public byte[] Encrypt(byte[] srcBuffer)
{
try
{
byte[] buffer = srcBuffer; // srcStream.GetBuffer();
int bufferlen = buffer.Length;
MemoryStream mStream = new MemoryStream();
CryptoStream cStream = new CryptoStream(mStream, encryptor, CryptoStreamMode.Write);
cStream.Write(buffer, 0, bufferlen);
cStream.FlushFinalBlock();
byte[] result = mStream.ToArray();
cStream.Close();
des.Clear();
return(result);
}
catch (System.Exception ex)
{
#if DEBUG
throw ex;
#else
log.Error(ex.ToString());
return(null);
#endif
}
}
public byte[] Encrypt(byte[] srcBuffer)
{
try
{
byte[] buffer = srcBuffer;// srcStream.GetBuffer();
int bufferlen = buffer.Length;
lock (this)
{
byte[] result = encryptor.TransformFinalBlock(srcBuffer, 0, bufferlen);
aes.Clear();
return(result);
}
}
catch (System.Exception ex)
{
#if DEBUG
throw ex;
#else
log.Error(ex.ToString());
return(null);
#endif
}
}
private byte[] TransformByCryptoStream(SymmetricAlgorithm algorithm, byte[] bytes, bool encrypt)
{
algorithm.Clear();
if (encrypt)
return TransformByCryptoStream(algorithm.CreateEncryptor(), bytes);
else
return TransformByCryptoStream(algorithm.CreateDecryptor(), bytes);
}
// All symmetric algorithms inherit from the SymmetricAlgorithm base class, to which we can cast from the original crypto service provider
private byte[] SymmetricEncrypt(SymmetricAlgorithm Provider, byte[] plainText, string key, int keySize)
{
byte[] ivBytes = null;
switch (keySize / 8)
{
//Determine which initialization vector to use
case 8:
ivBytes = IV_8;
break;
case 16:
ivBytes = IV_16;
break;
case 24:
ivBytes = IV_24;
break;
case 32:
ivBytes = IV_32;
break;
default:
break;
//TODO: Throw an error because an invalid key length has been passed
}
Provider.KeySize = keySize;
//Generate a secure key based on the original password by using SALT
byte[] keyStream = DerivePassword(key, keySize / 8);
//Initialize our encryptor object
ICryptoTransform trans = Provider.CreateEncryptor(keyStream, ivBytes);
//Perform the encryption on the textStream byte array
byte[] result = trans.TransformFinalBlock(plainText, 0, plainText.GetLength(0));
//Release cryptographic resources
Provider.Clear();
trans.Dispose();
return result;
}
//All symmetric algorithms inherit from the SymmetricAlgorithm base class, to which we can cast from the original crypto service provider
public byte[] SymmetricDecrypt(SymmetricAlgorithm Provider, byte[] encByte, string key, int keySize)
{
byte[] ivBytes = null;
switch (keySize / 8)
{
//Determine which initialization vector to use
case 8:
ivBytes = IV_8;
break;
case 16:
ivBytes = IV_16;
break;
case 24:
ivBytes = IV_24;
break;
case 32:
ivBytes = IV_32;
break;
default:
break;
//TODO: Throw an error because an invalid key length has been passed
}
//Generate a secure key based on the original password by using SALT
byte[] keyStream = DerivePassword(key, keySize / 8);
//Convert our hex-encoded cipher text to a byte array
byte[] textStream = encByte;
//HexToBytes(encText)
Provider.KeySize = keySize;
//Initialize our decryptor object
ICryptoTransform trans = Provider.CreateDecryptor(keyStream, ivBytes);
//Initialize the result stream
byte[] result = null;
try
{
result = trans.TransformFinalBlock(textStream, 0, textStream.GetLength(0));
}
catch (Exception ex)
{
throw new System.Security.Cryptography.CryptographicException("The following exception occurred during decryption: " + ex.Message);
}
finally
{
Provider.Clear();
trans.Dispose();
}
return result;
}
protected static byte[] Encrypt(byte[] plainText, SymmetricAlgorithm encryptionAlgorithm, string base64Key, string base64IV)
{
if (base64Key == null || base64Key.Length == 0)
{
throw new Exception("Empty Key");
}
if (base64IV == null || base64IV.Length == 0)
{
throw new Exception("Empty Initialization Vector");
}
encryptionAlgorithm.Key = Convert.FromBase64String(base64Key);
encryptionAlgorithm.IV = Convert.FromBase64String(base64IV);
byte[] cipherValue = null;
byte[] plainValue = plainText;
MemoryStream memStream = new MemoryStream();
CryptoStream cryptoStream = new CryptoStream(memStream, encryptionAlgorithm.CreateEncryptor(), CryptoStreamMode.Write);
try
{
// Write the encrypted information
cryptoStream.Write(plainValue, 0, plainValue.Length);
cryptoStream.Flush();
cryptoStream.FlushFinalBlock();
// Get the encrypted stream
cipherValue = memStream.ToArray();
}
finally
{
// Clear the arrays
if (plainValue != null)
{
Array.Clear(plainValue, 0, plainValue.Length);
}
memStream.Close();
cryptoStream.Close();
encryptionAlgorithm.Clear();
((IDisposable)encryptionAlgorithm).Dispose();
}
return cipherValue;
}
protected static byte[] Decrypt(byte[] cipherText, SymmetricAlgorithm encryptionAlgorithm, string base64Key, string base64IV)
{
if (base64Key == null || base64Key.Length == 0)
{
throw new Exception("Empty Key");
}
if (base64IV == null || base64IV.Length == 0)
{
throw new Exception("Empty Initialization Vector");
}
encryptionAlgorithm.Key = Convert.FromBase64String(base64Key);
encryptionAlgorithm.IV = Convert.FromBase64String(base64IV);
byte[] cipherValue = cipherText;
byte[] plainValue = new byte[cipherValue.Length + 1];
MemoryStream memStream = new MemoryStream(cipherValue);
CryptoStream cryptoStream = new CryptoStream(memStream, encryptionAlgorithm.CreateDecryptor(), CryptoStreamMode.Read);
try
{
// Decrypt the data
cryptoStream.Read(plainValue, 0, plainValue.Length);
}
finally
{
// Clear the arrays
if (cipherValue != null)
{
Array.Clear(cipherValue, 0, cipherValue.Length);
}
memStream.Close();
//Flush the stream buffer
cryptoStream.Close();
encryptionAlgorithm.Clear();
((IDisposable)encryptionAlgorithm).Dispose();
}
return plainValue;
}
/// <summary>
/// Creates a random IV value appropriate for
/// the encryption algorithm
/// </summary>
/// <param name="encryptionAlgorithm">Instance of SymmetricAlgorithm used to create the IV</param>
/// <returns>Base64 encoded byte array containing the IV value</returns>
protected static string CreateBase64IV(SymmetricAlgorithm encryptionAlgorithm)
{
byte[] iv = null;
try
{
encryptionAlgorithm.GenerateIV();
iv = encryptionAlgorithm.IV;
}
finally
{
encryptionAlgorithm.Clear();
((IDisposable)encryptionAlgorithm).Dispose();
}
return Convert.ToBase64String(iv);
}
/// <summary>
/// Creates a random key value appropriate for
/// the encryption algorithm
/// </summary>
/// <param name="encryptionAlgorithm">Instance of SymmetricAlgorithm used to create the key</param>
/// <returns>Base64 encoded byte array containing the key value</returns>
public static string CreateBase64Key(SymmetricAlgorithm encryptionAlgorithm)
{
byte[] key = null;
try
{
encryptionAlgorithm.GenerateKey();
key = encryptionAlgorithm.Key;
}
finally
{
encryptionAlgorithm.Clear();
((IDisposable)encryptionAlgorithm).Dispose();
}
return Convert.ToBase64String(key);
}
/// <summary>
///Decrypt an array of bytes using key and insertion vector (also called block size). NOTE: This is the base
/// method for decryption methods. Other decryption methods are convenience overloads
/// </summary>
/// <param name="encryptedBytes">Non-null,non-zero length array of bytes to decrypt</param>
/// <param name="keyBytes">Key for encryption algorithm. Must be 126, 128, or 256 bits (16, 24, 32 bytes) </param>
/// <param name="ivBytes">Insertion vector (also called block size). Must be 126, 128, or 256 bits (16, 24, 32 bytes)</param>
/// <param name="encryptor">.Net library that will perform actual decryption</param>
/// <returns>An encrypted byte array</returns>
private byte[] decode(SymmetricAlgorithm encryptor, byte[] encryptedBytes, byte[] keyBytes, byte[] ivBytes)
{
// Create a MemoryStream that is going to accept the
// decrypted bytes
using (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();
try
{
// explicitly set block sizes since
// keys may not be default lengths
// Legal values are:
// Key Size: 128, 192, 256
// Block Size: 128, 192, 256
// Bytes 16, 24, 32
encryptor.BlockSize = ivBytes.Length * 8;
encryptor.KeySize = keyBytes.Length * 8;
// 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.
encryptor.Key = keyBytes;
encryptor.IV = ivBytes;
// 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.
using (CryptoStream cs = new CryptoStream(ms,
encryptor.CreateDecryptor(), CryptoStreamMode.Write))
{
// Write the data and make it do the decryption
cs.Write(encryptedBytes, 0, encryptedBytes.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;
}
}
finally
{
if (encryptor != null)
{
encryptor.Clear(); //remove any resources this might have
}
}
} //using memory stream
}
/// <summary> Symmetrical function to Decrypt
/// </summary>
/// <param name="provider">Type of provider</param>
/// <param name="encText">To be decrypted content</param>
/// <param name="key">Type key</param>
/// <param name="keySize">Size of key</param>
/// <returns></returns>
private byte[] SymmetricDecrypt(SymmetricAlgorithm provider, string encText, string key, int keySize)
{
//All symmetric algorithms inherit from the SymmetricAlgorithm base class, to which we can cast from the original crypto service provider
byte[] ivBytes = GetInitializationVector(keySize);
//Generate a secure key based on the original password by using SALT
byte[] keyStream = DerivePassword(key, keySize / 8);
//Convert our hex-encoded cipher text to a byte array
byte[] textStream = HexToBytes(encText);
provider.KeySize = keySize;
//Initialize our decryptor object
ICryptoTransform trans = provider.CreateDecryptor(keyStream, ivBytes);
//Initialize the result stream
byte[] result = null;
try
{
//Perform the decryption on the textStream byte array
result = trans.TransformFinalBlock(textStream, 0, textStream.Length);
}
catch (Exception ex)
{
throw new System.Security.Cryptography.CryptographicException("The following exception occurred during decryption: " + ex.Message);
}
finally
{
//Release cryptographic resources
provider.Clear();
trans.Dispose();
}
return result;
}
/// <summary> Symmetrical function to Encrypt
/// </summary>
/// <param name="provider">Type of provider</param>
/// <param name="encText">To be encrypted content</param>
/// <param name="key">Type key</param>
/// <param name="keySize">Size of key</param>
/// <returns>Array of byte</returns>
private byte[] SymmetricEncrypt(SymmetricAlgorithm provider, byte[] plainText, string key, int keySize)
{
//All symmetric algorithms inherit from the SymmetricAlgorithm base class, to which we can cast from the original crypto service provider
byte[] ivBytes = GetInitializationVector(keySize);
provider.KeySize = keySize;
//Generate a secure key based on the original password by using SALT
byte[] keyStream = DerivePassword(key, keySize / 8);
//Initialize our encryptor object
ICryptoTransform trans = provider.CreateEncryptor(keyStream, ivBytes);
//Perform the encryption on the textStream byte array
byte[] result = trans.TransformFinalBlock(plainText, 0, plainText.GetLength(0));
//Release cryptographic resources
provider.Clear();
trans.Dispose();
return result;
}
/// <summary>
///
/// </summary>
/// <param name="Doc"></param>
/// <param name="ElementName">Ruta completa del elemento a encriptar
/// Ejemplos:
/// <example>
/// Encripta el precio los libros cuyo precio es mayor a 35
/// /bookstore/book[price>35]/price
///
/// Busca el grupos "ValidationExceptionMessage" y dentro de este la clave con nombre "MaxLenghtField"
/// "/ConfigurationFile/Groups/Group[@name='ValidationExceptionMessage']/Keys/Key[@name='MaxLenghtField']"
///
///
/// "//EXAMPLE/CUSTOMER[substring(@type,1,2) ='DE']"
/// "//EXAMPLE/CUSTOMER[contains(@type,'DECEA')]"
/// </example>
/// </param>
/// <param name="Key"></param>
public static string Encrypt(string xml, string elementPath, SymmetricAlgorithm symmetricAlgorithm)
{
// Check the arguments.
if (string.IsNullOrEmpty(xml))
throw new ArgumentNullException("xml");
if (string.IsNullOrEmpty(elementPath))
throw new ArgumentNullException("elementPath");
if (symmetricAlgorithm == null)
throw new ArgumentNullException("SymmetricAlgorithm");
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.PreserveWhitespace = true;
xmlDoc.LoadXml(xml);
///bookstore/book[price>35]/price
/// "/ConfigurationFile/Groups/Group[@name='ValidationExceptionMessage']/Keys/Key[@name='MaxLenghtField']"
XmlElement elementToEncrypt = xmlDoc.SelectSingleNode(elementPath) as XmlElement;
// Throw an XmlException if the element was not found.
if (elementToEncrypt == null)
{
throw new XmlException("The specified element was not found");
}
//////////////////////////////////////////////////
// Creo una instancia de EncryptedXml y la uso
// para encriptar XmlElement con lka clave simetrica
//////////////////////////////////////////////////
EncryptedXml eXml = new EncryptedXml();
byte[] encryptedElement = eXml.EncryptData(elementToEncrypt, symmetricAlgorithm, false);
// Construct an EncryptedData object and populate
// it with the desired encryption information.
EncryptedData edElement = new EncryptedData();
edElement.Type = EncryptedXml.XmlEncElementUrl;
edElement.EncryptionMethod = GetEncrypTionMethod(symmetricAlgorithm);
//// Add the encrypted element data to the EncryptedData object.
edElement.CipherData.CipherValue = encryptedElement;
// Create a new KeyInfo element.
edElement.KeyInfo = new KeyInfo();
//// Encrypt the session key and add it to an EncryptedKey element.
//EncryptedKey ek = new EncryptedKey();
//// Create a new KeyInfoName element.
//KeyInfoName kin = new KeyInfoName();
//// Specify a name for the key.
//kin.Value = KeyName;
//// Add the KeyInfoName element to the
//// EncryptedKey object.
//ek.KeyInfo.AddClause(kin);
// Add the encrypted key to the
// EncryptedData object.
//edElement.KeyInfo.AddClause(new KeyInfoEncryptedKey(ek));
// Replace the element from the original XmlDocument object with the EncryptedData element.
EncryptedXml.ReplaceElement(elementToEncrypt, edElement, false);
symmetricAlgorithm.Clear();
xml = xmlDoc.InnerXml;
xmlDoc = null;
return xml;
}
public static string Decrypt(string xmlEncrypted, string elementPath, SymmetricAlgorithm symmetricAlgorithm)
{
// Check the arguments.
if (string.IsNullOrEmpty(xmlEncrypted))
throw new ArgumentNullException("xml");
if (string.IsNullOrEmpty(elementPath))
throw new ArgumentNullException("elementPath");
if (symmetricAlgorithm == null)
throw new ArgumentNullException("SymmetricAlgorithm ");
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.PreserveWhitespace = true;
xmlDoc.LoadXml(xmlEncrypted);
// Find the EncryptedData element in the XmlDocument.
XmlNodeList encryptedElementxmlDoc = xmlDoc.GetElementsByTagName("EncryptedData");
// If the EncryptedData element was not found, throw an exception.
if (encryptedElementxmlDoc == null)
{
throw new XmlException("The EncryptedData element was not found.");
}
EncryptedData edElement;
EncryptedXml exml = new EncryptedXml(xmlDoc);
// Add a key-name mapping.
// This method can only decrypt documents
// that present the specified key name.
exml.AddKeyNameMapping("", symmetricAlgorithm);
exml.DecryptDocument();
//foreach (XmlNode node in encryptedElementxmlDoc)
//{
// // Create an EncryptedData object and populate it.
// edElement = new EncryptedData();
// edElement.LoadXml(node as XmlElement);
// exml = new EncryptedXml();
// exml.DecryptDocument();
// //// Decrypt the element using the symmetric key.
// //byte[] rgbOutput = exml.DecryptData(edElement, symmetricAlgorithm);
// //// Replace the encryptedData element with the plaintext XML element.
// //exml.ReplaceData(node as XmlElement, rgbOutput);
//}
symmetricAlgorithm.Clear();
xmlEncrypted = xmlDoc.InnerXml;
xmlDoc = null;
return xmlEncrypted;
}
