C# CryptoStream.Write方法代码示例

        public static string EncryptString(
            string plainText,
            string passPhrase,
            string saltValue,
            int passwordIterations,
            string initVector,
            int keySize)
        {

            byte[] initVectorBytes = initVector == null ? new byte[16] : Encoding.ASCII.GetBytes(initVector);
            byte[] plainTextBytes = Encoding.UTF8.GetBytes(plainText);
            byte[] keyBytes = GetKeyBytes(passPhrase, saltValue, passwordIterations, keySize);
            RijndaelManaged symmetricKey = new RijndaelManaged();
            symmetricKey.Mode = CipherMode.CBC;
            ICryptoTransform encryptor = symmetricKey.CreateEncryptor(keyBytes, initVectorBytes);
            byte[] cipherTextBytes;
            using (MemoryStream memoryStream = new MemoryStream())
            {
                using (CryptoStream cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write))
                {
                    cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length);
                    cryptoStream.FlushFinalBlock();
                    cipherTextBytes = memoryStream.ToArray();
                }
            }
            string cipherText = Convert.ToBase64String(cipherTextBytes);
            return cipherText;
        }

        public static string Encode(string str, string key)
        {
            DESCryptoServiceProvider provider = new DESCryptoServiceProvider();

            provider.Key = Encoding.ASCII.GetBytes(key.Substring(0, 8));

            provider.IV = Encoding.ASCII.GetBytes(key.Substring(0, 8));

            byte[] bytes = Encoding.UTF8.GetBytes(str);

            MemoryStream stream = new MemoryStream();

            CryptoStream stream2 = new CryptoStream(stream, provider.CreateEncryptor(), CryptoStreamMode.Write);

            stream2.Write(bytes, 0, bytes.Length);

            stream2.FlushFinalBlock();

            StringBuilder builder = new StringBuilder();

            foreach (byte num in stream.ToArray())
            {

                builder.AppendFormat("{0:X2}", num);

            }

            stream.Close();

            return builder.ToString();
        }

 public static string Encrypt(string plainText, string passPhrase)
 {
     byte[] plainTextBytes = Encoding.UTF8.GetBytes(plainText);
     using (PasswordDeriveBytes password = new PasswordDeriveBytes(passPhrase, null))
     {
         byte[] keyBytes = password.GetBytes(keysize / 8);
         using (RijndaelManaged symmetricKey = new RijndaelManaged())
         {
             symmetricKey.Mode = CipherMode.CBC;
             using (ICryptoTransform encryptor = symmetricKey.CreateEncryptor(keyBytes, initVectorBytes))
             {
                 using (MemoryStream memoryStream = new MemoryStream())
                 {
                     using (CryptoStream cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write))
                     {
                         cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length);
                         cryptoStream.FlushFinalBlock();
                         byte[] cipherTextBytes = memoryStream.ToArray();
                         return Convert.ToBase64String(cipherTextBytes);
                     }
                 }
             }
         }
     }
 }

 /// <summary>
 /// 解密
 /// </summary>
 /// <param name="text">要被解密字符</param>
 /// <param name="sKey">密钥</param>
 /// <returns></returns>
 public static string Decrypt(this string text, string sKey)
 {
     var provider = new DESCryptoServiceProvider();
     int num = text.Length / 2;
     byte[] buffer = new byte[num];
     try
     {
         for (int i = 0; i < num; i++)
         {
             int num3 = Convert.ToInt32(text.Substring(i * 2, 2), 0x10);
             buffer[i] = (byte)num3;
         }
     }
     catch
     {
         return string.Empty;
     }
     provider.Key = Encoding.ASCII.GetBytes(FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5").Substring(0, 8));
     provider.IV = Encoding.ASCII.GetBytes(FormsAuthentication.HashPasswordForStoringInConfigFile(sKey, "md5").Substring(0, 8));
     MemoryStream stream = new MemoryStream();
     CryptoStream stream2 = new CryptoStream(stream, provider.CreateDecryptor(), CryptoStreamMode.Write);
     try
     {
         stream2.Write(buffer, 0, buffer.Length);
         stream2.FlushFinalBlock();
     }
     catch
     {
         return string.Empty;
     }
     return Encoding.Default.GetString(stream.ToArray());
 }

        public byte[] AES_Encrypt(byte[] bytesToBeEncrypted, byte[] passwordBytes)
        {
            byte[] encryptedBytes = null;

            // Set your salt here, change it to meet your flavor:
            // The salt bytes must be at least 8 bytes.
            byte[] saltBytes = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8 };

            using (MemoryStream ms = new MemoryStream())
            {
                using (RijndaelManaged AES = new RijndaelManaged())
                {
                    AES.KeySize = 256;
                    AES.BlockSize = 128;

                    var key = new Rfc2898DeriveBytes(passwordBytes, saltBytes, 1000);
                    AES.Key = key.GetBytes(AES.KeySize / 8);
                    AES.IV = key.GetBytes(AES.BlockSize / 8);

                    AES.Mode = CipherMode.CBC;

                    using (var cs = new CryptoStream(ms, AES.CreateEncryptor(), CryptoStreamMode.Write))
                    {
                        cs.Write(bytesToBeEncrypted, 0, bytesToBeEncrypted.Length);
                        cs.Close();
                    }
                    encryptedBytes = ms.ToArray();
                }
            }

            return encryptedBytes;
        }

        // Decrypt a byte array into a byte array using a key and an IV
        public static byte[] Decrypt(byte[] cipherData, byte[] Key, byte[] IV, CipherMode cipherMode, PaddingMode paddingMode)
        {
            // Create a MemoryStream that is going to accept the
            // decrypted bytes
            MemoryStream ms = new MemoryStream();

            // Create a symmetric algorithm.
            // We are going to use Rijndael because it is strong and
            // available on all platforms.
            // You can use other algorithms, to do so substitute the next
            // line with something like
            //     TripleDES alg = TripleDES.Create();

            Rijndael alg = Rijndael.Create();

            // Now set the key and the IV.
            // We need the IV (Initialization Vector) because the algorithm
            // is operating in its default
            // mode called CBC (Cipher Block Chaining). The IV is XORed with
            // the first block (8 byte)
            // of the data after it is decrypted, and then each decrypted
            // block is XORed with the previous
            // cipher block. This is done to make encryption more secure.
            // There is also a mode called ECB which does not need an IV,
            // but it is much less secure.

            alg.Mode = cipherMode;
            alg.Padding = paddingMode;
            alg.Key = Key;
            alg.IV = IV;

            // Create a CryptoStream through which we are going to be
            // pumping our data.
            // CryptoStreamMode.Write means that we are going to be
            // writing data to the stream
            // and the output will be written in the MemoryStream
            // we have provided.

            CryptoStream cs = new CryptoStream(ms,
                alg.CreateDecryptor(), CryptoStreamMode.Write);

            // Write the data and make it do the decryption
            cs.Write(cipherData, 0, cipherData.Length);

            // Close the crypto stream (or do FlushFinalBlock).
            // This will tell it that we have done our decryption
            // and there is no more data coming in,
            // and it is now a good time to remove the padding
            // and finalize the decryption process.

            cs.Close();

            // Now get the decrypted data from the MemoryStream.
            // Some people make a mistake of using GetBuffer() here,
            // which is not the right way.

            byte[] decryptedData = ms.ToArray();

            return decryptedData;
        }

        public static string Encrypt( string strEncryptString, string strEncryptionKey)
        {
            byte[] inputByteArray;

            try
            {
                key = Encoding.UTF8.GetBytes(strEncryptionKey.Substring(0, 8));

                DESCryptoServiceProvider des = new DESCryptoServiceProvider();
                inputByteArray = Encoding.UTF8.GetBytes(strEncryptString);

                MemoryStream ms = new MemoryStream();
                CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(key, IV), CryptoStreamMode.Write);

                cs.Write(inputByteArray, 0, inputByteArray.Length);
                cs.FlushFinalBlock();

                return Convert.ToBase64String(ms.ToArray());
            }
            catch (Exception eX)
            {

                throw eX;
            }
        }

        public byte[] Encrypt(byte[] block)
        {
            ICryptoTransform enc = null;
            Aes.Mode = CipherMode.CBC;
            Aes.Key = key;
            Aes.GenerateIV();
            Console.WriteLine("Key: {0} IV: {1}", CNetwork.ByteArrayToString(Aes.Key), CNetwork.ByteArrayToString(Aes.IV));

            CryptoStream cstream = null;
            MemoryStream mem = null;
            byte[] toEncrypt = null;

            try
            {
                cstream = null;
                mem = new MemoryStream();
                toEncrypt = block;
                enc = Aes.CreateEncryptor();
                cstream = new CryptoStream(mem, enc, CryptoStreamMode.Write);
                cstream.Write(toEncrypt, 0, toEncrypt.Length);
            }
            finally
            {
                if (cstream != null)
                    Aes.Clear();
                cstream.Close();
            }

            Console.WriteLine(CNetwork.ByteArrayToString(mem.ToArray()));

            return mem.ToArray();
        }

 public static string Encrypt(string plainText, string passPhrase)
 {
     // Salt and IV is randomly generated each time, but is preprended to encrypted cipher text
     // so that the same Salt and IV values can be used when decrypting.
     var saltStringBytes = Generate256BitsOfRandomEntropy();
     var ivStringBytes = Generate256BitsOfRandomEntropy();
     var plainTextBytes = Encoding.UTF8.GetBytes(plainText);
     var password = new Rfc2898DeriveBytes(passPhrase, saltStringBytes, DerivationIterations);
     var keyBytes = password.GetBytes(Keysize / 8);
     using (var symmetricKey = new RijndaelManaged())
     {
         symmetricKey.BlockSize = 256;
         symmetricKey.Mode = CipherMode.CBC;
         symmetricKey.Padding = PaddingMode.PKCS7;
         using (var encryptor = symmetricKey.CreateEncryptor(keyBytes, ivStringBytes))
         {
             using (var memoryStream = new MemoryStream())
             {
                 using (var cryptoStream = new CryptoStream(memoryStream, encryptor, CryptoStreamMode.Write))
                 {
                     cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length);
                     cryptoStream.FlushFinalBlock();
                     // Create the final bytes as a concatenation of the random salt bytes, the random iv bytes and the cipher bytes.
                     var cipherTextBytes = saltStringBytes;
                     cipherTextBytes = cipherTextBytes.Concat(ivStringBytes).ToArray();
                     cipherTextBytes = cipherTextBytes.Concat(memoryStream.ToArray()).ToArray();
                     memoryStream.Close();
                     cryptoStream.Close();
                     return Convert.ToBase64String(cipherTextBytes);
                 }
             }
         }
     }
 }

        /// <summary>
        /// 加密方法
        /// </summary>
        /// <param name="pToEncrypt">需要加密字符串</param>
        /// <param name="sKey">密钥</param>
        /// <returns>加密后的字符串</returns>
        public static string Encrypt(string pToEncrypt, string sKey)
        {
            try
            {
                DESCryptoServiceProvider des = new DESCryptoServiceProvider();
                //把字符串放到byte数组中

                //原来使用的UTF8编码，我改成Unicode编码了，不行
                byte[] inputByteArray = Encoding.Default.GetBytes(pToEncrypt);

                //建立加密对象的密钥和偏移量

                //使得输入密码必须输入英文文本
                des.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
                des.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
                MemoryStream ms = new MemoryStream();
                CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(), CryptoStreamMode.Write);

                cs.Write(inputByteArray, 0, inputByteArray.Length);
                cs.FlushFinalBlock();
                StringBuilder ret = new StringBuilder();
                foreach (byte b in ms.ToArray())
                {
                    ret.AppendFormat("{0:X2}", b);
                }
                ret.ToString();
                return ret.ToString();
            }
            catch (Exception ex)
            {

            }

            return "";
        }

        /// <summary>
        /// Encrypt a message using AES in CBC (cipher-block chaining) mode.
        /// </summary>
        /// <param name="plaintext">The message (plaintext) to encrypt</param>
        /// <param name="key">An AES key</param>
        /// <param name="iv">The IV to use or null to use a 0 IV</param>
        /// <param name="addHmac">When set, a SHA256-based HMAC (HMAC256) of 32 bytes using the same key is added to the plaintext
        /// before it is encrypted.</param>
        /// <returns>The ciphertext derived by encrypting the orignal message using AES in CBC mode</returns>
        public static byte[] EncryptAesCbc(byte[] plaintext, byte[] key, byte[] iv = null, bool addHmac = false)
        {
            using (Aes aes =Aes.Create())
//            using (AesCryptoServiceProvider aes = new AesCryptoServiceProvider())
            {
                aes.Key = key;
                if (iv == null)
                    iv = NullIv;
                aes.Mode = CipherMode.CBC;
                aes.IV = iv;

                // Encrypt the message with the key using CBC and InitializationVector=0
                byte[] cipherText;
                using (System.IO.MemoryStream ciphertext = new System.IO.MemoryStream())
                {
                    using (CryptoStream cs = new CryptoStream(ciphertext, aes.CreateEncryptor(), CryptoStreamMode.Write))
                    {
                        cs.Write(plaintext, 0, plaintext.Length);
                        if (addHmac)
                        {
                            byte[] hmac = new HMACSHA256(key).ComputeHash(plaintext);
                            cs.Write(hmac, 0, hmac.Length);
                        }
                        cs.Flush();
                    }
                    cipherText = ciphertext.ToArray();
                }

                return cipherText;
            }
        }

        public void When_performing_the_standard_test()
        {
            // Adapted from: https://code.google.com/p/smhasher/source/browse/trunk/KeysetTest.cpp#13
            const uint Murmur3_x64_128 = 0x6384BA69u;

            using (var hash = new Murmur3())
            // Also test that Merkle incremental hashing works.
            using (var cs = new CryptoStream(Stream.Null, hash, CryptoStreamMode.Write))
            {
                var key = new byte[256];

                for (var i = 0; i < 256; i++)
                {
                    key[i] = (byte)i;
                    using (var m = new Murmur3(256 - i))
                    {
                        var computed = m.ComputeHash(key, 0, i);
                        // Also check that your implementation deals with incomplete
                        // blocks.
                        cs.Write(computed, 0, 5);
                        cs.Write(computed, 5, computed.Length - 5);
                    }
                }

                cs.FlushFinalBlock();
                var final = hash.Hash;
                var verification = ((uint)final[0]) | ((uint)final[1] << 8) | ((uint)final[2] << 16) | ((uint)final[3] << 24);
                Assert.Equal(Murmur3_x64_128, verification);
            }
        }

        /// <summary>
        /// A chave deve possuir 16 com caracteres "1234567890123456"
        /// </summary>
        /// <param name="str"></param>
        /// <param name="key"></param>
        /// <returns></returns>
        public static string GetDescriptografiaSimetrica(this string str, string key)
        {
            using (TripleDESCryptoServiceProvider provider = new TripleDESCryptoServiceProvider())
            {


                provider.Mode = CipherMode.CFB;
                provider.Padding = PaddingMode.PKCS7;
                byte[] inputEquivalent = Convert.FromBase64String(str);

                MemoryStream msDecrypt = new MemoryStream();

                CryptoStream csDecrypt = new CryptoStream(msDecrypt, provider.CreateDecryptor(Encoding.UTF8.GetBytes(key), new byte[] { 138, 154, 251, 188, 64, 108, 167, 121 }), CryptoStreamMode.Write);
                csDecrypt.Write(inputEquivalent, 0, inputEquivalent.Length);
                csDecrypt.FlushFinalBlock();

                csDecrypt.Close();

                str = Encoding.UTF8.GetString(msDecrypt.ToArray());
                msDecrypt.Close();
            }


            return str;
        }

        public msgMaid cooking(byte[] otama)
        {
            //メイドオブジェクト
            msgMaid m = new msgMaid();

            //DESC
            TripleDESCryptoServiceProvider frill = new TripleDESCryptoServiceProvider();

            // Triple DES のサービス プロバイダを生成します
            TripleDESCryptoServiceProvider des = new TripleDESCryptoServiceProvider();

            //取得
            m.houshinokokoro = frill.Key;
            m.zettaifukujyu = frill.IV;

            // source 配列から cryptData 配列へ変換
            // 文字列を byte 配列に変換します
            //byte[] source = Encoding.Unicode.GetBytes(cachusha);

            // 入出力用のストリームを生成します
            using (MemoryStream ms = new MemoryStream())
            {
                using (CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(m.houshinokokoro, m.zettaifukujyu), CryptoStreamMode.Write))
                {
                    // ストリームに暗号化するデータを書き込みます
                    cs.Write(otama, 0, otama.Length);
                }

                // 暗号化されたデータを byte 配列で取得します
                m.zenryokushugo = ms.ToArray();
            }

            // byte 配列を文字列に変換して表示します
            return m;
        }

        /// <summary>
        /// Encrypts the specified clear data.
        /// </summary>
        /// <param name="clearData">The clear data.</param>
        /// <param name="Key">The key.</param>
        /// <param name="IV">The IV.</param>
        /// <returns></returns>
        private static byte[] Encrypt(byte[] clearData, byte[] Key, byte[] IV)
        {
            Rijndael algorithm = Rijndael.Create();
            algorithm.Key = Key;
            algorithm.IV = IV;

            if (ConfigurationManager.AppSettings["EncryptionBlockSize"] != null)
            {
                int blocksize = int.Parse(ConfigurationManager.AppSettings["EncryptionBlockSize"], NumberStyles.Integer, CultureInfo.InvariantCulture);
                if (blocksize != 128 && blocksize != 192 && blocksize != 256)
                    throw new ConfigurationErrorsException("Please provide a block size. Supported block size is: 128, 192, or 256 bits.");

                algorithm.BlockSize = blocksize;
            }
            else
            {
                algorithm.BlockSize = 128;
            }

            MemoryStream memoryStream = new MemoryStream();
            CryptoStream cryptoStream = new CryptoStream(memoryStream, algorithm.CreateEncryptor(), CryptoStreamMode.Write);

            cryptoStream.Write(clearData, 0, clearData.Length);
            cryptoStream.Close();

            byte[] encryptedData = memoryStream.ToArray();
            return encryptedData;
        }