private byte[] GenerateKdfBytes(
KdfParameters kParam,
int length)
{
byte[] buf = new byte[length];
kdf.Init(kParam);
kdf.GenerateBytes(buf, 0, buf.Length);
return buf;
}
private byte[] DecryptBlock(
byte[] in_enc,
int inOff,
int inLen,
byte[] z)
{
byte[] M = null;
KeyParameter macKey = null;
KdfParameters kParam = new KdfParameters(z, param.GetDerivationV());
int macKeySize = param.MacKeySize;
kdf.Init(kParam);
// Ensure that the length of the input is greater than the MAC in bytes
if (inLen < mac.GetMacSize())
throw new InvalidCipherTextException("Length of input must be greater than the MAC");
inLen -= mac.GetMacSize();
if (cipher == null) // stream mode
{
byte[] Buffer = GenerateKdfBytes(kParam, inLen + (macKeySize / 8));
M = new byte[inLen];
for (int i = 0; i != inLen; i++)
{
M[i] = (byte)(in_enc[inOff + i] ^ Buffer[i]);
}
macKey = new KeyParameter(Buffer, inLen, (macKeySize / 8));
}
else
{
int cipherKeySize = ((IesWithCipherParameters)param).CipherKeySize;
byte[] Buffer = GenerateKdfBytes(kParam, (cipherKeySize / 8) + (macKeySize / 8));
cipher.Init(false, new KeyParameter(Buffer, 0, (cipherKeySize / 8)));
M = cipher.DoFinal(in_enc, inOff, inLen);
macKey = new KeyParameter(Buffer, (cipherKeySize / 8), (macKeySize / 8));
}
byte[] macIV = param.GetEncodingV();
mac.Init(macKey);
mac.BlockUpdate(in_enc, inOff, inLen);
mac.BlockUpdate(macIV, 0, macIV.Length);
mac.DoFinal(macBuf, 0);
inOff += inLen;
byte[] T1 = Arrays.CopyOfRange(in_enc, inOff, inOff + macBuf.Length);
if (!Arrays.ConstantTimeAreEqual(T1, macBuf))
throw (new InvalidCipherTextException("Invalid MAC."));
return M;
}
private byte[] EncryptBlock(
byte[] input,
int inOff,
int inLen,
byte[] z)
{
byte[] C = null;
KeyParameter macKey = null;
KdfParameters kParam = new KdfParameters(z, param.GetDerivationV());
int c_text_length = 0;
int macKeySize = param.MacKeySize;
if (cipher == null) // stream mode
{
byte[] Buffer = GenerateKdfBytes(kParam, inLen + (macKeySize / 8));
C = new byte[inLen + mac.GetMacSize()];
c_text_length = inLen;
for (int i = 0; i != inLen; i++)
{
C[i] = (byte)(input[inOff + i] ^ Buffer[i]);
}
macKey = new KeyParameter(Buffer, inLen, (macKeySize / 8));
}
else
{
int cipherKeySize = ((IesWithCipherParameters)param).CipherKeySize;
byte[] Buffer = GenerateKdfBytes(kParam, (cipherKeySize / 8) + (macKeySize / 8));
cipher.Init(true, new KeyParameter(Buffer, 0, (cipherKeySize / 8)));
c_text_length = cipher.GetOutputSize(inLen);
byte[] tmp = new byte[c_text_length];
int len = cipher.ProcessBytes(input, inOff, inLen, tmp, 0);
len += cipher.DoFinal(tmp, len);
C = new byte[len + mac.GetMacSize()];
c_text_length = len;
Array.Copy(tmp, 0, C, 0, len);
macKey = new KeyParameter(Buffer, (cipherKeySize / 8), (macKeySize / 8));
}
byte[] macIV = param.GetEncodingV();
mac.Init(macKey);
mac.BlockUpdate(C, 0, c_text_length);
mac.BlockUpdate(macIV, 0, macIV.Length);
//
// return the message and it's MAC
//
mac.DoFinal(C, c_text_length);
return C;
}
private byte[] DecryptBlock(
byte[] in_enc,
int inOff,
int inLen,
byte[] z)
{
byte[] M = null;
KeyParameter macKey = null;
KdfParameters kParam = new KdfParameters(z, param.GetDerivationV());
int macKeySize = param.MacKeySize;
kdf.Init(kParam);
inLen -= mac.GetMacSize();
if (cipher == null) // stream mode
{
byte[] Buffer = GenerateKdfBytes(kParam, inLen + (macKeySize / 8));
M = new byte[inLen];
for (int i = 0; i != inLen; i++)
{
M[i] = (byte)(in_enc[inOff + i] ^ Buffer[i]);
}
macKey = new KeyParameter(Buffer, inLen, (macKeySize / 8));
}
else
{
int cipherKeySize = ((IesWithCipherParameters)param).CipherKeySize;
byte[] Buffer = GenerateKdfBytes(kParam, (cipherKeySize / 8) + (macKeySize / 8));
cipher.Init(false, new KeyParameter(Buffer, 0, (cipherKeySize / 8)));
M = cipher.DoFinal(in_enc, inOff, inLen);
macKey = new KeyParameter(Buffer, (cipherKeySize / 8), (macKeySize / 8));
}
byte[] macIV = param.GetEncodingV();
mac.Init(macKey);
mac.BlockUpdate(in_enc, inOff, inLen);
mac.BlockUpdate(macIV, 0, macIV.Length);
mac.DoFinal(macBuf, 0);
inOff += inLen;
for (int t = 0; t < macBuf.Length; t++)
{
if (macBuf[t] != in_enc[inOff + t])
{
throw (new InvalidCipherTextException("IMac codes failed to equal."));
}
}
return M;
}
private byte[] EncryptBlock(byte[] input, int inOff, int inLen, byte[] z)
{
byte[] c;
KeyParameter macKey;
var kParam = new KdfParameters(z, _param.Derivation);
int cTextLength;
var macKeySize = _param.MacKeySize;
if (_cipher == null) // stream mode
{
var buffer = GenerateKdfBytes(kParam, inLen + (macKeySize / 8));
c = new byte[inLen + _mac.GetMacSize()];
cTextLength = inLen;
for (var i = 0; i != inLen; i++)
{
c[i] = (byte)(input[inOff + i] ^ buffer[i]);
}
macKey = new KeyParameter(buffer, inLen, (macKeySize / 8));
}
else
{
var cipherKeySize = ((IesWithCipherParameters)_param).CipherKeySize;
var buffer = GenerateKdfBytes(kParam, (cipherKeySize / 8) + (macKeySize / 8));
_cipher.Init(true, new KeyParameter(buffer, 0, (cipherKeySize / 8)));
cTextLength = _cipher.GetOutputSize(inLen);
var tmp = new byte[cTextLength];
var len = _cipher.ProcessBytes(input, inOff, inLen, tmp, 0);
len += _cipher.DoFinal(tmp, len);
c = new byte[len + _mac.GetMacSize()];
cTextLength = len;
Array.Copy(tmp, 0, c, 0, len);
macKey = new KeyParameter(buffer, (cipherKeySize / 8), (macKeySize / 8));
}
var macIV = _param.Encoding;
_mac.Init(macKey);
_mac.BlockUpdate(c, 0, cTextLength);
_mac.BlockUpdate(macIV, 0, macIV.Length);
//
// return the message and it's MAC
//
_mac.DoFinal(c, cTextLength);
return c;
}
private byte[] DecryptBlock(byte[] inEnc, int inOff, int inLen, byte[] z)
{
byte[] m;
KeyParameter macKey;
var kParam = new KdfParameters(z, _param.Derivation);
var macKeySize = _param.MacKeySize;
_kdf.Init(kParam);
inLen -= _mac.GetMacSize();
if (_cipher == null) // stream mode
{
var buffer = GenerateKdfBytes(kParam, inLen + (macKeySize / 8));
m = new byte[inLen];
for (var i = 0; i != inLen; i++)
{
m[i] = (byte)(inEnc[inOff + i] ^ buffer[i]);
}
macKey = new KeyParameter(buffer, inLen, (macKeySize / 8));
}
else
{
var cipherKeySize = ((IesWithCipherParameters)_param).CipherKeySize;
var buffer = GenerateKdfBytes(kParam, (cipherKeySize / 8) + (macKeySize / 8));
_cipher.Init(false, new KeyParameter(buffer, 0, (cipherKeySize / 8)));
m = _cipher.DoFinal(inEnc, inOff, inLen);
macKey = new KeyParameter(buffer, (cipherKeySize / 8), (macKeySize / 8));
}
var macIV = _param.Encoding;
_mac.Init(macKey);
_mac.BlockUpdate(inEnc, inOff, inLen);
_mac.BlockUpdate(macIV, 0, macIV.Length);
_mac.DoFinal(_macBuf, 0);
inOff += inLen;
for (var t = 0; t < _macBuf.Length; t++)
{
if (_macBuf[t] != inEnc[inOff + t])
{
throw (new InvalidCipherTextException("IMac codes failed to equal."));
}
}
return m;
}
private void GenerateKey()
{
var sb = new StringBuilder();
sb.Append("Error generating Key").Append(Environment.NewLine);
if(Model.Password.IsNullOrEmpty())
{
sb.Append("Enter Password!").Append(Environment.NewLine);
}
if(Model.Salt.IsNullOrEmpty())
{
sb.Append("Enter Salt!").Append(Environment.NewLine);
}
if (Model.KeySize <= 0)
{
sb.Append("Enter KeySize!").Append(Environment.NewLine);
}
if (!Model.BouncyImplementation && Model.Iterations <= 0)
{
sb.Append("Enter Iterations value!").Append(Environment.NewLine);
}
if (Model.BouncyImplementation && Model.Digest == null)
{
sb.Append("Select Digest!").Append(Environment.NewLine);
}
if (Model.BouncyImplementation && Model.DerivationFunction == null)
{
sb.Append("Select derivation function!").Append(Environment.NewLine);
}
var errors = sb.ToString();
if (!errors.IsNullOrEmpty())
{
MessageBoxContent = new MessageBoxViewModel(CloseMessageBox,
MessageBoxModel.Error(errors));
IsMessageBoxVisible = true;
return;
}
byte[] password = Encoding.UTF32.GetBytes(Model.Password);
byte[] salt = Encoding.UTF32.GetBytes(Model.Salt);
if (Model.BouncyImplementation)
{
Model.Key = new byte[Model.KeySize];
var digest = Model.Digest.Instance<IDigest>();
var kdf = Model.DerivationFunction.Instance<BaseKdfBytesGenerator>(digest);
var kdfParams = new KdfParameters(password, salt);
kdf.Init(kdfParams);
kdf.GenerateBytes(Model.Key, 0, Model.Key.Length);
}
else
{
var k1 = new Rfc2898DeriveBytes(password, salt, Model.Iterations);
Model.Key = k1.GetBytes(Model.KeySize);
}
}
