diff options
Diffstat (limited to 'crypto/src/math/ec/rfc7748/X25519Field.cs')
| -rw-r--r-- | crypto/src/math/ec/rfc7748/X25519Field.cs | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/crypto/src/math/ec/rfc7748/X25519Field.cs b/crypto/src/math/ec/rfc7748/X25519Field.cs index b5938e2e7..3a06941dd 100644 --- a/crypto/src/math/ec/rfc7748/X25519Field.cs +++ b/crypto/src/math/ec/rfc7748/X25519Field.cs @@ -14,7 +14,7 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748 private static readonly int[] RootNegOne = { 0x020EA0B0, 0x0386C9D2, 0x00478C4E, 0x0035697F, 0x005E8630, 0x01FBD7A7, 0x0340264F, 0x01F0B2B4, 0x00027E0E, 0x00570649 }; - private X25519Field() {} + protected X25519Field() {} public static void Add(int[] x, int[] y, int[] z) { @@ -67,6 +67,18 @@ namespace Org.BouncyCastle.Math.EC.Rfc7748 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); |