diff options
Diffstat (limited to 'crypto/src/math/ec/custom/sec/SecP256R1Field.cs')
| -rw-r--r-- | crypto/src/math/ec/custom/sec/SecP256R1Field.cs | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/crypto/src/math/ec/custom/sec/SecP256R1Field.cs b/crypto/src/math/ec/custom/sec/SecP256R1Field.cs index 88a13f513..9e366bffe 100644 --- a/crypto/src/math/ec/custom/sec/SecP256R1Field.cs +++ b/crypto/src/math/ec/custom/sec/SecP256R1Field.cs @@ -145,6 +145,42 @@ namespace Org.BouncyCastle.Math.EC.Custom.Sec } } + public static void Reduce32(uint x, uint[] z) + { + long xx08 = x; + + long cc = 0; + cc += (long)z[0] + xx08; + z[0] = (uint)cc; + cc >>= 32; + cc += (long)z[1]; + z[1] = (uint)cc; + cc >>= 32; + cc += (long)z[2]; + z[2] = (uint)cc; + cc >>= 32; + cc += (long)z[3] - xx08; + z[3] = (uint)cc; + cc >>= 32; + cc += (long)z[4]; + z[4] = (uint)cc; + cc >>= 32; + cc += (long)z[5]; + z[5] = (uint)cc; + cc >>= 32; + cc += (long)z[6] - xx08; + z[6] = (uint)cc; + cc >>= 32; + cc += (long)z[7] + xx08; + z[7] = (uint)cc; + cc >>= 32; + + if (cc != 0 || (z[7] == P7 && Nat256.Gte(z, P))) + { + Nat256.Sub(z, P, z); + } + } + public static void Square(uint[] x, uint[] z) { uint[] tt = Nat256.CreateExt(); |