naming

Esiur.Security.Cryptography/ECDH.cs

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+using System;
+using System.Collections.Generic;
+using System.Security.Cryptography;
+using System.Text;
+using Esiur.Security.Cryptography;
+using Esiur.Data;
+using System.Linq;
+
+namespace Esiur.Security.Cryptography
+{
+    public class ECDH : IKeyExchanger
+    {
+        public ushort Identifier => 1;
+
+        ECDiffieHellman ecdh = ECDiffieHellman.Create(ECCurve.NamedCurves.brainpoolP256r1);
+
+        public byte[] ComputeSharedKey(byte[] key)
+        {
+            var x = key.Clip(0, (uint)key.Length / 2);
+            var y = key.Clip((uint)key.Length / 2, (uint)key.Length / 2);
+
+            ECParameters parameters = new ECParameters
+            {
+                Curve = ECCurve.NamedCurves.brainpoolP256r1,
+                Q = {
+                    X = x,
+                    Y = y, 
+                }
+            };
+
+            byte[] derivedKey;
+            using (ECDiffieHellman peer = ECDiffieHellman.Create(parameters))
+            using (ECDiffieHellmanPublicKey peerPublic = peer.PublicKey)
+            {
+                return derivedKey = ecdh.DeriveKeyMaterial(peerPublic);
+            }
+
+        }
+
+        public byte[] GetPublicKey()
+        {
+            var kp = ecdh.PublicKey.ExportParameters();
+
+            var key = DC.Combine(kp.Q.X, 0, (uint)kp.Q.X.Length, kp.Q.Y, 0, (uint)kp.Q.Y.Length);
+
+            return key;
+        }
+    }
+}