diff --git a/crypto/src/math/ec/custom/sec/SecT283Field.cs b/crypto/src/math/ec/custom/sec/SecT283Field.cs
index 903ea02ff..22b7eaaab 100644
--- a/crypto/src/math/ec/custom/sec/SecT283Field.cs
+++ b/crypto/src/math/ec/custom/sec/SecT283Field.cs
@@ -10,6 +10,8 @@ namespace Org.BouncyCastle.Math.EC.Custom.Sec
private const ulong M27 = ulong.MaxValue >> 37;
private const ulong M57 = ulong.MaxValue >> 7;
+ private static readonly ulong[] ROOT_Z = new ulong[]{ 0x0C30C30C30C30808UL, 0x30C30C30C30C30C3UL, 0x820820820820830CUL, 0x0820820820820820UL, 0x2082082UL };
+
public static void Add(ulong[] x, ulong[] y, ulong[] z)
{
z[0] = x[0] ^ y[0];
@@ -129,6 +131,30 @@ namespace Org.BouncyCastle.Math.EC.Custom.Sec
z[zOff + 4] = z4 & M27;
}
+ public static void Sqrt(ulong[] x, ulong[] z)
+ {
+ ulong[] odd = Nat320.Create64();
+
+ ulong u0, u1;
+ u0 = Interleave.Unshuffle(x[0]); u1 = Interleave.Unshuffle(x[1]);
+ ulong e0 = (u0 & 0x00000000FFFFFFFFUL) | (u1 << 32);
+ odd[0] = (u0 >> 32) | (u1 & 0xFFFFFFFF00000000UL);
+
+ u0 = Interleave.Unshuffle(x[2]); u1 = Interleave.Unshuffle(x[3]);
+ ulong e1 = (u0 & 0x00000000FFFFFFFFUL) | (u1 << 32);
+ odd[1] = (u0 >> 32) | (u1 & 0xFFFFFFFF00000000UL);
+
+ u0 = Interleave.Unshuffle(x[4]);
+ ulong e2 = (u0 & 0x00000000FFFFFFFFUL);
+ odd[2] = (u0 >> 32);
+
+ Multiply(odd, ROOT_Z, z);
+
+ z[0] ^= e0;
+ z[1] ^= e1;
+ z[2] ^= e2;
+ }
+
public static void Square(ulong[] x, ulong[] z)
{
ulong[] tt = Nat.Create64(9);
@@ -158,6 +184,12 @@ namespace Org.BouncyCastle.Math.EC.Custom.Sec
}
}
+ public static uint Trace(ulong[] x)
+ {
+ // Non-zero-trace bits: 0, 271
+ return (uint)(x[0] ^ (x[4] >> 15)) & 1U;
+ }
+
protected static void ImplCompactExt(ulong[] zz)
{
ulong z0 = zz[0], z1 = zz[1], z2 = zz[2], z3 = zz[3], z4 = zz[4];
|