Initial Commit

iTechSharp/srcbc/crypto/generators/DHKeyPairGenerator.cs

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+using System;
+
+using Org.BouncyCastle.Crypto.Parameters;
+using Org.BouncyCastle.Math;
+
+namespace Org.BouncyCastle.Crypto.Generators
+{
+    /**
+     * a Diffie-Helman key pair generator.
+     *
+     * This Generates keys consistent for use in the MTI/A0 key agreement protocol
+     * as described in "Handbook of Applied Cryptography", Pages 516-519.
+     */
+    public class DHKeyPairGenerator
+		: IAsymmetricCipherKeyPairGenerator
+    {
+		private DHKeyGenerationParameters param;
+
+		public virtual void Init(
+			KeyGenerationParameters parameters)
+        {
+            this.param = (DHKeyGenerationParameters) parameters;
+        }
+
+		public virtual AsymmetricCipherKeyPair GenerateKeyPair()
+        {
+			DHKeyGeneratorHelper helper = DHKeyGeneratorHelper.Instance;
+			DHParameters dhParams = param.Parameters;
+
+			BigInteger p = dhParams.P;
+			BigInteger x = helper.CalculatePrivate(p, param.Random, dhParams.L);
+			BigInteger y = helper.CalculatePublic(p, dhParams.G, x);
+
+			return new AsymmetricCipherKeyPair(
+                new DHPublicKeyParameters(y, dhParams),
+                new DHPrivateKeyParameters(x, dhParams));
+        }
+    }
+
+}