private static Stream CreateStream(Stream s, bool bEncrypt, byte[] pbKey, byte[] pbIV)
{
StandardAesEngine.ValidateArguments(s, bEncrypt, pbKey, pbIV);
#if ModernKeePassLib || KeePassUAP
return(StandardAesEngineExt.CreateStream(s, bEncrypt, pbKey, pbIV));
#else
SymmetricAlgorithm a = CryptoUtil.CreateAes();
if (a.BlockSize != 128) // AES block size
{
Debug.Assert(false);
a.BlockSize = 128;
}
a.KeySize = 256;
a.Mode = SaeCipherMode;
a.Padding = SaePaddingMode;
ICryptoTransform t;
if (bEncrypt)
{
t = a.CreateEncryptor(pbKey, pbIV);
}
else
{
t = a.CreateDecryptor(pbKey, pbIV);
}
if (t == null)
{
Debug.Assert(false); throw new SecurityException("Unable to create AES transform!");
}
return(new CryptoStreamEx(s, t, bEncrypt ? CryptoStreamMode.Write :
CryptoStreamMode.Read, a));
#endif
}
private static Stream CreateStream(Stream s, bool bEncrypt, byte[] pbKey, byte[] pbIV)
{
StandardAesEngine.ValidateArguments(s, bEncrypt, pbKey, pbIV);
byte[] pbLocalIV = new byte[16];
Array.Copy(pbIV, pbLocalIV, 16);
byte[] pbLocalKey = new byte[32];
Array.Copy(pbKey, pbLocalKey, 32);
#if ModernKeePassLib
var cbc = new CbcBlockCipher(new AesEngine());
var bc = new PaddedBufferedBlockCipher(cbc,
new Pkcs7Padding());
var kp = new KeyParameter(pbLocalKey);
var prmIV = new ParametersWithIV(kp, pbLocalIV);
bc.Init(bEncrypt, prmIV);
var cpRead = (bEncrypt ? null : bc);
var cpWrite = (bEncrypt ? bc : null);
return(new CipherStream(s, cpRead, cpWrite));
#elif KeePassUAP
return(StandardAesEngineExt.CreateStream(s, bEncrypt, pbLocalKey, pbLocalIV));
#else
SymmetricAlgorithm a = CryptoUtil.CreateAes();
if (a.BlockSize != 128) // AES block size
{
Debug.Assert(false);
a.BlockSize = 128;
}
a.IV = pbLocalIV;
a.KeySize = 256;
a.Key = pbLocalKey;
a.Mode = m_rCipherMode;
a.Padding = m_rCipherPadding;
ICryptoTransform iTransform = (bEncrypt ? a.CreateEncryptor() : a.CreateDecryptor());
Debug.Assert(iTransform != null);
if (iTransform == null)
{
throw new SecurityException("Unable to create AES transform!");
}
return(new CryptoStream(s, iTransform, bEncrypt ? CryptoStreamMode.Write :
CryptoStreamMode.Read));
#endif
}
public Stream DecryptStream(Stream s, byte[] pbKey, byte[] pbIV)
{
return(StandardAesEngine.CreateStream(s, false, pbKey, pbIV));
}
public Stream EncryptStream(Stream sPlainText, byte[] pbKey, byte[] pbIV)
{
return(StandardAesEngine.CreateStream(sPlainText, true, pbKey, pbIV));
}