cryptographer.cs

ecc算法 DiffieHellmanMerkle c#实现

using System;
using System.Collections.Generic;
using System.Text;
using DiffieHellmanMerkle;
using System.IO;
using System.Security.Cryptography;

namespace TestEllipticCurveDiffieHellman
{
    public class Cryptographer
    {
        private byte[] _externalPublicKey;
        private byte[] _secretKey;
        private byte[] _cipherText;
        private byte[] _IVByteArray = Encoding.Unicode.GetBytes("initialV");

        private ECDiffieHellmanMerkle myECDH;

        public byte[] ExternalPublicKey
        {
            get { return _externalPublicKey; }
            set { _externalPublicKey = value; }
        }

        public byte[] PublicKey
        {
            get { return myECDH.PublicKey; }
        }

        public byte[] SecretKey
        {
            get { return _secretKey; }
            set { _secretKey = value; }
        }

        public byte[] CipherText
        {
            get { return _cipherText; }
            set { _cipherText = value; }
        }

        public void CreatePublicPrivateKey()
        {
            myECDH = new ECDiffieHellmanMerkle(ECDHAlgorithm.ECDH_384);
            myECDH.KeyDerivationFunction = ECDHKeyDerivationFunction.HASH;
            myECDH.HashAlgorithm = DerivedKeyHashAlgorithm.SHA256_ALGORITHM;
        }

        public void SendPublicKey(Cryptographer cryptographer)
        {
            cryptographer.ExternalPublicKey = myECDH.PublicKey;
        }

        public void DeriveSecretKey()
        {
            _secretKey = myECDH.RetrieveSecretKey(_externalPublicKey);
        }

        public void EncryptMessage(string secretMessage)
        {
            byte[] SecretMessageByteArray = Encoding.Unicode.GetBytes(secretMessage);
            RijndaelManaged rijndael = new RijndaelManaged();
            ICryptoTransform encryptor = rijndael.CreateEncryptor(_secretKey, _IVByteArray);
            MemoryStream memoryStream = new MemoryStream();
            CryptoStream cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write);
            cryptoStream.Write(SecretMessageByteArray, 0, SecretMessageByteArray.Length);
            cryptoStream.FlushFinalBlock();
            _cipherText = memoryStream.ToArray();
            memoryStream.Close();
            cryptoStream.Close();
        }

        public void SendEncryptedMessage(Cryptographer cryptographer)
        {
            cryptographer.CipherText = _cipherText;
        }

        public string DecryptMessage()
        {
            RijndaelManaged rijndael = new RijndaelManaged();
            ICryptoTransform decryptor = rijndael.CreateDecryptor(_secretKey, _IVByteArray);
            MemoryStream memoryStream = new MemoryStream(_cipherText);
            CryptoStream cryptoStream = new CryptoStream(memoryStream, decryptor, CryptoStreamMode.Read);
            byte[] clearText = new byte[_cipherText.Length];
            int clearTextByteSize = cryptoStream.Read(clearText, 0, clearText.Length);
            memoryStream.Close();
            cryptoStream.Close();
            return Encoding.Unicode.GetString(clearText);
        }
    }
}