public virtual byte[] ProcessBlock(
byte[] @in,
int inOff,
int inLen)
{
if (ForEncryption)
{
if (KeyPairGenerator != null)
{
EphemeralKeyPair ephKeyPair = KeyPairGenerator.Generate();
PrivParam = ephKeyPair.GetKeyPair().Private;
V = ephKeyPair.GetEncodedPublicKey();
}
}
else
{
if (KeyParser != null)
{
MemoryStream bIn = new MemoryStream(@in, inOff, inLen)
{
Position = 0
};
try
{
PubParam = KeyParser.ReadKey(bIn);
}
catch (IOException e)
{
throw new InvalidCipherTextException("unable to recover ephemeral public key: " + e.Message, e);
}
catch (ArgumentException e)
{
throw new InvalidCipherTextException("unable to recover ephemeral public key: " + e.Message, e);
}
int encLength = (inLen - (int)(bIn.Length - bIn.Position));
V = Arrays.CopyOfRange(@in, inOff, inOff + encLength);
}
}
// Compute the common value and convert to byte array.
Agree.Init(PrivParam);
BigInteger z = Agree.CalculateAgreement(PubParam);
byte[] bigZ = BigIntegers.AsUnsignedByteArray(Agree.GetFieldSize(), z);
// Create input to KDF.
if (V.Length != 0)
{
byte[] vz = Arrays.Concatenate(V, bigZ);
Arrays.Fill(bigZ, 0);
bigZ = vz;
}
try
{
// Initialise the KDF.
KdfParameters kdfParam = new KdfParameters(bigZ, _param.GetDerivationV());
Kdf.Init(kdfParam);
return(ForEncryption
? EncryptBlock(@in, inOff, inLen)
: DecryptBlock(@in, inOff, inLen));
}
finally
{
Arrays.Fill(bigZ, 0);
}
}
public override byte[] ProcessBlock(
byte[] @in,
int inOff,
int inLen)
{
if (ForEncryption)
{
if (KeyPairGenerator != null)
{
EphemeralKeyPair ephKeyPair = KeyPairGenerator.Generate();
PrivParam = ephKeyPair.GetKeyPair().Private;
V = ephKeyPair.GetEncodedPublicKey();
}
}
else
{
if (KeyParser != null)
{
MemoryStream bIn = new MemoryStream(@in, inOff, inLen)
{
Position = SecureHeadSize
};
try
{
PubParam = KeyParser.ReadKey(bIn);
}
catch (IOException e)
{
throw new InvalidCipherTextException("unable to recover ephemeral public key: " + e.Message, e);
}
catch (ArgumentException e)
{
throw new InvalidCipherTextException("unable to recover ephemeral public key: " + e.Message, e);
}
int encLength = (inLen - (int)(bIn.Length - bIn.Position));
V = Arrays.CopyOfRange(@in, inOff + SecureHeadSize, inOff + encLength);
}
}
// Compute the common value and convert to byte array.
Agree.Init(PrivParam);
BigInteger z = Agree.CalculateAgreement(PubParam);
byte[] bigZ = BigIntegers.AsUnsignedByteArray(Agree.GetFieldSize(), z);
try
{
// Initialise the KDF.
KdfParameters kdfParam = new KdfParameters(bigZ, null);
Kdf.Init(kdfParam);
if (ForEncryption)
{
return(EncryptBlock(@in, inOff, inLen));
}
else
{
byte[] temp = new byte[inLen - SecureHeadSize];
Array.Copy(@in, inOff + SecureHeadSize, temp, 0, temp.Length);
return(DecryptBlock(temp, inOff, temp.Length));
}
}
finally
{
Arrays.Fill(bigZ, 0);
}
}
