * u3;
long b7 = (long)u3 * u4_2;
long b8 = (long)u4 * u4_2;
a0 -= b5 * 38;
a1 -= b6 * 38;
a2 -= b7 * 38;
a3 -= b8 * 38;
a5 -= b0;
a6 -= b1;
a7 -= b2;
a8 -= b3;
//long a9 = -b4;
x0 += u0;
x1 += u1;
x2 += u2;
x3 += u3;
x4 += u4;
x1_2 = x1 * 2;
x2_2 = x2 * 2;
x3_2 = x3 * 2;
x4_2 = x4 * 2;
long c0 = (long)x0 * x0;
long c1 = (long)x0 * x1_2;
long c2 = (long)x0 * x2_2
+ (long)x1 * x1;
long c3 = (long)x1_2 * x2_2
+ (long)x0 * x3_2;
long c4 = (long)x2 * x2_2
+ (long)x0 * x4_2
+ (long)x1 * x3_2;
long c5 = (long)x1_2 * x4_2
+ (long)x2_2 * x3_2;
long c6 = (long)x2_2 * x4_2
+ (long)x3 * x3;
long c7 = (long)x3 * x4_2;
long c8 = (long)x4 * x4_2;
int z8, z9;
long t;
t = a8 + (c3 - a3);
z8 = (int)t & M26; t >>= 26;
//t += a9 + (c4 - a4);
t += (c4 - a4) - b4;
//z9 = (int)t & M24; t >>= 24;
//t = a0 + (t + ((c5 - a5) << 1)) * 19;
z9 = (int)t & M25; t >>= 25;
t = a0 + (t + c5 - a5) * 38;
z[0] = (int)t & M26; t >>= 26;
t += a1 + (c6 - a6) * 38;
z[1] = (int)t & M26; t >>= 26;
t += a2 + (c7 - a7) * 38;
z[2] = (int)t & M25; t >>= 25;
t += a3 + (c8 - a8) * 38;
z[3] = (int)t & M26; t >>= 26;
//t += a4 - a9 * 38;
t += a4 + b4 * 38;
z[4] = (int)t & M25; t >>= 25;
t += a5 + (c0 - a0);
z[5] = (int)t & M26; t >>= 26;
t += a6 + (c1 - a1);
z[6] = (int)t & M26; t >>= 26;
t += a7 + (c2 - a2);
z[7] = (int)t & M25; t >>= 25;
t += z8;
z[8] = (int)t & M26; t >>= 26;
z[9] = z9 + (int)t;
}
public static void Sqr(int[] x, int n, int[] z)
{
Debug.Assert(n > 0);
Sqr(x, z);
while (--n > 0)
{
Sqr(z, z);
}
}
public static bool SqrtRatioVar(int[] u, int[] v, int[] z)
{
int[] uv3 = Create();
int[] uv7 = Create();
Mul(u, v, uv3);
Sqr(v, uv7);
Mul(uv3, uv7, uv3);
Sqr(uv7, uv7);
Mul(uv7, uv3, uv7);
int[] t = Create();
int[] x = Create();
PowPm5d8(uv7, t, x);
Mul(x, uv3, x);
int[] vx2 = Create();
Sqr(x, vx2);
Mul(vx2, v, vx2);
Sub(vx2, u, t);
Normalize(t);
if (IsZeroVar(t))
{
Copy(x, 0, z, 0);
return true;
}
Add(vx2, u, t);
Normalize(t);
if (IsZeroVar(t))
{
Mul(x, RootNegOne, z);
return true;
}
return false;
}
public static void Sub(int[] x, int[] y, int[] z)
{
for (int i = 0; i < Size; ++i)
{
z[i] = x[i] - y[i];
}
}
public static void SubOne(int[] z)
{
z[0] -= 1;
}
public static void Zero(int[] z)
{
for (int i = 0; i < Size; ++i)
{
z[i] = 0;
}
}
}
}
#pragma warning restore
#endif