public static byte[] DecryptData(string password, AutoSaltSizes saltSize, byte[] data, SymmetricCryptoAlgorithm algorithm = SymmetricCryptoAlgorithm.AES_256_CBC)
{
DecryptionBuffer decBuffer = new DecryptionBuffer(password, saltSize, algorithm);
decBuffer.AddData(data, true);
return(decBuffer.GetData());
}
public static void DecryptStream(string password, AutoSaltSizes saltSize, Stream inputStream, Stream outputStream, SymmetricCryptoAlgorithm algorithm = SymmetricCryptoAlgorithm.AES_256_CBC)
{
if (!inputStream.CanRead)
{
throw new Exception("The input stream has to support read");
}
if (!outputStream.CanWrite)
{
throw new Exception("The output stream has to support write");
}
DecryptionBuffer decBuffer = new DecryptionBuffer(password, saltSize, algorithm);
byte[] readBuffer = new byte[500000];
bool isLastData = false;
while (!isLastData)
{
int nrOfBytes = inputStream.Read(readBuffer, 0, readBuffer.Length);
isLastData = (nrOfBytes == 0);
decBuffer.AddData(readBuffer, 0, nrOfBytes, isLastData);
byte[] decryptedData = decBuffer.GetData();
outputStream.Write(decryptedData, 0, decryptedData.Length);
}
}
public DecryptionBuffer(byte[] keyBytes, AutoSaltSizes saltSize, SymmetricCryptoAlgorithm cryptoAlgorithm = SymmetricCryptoAlgorithm.AES_256_CBC, PaddingMode paddingMode = PaddingMode.PKCS7)
{
_autoSaltLength = (int)saltSize;
_autoSaltCryptoAlgorithm = cryptoAlgorithm;
_keyBytes = keyBytes;
_autosizeSalt = true;
_autoSaltPaddingMode = paddingMode;
}
public static void DecryptFile(string password, AutoSaltSizes saltSize, string inputFileName, string outputFileName, SymmetricCryptoAlgorithm algorithm = SymmetricCryptoAlgorithm.AES_256_CBC)
{
using (FileStream inputStream = new FileStream(inputFileName, FileMode.Open, FileAccess.Read))
{
using (FileStream outputStream = new FileStream(outputFileName, FileMode.Create, FileAccess.Write))
{
DecryptStream(password, saltSize, inputStream, outputStream, algorithm);
}
}
}
public EncryptionBuffer(byte[] keyBytes, AutoSaltSizes saltSize, SymmetricCryptoAlgorithm cryptoAlgorithm = SymmetricCryptoAlgorithm.AES_256_CBC, PaddingMode paddingMode = PaddingMode.PKCS7)
{
byte[] salt = new byte[(int)saltSize];
using (RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider())
rng.GetBytes(salt);
_outBuffer.AddBytes(salt);
if (saltSize == AutoSaltSizes.Salt32)
{
// Since the smallest supported salt in Rfc2898DeriveBytes is 8 bytes we write the 4 byte salt twice
ByteBuffer newSalt = new ByteBuffer();
newSalt.AddBytes(salt);
newSalt.AddBytes(salt);
salt = newSalt.GetAllBytes();
}
Rfc2898DeriveBytes key = new Rfc2898DeriveBytes(keyBytes, salt, 7);
Initialize(key, cryptoAlgorithm, paddingMode);
}
public static string DecryptBase64String(string password, AutoSaltSizes saltSize, string b64StrData, SymmetricCryptoAlgorithm algorithm = SymmetricCryptoAlgorithm.AES_256_CBC)
{
byte[] data = Convert.FromBase64String(b64StrData);
byte[] encryptedData = DecryptData(password, saltSize, data, algorithm);
return(CryptoCommon.GetString(encryptedData));
}
public static string EncryptString(string password, AutoSaltSizes saltSize, string strData, SymmetricCryptoAlgorithm algorithm = SymmetricCryptoAlgorithm.AES_256_CBC)
{
byte[] data = CryptoCommon.GetBytes(strData);
byte[] encryptedData = EncryptData(password, saltSize, data, algorithm);
return(CryptoCommon.GetString(encryptedData));
}
