diff --git a/crypto/src/math/ec/rfc7748/X25519.cs b/crypto/src/math/ec/rfc7748/X25519.cs
index 16f680d90..a10d53da5 100644
--- a/crypto/src/math/ec/rfc7748/X25519.cs
+++ b/crypto/src/math/ec/rfc7748/X25519.cs
@@ -10,10 +10,10 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
private const int C_A24 = (C_A + 2)/4;
// 0x1
- //private static readonly int[] S_x = new int[] { 1, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+ //private static readonly int[] S_x = { 1, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
// 0x215132111D8354CB52385F46DCA2B71D440F6A51EB4D1207816B1E0137D48290
- private static readonly int[] PsubS_x = new int[]{ 0x03D48290, 0x02C7804D, 0x01207816, 0x028F5A68, 0x00881ED4, 0x00A2B71D,
+ private static readonly int[] PsubS_x = { 0x03D48290, 0x02C7804D, 0x01207816, 0x028F5A68, 0x00881ED4, 0x00A2B71D,
0x0217D1B7, 0x014CB523, 0x0088EC1A, 0x0042A264 };
private static int[] precompBase = null;
diff --git a/crypto/src/math/ec/rfc7748/X25519Field.cs b/crypto/src/math/ec/rfc7748/X25519Field.cs
index 282f41628..fd5599657 100644
--- a/crypto/src/math/ec/rfc7748/X25519Field.cs
+++ b/crypto/src/math/ec/rfc7748/X25519Field.cs
@@ -11,6 +11,9 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
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 };
+
private X25519Field() {}
public static void Add(int[] x, int[] y, int[] z)
@@ -21,6 +24,16 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
}
}
+ 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)
@@ -54,6 +67,17 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
z[5] = z5; z[6] = z6; z[7] = z7; z[8] = z8; z[9] = z9;
}
+ 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)
@@ -67,6 +91,11 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
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);
@@ -143,24 +172,23 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
// (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(); 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, t);
+ int[] x2 = Create();
+ int[] t = Create();
+ PowPm5d8(x, x2, t);
Sqr(t, 3, t);
Mul(t, x2, z);
}
+ public static bool IsZeroVar(int[] x)
+ {
+ int d = 0;
+ for (int i = 0; i < Size; ++i)
+ {
+ d |= x[i];
+ }
+ return d == 0;
+ }
+
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];
@@ -345,6 +373,14 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
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;
@@ -353,6 +389,37 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
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;
@@ -509,6 +576,45 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
}
}
+ 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)
@@ -516,5 +622,18 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
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;
+ }
+ }
}
}
diff --git a/crypto/src/math/ec/rfc7748/X448.cs b/crypto/src/math/ec/rfc7748/X448.cs
index 32a4a9e2a..88e8a5d76 100644
--- a/crypto/src/math/ec/rfc7748/X448.cs
+++ b/crypto/src/math/ec/rfc7748/X448.cs
@@ -10,14 +10,14 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
private const uint C_A24 = (C_A + 2)/4;
// 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFE
- private static readonly uint[] S_x = new uint[]{ 0x0FFFFFFEU, 0x0FFFFFFFU, 0x0FFFFFFFU, 0x0FFFFFFFU, 0x0FFFFFFFU, 0x0FFFFFFFU,
+ private static readonly uint[] S_x = { 0x0FFFFFFEU, 0x0FFFFFFFU, 0x0FFFFFFFU, 0x0FFFFFFFU, 0x0FFFFFFFU, 0x0FFFFFFFU,
0x0FFFFFFFU, 0x0FFFFFFFU, 0x0FFFFFFEU, 0x0FFFFFFFU, 0x0FFFFFFFU, 0x0FFFFFFFU, 0x0FFFFFFFU, 0x0FFFFFFFU, 0x0FFFFFFFU,
0x0FFFFFFFU };
// 0xF0FAB725013244423ACF03881AFFEB7BDACDD1031C81B9672954459D84C1F823F1BD65643ACE1B5123AC33FF1C69BAF8ACB1197DC99D2720
- private static readonly uint[] PsubS_x = new uint[]{ 0x099d2720U, 0x0b1197dcU, 0x09baf8acU, 0x033ff1c6U, 0x0b5123acU,
- 0x0643ace1U, 0x03f1bd65U, 0x084c1f82U, 0x0954459dU, 0x081b9672U, 0x0dd1031cU, 0x0eb7bdacU, 0x03881affU, 0x0423acf0U,
- 0x05013244U, 0x0f0fab72U };
+ private static readonly uint[] PsubS_x = { 0x099D2720U, 0x0B1197DCU, 0x09BAF8ACU, 0x033FF1C6U, 0x0B5123ACU,
+ 0x0643ACE1U, 0x03F1BD65U, 0x084C1F82U, 0x0954459DU, 0x081B9672U, 0x0DD1031CU, 0x0EB7BDACU, 0x03881AFFU, 0x0423ACF0U,
+ 0x05013244U, 0x0F0FAB72U };
private static uint[] precompBase = null;
diff --git a/crypto/src/math/ec/rfc7748/X448Field.cs b/crypto/src/math/ec/rfc7748/X448Field.cs
index 0c44f1eb5..5a682714d 100644
--- a/crypto/src/math/ec/rfc7748/X448Field.cs
+++ b/crypto/src/math/ec/rfc7748/X448Field.cs
@@ -1,6 +1,8 @@
using System;
using System.Diagnostics;
+using Org.BouncyCastle.Math.Raw;
+
namespace Org.BouncyCastle.Math.EC.Rfc7748
{
[CLSCompliantAttribute(false)]
@@ -20,6 +22,16 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
}
}
+ public static void AddOne(uint[] z)
+ {
+ z[0] += 1;
+ }
+
+ public static void AddOne(uint[] 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)
@@ -62,6 +74,16 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
z[8] = z8; z[9] = z9; z[10] = z10; z[11] = z11; z[12] = z12; z[13] = z13; z[14] = z14; z[15] = z15;
}
+ public static void CNegate(int negate, uint[] z)
+ {
+ Debug.Assert(negate >> 1 == 0);
+
+ uint[] t = Create();
+ Sub(t, z, t);
+
+ Nat.CMov(Size, negate, t, 0, z, 0);
+ }
+
public static void Copy(uint[] x, int xOff, uint[] z, int zOff)
{
for (int i = 0; i < Size; ++i)
@@ -166,25 +188,23 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
// z = x^(p-2) = x^(2^448 - 2^224 - 3)
// (223 1s) (1 0s) (222 1s) (1 0s) (1 1s)
// Addition chain: [1] 2 3 6 9 18 19 37 74 111 [222] [223]
- uint[] x2 = Create(); Sqr(x, x2); Mul(x, x2, x2);
- uint[] x3 = Create(); Sqr(x2, x3); Mul(x, x3, x3);
- uint[] x6 = Create(); Sqr(x3, 3, x6); Mul(x3, x6, x6);
- uint[] x9 = Create(); Sqr(x6, 3, x9); Mul(x3, x9, x9);
- uint[] x18 = Create(); Sqr(x9, 9, x18); Mul(x9, x18, x18);
- uint[] x19 = Create(); Sqr(x18, x19); Mul(x, x19, x19);
- uint[] x37 = Create(); Sqr(x19, 18, x37); Mul(x18, x37, x37);
- uint[] x74 = Create(); Sqr(x37, 37, x74); Mul(x37, x74, x74);
- uint[] x111 = Create(); Sqr(x74, 37, x111); Mul(x37, x111, x111);
- uint[] x222 = Create(); Sqr(x111, 111, x222); Mul(x111, x222, x222);
- uint[] x223 = Create(); Sqr(x222, x223); Mul(x, x223, x223);
uint[] t = Create();
- Sqr(x223, 223, t);
- Mul(t, x222, t);
+ PowPm3d4(x, t);
Sqr(t, 2, t);
Mul(t, x, z);
}
+ public static bool IsZeroVar(uint[] x)
+ {
+ uint d = 0;
+ for (int i = 0; i < Size; ++i)
+ {
+ d |= x[i];
+ }
+ return d == 0U;
+ }
+
public static void Mul(uint[] x, uint y, uint[] z)
{
uint x0 = x[0], x1 = x[1], x2 = x[2], x3 = x[3], x4 = x[4], x5 = x[5], x6 = x[6], x7 = x[7];
@@ -563,6 +583,12 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
z[15] = z15;
}
+ public static void Negate(uint[] x, uint[] z)
+ {
+ uint[] zero = Create();
+ Sub(zero, x, z);
+ }
+
public static void Normalize(uint[] z)
{
//int x = (z[15] >> (28 - 1)) & 1;
@@ -571,6 +597,37 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
Debug.Assert(z[15] >> 28 == 0U);
}
+ public static void One(uint[] z)
+ {
+ z[0] = 1U;
+ for (int i = 1; i < Size; ++i)
+ {
+ z[i] = 0;
+ }
+ }
+
+ private static void PowPm3d4(uint[] x, uint[] z)
+ {
+ // z = x^((p-3)/4) = x^(2^446 - 2^222 - 1)
+ // (223 1s) (1 0s) (222 1s)
+ // Addition chain: 1 2 3 6 9 18 19 37 74 111 [222] [223]
+ uint[] x2 = Create(); Sqr(x, x2); Mul(x, x2, x2);
+ uint[] x3 = Create(); Sqr(x2, x3); Mul(x, x3, x3);
+ uint[] x6 = Create(); Sqr(x3, 3, x6); Mul(x3, x6, x6);
+ uint[] x9 = Create(); Sqr(x6, 3, x9); Mul(x3, x9, x9);
+ uint[] x18 = Create(); Sqr(x9, 9, x18); Mul(x9, x18, x18);
+ uint[] x19 = Create(); Sqr(x18, x19); Mul(x, x19, x19);
+ uint[] x37 = Create(); Sqr(x19, 18, x37); Mul(x18, x37, x37);
+ uint[] x74 = Create(); Sqr(x37, 37, x74); Mul(x37, x74, x74);
+ uint[] x111 = Create(); Sqr(x74, 37, x111); Mul(x37, x111, x111);
+ uint[] x222 = Create(); Sqr(x111, 111, x222); Mul(x111, x222, x222);
+ uint[] x223 = Create(); Sqr(x222, x223); Mul(x, x223, x223);
+
+ uint[] t = Create();
+ Sqr(x223, 223, t);
+ Mul(t, x222, z);
+ }
+
private static void Reduce(uint[] z, int c)
{
uint z15 = z[15];
@@ -836,6 +893,38 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
}
}
+ public static bool SqrtRatioVar(uint[] u, uint[] v, uint[] z)
+ {
+ uint[] u3v = Create();
+ uint[] u5v3 = Create();
+
+ Sqr(u, u3v);
+ Mul(u3v, v, u3v);
+ Sqr(u3v, u5v3);
+ Mul(u3v, u, u3v);
+ Mul(u5v3, u, u5v3);
+ Mul(u5v3, v, u5v3);
+
+ uint[] x = Create();
+ PowPm3d4(u5v3, x);
+ Mul(x, u3v, x);
+
+ uint[] t = Create();
+ Sqr(x, t);
+ Mul(t, v, t);
+
+ Sub(u, t, t);
+ Normalize(t);
+
+ if (IsZeroVar(t))
+ {
+ Copy(x, 0, z, 0);
+ return true;
+ }
+
+ return false;
+ }
+
public static void Sub(uint[] x, uint[] y, uint[] z)
{
uint x0 = x[0], x1 = x[1], x2 = x[2], x3 = x[3], x4 = x[4], x5 = x[5], x6 = x[6], x7 = x[7];
@@ -900,5 +989,13 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748
z[14] = z14;
z[15] = z15;
}
+
+ public static void Zero(uint[] z)
+ {
+ for (int i = 0; i < Size; ++i)
+ {
+ z[i] = 0;
+ }
+ }
}
}
diff --git a/crypto/src/math/ec/rfc8032/Ed25519.cs b/crypto/src/math/ec/rfc8032/Ed25519.cs
new file mode 100644
index 000000000..ff4587cb2
--- /dev/null
+++ b/crypto/src/math/ec/rfc8032/Ed25519.cs
@@ -0,0 +1,937 @@
+using System;
+using System.Diagnostics;
+using System.Runtime.CompilerServices;
+
+using Org.BouncyCastle.Crypto.Digests;
+using Org.BouncyCastle.Math.EC.Rfc7748;
+using Org.BouncyCastle.Math.Raw;
+using Org.BouncyCastle.Utilities;
+
+namespace Org.BouncyCastle.Math.EC.Rfc8032
+{
+ public abstract class Ed25519
+ {
+ private const long M28L = 0x0FFFFFFFL;
+ private const long M32L = 0xFFFFFFFFL;
+
+ private const int PointBytes = 32;
+ private const int ScalarUints = 8;
+ private const int ScalarBytes = ScalarUints * 4;
+
+ public static readonly int PublicKeySize = PointBytes;
+ public static readonly int SecretKeySize = 32;
+ public static readonly int SignatureSize = PointBytes + ScalarBytes;
+
+ //private static readonly byte[] Dom2Prefix = Strings.ToByteArray("SigEd25519 no Ed25519 collisions");
+
+ private static readonly uint[] P = { 0xFFFFFFEDU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0x7FFFFFFFU };
+ private static readonly uint[] L = { 0x5CF5D3EDU, 0x5812631AU, 0xA2F79CD6U, 0x14DEF9DEU, 0x00000000U, 0x00000000U, 0x00000000U, 0x10000000U };
+
+ private const int L0 = unchecked((int)0xFCF5D3ED); // L0:26/--
+ private const int L1 = 0x012631A6; // L1:24/22
+ private const int L2 = 0x079CD658; // L2:27/--
+ private const int L3 = unchecked((int)0xFF9DEA2F); // L3:23/--
+ private const int L4 = 0x000014DF; // L4:12/11
+
+ private static readonly int[] B_x = { 0x0325D51A, 0x018B5823, 0x007B2C95, 0x0304A92D, 0x00D2598E, 0x01D6DC5C,
+ 0x01388C7F, 0x013FEC0A, 0x029E6B72, 0x0042D26D };
+ private static readonly int[] B_y = { 0x02666658, 0x01999999, 0x00666666, 0x03333333, 0x00CCCCCC, 0x02666666,
+ 0x01999999, 0x00666666, 0x03333333, 0x00CCCCCC, };
+ private static readonly int[] C_d = { 0x035978A3, 0x02D37284, 0x018AB75E, 0x026A0A0E, 0x0000E014, 0x0379E898,
+ 0x01D01E5D, 0x01E738CC, 0x03715B7F, 0x00A406D9 };
+ private static readonly int[] C_d2 = { 0x02B2F159, 0x01A6E509, 0x01156EBD, 0x00D4141D, 0x0001C029, 0x02F3D130,
+ 0x03A03CBB, 0x01CE7198, 0x02E2B6FF, 0x00480DB3 };
+ private static readonly int[] C_d4 = { 0x0165E2B2, 0x034DCA13, 0x002ADD7A, 0x01A8283B, 0x00038052, 0x01E7A260,
+ 0x03407977, 0x019CE331, 0x01C56DFF, 0x00901B67 };
+
+ private const int WnafWidthBase = 7;
+
+ private const int PrecompBlocks = 8;
+ private const int PrecompTeeth = 4;
+ private const int PrecompSpacing = 8;
+ private const int PrecompPoints = 1 << (PrecompTeeth - 1);
+ private const int PrecompMask = PrecompPoints - 1;
+
+ // TODO[ed25519] Convert to PointPrecomp
+ private static PointExt[] precompBaseTable = null;
+ private static int[] precompBase = null;
+
+ private class PointAccum
+ {
+ internal int[] x = X25519Field.Create();
+ internal int[] y = X25519Field.Create();
+ internal int[] z = X25519Field.Create();
+ internal int[] u = X25519Field.Create();
+ internal int[] v = X25519Field.Create();
+ }
+
+ private class PointExt
+ {
+ internal int[] x = X25519Field.Create();
+ internal int[] y = X25519Field.Create();
+ internal int[] z = X25519Field.Create();
+ internal int[] t = X25519Field.Create();
+ }
+
+ private class PointPrecomp
+ {
+ internal int[] ypx_h = X25519Field.Create();
+ internal int[] ymx_h = X25519Field.Create();
+ internal int[] xyd = X25519Field.Create();
+ }
+
+ private static byte[] CalculateS(byte[] r, byte[] k, byte[] s)
+ {
+ uint[] t = new uint[ScalarUints * 2]; DecodeScalar(r, 0, t);
+ uint[] u = new uint[ScalarUints]; DecodeScalar(k, 0, u);
+ uint[] v = new uint[ScalarUints]; DecodeScalar(s, 0, v);
+
+ Nat256.MulAddTo(u, v, t);
+
+ byte[] result = new byte[ScalarBytes * 2];
+ for (int i = 0; i < t.Length; ++i)
+ {
+ Encode32(t[i], result, i * 4);
+ }
+ return ReduceScalar(result);
+ }
+
+ private static bool CheckPointVar(byte[] p)
+ {
+ uint[] t = new uint[8];
+ Decode32(p, 0, t, 0, 8);
+ t[7] &= 0x7FFFFFFFU;
+ return !Nat256.Gte(t, P);
+ }
+
+ private static bool CheckScalarVar(byte[] s)
+ {
+ uint[] n = new uint[ScalarUints];
+ DecodeScalar(s, 0, n);
+ return !Nat256.Gte(n, L);
+ }
+
+ private static uint Decode24(byte[] bs, int off)
+ {
+ uint n = bs[off];
+ n |= (uint)bs[++off] << 8;
+ n |= (uint)bs[++off] << 16;
+ return n;
+ }
+
+ 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;
+ }
+
+ private static void Decode32(byte[] bs, int bsOff, uint[] n, int nOff, int nLen)
+ {
+ for (int i = 0; i < nLen; ++i)
+ {
+ n[nOff + i] = Decode32(bs, bsOff + i * 4);
+ }
+ }
+
+ private static bool DecodePointVar(byte[] p, int pOff, bool negate, PointExt r)
+ {
+ byte[] py = Arrays.CopyOfRange(p, pOff, pOff + PointBytes);
+ if (!CheckPointVar(py))
+ {
+ return false;
+ }
+
+ int x_0 = (py[PointBytes - 1] & 0x80) >> 7;
+ py[PointBytes - 1] &= 0x7F;
+
+ X25519Field.Decode(py, 0, r.y);
+
+ int[] u = X25519Field.Create();
+ int[] v = X25519Field.Create();
+
+ X25519Field.Sqr(r.y, u);
+ X25519Field.Mul(C_d, u, v);
+ X25519Field.SubOne(u);
+ X25519Field.AddOne(v);
+
+ if (!X25519Field.SqrtRatioVar(u, v, r.x))
+ {
+ return false;
+ }
+
+ X25519Field.Normalize(r.x);
+ if (x_0 == 1 && X25519Field.IsZeroVar(r.x))
+ {
+ return false;
+ }
+
+ if (negate ^ (x_0 != (r.x[0] & 1)))
+ {
+ X25519Field.Negate(r.x, r.x);
+ }
+
+ PointExtendXY(r);
+ return true;
+ }
+
+ private static void DecodeScalar(byte[] k, int kOff, uint[] n)
+ {
+ Decode32(k, kOff, n, 0, ScalarUints);
+ }
+
+ private static void Encode24(uint n, byte[] bs, int off)
+ {
+ bs[off] = (byte)(n);
+ bs[++off] = (byte)(n >> 8);
+ bs[++off] = (byte)(n >> 16);
+ }
+
+ 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);
+ }
+
+ private static void Encode56(ulong n, byte[] bs, int off)
+ {
+ Encode32((uint)n, bs, off);
+ Encode24((uint)(n >> 32), bs, off + 4);
+ }
+
+ private static void EncodePoint(PointAccum p, byte[] r, int rOff)
+ {
+ int[] x = X25519Field.Create();
+ int[] y = X25519Field.Create();
+
+ X25519Field.Inv(p.z, y);
+ X25519Field.Mul(p.x, y, x);
+ X25519Field.Mul(p.y, y, y);
+ X25519Field.Normalize(x);
+ X25519Field.Normalize(y);
+
+ X25519Field.Encode(y, r, rOff);
+ r[rOff + PointBytes - 1] |= (byte)((x[0] & 1) << 7);
+ }
+
+ public static void GeneratePublicKey(byte[] sk, int skOff, byte[] pk, int pkOff)
+ {
+ Sha512Digest d = new Sha512Digest();
+ byte[] h = new byte[d.GetDigestSize()];
+
+ d.BlockUpdate(sk, skOff, SecretKeySize);
+ d.DoFinal(h, 0);
+
+ byte[] s = new byte[ScalarBytes];
+ PruneScalar(h, 0, s);
+
+ ScalarMultBaseEncoded(s, pk, pkOff);
+ }
+
+ private static sbyte[] GetWnaf(uint[] n, int width)
+ {
+ Debug.Assert(n[ScalarUints - 1] >> 31 == 0);
+
+ uint[] t = new uint[ScalarUints * 2];
+ {
+ uint c = 0;
+ int tPos = t.Length, i = ScalarUints;
+ while (--i >= 0)
+ {
+ uint next = n[i];
+ t[--tPos] = (next >> 16) | (c << 16);
+ t[--tPos] = c = next;
+ }
+ }
+
+ sbyte[] ws = new sbyte[256];
+
+ uint pow2 = 1U << width;
+ uint mask = pow2 - 1U;
+ uint sign = pow2 >> 1;
+
+ uint carry = 0U;
+ int j = 0;
+ for (int i = 0; i < t.Length; ++i, j -= 16)
+ {
+ uint word = t[i];
+ while (j < 16)
+ {
+ uint word16 = word >> j;
+ uint bit = word16 & 1U;
+
+ if (bit == carry)
+ {
+ ++j;
+ continue;
+ }
+
+ uint digit = (word16 & mask) + carry;
+ carry = digit & sign;
+ digit -= (carry << 1);
+ carry >>= (width - 1);
+
+ ws[(i << 4) + j] = (sbyte)digit;
+
+ j += width;
+ }
+ }
+
+ Debug.Assert(carry == 0);
+
+ return ws;
+ }
+
+ private static void ImplSign(Sha512Digest d, byte[] h, byte[] s, byte[] pk, int pkOff, byte[] m, int mOff, int mLen, byte[] sig, int sigOff)
+ {
+ d.BlockUpdate(h, ScalarBytes, ScalarBytes);
+ d.BlockUpdate(m, mOff, mLen);
+ d.DoFinal(h, 0);
+
+ byte[] r = ReduceScalar(h);
+ byte[] R = new byte[PointBytes];
+ ScalarMultBaseEncoded(r, R, 0);
+
+ d.BlockUpdate(R, 0, PointBytes);
+ d.BlockUpdate(pk, 0, PointBytes);
+ d.BlockUpdate(m, mOff, mLen);
+ d.DoFinal(h, 0);
+
+ byte[] k = ReduceScalar(h);
+ byte[] S = CalculateS(r, k, s);
+
+ Array.Copy(R, 0, sig, sigOff, PointBytes);
+ Array.Copy(S, 0, sig, sigOff + PointBytes, ScalarBytes);
+ }
+
+ private static void PointAddVar(bool negate, PointExt p, PointAccum r)
+ {
+ int[] A = X25519Field.Create();
+ int[] B = X25519Field.Create();
+ int[] C = X25519Field.Create();
+ int[] D = X25519Field.Create();
+ int[] E = r.u;
+ int[] F = X25519Field.Create();
+ int[] G = X25519Field.Create();
+ int[] H = r.v;
+
+ int[] c, d, f, g;
+ if (negate)
+ {
+ c = D; d = C; f = G; g = F;
+ }
+ else
+ {
+ c = C; d = D; f = F; g = G;
+ }
+
+ X25519Field.Apm(r.y, r.x, B, A);
+ X25519Field.Apm(p.y, p.x, d, c);
+ X25519Field.Mul(A, C, A);
+ X25519Field.Mul(B, D, B);
+ X25519Field.Mul(r.u, r.v, C);
+ X25519Field.Mul(C, p.t, C);
+ X25519Field.Mul(C, C_d2, C);
+ X25519Field.Mul(r.z, p.z, D);
+ X25519Field.Add(D, D, D);
+ X25519Field.Apm(B, A, H, E);
+ X25519Field.Apm(D, C, g, f);
+ X25519Field.Carry(g);
+ X25519Field.Mul(E, F, r.x);
+ X25519Field.Mul(G, H, r.y);
+ X25519Field.Mul(F, G, r.z);
+ }
+
+ private static void PointAddVar(bool negate, PointExt p, PointExt q, PointExt r)
+ {
+ int[] A = X25519Field.Create();
+ int[] B = X25519Field.Create();
+ int[] C = X25519Field.Create();
+ int[] D = X25519Field.Create();
+ int[] E = X25519Field.Create();
+ int[] F = X25519Field.Create();
+ int[] G = X25519Field.Create();
+ int[] H = X25519Field.Create();
+
+ int[] c, d, f, g;
+ if (negate)
+ {
+ c = D; d = C; f = G; g = F;
+ }
+ else
+ {
+ c = C; d = D; f = F; g = G;
+ }
+
+ X25519Field.Apm(p.y, p.x, B, A);
+ X25519Field.Apm(q.y, q.x, d, c);
+ X25519Field.Mul(A, C, A);
+ X25519Field.Mul(B, D, B);
+ X25519Field.Mul(p.t, q.t, C);
+ X25519Field.Mul(C, C_d2, C);
+ X25519Field.Mul(p.z, q.z, D);
+ X25519Field.Add(D, D, D);
+ X25519Field.Apm(B, A, H, E);
+ X25519Field.Apm(D, C, g, f);
+ X25519Field.Carry(g);
+ X25519Field.Mul(E, F, r.x);
+ X25519Field.Mul(G, H, r.y);
+ X25519Field.Mul(F, G, r.z);
+ X25519Field.Mul(E, H, r.t);
+ }
+
+ private static void PointAddPrecomp(PointPrecomp p, PointAccum r)
+ {
+ int[] A = X25519Field.Create();
+ int[] B = X25519Field.Create();
+ int[] C = X25519Field.Create();
+ int[] E = r.u;
+ int[] F = X25519Field.Create();
+ int[] G = X25519Field.Create();
+ int[] H = r.v;
+
+ X25519Field.Apm(r.y, r.x, B, A);
+ X25519Field.Mul(A, p.ymx_h, A);
+ X25519Field.Mul(B, p.ypx_h, B);
+ X25519Field.Mul(r.u, r.v, C);
+ X25519Field.Mul(C, p.xyd, C);
+ X25519Field.Apm(B, A, H, E);
+ X25519Field.Apm(r.z, C, G, F);
+ X25519Field.Carry(G);
+ X25519Field.Mul(E, F, r.x);
+ X25519Field.Mul(G, H, r.y);
+ X25519Field.Mul(F, G, r.z);
+ }
+
+ private static PointExt PointCopy(PointAccum p)
+ {
+ PointExt r = new PointExt();
+ X25519Field.Copy(p.x, 0, r.x, 0);
+ X25519Field.Copy(p.y, 0, r.y, 0);
+ X25519Field.Copy(p.z, 0, r.z, 0);
+ X25519Field.Mul(p.u, p.v, r.t);
+ return r;
+ }
+
+ private static PointExt PointCopy(PointExt p)
+ {
+ PointExt r = new PointExt();
+ X25519Field.Copy(p.x, 0, r.x, 0);
+ X25519Field.Copy(p.y, 0, r.y, 0);
+ X25519Field.Copy(p.z, 0, r.z, 0);
+ X25519Field.Copy(p.t, 0, r.t, 0);
+ return r;
+ }
+
+ private static void PointDouble(PointAccum r)
+ {
+ int[] A = X25519Field.Create();
+ int[] B = X25519Field.Create();
+ int[] C = X25519Field.Create();
+ int[] E = r.u;
+ int[] F = X25519Field.Create();
+ int[] G = X25519Field.Create();
+ int[] H = r.v;
+
+ X25519Field.Sqr(r.x, A);
+ X25519Field.Sqr(r.y, B);
+ X25519Field.Sqr(r.z, C);
+ X25519Field.Add(C, C, C);
+ X25519Field.Apm(A, B, H, G);
+ X25519Field.Add(r.x, r.y, E);
+ X25519Field.Sqr(E, E);
+ X25519Field.Sub(H, E, E);
+ X25519Field.Add(C, G, F);
+ X25519Field.Carry(F);
+ X25519Field.Mul(E, F, r.x);
+ X25519Field.Mul(G, H, r.y);
+ X25519Field.Mul(F, G, r.z);
+ }
+
+ private static void PointExtendXY(PointAccum p)
+ {
+ X25519Field.One(p.z);
+ X25519Field.Copy(p.x, 0, p.u, 0);
+ X25519Field.Copy(p.y, 0, p.v, 0);
+ }
+
+ private static void PointExtendXY(PointExt p)
+ {
+ X25519Field.One(p.z);
+ X25519Field.Mul(p.x, p.y, p.t);
+ }
+
+ private static void PointLookup(int block, int index, PointPrecomp p)
+ {
+ Debug.Assert(0 <= block && block < PrecompBlocks);
+ Debug.Assert(0 <= index && index < PrecompPoints);
+
+ int off = block * PrecompPoints * 3 * X25519Field.Size;
+
+ for (int i = 0; i < PrecompPoints; ++i)
+ {
+ int mask = ((i ^ index) - 1) >> 31;
+ Nat.CMov(X25519Field.Size, mask, precompBase, off, p.ypx_h, 0); off += X25519Field.Size;
+ Nat.CMov(X25519Field.Size, mask, precompBase, off, p.ymx_h, 0); off += X25519Field.Size;
+ Nat.CMov(X25519Field.Size, mask, precompBase, off, p.xyd, 0); off += X25519Field.Size;
+ }
+ }
+
+ private static PointExt[] PointPrecompVar(PointExt p, int count)
+ {
+ Debug.Assert(count > 0);
+
+ PointExt d = new PointExt();
+ PointAddVar(false, p, p, d);
+
+ PointExt[] table = new PointExt[count];
+ table[0] = PointCopy(p);
+ for (int i = 1; i < count; ++i)
+ {
+ PointAddVar(false, table[i - 1], d, table[i] = new PointExt());
+ }
+ return table;
+ }
+
+ private static void PointSetNeutral(PointAccum p)
+ {
+ X25519Field.Zero(p.x);
+ X25519Field.One(p.y);
+ X25519Field.One(p.z);
+ X25519Field.Zero(p.u);
+ X25519Field.One(p.v);
+ }
+
+ private static void PointSetNeutral(PointExt p)
+ {
+ X25519Field.Zero(p.x);
+ X25519Field.One(p.y);
+ X25519Field.One(p.z);
+ X25519Field.Zero(p.t);
+ }
+
+ [MethodImpl(MethodImplOptions.Synchronized)]
+ public static void Precompute()
+ {
+ if (precompBase != null)
+ {
+ return;
+ }
+
+ // Precomputed table for the base point in verification ladder
+ {
+ PointExt b = new PointExt();
+ X25519Field.Copy(B_x, 0, b.x, 0);
+ X25519Field.Copy(B_y, 0, b.y, 0);
+ PointExtendXY(b);
+
+ precompBaseTable = PointPrecompVar(b, 1 << (WnafWidthBase - 2));
+ }
+
+ PointAccum p = new PointAccum();
+ X25519Field.Copy(B_x, 0, p.x, 0);
+ X25519Field.Copy(B_y, 0, p.y, 0);
+ PointExtendXY(p);
+
+ precompBase = new int[PrecompBlocks * PrecompPoints * 3 * X25519Field.Size];
+
+ int off = 0;
+ for (int b = 0; b < PrecompBlocks; ++b)
+ {
+ PointExt[] ds = new PointExt[PrecompTeeth];
+
+ PointExt sum = new PointExt();
+ PointSetNeutral(sum);
+
+ for (int t = 0; t < PrecompTeeth; ++t)
+ {
+ PointExt q = PointCopy(p);
+ PointAddVar(true, sum, q, sum);
+ PointDouble(p);
+
+ ds[t] = PointCopy(p);
+
+ for (int s = 1; s < PrecompSpacing; ++s)
+ {
+ PointDouble(p);
+ }
+ }
+
+ PointExt[] points = new PointExt[PrecompPoints];
+ int k = 0;
+ points[k++] = sum;
+
+ for (int t = 0; t < (PrecompTeeth - 1); ++t)
+ {
+ int size = 1 << t;
+ for (int j = 0; j < size; ++j, ++k)
+ {
+ PointAddVar(false, points[k - size], ds[t], points[k] = new PointExt());
+ }
+ }
+
+ Debug.Assert(k == PrecompPoints);
+
+ for (int i = 0; i < PrecompPoints; ++i)
+ {
+ PointExt q = points[i];
+
+ int[] x = X25519Field.Create();
+ int[] y = X25519Field.Create();
+
+ X25519Field.Add(q.z, q.z, x);
+ // TODO[ed25519] Batch inversion
+ X25519Field.Inv(x, y);
+ X25519Field.Mul(q.x, y, x);
+ X25519Field.Mul(q.y, y, y);
+
+ PointPrecomp r = new PointPrecomp();
+ X25519Field.Apm(y, x, r.ypx_h, r.ymx_h);
+ X25519Field.Mul(x, y, r.xyd);
+ X25519Field.Mul(r.xyd, C_d4, r.xyd);
+
+ X25519Field.Normalize(r.ypx_h);
+ X25519Field.Normalize(r.ymx_h);
+ //X25519Field.Normalize(r.xyd);
+
+ X25519Field.Copy(r.ypx_h, 0, precompBase, off); off += X25519Field.Size;
+ X25519Field.Copy(r.ymx_h, 0, precompBase, off); off += X25519Field.Size;
+ X25519Field.Copy(r.xyd, 0, precompBase, off); off += X25519Field.Size;
+ }
+ }
+
+ Debug.Assert(off == precompBase.Length);
+ }
+
+ private static void PruneScalar(byte[] n, int nOff, byte[] r)
+ {
+ Array.Copy(n, nOff, r, 0, ScalarBytes);
+
+ r[0] &= 0xF8;
+ r[ScalarBytes - 1] &= 0x7F;
+ r[ScalarBytes - 1] |= 0x40;
+ }
+
+ private static byte[] ReduceScalar(byte[] n)
+ {
+ long x00 = Decode32(n, 0) & M32L; // x00:32/--
+ long x01 = (Decode24(n, 4) << 4) & M32L; // x01:28/--
+ long x02 = Decode32(n, 7) & M32L; // x02:32/--
+ long x03 = (Decode24(n, 11) << 4) & M32L; // x03:28/--
+ long x04 = Decode32(n, 14) & M32L; // x04:32/--
+ long x05 = (Decode24(n, 18) << 4) & M32L; // x05:28/--
+ long x06 = Decode32(n, 21) & M32L; // x06:32/--
+ long x07 = (Decode24(n, 25) << 4) & M32L; // x07:28/--
+ long x08 = Decode32(n, 28) & M32L; // x08:32/--
+ long x09 = (Decode24(n, 32) << 4) & M32L; // x09:28/--
+ long x10 = Decode32(n, 35) & M32L; // x10:32/--
+ long x11 = (Decode24(n, 39) << 4) & M32L; // x11:28/--
+ long x12 = Decode32(n, 42) & M32L; // x12:32/--
+ long x13 = (Decode24(n, 46) << 4) & M32L; // x13:28/--
+ long x14 = Decode32(n, 49) & M32L; // x14:32/--
+ long x15 = (Decode24(n, 53) << 4) & M32L; // x15:28/--
+ long x16 = Decode32(n, 56) & M32L; // x16:32/--
+ long x17 = (Decode24(n, 60) << 4) & M32L; // x17:28/--
+ long x18 = n[63] & 0xFFL; // x18:08/--
+ long t;
+
+ //x18 += (x17 >> 28); x17 &= M28L;
+ x09 -= x18 * L0; // x09:34/28
+ x10 -= x18 * L1; // x10:33/30
+ x11 -= x18 * L2; // x11:35/28
+ x12 -= x18 * L3; // x12:32/31
+ x13 -= x18 * L4; // x13:28/21
+
+ x17 += (x16 >> 28); x16 &= M28L; // x17:28/--, x16:28/--
+ x08 -= x17 * L0; // x08:54/32
+ x09 -= x17 * L1; // x09:52/51
+ x10 -= x17 * L2; // x10:55/34
+ x11 -= x17 * L3; // x11:51/36
+ x12 -= x17 * L4; // x12:41/--
+
+ //x16 += (x15 >> 28); x15 &= M28L;
+ x07 -= x16 * L0; // x07:54/28
+ x08 -= x16 * L1; // x08:54/53
+ x09 -= x16 * L2; // x09:55/53
+ x10 -= x16 * L3; // x10:55/52
+ x11 -= x16 * L4; // x11:51/41
+
+ x15 += (x14 >> 28); x14 &= M28L; // x15:28/--, x14:28/--
+ x06 -= x15 * L0; // x06:54/32
+ x07 -= x15 * L1; // x07:54/53
+ x08 -= x15 * L2; // x08:56/--
+ x09 -= x15 * L3; // x09:55/54
+ x10 -= x15 * L4; // x10:55/53
+
+ //x14 += (x13 >> 28); x13 &= M28L;
+ x05 -= x14 * L0; // x05:54/28
+ x06 -= x14 * L1; // x06:54/53
+ x07 -= x14 * L2; // x07:56/--
+ x08 -= x14 * L3; // x08:56/51
+ x09 -= x14 * L4; // x09:56/--
+
+ x13 += (x12 >> 28); x12 &= M28L; // x13:28/22, x12:28/--
+ x04 -= x13 * L0; // x04:54/49
+ x05 -= x13 * L1; // x05:54/53
+ x06 -= x13 * L2; // x06:56/--
+ x07 -= x13 * L3; // x07:56/52
+ x08 -= x13 * L4; // x08:56/52
+
+ x12 += (x11 >> 28); x11 &= M28L; // x12:28/24, x11:28/--
+ x03 -= x12 * L0; // x03:54/49
+ x04 -= x12 * L1; // x04:54/51
+ x05 -= x12 * L2; // x05:56/--
+ x06 -= x12 * L3; // x06:56/52
+ x07 -= x12 * L4; // x07:56/53
+
+ x11 += (x10 >> 28); x10 &= M28L; // x11:29/--, x10:28/--
+ x02 -= x11 * L0; // x02:55/32
+ x03 -= x11 * L1; // x03:55/--
+ x04 -= x11 * L2; // x04:56/55
+ x05 -= x11 * L3; // x05:56/52
+ x06 -= x11 * L4; // x06:56/53
+
+ x10 += (x09 >> 28); x09 &= M28L; // x10:29/--, x09:28/--
+ x01 -= x10 * L0; // x01:55/28
+ x02 -= x10 * L1; // x02:55/54
+ x03 -= x10 * L2; // x03:56/55
+ x04 -= x10 * L3; // x04:57/--
+ x05 -= x10 * L4; // x05:56/53
+
+ x08 += (x07 >> 28); x07 &= M28L; // x08:56/53, x07:28/--
+ x09 += (x08 >> 28); x08 &= M28L; // x09:29/25, x08:28/--
+
+ t = (x08 >> 27) & 1L;
+ x09 += t; // x09:29/26
+
+ x00 -= x09 * L0; // x00:55/53
+ x01 -= x09 * L1; // x01:55/54
+ x02 -= x09 * L2; // x02:57/--
+ x03 -= x09 * L3; // x03:57/--
+ x04 -= x09 * L4; // x04:57/42
+
+ x01 += (x00 >> 28); x00 &= M28L;
+ x02 += (x01 >> 28); x01 &= M28L;
+ x03 += (x02 >> 28); x02 &= M28L;
+ x04 += (x03 >> 28); x03 &= M28L;
+ x05 += (x04 >> 28); x04 &= M28L;
+ x06 += (x05 >> 28); x05 &= M28L;
+ x07 += (x06 >> 28); x06 &= M28L;
+ x08 += (x07 >> 28); x07 &= M28L;
+ x09 = (x08 >> 28); x08 &= M28L;
+
+ x09 -= t;
+
+ Debug.Assert(x09 == 0L || x09 == -1L);
+
+ x00 += x09 & L0;
+ x01 += x09 & L1;
+ x02 += x09 & L2;
+ x03 += x09 & L3;
+ x04 += x09 & L4;
+
+ x01 += (x00 >> 28); x00 &= M28L;
+ x02 += (x01 >> 28); x01 &= M28L;
+ x03 += (x02 >> 28); x02 &= M28L;
+ x04 += (x03 >> 28); x03 &= M28L;
+ x05 += (x04 >> 28); x04 &= M28L;
+ x06 += (x05 >> 28); x05 &= M28L;
+ x07 += (x06 >> 28); x06 &= M28L;
+ x08 += (x07 >> 28); x07 &= M28L;
+
+ byte[] r = new byte[ScalarBytes];
+ Encode56((ulong)(x00 | (x01 << 28)), r, 0);
+ Encode56((ulong)(x02 | (x03 << 28)), r, 7);
+ Encode56((ulong)(x04 | (x05 << 28)), r, 14);
+ Encode56((ulong)(x06 | (x07 << 28)), r, 21);
+ Encode32((uint)x08, r, 28);
+ return r;
+ }
+
+ private static void ScalarMultBase(byte[] k, PointAccum r)
+ {
+ Precompute();
+
+ PointSetNeutral(r);
+
+ uint[] n = new uint[ScalarUints];
+ DecodeScalar(k, 0, n);
+
+ // Recode the scalar into signed-digit form, then group comb bits in each block
+ {
+ uint c1 = Nat.CAdd(ScalarUints, ~(int)n[0] & 1, n, L, n); Debug.Assert(c1 == 0);
+ uint c2 = Nat.ShiftDownBit(ScalarUints, n, 1U); Debug.Assert(c2 == (1U << 31));
+
+ for (int i = 0; i < ScalarUints; ++i)
+ {
+ n[i] = Interleave.Shuffle2(n[i]);
+ }
+ }
+
+ PointPrecomp p = new PointPrecomp();
+
+ int cOff = (PrecompSpacing - 1) * PrecompTeeth;
+ for (; ; )
+ {
+ for (int b = 0; b < PrecompBlocks; ++b)
+ {
+ uint w = n[b] >> cOff;
+ int sign = (int)(w >> (PrecompTeeth - 1)) & 1;
+ int abs = ((int)w ^ -sign) & PrecompMask;
+
+ Debug.Assert(sign == 0 || sign == 1);
+ Debug.Assert(0 <= abs && abs < PrecompPoints);
+
+ PointLookup(b, abs, p);
+
+ X25519Field.CSwap(sign, p.ypx_h, p.ymx_h);
+ X25519Field.CNegate(sign, p.xyd);
+
+ PointAddPrecomp(p, r);
+ }
+
+ if ((cOff -= PrecompTeeth) < 0)
+ {
+ break;
+ }
+
+ PointDouble(r);
+ }
+ }
+
+ private static void ScalarMultBaseEncoded(byte[] k, byte[] r, int rOff)
+ {
+ PointAccum p = new PointAccum();
+ ScalarMultBase(k, p);
+ EncodePoint(p, r, rOff);
+ }
+
+ private static void ScalarMultStraussVar(uint[] nb, uint[] np, PointExt p, PointAccum r)
+ {
+ Precompute();
+
+ int width = 5;
+
+ sbyte[] ws_b = GetWnaf(nb, WnafWidthBase);
+ sbyte[] ws_p = GetWnaf(np, width);
+
+ PointExt[] tp = PointPrecompVar(p, 1 << (width - 2));
+
+ PointSetNeutral(r);
+
+ int bit = 255;
+ while (bit > 0 && (ws_b[bit] | ws_p[bit]) == 0)
+ {
+ --bit;
+ }
+
+ for (; ; )
+ {
+ int wb = ws_b[bit];
+ if (wb != 0)
+ {
+ int sign = wb >> 31;
+ int index = (wb ^ sign) >> 1;
+
+ PointAddVar((sign != 0), precompBaseTable[index], r);
+ }
+
+ int wp = ws_p[bit];
+ if (wp != 0)
+ {
+ int sign = wp >> 31;
+ int index = (wp ^ sign) >> 1;
+
+ PointAddVar((sign != 0), tp[index], r);
+ }
+
+ if (--bit < 0)
+ {
+ break;
+ }
+
+ PointDouble(r);
+ }
+ }
+
+ public static void Sign(byte[] sk, int skOff, byte[] m, int mOff, int mLen, byte[] sig, int sigOff)
+ {
+ Sha512Digest d = new Sha512Digest();
+ byte[] h = new byte[d.GetDigestSize()];
+
+ d.BlockUpdate(sk, skOff, SecretKeySize);
+ d.DoFinal(h, 0);
+
+ byte[] s = new byte[ScalarBytes];
+ PruneScalar(h, 0, s);
+
+ byte[] pk = new byte[PointBytes];
+ ScalarMultBaseEncoded(s, pk, 0);
+
+ ImplSign(d, h, s, pk, 0, m, mOff, mLen, sig, sigOff);
+ }
+
+ public static void Sign(byte[] sk, int skOff, byte[] pk, int pkOff, byte[] m, int mOff, int mLen, byte[] sig, int sigOff)
+ {
+ Sha512Digest d = new Sha512Digest();
+ byte[] h = new byte[d.GetDigestSize()];
+
+ d.BlockUpdate(sk, skOff, SecretKeySize);
+ d.DoFinal(h, 0);
+
+ byte[] s = new byte[ScalarBytes];
+ PruneScalar(h, 0, s);
+
+ ImplSign(d, h, s, pk, pkOff, m, mOff, mLen, sig, sigOff);
+ }
+
+ public static bool Verify(byte[] sig, int sigOff, byte[] pk, int pkOff, byte[] m, int mOff, int mLen)
+ {
+ byte[] R = Arrays.CopyOfRange(sig, sigOff, sigOff + PointBytes);
+ byte[] S = Arrays.CopyOfRange(sig, sigOff + PointBytes, sigOff + SignatureSize);
+
+ if (!CheckPointVar(R))
+ {
+ return false;
+ }
+ if (!CheckScalarVar(S))
+ {
+ return false;
+ }
+
+ PointExt pA = new PointExt();
+ if (!DecodePointVar(pk, pkOff, true, pA))
+ {
+ return false;
+ }
+
+ Sha512Digest d = new Sha512Digest();
+ byte[] h = new byte[d.GetDigestSize()];
+
+ d.BlockUpdate(R, 0, PointBytes);
+ d.BlockUpdate(pk, pkOff, PointBytes);
+ d.BlockUpdate(m, mOff, mLen);
+ d.DoFinal(h, 0);
+
+ byte[] k = ReduceScalar(h);
+
+ uint[] nS = new uint[ScalarUints];
+ DecodeScalar(S, 0, nS);
+
+ uint[] nA = new uint[ScalarUints];
+ DecodeScalar(k, 0, nA);
+
+ PointAccum pR = new PointAccum();
+ ScalarMultStraussVar(nS, nA, pA, pR);
+
+ byte[] check = new byte[PointBytes];
+ EncodePoint(pR, check, 0);
+
+ return Arrays.AreEqual(check, R);
+ }
+ }
+}
diff --git a/crypto/src/math/ec/rfc8032/Ed448.cs b/crypto/src/math/ec/rfc8032/Ed448.cs
new file mode 100644
index 000000000..52c215160
--- /dev/null
+++ b/crypto/src/math/ec/rfc8032/Ed448.cs
@@ -0,0 +1,1067 @@
+using System;
+using System.Diagnostics;
+using System.Runtime.CompilerServices;
+
+using Org.BouncyCastle.Crypto.Digests;
+using Org.BouncyCastle.Math.EC.Rfc7748;
+using Org.BouncyCastle.Math.Raw;
+using Org.BouncyCastle.Utilities;
+
+namespace Org.BouncyCastle.Math.EC.Rfc8032
+{
+ public abstract class Ed448
+ {
+ private const ulong M26UL = 0x03FFFFFFUL;
+ private const ulong M28UL = 0x0FFFFFFFUL;
+
+ private const int PointBytes = 57;
+ private const int ScalarUints = 14;
+ private const int ScalarBytes = ScalarUints * 4 + 1;
+
+ public static readonly int PublicKeySize = PointBytes;
+ public static readonly int SecretKeySize = 57;
+ public static readonly int SignatureSize = PointBytes + ScalarBytes;
+
+ private static readonly byte[] Dom4Prefix = Strings.ToByteArray("SigEd448");
+
+ private static readonly uint[] P = { 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU,
+ 0xFFFFFFFEU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU };
+ private static readonly uint[] L = { 0xAB5844F3U, 0x2378C292U, 0x8DC58F55U, 0x216CC272U, 0xAED63690U, 0xC44EDB49U, 0x7CCA23E9U,
+ 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0xFFFFFFFFU, 0x3FFFFFFFU };
+ private static readonly BigInteger N = Nat.ToBigInteger(L.Length, L);
+
+ private const int L_0 = 0x04A7BB0D; // L_0:26/24
+ private const int L_1 = 0x0873D6D5; // L_1:27/23
+ private const int L_2 = 0x0A70AADC; // L_2:27/26
+ private const int L_3 = 0x03D8D723; // L_3:26/--
+ private const int L_4 = 0x096FDE93; // L_4:27/25
+ private const int L_5 = 0x0B65129C; // L_5:27/26
+ private const int L_6 = 0x063BB124; // L_6:27/--
+ private const int L_7 = 0x08335DC1; // L_7:27/22
+
+ private const int L4_0 = 0x029EEC34; // L4_0:25/24
+ private const int L4_1 = 0x01CF5B55; // L4_1:25/--
+ private const int L4_2 = 0x09C2AB72; // L4_2:27/25
+ private const int L4_3 = 0x0F635C8E; // L4_3:28/--
+ private const int L4_4 = 0x05BF7A4C; // L4_4:26/25
+ private const int L4_5 = 0x0D944A72; // L4_5:28/--
+ private const int L4_6 = 0x08EEC492; // L4_6:27/24
+ private const int L4_7 = 0x20CD7705; // L4_7:29/24
+
+ private static readonly uint[] B_x = { 0x070CC05EU, 0x026A82BCU, 0x00938E26U, 0x080E18B0U, 0x0511433BU, 0x0F72AB66U, 0x0412AE1AU,
+ 0x0A3D3A46U, 0x0A6DE324U, 0x00F1767EU, 0x04657047U, 0x036DA9E1U, 0x05A622BFU, 0x0ED221D1U, 0x066BED0DU, 0x04F1970CU };
+ private static readonly uint[] B_y = { 0x0230FA14U, 0x008795BFU, 0x07C8AD98U, 0x0132C4EDU, 0x09C4FDBDU, 0x01CE67C3U, 0x073AD3FFU,
+ 0x005A0C2DU, 0x07789C1EU, 0x0A398408U, 0x0A73736CU, 0x0C7624BEU, 0x003756C9U, 0x02488762U, 0x016EB6BCU, 0x0693F467U };
+ private const int C_d = -39081;
+
+ private const int WnafWidthBase = 7;
+
+ private const int PrecompBlocks = 5;
+ private const int PrecompTeeth = 5;
+ private const int PrecompSpacing = 18;
+ private const int PrecompPoints = 1 << (PrecompTeeth - 1);
+ private const int PrecompMask = PrecompPoints - 1;
+
+ // TODO[ed448] Convert to PointPrecomp
+ private static PointExt[] precompBaseTable = null;
+ private static uint[] precompBase = null;
+
+ private class PointExt
+ {
+ internal uint[] x = X448Field.Create();
+ internal uint[] y = X448Field.Create();
+ internal uint[] z = X448Field.Create();
+ }
+
+ private class PointPrecomp
+ {
+ internal uint[] x = X448Field.Create();
+ internal uint[] y = X448Field.Create();
+ }
+
+ private static byte[] CalculateS(byte[] r, byte[] k, byte[] s)
+ {
+ uint[] t = new uint[ScalarUints * 2]; DecodeScalar(r, 0, t);
+ uint[] u = new uint[ScalarUints]; DecodeScalar(k, 0, u);
+ uint[] v = new uint[ScalarUints]; DecodeScalar(s, 0, v);
+
+ Nat.MulAddTo(14, u, v, t);
+
+ byte[] result = new byte[ScalarBytes * 2];
+ for (int i = 0; i < t.Length; ++i)
+ {
+ Encode32(t[i], result, i * 4);
+ }
+ return ReduceScalar(result);
+ }
+
+ private static bool CheckContextVar(byte[] ctx)
+ {
+ return ctx != null && ctx.Length < 256;
+ }
+
+ private static bool CheckPointVar(byte[] p)
+ {
+ if ((p[PointBytes - 1] & 0x7F) != 0x00)
+ {
+ return false;
+ }
+
+ uint[] t = new uint[14];
+ Decode32(p, 0, t, 0, 14);
+ return !Nat.Gte(14, t, P);
+ }
+
+ private static bool CheckScalarVar(byte[] s)
+ {
+ if (s[ScalarBytes - 1] != 0x00)
+ {
+ return false;
+ }
+
+ uint[] n = new uint[ScalarUints];
+ DecodeScalar(s, 0, n);
+ return !Nat.Gte(ScalarUints, n, L);
+ }
+
+ private static uint Decode16(byte[] bs, int off)
+ {
+ uint n = bs[off];
+ n |= (uint)bs[++off] << 8;
+ return n;
+ }
+
+ private static uint Decode24(byte[] bs, int off)
+ {
+ uint n = bs[off];
+ n |= (uint)bs[++off] << 8;
+ n |= (uint)bs[++off] << 16;
+ return n;
+ }
+
+ 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;
+ }
+
+ private static void Decode32(byte[] bs, int bsOff, uint[] n, int nOff, int nLen)
+ {
+ for (int i = 0; i < nLen; ++i)
+ {
+ n[nOff + i] = Decode32(bs, bsOff + i * 4);
+ }
+ }
+
+ private static bool DecodePointVar(byte[] p, int pOff, bool negate, PointExt r)
+ {
+ byte[] py = Arrays.CopyOfRange(p, pOff, pOff + PointBytes);
+ if (!CheckPointVar(py))
+ {
+ return false;
+ }
+
+ int x_0 = (py[PointBytes - 1] & 0x80) >> 7;
+ py[PointBytes - 1] &= 0x7F;
+
+ X448Field.Decode(py, 0, r.y);
+
+ uint[] u = X448Field.Create();
+ uint[] v = X448Field.Create();
+
+ X448Field.Sqr(r.y, u);
+ X448Field.Mul(u, (uint)-C_d, v);
+ X448Field.Negate(u, u);
+ X448Field.AddOne(u);
+ X448Field.AddOne(v);
+
+ if (!X448Field.SqrtRatioVar(u, v, r.x))
+ {
+ return false;
+ }
+
+ X448Field.Normalize(r.x);
+ if (x_0 == 1 && X448Field.IsZeroVar(r.x))
+ {
+ return false;
+ }
+
+ if (negate ^ (x_0 != (r.x[0] & 1)))
+ {
+ X448Field.Negate(r.x, r.x);
+ }
+
+ PointExtendXY(r);
+ return true;
+ }
+
+ private static void DecodeScalar(byte[] k, int kOff, uint[] n)
+ {
+ Debug.Assert(k[kOff + ScalarBytes - 1] == 0x00);
+
+ Decode32(k, kOff, n, 0, ScalarUints);
+ }
+
+ private static void Dom4(ShakeDigest d, byte x, byte[] y)
+ {
+ d.BlockUpdate(Dom4Prefix, 0, Dom4Prefix.Length);
+ d.Update(x);
+ d.Update((byte)y.Length);
+ d.BlockUpdate(y, 0, y.Length);
+ }
+
+ private static void Encode24(uint n, byte[] bs, int off)
+ {
+ bs[off] = (byte)(n);
+ bs[++off] = (byte)(n >> 8);
+ bs[++off] = (byte)(n >> 16);
+ }
+
+ 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);
+ }
+
+ private static void Encode56(ulong n, byte[] bs, int off)
+ {
+ Encode32((uint)n, bs, off);
+ Encode24((uint)(n >> 32), bs, off + 4);
+ }
+
+ private static void EncodePoint(PointExt p, byte[] r, int rOff)
+ {
+ uint[] x = X448Field.Create();
+ uint[] y = X448Field.Create();
+
+ X448Field.Inv(p.z, y);
+ X448Field.Mul(p.x, y, x);
+ X448Field.Mul(p.y, y, y);
+ X448Field.Normalize(x);
+ X448Field.Normalize(y);
+
+ X448Field.Encode(y, r, rOff);
+ r[rOff + PointBytes - 1] = (byte)((x[0] & 1) << 7);
+ }
+
+ public static void GeneratePublicKey(byte[] sk, int skOff, byte[] pk, int pkOff)
+ {
+ ShakeDigest d = new ShakeDigest(256);
+ byte[] h = new byte[ScalarBytes * 2];
+
+ d.BlockUpdate(sk, skOff, SecretKeySize);
+ d.DoFinal(h, 0, h.Length);
+
+ byte[] s = new byte[ScalarBytes];
+ PruneScalar(h, 0, s);
+
+ ScalarMultBaseEncoded(s, pk, pkOff);
+ }
+
+ private static sbyte[] GetWnaf(uint[] n, int width)
+ {
+ Debug.Assert(n[ScalarUints - 1] >> 31 == 0U);
+
+ uint[] t = new uint[ScalarUints * 2];
+ {
+ uint c = 0;
+ int tPos = t.Length, i = ScalarUints;
+ while (--i >= 0)
+ {
+ uint next = n[i];
+ t[--tPos] = (next >> 16) | (c << 16);
+ t[--tPos] = c = next;
+ }
+ }
+
+ sbyte[] ws = new sbyte[448];
+
+ uint pow2 = 1U << width;
+ uint mask = pow2 - 1U;
+ uint sign = pow2 >> 1;
+
+ uint carry = 0U;
+ int j = 0;
+ for (int i = 0; i < t.Length; ++i, j -= 16)
+ {
+ uint word = t[i];
+ while (j < 16)
+ {
+ uint word16 = word >> j;
+ uint bit = word16 & 1U;
+
+ if (bit == carry)
+ {
+ ++j;
+ continue;
+ }
+
+ uint digit = (word16 & mask) + carry;
+ carry = digit & sign;
+ digit -= (carry << 1);
+ carry >>= (width - 1);
+
+ ws[(i << 4) + j] = (sbyte)digit;
+
+ j += width;
+ }
+ }
+
+ Debug.Assert(carry == 0);
+
+ return ws;
+ }
+
+ private static void ImplSign(ShakeDigest d, byte[] h, byte[] s, byte[] pk, int pkOff, byte[] ctx, byte[] m, int mOff, int mLen, byte[] sig, int sigOff)
+ {
+ byte phflag = 0x00;
+
+ Dom4(d, phflag, ctx);
+ d.BlockUpdate(h, ScalarBytes, ScalarBytes);
+ d.BlockUpdate(m, mOff, mLen);
+ d.DoFinal(h, 0, h.Length);
+
+ byte[] r = ReduceScalar(h);
+ byte[] R = new byte[PointBytes];
+ ScalarMultBaseEncoded(r, R, 0);
+
+ Dom4(d, phflag, ctx);
+ d.BlockUpdate(R, 0, PointBytes);
+ d.BlockUpdate(pk, pkOff, PointBytes);
+ d.BlockUpdate(m, mOff, mLen);
+ d.DoFinal(h, 0, h.Length);
+
+ byte[] k = ReduceScalar(h);
+ byte[] S = CalculateS(r, k, s);
+
+ Array.Copy(R, 0, sig, sigOff, PointBytes);
+ Array.Copy(S, 0, sig, sigOff + PointBytes, ScalarBytes);
+ }
+
+ private static void PointAddVar(bool negate, PointExt p, PointExt r)
+ {
+ uint[] A = X448Field.Create();
+ uint[] B = X448Field.Create();
+ uint[] C = X448Field.Create();
+ uint[] D = X448Field.Create();
+ uint[] E = X448Field.Create();
+ uint[] F = X448Field.Create();
+ uint[] G = X448Field.Create();
+ uint[] H = X448Field.Create();
+
+ uint[] b, e, f, g;
+ if (negate)
+ {
+ b = E; e = B; f = G; g = F;
+ X448Field.Sub(p.y, p.x, H);
+ }
+ else
+ {
+ b = B; e = E; f = F; g = G;
+ X448Field.Add(p.y, p.x, H);
+ }
+
+ X448Field.Mul(p.z, r.z, A);
+ X448Field.Sqr(A, B);
+ X448Field.Mul(p.x, r.x, C);
+ X448Field.Mul(p.y, r.y, D);
+ X448Field.Mul(C, D, E);
+ X448Field.Mul(E, -C_d, E);
+ // X448Field.Apm(B, E, F, G);
+ X448Field.Add(B, E, f);
+ X448Field.Sub(B, E, g);
+ X448Field.Add(r.x, r.y, E);
+ X448Field.Mul(H, E, H);
+ // X448Field.Apm(D, C, B, E);
+ X448Field.Add(D, C, b);
+ X448Field.Sub(D, C, e);
+ X448Field.Carry(b);
+ X448Field.Sub(H, B, H);
+ X448Field.Mul(H, A, H);
+ X448Field.Mul(E, A, E);
+ X448Field.Mul(F, H, r.x);
+ X448Field.Mul(E, G, r.y);
+ X448Field.Mul(F, G, r.z);
+ }
+
+ private static void PointAddPrecomp(PointPrecomp p, PointExt r)
+ {
+ uint[] B = X448Field.Create();
+ uint[] C = X448Field.Create();
+ uint[] D = X448Field.Create();
+ uint[] E = X448Field.Create();
+ uint[] F = X448Field.Create();
+ uint[] G = X448Field.Create();
+ uint[] H = X448Field.Create();
+
+ X448Field.Sqr(r.z, B);
+ X448Field.Mul(p.x, r.x, C);
+ X448Field.Mul(p.y, r.y, D);
+ X448Field.Mul(C, D, E);
+ X448Field.Mul(E, -C_d, E);
+ // X448Field.Apm(B, E, F, G);
+ X448Field.Add(B, E, F);
+ X448Field.Sub(B, E, G);
+ X448Field.Add(p.x, p.y, B);
+ X448Field.Add(r.x, r.y, E);
+ X448Field.Mul(B, E, H);
+ // X448Field.Apm(D, C, B, E);
+ X448Field.Add(D, C, B);
+ X448Field.Sub(D, C, E);
+ X448Field.Carry(B);
+ X448Field.Sub(H, B, H);
+ X448Field.Mul(H, r.z, H);
+ X448Field.Mul(E, r.z, E);
+ X448Field.Mul(F, H, r.x);
+ X448Field.Mul(E, G, r.y);
+ X448Field.Mul(F, G, r.z);
+ }
+
+ private static PointExt PointCopy(PointExt p)
+ {
+ PointExt r = new PointExt();
+ X448Field.Copy(p.x, 0, r.x, 0);
+ X448Field.Copy(p.y, 0, r.y, 0);
+ X448Field.Copy(p.z, 0, r.z, 0);
+ return r;
+ }
+
+ private static void PointDouble(PointExt r)
+ {
+ uint[] B = X448Field.Create();
+ uint[] C = X448Field.Create();
+ uint[] D = X448Field.Create();
+ uint[] E = X448Field.Create();
+ uint[] H = X448Field.Create();
+ uint[] J = X448Field.Create();
+
+ X448Field.Add(r.x, r.y, B);
+ X448Field.Sqr(B, B);
+ X448Field.Sqr(r.x, C);
+ X448Field.Sqr(r.y, D);
+ X448Field.Add(C, D, E);
+ X448Field.Carry(E);
+ X448Field.Sqr(r.z, H);
+ X448Field.Add(H, H, H);
+ X448Field.Carry(H);
+ X448Field.Sub(E, H, J);
+ X448Field.Sub(B, E, B);
+ X448Field.Sub(C, D, C);
+ X448Field.Mul(B, J, r.x);
+ X448Field.Mul(E, C, r.y);
+ X448Field.Mul(E, J, r.z);
+ }
+
+ private static void PointExtendXY(PointExt p)
+ {
+ X448Field.One(p.z);
+ }
+
+ private static void PointLookup(int block, int index, PointPrecomp p)
+ {
+ Debug.Assert(0 <= block && block < PrecompBlocks);
+ Debug.Assert(0 <= index && index < PrecompPoints);
+
+ int off = block * PrecompPoints * 2 * X448Field.Size;
+
+ for (int i = 0; i < PrecompPoints; ++i)
+ {
+ int mask = ((i ^ index) - 1) >> 31;
+ Nat.CMov(X448Field.Size, mask, precompBase, off, p.x, 0); off += X448Field.Size;
+ Nat.CMov(X448Field.Size, mask, precompBase, off, p.y, 0); off += X448Field.Size;
+ }
+ }
+
+ private static PointExt[] PointPrecompVar(PointExt p, int count)
+ {
+ Debug.Assert(count > 0);
+
+ PointExt d = PointCopy(p);
+ PointDouble(d);
+
+ PointExt[] table = new PointExt[count];
+ table[0] = PointCopy(p);
+ for (int i = 1; i < count; ++i)
+ {
+ table[i] = PointCopy(table[i - 1]);
+ PointAddVar(false, d, table[i]);
+ }
+ return table;
+ }
+
+ private static void PointSetNeutral(PointExt p)
+ {
+ X448Field.Zero(p.x);
+ X448Field.One(p.y);
+ X448Field.One(p.z);
+ }
+
+ [MethodImpl(MethodImplOptions.Synchronized)]
+ public static void Precompute()
+ {
+ if (precompBase != null)
+ {
+ return;
+ }
+
+ PointExt p = new PointExt();
+ X448Field.Copy(B_x, 0, p.x, 0);
+ X448Field.Copy(B_y, 0, p.y, 0);
+ PointExtendXY(p);
+
+ precompBaseTable = PointPrecompVar(p, 1 << (WnafWidthBase - 2));
+
+ precompBase = new uint[PrecompBlocks * PrecompPoints * 2 * X448Field.Size];
+
+ int off = 0;
+ for (int b = 0; b < PrecompBlocks; ++b)
+ {
+ PointExt[] ds = new PointExt[PrecompTeeth];
+
+ PointExt sum = new PointExt();
+ PointSetNeutral(sum);
+
+ for (int t = 0; t < PrecompTeeth; ++t)
+ {
+ PointAddVar(true, p, sum);
+ PointDouble(p);
+
+ ds[t] = PointCopy(p);
+
+ for (int s = 1; s < PrecompSpacing; ++s)
+ {
+ PointDouble(p);
+ }
+ }
+
+ PointExt[] points = new PointExt[PrecompPoints];
+ int k = 0;
+ points[k++] = sum;
+
+ for (int t = 0; t < (PrecompTeeth - 1); ++t)
+ {
+ int size = 1 << t;
+ for (int j = 0; j < size; ++j, ++k)
+ {
+ points[k] = PointCopy(points[k - size]);
+ PointAddVar(false, ds[t], points[k]);
+ }
+ }
+
+ Debug.Assert(k == PrecompPoints);
+
+ for (int i = 0; i < PrecompPoints; ++i)
+ {
+ PointExt q = points[i];
+ // TODO[ed448] Batch inversion
+ X448Field.Inv(q.z, q.z);
+ X448Field.Mul(q.x, q.z, q.x);
+ X448Field.Mul(q.y, q.z, q.y);
+
+ // X448Field.Normalize(q.x);
+ // X448Field.Normalize(q.y);
+
+ X448Field.Copy(q.x, 0, precompBase, off); off += X448Field.Size;
+ X448Field.Copy(q.y, 0, precompBase, off); off += X448Field.Size;
+ }
+ }
+
+ Debug.Assert(off == precompBase.Length);
+ }
+
+ private static void PruneScalar(byte[] n, int nOff, byte[] r)
+ {
+ Array.Copy(n, nOff, r, 0, ScalarBytes);
+
+ r[0] &= 0xFC;
+ r[ScalarBytes - 2] |= 0x80;
+ r[ScalarBytes - 1] &= 0x00;
+ }
+
+ private static byte[] ReduceScalar(byte[] n)
+ {
+ ulong x00 = Decode32(n, 0); // x00:32/--
+ ulong x01 = (Decode24(n, 4) << 4); // x01:28/--
+ ulong x02 = Decode32(n, 7); // x02:32/--
+ ulong x03 = (Decode24(n, 11) << 4); // x03:28/--
+ ulong x04 = Decode32(n, 14); // x04:32/--
+ ulong x05 = (Decode24(n, 18) << 4); // x05:28/--
+ ulong x06 = Decode32(n, 21); // x06:32/--
+ ulong x07 = (Decode24(n, 25) << 4); // x07:28/--
+ ulong x08 = Decode32(n, 28); // x08:32/--
+ ulong x09 = (Decode24(n, 32) << 4); // x09:28/--
+ ulong x10 = Decode32(n, 35); // x10:32/--
+ ulong x11 = (Decode24(n, 39) << 4); // x11:28/--
+ ulong x12 = Decode32(n, 42); // x12:32/--
+ ulong x13 = (Decode24(n, 46) << 4); // x13:28/--
+ ulong x14 = Decode32(n, 49); // x14:32/--
+ ulong x15 = (Decode24(n, 53) << 4); // x15:28/--
+ ulong x16 = Decode32(n, 56); // x16:32/--
+ ulong x17 = (Decode24(n, 60) << 4); // x17:28/--
+ ulong x18 = Decode32(n, 63); // x18:32/--
+ ulong x19 = (Decode24(n, 67) << 4); // x19:28/--
+ ulong x20 = Decode32(n, 70); // x20:32/--
+ ulong x21 = (Decode24(n, 74) << 4); // x21:28/--
+ ulong x22 = Decode32(n, 77); // x22:32/--
+ ulong x23 = (Decode24(n, 81) << 4); // x23:28/--
+ ulong x24 = Decode32(n, 84); // x24:32/--
+ ulong x25 = (Decode24(n, 88) << 4); // x25:28/--
+ ulong x26 = Decode32(n, 91); // x26:32/--
+ ulong x27 = (Decode24(n, 95) << 4); // x27:28/--
+ ulong x28 = Decode32(n, 98); // x28:32/--
+ ulong x29 = (Decode24(n, 102) << 4); // x29:28/--
+ ulong x30 = Decode32(n, 105); // x30:32/--
+ ulong x31 = (Decode24(n, 109) << 4); // x31:28/--
+ ulong x32 = Decode16(n, 112); // x32:16/--
+
+ // x32 += (x31 >> 28); x31 &= M28UL;
+ x16 += x32 * L4_0; // x16:42/--
+ x17 += x32 * L4_1; // x17:41/28
+ x18 += x32 * L4_2; // x18:43/42
+ x19 += x32 * L4_3; // x19:44/28
+ x20 += x32 * L4_4; // x20:43/--
+ x21 += x32 * L4_5; // x21:44/28
+ x22 += x32 * L4_6; // x22:43/41
+ x23 += x32 * L4_7; // x23:45/41
+
+ x31 += (x30 >> 28); x30 &= M28UL; // x31:28/--, x30:28/--
+ x15 += x31 * L4_0; // x15:54/--
+ x16 += x31 * L4_1; // x16:53/42
+ x17 += x31 * L4_2; // x17:55/54
+ x18 += x31 * L4_3; // x18:56/44
+ x19 += x31 * L4_4; // x19:55/--
+ x20 += x31 * L4_5; // x20:56/43
+ x21 += x31 * L4_6; // x21:55/53
+ x22 += x31 * L4_7; // x22:57/53
+
+ // x30 += (x29 >> 28); x29 &= M28UL;
+ x14 += x30 * L4_0; // x14:54/--
+ x15 += x30 * L4_1; // x15:54/53
+ x16 += x30 * L4_2; // x16:56/--
+ x17 += x30 * L4_3; // x17:57/--
+ x18 += x30 * L4_4; // x18:56/55
+ x19 += x30 * L4_5; // x19:56/55
+ x20 += x30 * L4_6; // x20:57/--
+ x21 += x30 * L4_7; // x21:57/56
+
+ x29 += (x28 >> 28); x28 &= M28UL; // x29:28/--, x28:28/--
+ x13 += x29 * L4_0; // x13:54/--
+ x14 += x29 * L4_1; // x14:54/53
+ x15 += x29 * L4_2; // x15:56/--
+ x16 += x29 * L4_3; // x16:57/--
+ x17 += x29 * L4_4; // x17:57/55
+ x18 += x29 * L4_5; // x18:57/55
+ x19 += x29 * L4_6; // x19:57/52
+ x20 += x29 * L4_7; // x20:58/52
+
+ // x28 += (x27 >> 28); x27 &= M28UL;
+ x12 += x28 * L4_0; // x12:54/--
+ x13 += x28 * L4_1; // x13:54/53
+ x14 += x28 * L4_2; // x14:56/--
+ x15 += x28 * L4_3; // x15:57/--
+ x16 += x28 * L4_4; // x16:57/55
+ x17 += x28 * L4_5; // x17:58/--
+ x18 += x28 * L4_6; // x18:58/--
+ x19 += x28 * L4_7; // x19:58/53
+
+ x27 += (x26 >> 28); x26 &= M28UL; // x27:28/--, x26:28/--
+ x11 += x27 * L4_0; // x11:54/--
+ x12 += x27 * L4_1; // x12:54/53
+ x13 += x27 * L4_2; // x13:56/--
+ x14 += x27 * L4_3; // x14:57/--
+ x15 += x27 * L4_4; // x15:57/55
+ x16 += x27 * L4_5; // x16:58/--
+ x17 += x27 * L4_6; // x17:58/56
+ x18 += x27 * L4_7; // x18:59/--
+
+ // x26 += (x25 >> 28); x25 &= M28UL;
+ x10 += x26 * L4_0; // x10:54/--
+ x11 += x26 * L4_1; // x11:54/53
+ x12 += x26 * L4_2; // x12:56/--
+ x13 += x26 * L4_3; // x13:57/--
+ x14 += x26 * L4_4; // x14:57/55
+ x15 += x26 * L4_5; // x15:58/--
+ x16 += x26 * L4_6; // x16:58/56
+ x17 += x26 * L4_7; // x17:59/--
+
+ x25 += (x24 >> 28); x24 &= M28UL; // x25:28/--, x24:28/--
+ x09 += x25 * L4_0; // x09:54/--
+ x10 += x25 * L4_1; // x10:54/53
+ x11 += x25 * L4_2; // x11:56/--
+ x12 += x25 * L4_3; // x12:57/--
+ x13 += x25 * L4_4; // x13:57/55
+ x14 += x25 * L4_5; // x14:58/--
+ x15 += x25 * L4_6; // x15:58/56
+ x16 += x25 * L4_7; // x16:59/--
+
+ x21 += (x20 >> 28); x20 &= M28UL; // x21:58/--, x20:28/--
+ x22 += (x21 >> 28); x21 &= M28UL; // x22:57/54, x21:28/--
+ x23 += (x22 >> 28); x22 &= M28UL; // x23:45/42, x22:28/--
+ x24 += (x23 >> 28); x23 &= M28UL; // x24:28/18, x23:28/--
+
+ x08 += x24 * L4_0; // x08:54/--
+ x09 += x24 * L4_1; // x09:55/--
+ x10 += x24 * L4_2; // x10:56/46
+ x11 += x24 * L4_3; // x11:57/46
+ x12 += x24 * L4_4; // x12:57/55
+ x13 += x24 * L4_5; // x13:58/--
+ x14 += x24 * L4_6; // x14:58/56
+ x15 += x24 * L4_7; // x15:59/--
+
+ x07 += x23 * L4_0; // x07:54/--
+ x08 += x23 * L4_1; // x08:54/53
+ x09 += x23 * L4_2; // x09:56/53
+ x10 += x23 * L4_3; // x10:57/46
+ x11 += x23 * L4_4; // x11:57/55
+ x12 += x23 * L4_5; // x12:58/--
+ x13 += x23 * L4_6; // x13:58/56
+ x14 += x23 * L4_7; // x14:59/--
+
+ x06 += x22 * L4_0; // x06:54/--
+ x07 += x22 * L4_1; // x07:54/53
+ x08 += x22 * L4_2; // x08:56/--
+ x09 += x22 * L4_3; // x09:57/53
+ x10 += x22 * L4_4; // x10:57/55
+ x11 += x22 * L4_5; // x11:58/--
+ x12 += x22 * L4_6; // x12:58/56
+ x13 += x22 * L4_7; // x13:59/--
+
+ x18 += (x17 >> 28); x17 &= M28UL; // x18:59/31, x17:28/--
+ x19 += (x18 >> 28); x18 &= M28UL; // x19:58/54, x18:28/--
+ x20 += (x19 >> 28); x19 &= M28UL; // x20:30/29, x19:28/--
+ x21 += (x20 >> 28); x20 &= M28UL; // x21:28/03, x20:28/--
+
+ x05 += x21 * L4_0; // x05:54/--
+ x06 += x21 * L4_1; // x06:55/--
+ x07 += x21 * L4_2; // x07:56/31
+ x08 += x21 * L4_3; // x08:57/31
+ x09 += x21 * L4_4; // x09:57/56
+ x10 += x21 * L4_5; // x10:58/--
+ x11 += x21 * L4_6; // x11:58/56
+ x12 += x21 * L4_7; // x12:59/--
+
+ x04 += x20 * L4_0; // x04:54/--
+ x05 += x20 * L4_1; // x05:54/53
+ x06 += x20 * L4_2; // x06:56/53
+ x07 += x20 * L4_3; // x07:57/31
+ x08 += x20 * L4_4; // x08:57/55
+ x09 += x20 * L4_5; // x09:58/--
+ x10 += x20 * L4_6; // x10:58/56
+ x11 += x20 * L4_7; // x11:59/--
+
+ x03 += x19 * L4_0; // x03:54/--
+ x04 += x19 * L4_1; // x04:54/53
+ x05 += x19 * L4_2; // x05:56/--
+ x06 += x19 * L4_3; // x06:57/53
+ x07 += x19 * L4_4; // x07:57/55
+ x08 += x19 * L4_5; // x08:58/--
+ x09 += x19 * L4_6; // x09:58/56
+ x10 += x19 * L4_7; // x10:59/--
+
+ x15 += (x14 >> 28); x14 &= M28UL; // x15:59/31, x14:28/--
+ x16 += (x15 >> 28); x15 &= M28UL; // x16:59/32, x15:28/--
+ x17 += (x16 >> 28); x16 &= M28UL; // x17:31/29, x16:28/--
+ x18 += (x17 >> 28); x17 &= M28UL; // x18:28/04, x17:28/--
+
+ x02 += x18 * L4_0; // x02:54/--
+ x03 += x18 * L4_1; // x03:55/--
+ x04 += x18 * L4_2; // x04:56/32
+ x05 += x18 * L4_3; // x05:57/32
+ x06 += x18 * L4_4; // x06:57/56
+ x07 += x18 * L4_5; // x07:58/--
+ x08 += x18 * L4_6; // x08:58/56
+ x09 += x18 * L4_7; // x09:59/--
+
+ x01 += x17 * L4_0; // x01:54/--
+ x02 += x17 * L4_1; // x02:54/53
+ x03 += x17 * L4_2; // x03:56/53
+ x04 += x17 * L4_3; // x04:57/32
+ x05 += x17 * L4_4; // x05:57/55
+ x06 += x17 * L4_5; // x06:58/--
+ x07 += x17 * L4_6; // x07:58/56
+ x08 += x17 * L4_7; // x08:59/--
+
+ x16 *= 4;
+ x16 += (x15 >> 26); x15 &= M26UL;
+ x16 += 1; // x16:30/01
+
+ x00 += x16 * L_0;
+ x01 += x16 * L_1;
+ x02 += x16 * L_2;
+ x03 += x16 * L_3;
+ x04 += x16 * L_4;
+ x05 += x16 * L_5;
+ x06 += x16 * L_6;
+ x07 += x16 * L_7;
+
+ x01 += (x00 >> 28); x00 &= M28UL;
+ x02 += (x01 >> 28); x01 &= M28UL;
+ x03 += (x02 >> 28); x02 &= M28UL;
+ x04 += (x03 >> 28); x03 &= M28UL;
+ x05 += (x04 >> 28); x04 &= M28UL;
+ x06 += (x05 >> 28); x05 &= M28UL;
+ x07 += (x06 >> 28); x06 &= M28UL;
+ x08 += (x07 >> 28); x07 &= M28UL;
+ x09 += (x08 >> 28); x08 &= M28UL;
+ x10 += (x09 >> 28); x09 &= M28UL;
+ x11 += (x10 >> 28); x10 &= M28UL;
+ x12 += (x11 >> 28); x11 &= M28UL;
+ x13 += (x12 >> 28); x12 &= M28UL;
+ x14 += (x13 >> 28); x13 &= M28UL;
+ x15 += (x14 >> 28); x14 &= M28UL;
+ x16 = (x15 >> 26); x15 &= M26UL;
+
+ x16 -= 1;
+
+ Debug.Assert(x16 == 0UL || x16 == ulong.MaxValue);
+
+ x00 -= x16 & L_0;
+ x01 -= x16 & L_1;
+ x02 -= x16 & L_2;
+ x03 -= x16 & L_3;
+ x04 -= x16 & L_4;
+ x05 -= x16 & L_5;
+ x06 -= x16 & L_6;
+ x07 -= x16 & L_7;
+
+ x01 += (ulong)((long)x00 >> 28); x00 &= M28UL;
+ x02 += (ulong)((long)x01 >> 28); x01 &= M28UL;
+ x03 += (ulong)((long)x02 >> 28); x02 &= M28UL;
+ x04 += (ulong)((long)x03 >> 28); x03 &= M28UL;
+ x05 += (ulong)((long)x04 >> 28); x04 &= M28UL;
+ x06 += (ulong)((long)x05 >> 28); x05 &= M28UL;
+ x07 += (ulong)((long)x06 >> 28); x06 &= M28UL;
+ x08 += (ulong)((long)x07 >> 28); x07 &= M28UL;
+ x09 += (ulong)((long)x08 >> 28); x08 &= M28UL;
+ x10 += (ulong)((long)x09 >> 28); x09 &= M28UL;
+ x11 += (ulong)((long)x10 >> 28); x10 &= M28UL;
+ x12 += (ulong)((long)x11 >> 28); x11 &= M28UL;
+ x13 += (ulong)((long)x12 >> 28); x12 &= M28UL;
+ x14 += (ulong)((long)x13 >> 28); x13 &= M28UL;
+ x15 += (ulong)((long)x14 >> 28); x14 &= M28UL;
+
+ Debug.Assert(x15 >> 26 == 0UL);
+
+ byte[] r = new byte[ScalarBytes];
+ Encode56(x00 | (x01 << 28), r, 0);
+ Encode56(x02 | (x03 << 28), r, 7);
+ Encode56(x04 | (x05 << 28), r, 14);
+ Encode56(x06 | (x07 << 28), r, 21);
+ Encode56(x08 | (x09 << 28), r, 28);
+ Encode56(x10 | (x11 << 28), r, 35);
+ Encode56(x12 | (x13 << 28), r, 42);
+ Encode56(x14 | (x15 << 28), r, 49);
+ // r[ScalarBytes - 1] = 0;
+ return r;
+ }
+
+ private static void ScalarMultBase(byte[] k, PointExt r)
+ {
+ Precompute();
+
+ PointSetNeutral(r);
+
+ uint[] n = new uint[ScalarUints + 1];
+ DecodeScalar(k, 0, n);
+
+ // Recode the scalar into signed-digit form
+ {
+ n[ScalarUints] = 4U + Nat.CAdd(ScalarUints, ~(int)n[0] & 1, n, L, n);
+ uint c = Nat.ShiftDownBit(n.Length, n, 0);
+ Debug.Assert(c == (1U << 31));
+ }
+
+ PointPrecomp p = new PointPrecomp();
+
+ int cOff = PrecompSpacing - 1;
+ for (;;)
+ {
+ int tPos = cOff;
+
+ for (int b = 0; b < PrecompBlocks; ++b)
+ {
+ uint w = 0;
+ for (int t = 0; t < PrecompTeeth; ++t)
+ {
+ uint tBit = (n[tPos >> 5] >> (tPos & 0x1F)) & 1U;
+ w |= tBit << t;
+ tPos += PrecompSpacing;
+ }
+
+ int sign = (int)(w >> (PrecompTeeth - 1)) & 1;
+ int abs = ((int)w ^ -sign) & PrecompMask;
+
+ Debug.Assert(sign == 0 || sign == 1);
+ Debug.Assert(0 <= abs && abs < PrecompPoints);
+
+ PointLookup(b, abs, p);
+
+ X448Field.CNegate(sign, p.x);
+
+ PointAddPrecomp(p, r);
+ }
+
+ if (--cOff < 0)
+ {
+ break;
+ }
+
+ PointDouble(r);
+ }
+ }
+
+ private static void ScalarMultBaseEncoded(byte[] k, byte[] r, int rOff)
+ {
+ PointExt p = new PointExt();
+ ScalarMultBase(k, p);
+ EncodePoint(p, r, rOff);
+ }
+
+ private static void ScalarMultStraussVar(uint[] nb, uint[] np, PointExt p, PointExt r)
+ {
+ Precompute();
+
+ int width = 5;
+
+ sbyte[] ws_b = GetWnaf(nb, WnafWidthBase);
+ sbyte[] ws_p = GetWnaf(np, width);
+
+ PointExt[] tp = PointPrecompVar(p, 1 << (width - 2));
+
+ PointSetNeutral(r);
+
+ int bit = 447;
+ while (bit > 0 && (ws_b[bit] | ws_p[bit]) == 0)
+ {
+ --bit;
+ }
+
+ for (;;)
+ {
+ int wb = ws_b[bit];
+ if (wb != 0)
+ {
+ int sign = wb >> 31;
+ int index = (wb ^ sign) >> 1;
+
+ PointAddVar((sign != 0), precompBaseTable[index], r);
+ }
+
+ int wp = ws_p[bit];
+ if (wp != 0)
+ {
+ int sign = wp >> 31;
+ int index = (wp ^ sign) >> 1;
+
+ PointAddVar((sign != 0), tp[index], r);
+ }
+
+ if (--bit < 0)
+ {
+ break;
+ }
+
+ PointDouble(r);
+ }
+ }
+
+ public static void Sign(byte[] sk, int skOff, byte[] ctx, byte[] m, int mOff, int mLen, byte[] sig, int sigOff)
+ {
+ if (!CheckContextVar(ctx))
+ {
+ throw new ArgumentException("ctx");
+ }
+
+ ShakeDigest d = new ShakeDigest(256);
+ byte[] h = new byte[ScalarBytes * 2];
+
+ d.BlockUpdate(sk, skOff, SecretKeySize);
+ d.DoFinal(h, 0, h.Length);
+
+ byte[] s = new byte[ScalarBytes];
+ PruneScalar(h, 0, s);
+
+ byte[] pk = new byte[PointBytes];
+ ScalarMultBaseEncoded(s, pk, 0);
+
+ ImplSign(d, h, s, pk, 0, ctx, m, mOff, mLen, sig, sigOff);
+ }
+
+ public static void Sign(byte[] sk, int skOff, byte[] pk, int pkOff, byte[] ctx, byte[] m, int mOff, int mLen, byte[] sig, int sigOff)
+ {
+ if (!CheckContextVar(ctx))
+ {
+ throw new ArgumentException("ctx");
+ }
+
+ ShakeDigest d = new ShakeDigest(256);
+ byte[] h = new byte[ScalarBytes * 2];
+
+ d.BlockUpdate(sk, skOff, SecretKeySize);
+ d.DoFinal(h, 0, h.Length);
+
+ byte[] s = new byte[ScalarBytes];
+ PruneScalar(h, 0, s);
+
+ ImplSign(d, h, s, pk, pkOff, ctx, m, mOff, mLen, sig, sigOff);
+ }
+
+ public static bool Verify(byte[] sig, int sigOff, byte[] pk, int pkOff, byte[] ctx, byte[] m, int mOff, int mLen)
+ {
+ if (!CheckContextVar(ctx))
+ {
+ throw new ArgumentException("ctx");
+ }
+
+ byte[] R = Arrays.CopyOfRange(sig, sigOff, sigOff + PointBytes);
+ byte[] S = Arrays.CopyOfRange(sig, sigOff + PointBytes, sigOff + SignatureSize);
+
+ if (!CheckPointVar(R))
+ {
+ return false;
+ }
+ if (!CheckScalarVar(S))
+ {
+ return false;
+ }
+
+ PointExt pA = new PointExt();
+ if (!DecodePointVar(pk, pkOff, true, pA))
+ {
+ return false;
+ }
+
+ byte phflag = 0x00;
+
+ ShakeDigest d = new ShakeDigest(256);
+ byte[] h = new byte[ScalarBytes * 2];
+
+ Dom4(d, phflag, ctx);
+ d.BlockUpdate(R, 0, PointBytes);
+ d.BlockUpdate(pk, pkOff, PointBytes);
+ d.BlockUpdate(m, mOff, mLen);
+ d.DoFinal(h, 0, h.Length);
+
+ byte[] k = ReduceScalar(h);
+
+ uint[] nS = new uint[ScalarUints];
+ DecodeScalar(S, 0, nS);
+
+ uint[] nA = new uint[ScalarUints];
+ DecodeScalar(k, 0, nA);
+
+ PointExt pR = new PointExt();
+ ScalarMultStraussVar(nS, nA, pA, pR);
+
+ byte[] check = new byte[PointBytes];
+ EncodePoint(pR, check, 0);
+
+ return Arrays.AreEqual(check, R);
+ }
+ }
+}
diff --git a/crypto/src/math/raw/Interleave.cs b/crypto/src/math/raw/Interleave.cs
index d21840644..591ba3f15 100644
--- a/crypto/src/math/raw/Interleave.cs
+++ b/crypto/src/math/raw/Interleave.cs
@@ -6,6 +6,7 @@ namespace Org.BouncyCastle.Math.Raw
{
private const ulong M32 = 0x55555555UL;
private const ulong M64 = 0x5555555555555555UL;
+ private const ulong M64R = 0xAAAAAAAAAAAAAAAAUL;
/*
* This expands 8 bit indices into 16 bit contents (high bit 14), by inserting 0s between bits.
@@ -92,6 +93,65 @@ namespace Org.BouncyCastle.Math.Raw
z[zOff + 1] = (x >> 1) & M64;
}
+ internal static void Expand64To128Rev(ulong x, ulong[] z, int zOff)
+ {
+ // "shuffle" low half to even bits and high half to odd bits
+ ulong t;
+ t = (x ^ (x >> 16)) & 0x00000000FFFF0000UL; x ^= (t ^ (t << 16));
+ t = (x ^ (x >> 8)) & 0x0000FF000000FF00UL; x ^= (t ^ (t << 8));
+ t = (x ^ (x >> 4)) & 0x00F000F000F000F0UL; x ^= (t ^ (t << 4));
+ t = (x ^ (x >> 2)) & 0x0C0C0C0C0C0C0C0CUL; x ^= (t ^ (t << 2));
+ t = (x ^ (x >> 1)) & 0x2222222222222222UL; x ^= (t ^ (t << 1));
+
+ z[zOff] = (x ) & M64R;
+ z[zOff + 1] = (x << 1) & M64R;
+ }
+
+ internal static uint Shuffle(uint x)
+ {
+ // "shuffle" low half to even bits and high half to odd bits
+ uint t;
+ t = (x ^ (x >> 8)) & 0x0000FF00U; x ^= (t ^ (t << 8));
+ t = (x ^ (x >> 4)) & 0x00F000F0U; x ^= (t ^ (t << 4));
+ t = (x ^ (x >> 2)) & 0x0C0C0C0CU; x ^= (t ^ (t << 2));
+ t = (x ^ (x >> 1)) & 0x22222222U; x ^= (t ^ (t << 1));
+ return x;
+ }
+
+ internal static ulong Shuffle(ulong x)
+ {
+ // "shuffle" low half to even bits and high half to odd bits
+ ulong t;
+ t = (x ^ (x >> 16)) & 0x00000000FFFF0000UL; x ^= (t ^ (t << 16));
+ t = (x ^ (x >> 8)) & 0x0000FF000000FF00UL; x ^= (t ^ (t << 8));
+ t = (x ^ (x >> 4)) & 0x00F000F000F000F0UL; x ^= (t ^ (t << 4));
+ t = (x ^ (x >> 2)) & 0x0C0C0C0C0C0C0C0CUL; x ^= (t ^ (t << 2));
+ t = (x ^ (x >> 1)) & 0x2222222222222222UL; x ^= (t ^ (t << 1));
+ return x;
+ }
+
+ internal static uint Shuffle2(uint x)
+ {
+ // "shuffle" (twice) low half to even bits and high half to odd bits
+ uint t;
+ t = (x ^ (x >> 7)) & 0x00AA00AAU; x ^= (t ^ (t << 7));
+ t = (x ^ (x >> 14)) & 0x0000CCCCU; x ^= (t ^ (t << 14));
+ t = (x ^ (x >> 4)) & 0x00F000F0U; x ^= (t ^ (t << 4));
+ t = (x ^ (x >> 8)) & 0x0000FF00U; x ^= (t ^ (t << 8));
+ return x;
+ }
+
+ internal static uint Unshuffle(uint x)
+ {
+ // "unshuffle" even bits to low half and odd bits to high half
+ uint t;
+ t = (x ^ (x >> 1)) & 0x22222222U; x ^= (t ^ (t << 1));
+ t = (x ^ (x >> 2)) & 0x0C0C0C0CU; x ^= (t ^ (t << 2));
+ t = (x ^ (x >> 4)) & 0x00F000F0U; x ^= (t ^ (t << 4));
+ t = (x ^ (x >> 8)) & 0x0000FF00U; x ^= (t ^ (t << 8));
+ return x;
+ }
+
internal static ulong Unshuffle(ulong x)
{
// "unshuffle" even bits to low half and odd bits to high half
@@ -103,5 +163,16 @@ namespace Org.BouncyCastle.Math.Raw
t = (x ^ (x >> 16)) & 0x00000000FFFF0000UL; x ^= (t ^ (t << 16));
return x;
}
+
+ internal static uint Unshuffle2(uint x)
+ {
+ // "unshuffle" (twice) even bits to low half and odd bits to high half
+ uint t;
+ t = (x ^ (x >> 8)) & 0x0000FF00U; x ^= (t ^ (t << 8));
+ t = (x ^ (x >> 4)) & 0x00F000F0U; x ^= (t ^ (t << 4));
+ t = (x ^ (x >> 14)) & 0x0000CCCCU; x ^= (t ^ (t << 14));
+ t = (x ^ (x >> 7)) & 0x00AA00AAU; x ^= (t ^ (t << 7));
+ return x;
+ }
}
}
diff --git a/crypto/src/math/raw/Nat.cs b/crypto/src/math/raw/Nat.cs
index cf6516c61..7ca60278a 100644
--- a/crypto/src/math/raw/Nat.cs
+++ b/crypto/src/math/raw/Nat.cs
@@ -195,6 +195,64 @@ namespace Org.BouncyCastle.Math.Raw
return c == 0 ? 0 : IncAt(len, z, zOff, 1);
}
+ public static uint CAdd(int len, int mask, uint[] x, uint[] y, uint[] z)
+ {
+ uint MASK = (uint)-(mask & 1);
+
+ ulong c = 0;
+ for (int i = 0; i < len; ++i)
+ {
+ c += (ulong)x[i] + (y[i] & MASK);
+ z[i] = (uint)c;
+ c >>= 32;
+ }
+ return (uint)c;
+ }
+
+ public static void CMov(int len, int mask, uint[] x, int xOff, uint[] z, int zOff)
+ {
+ uint MASK = (uint)-(mask & 1);
+
+ for (int i = 0; i < len; ++i)
+ {
+ uint z_i = z[zOff + i], diff = z_i ^ x[xOff + i];
+ z_i ^= (diff & MASK);
+ z[zOff + i] = z_i;
+ }
+
+ //uint half = 0x55555555U, rest = half << (-(int)MASK);
+
+ //for (int i = 0; i < len; ++i)
+ //{
+ // uint z_i = z[zOff + i], diff = z_i ^ x[xOff + i];
+ // z_i ^= (diff & half);
+ // z_i ^= (diff & rest);
+ // z[zOff + i] = z_i;
+ //}
+ }
+
+ public static void CMov(int len, int mask, int[] x, int xOff, int[] z, int zOff)
+ {
+ mask = -(mask & 1);
+
+ for (int i = 0; i < len; ++i)
+ {
+ int z_i = z[zOff + i], diff = z_i ^ x[xOff + i];
+ z_i ^= (diff & mask);
+ z[zOff + i] = z_i;
+ }
+
+ //int half = 0x55555555, rest = half << (-mask);
+
+ //for (int i = 0; i < len; ++i)
+ //{
+ // int z_i = z[zOff + i], diff = z_i ^ x[xOff + i];
+ // z_i ^= (diff & half);
+ // z_i ^= (diff & rest);
+ // z[zOff + i] = z_i;
+ //}
+ }
+
public static void Copy(int len, uint[] x, uint[] z)
{
Array.Copy(x, 0, z, 0, len);
@@ -448,6 +506,33 @@ namespace Org.BouncyCastle.Math.Raw
}
}
+ public static uint MulAddTo(int len, uint[] x, uint[] y, uint[] zz)
+ {
+ ulong zc = 0;
+ for (int i = 0; i < len; ++i)
+ {
+ ulong c = MulWordAddTo(len, x[i], y, 0, zz, i) & M;
+ c += zc + (zz[i + len] & M);
+ zz[i + len] = (uint)c;
+ zc = c >> 32;
+ }
+ return (uint)zc;
+ }
+
+ public static uint MulAddTo(int len, uint[] x, int xOff, uint[] y, int yOff, uint[] zz, int zzOff)
+ {
+ ulong zc = 0;
+ for (int i = 0; i < len; ++i)
+ {
+ ulong c = MulWordAddTo(len, x[xOff + i], y, yOff, zz, zzOff) & M;
+ c += zc + (zz[zzOff + len] & M);
+ zz[zzOff + len] = (uint)c;
+ zc = c >> 32;
+ ++zzOff;
+ }
+ return (uint)zc;
+ }
+
public static uint Mul31BothAdd(int len, uint a, uint[] x, uint b, uint[] y, uint[] z, int zOff)
{
ulong c = 0, aVal = (ulong)a, bVal = (ulong)b;
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