/*
 Copyright (c) 2008 TrueCrypt Developers Association. All rights reserved.

 Governed by the TrueCrypt License 3.0 the full text of which is contained in
 the file License.txt included in TrueCrypt binary and source code distribution
 packages.
*/

#include "EncryptionAlgorithm.h"
#include "EncryptionModeXTS.h"

namespace VeraCrypt
{
	EncryptionAlgorithm::EncryptionAlgorithm () : Deprecated (false)
	{
	}

	EncryptionAlgorithm::~EncryptionAlgorithm ()
	{
	}

	void EncryptionAlgorithm::Decrypt (byte *data, uint64 length) const
	{
		if_debug (ValidateState ());
		Mode->Decrypt (data, length);
	}

	void EncryptionAlgorithm::Decrypt (const BufferPtr &data) const
	{
		Decrypt (data, data.Size());
	}

	void EncryptionAlgorithm::DecryptSectors (byte *data, uint64 sectorIndex, uint64 sectorCount, size_t sectorSize) const
	{
		if_debug (ValidateState());
		Mode->DecryptSectors (data, sectorIndex, sectorCount, sectorSize);
	}

	void EncryptionAlgorithm::Encrypt (byte *data, uint64 length) const
	{
		if_debug (ValidateState());
		Mode->Encrypt (data, length);
	}

	void EncryptionAlgorithm::Encrypt (const BufferPtr &data) const
	{
		Encrypt (data, data.Size());
	}

	void EncryptionAlgorithm::EncryptSectors (byte *data, uint64 sectorIndex, uint64 sectorCount, size_t sectorSize) const
	{
		if_debug (ValidateState ());
		Mode->EncryptSectors (data, sectorIndex, sectorCount, sectorSize);
	}

	EncryptionAlgorithmList EncryptionAlgorithm::GetAvailableAlgorithms ()
	{
		EncryptionAlgorithmList l;
		
		l.push_back (shared_ptr <EncryptionAlgorithm> (new AES ()));
		l.push_back (shared_ptr <EncryptionAlgorithm> (new Serpent ()));
		l.push_back (shared_ptr <EncryptionAlgorithm> (new Twofish ()));
		l.push_back (shared_ptr <EncryptionAlgorithm> (new AESTwofish ()));
		l.push_back (shared_ptr <EncryptionAlgorithm> (new AESTwofishSerpent ()));
		l.push_back (shared_ptr <EncryptionAlgorithm> (new SerpentAES ()));
		l.push_back (shared_ptr <EncryptionAlgorithm> (new SerpentTwofishAES ()));
		l.push_back (shared_ptr <EncryptionAlgorithm> (new TwofishSerpent ()));

		return l;
	}

	size_t EncryptionAlgorithm::GetLargestKeySize (const EncryptionAlgorithmList &algorithms)
	{
		size_t largestKeySize = 0;

		foreach_ref (const EncryptionAlgorithm &ea, algorithms)
		{
			if (ea.GetKeySize() > largestKeySize)
				largestKeySize = ea.GetKeySize();
		}

		return largestKeySize;
	}

	size_t EncryptionAlgorithm::GetKeySize () const
	{
		if (Ciphers.size() < 1)
			throw NotInitialized (SRC_POS);

		size_t keySize = 0;

		foreach_ref (const Cipher &c, Ciphers)
			keySize += c.GetKeySize();

		return keySize;
	}
	
	size_t EncryptionAlgorithm::GetMaxBlockSize () const
	{
		size_t blockSize = 0;

		foreach_ref (const Cipher &c, Ciphers)
			if (c.GetBlockSize() > blockSize)
				blockSize = c.GetBlockSize();

		return blockSize;
	}

	size_t EncryptionAlgorithm::GetMinBlockSize () const
	{
		size_t blockSize = 0;

		foreach_ref (const Cipher &c, Ciphers)
			if (blockSize == 0 || c.GetBlockSize() < blockSize)
				blockSize = c.GetBlockSize();

		return blockSize;
	}

	shared_ptr <EncryptionMode> EncryptionAlgorithm::GetMode () const
	{
		if (Mode.get() == nullptr)
			throw NotInitialized (SRC_POS);

		return Mode;
	}

	wstring EncryptionAlgorithm::GetName () const
	{
		if (Ciphers.size() < 1)
			throw NotInitialized (SRC_POS);

		wstring name;

		foreach_reverse_ref (const Cipher &c, Ciphers)
		{
			if (name.empty())
				name = c.GetName();
			else
				name += wstring (L"-") + c.GetName();
		}

		return name;
	}

	bool EncryptionAlgorithm::IsModeSupported (const EncryptionMode &mode) const
	{
		bool supported = false;

		foreach_ref (const EncryptionMode &em, SupportedModes)
		{
			if (typeid (mode) == typeid (em))
			{
				supported = true;
				break;
			}
		}

		return supported;
	}

	
	bool EncryptionAlgorithm::IsModeSupported (const shared_ptr <EncryptionMode> mode) const
	{
		return IsModeSupported (*mode);
	}

	void EncryptionAlgorithm::SetMode (shared_ptr <EncryptionMode> mode)
	{
		if (!IsModeSupported (*mode))
			throw ParameterIncorrect (SRC_POS);

		mode->SetCiphers (Ciphers);
		Mode = mode;
	}
	
	void EncryptionAlgorithm::SetKey (const ConstBufferPtr &key)
	{
		if (Ciphers.size() < 1)
			throw NotInitialized (SRC_POS);

		if (GetKeySize() != key.Size())
			throw ParameterIncorrect (SRC_POS);

		size_t keyOffset = 0;
		foreach_ref (Cipher &c, Ciphers)
		{
			c.SetKey (key.GetRange (keyOffset, c.GetKeySize()));
			keyOffset += c.GetKeySize();
		}
	}

	void EncryptionAlgorithm::ValidateState () const
	{
		if (Ciphers.size() < 1 || Mode.get() == nullptr)
			throw NotInitialized (SRC_POS);
	}

	// AES
	AES::AES ()
	{
		Ciphers.push_back (shared_ptr <Cipher> (new CipherAES()));

		SupportedModes.push_back (shared_ptr <EncryptionMode> (new EncryptionModeXTS ()));
	}

	// AES-Twofish
	AESTwofish::AESTwofish ()
	{
		Ciphers.push_back (shared_ptr <Cipher> (new CipherTwofish ()));
		Ciphers.push_back (shared_ptr <Cipher> (new CipherAES ()));

		SupportedModes.push_back (shared_ptr <EncryptionMode> (new EncryptionModeXTS ()));
	}

	// AES-Twofish-Serpent
	AESTwofishSerpent::AESTwofishSerpent ()
	{
		Ciphers.push_back (shared_ptr <Cipher> (new CipherSerpent ()));
		Ciphers.push_back (shared_ptr <Cipher> (new CipherTwofish ()));
		Ciphers.push_back (shared_ptr <Cipher> (new CipherAES ()));

		SupportedModes.push_back (shared_ptr <EncryptionMode> (new EncryptionModeXTS ()));
	}

	// Serpent
	Serpent::Serpent ()
	{
		Ciphers.push_back (shared_ptr <Cipher> (new CipherSerpent()));

		SupportedModes.push_back (shared_ptr <EncryptionMode> (new EncryptionModeXTS ()));
	}

	// Serpent-AES
	SerpentAES::SerpentAES ()
	{
		Ciphers.push_back (shared_ptr <Cipher> (new CipherAES ()));
		Ciphers.push_back (shared_ptr <Cipher> (new CipherSerpent ()));

		SupportedModes.push_back (shared_ptr <EncryptionMode> (new EncryptionModeXTS ()));
	}

	// Twofish
	Twofish::Twofish ()
	{
		Ciphers.push_back (shared_ptr <Cipher> (new CipherTwofish()));

		SupportedModes.push_back (shared_ptr <EncryptionMode> (new EncryptionModeXTS ()));
	}

	// Twofish-Serpent
	TwofishSerpent::TwofishSerpent ()
	{
		Ciphers.push_back (shared_ptr <Cipher> (new CipherSerpent ()));
		Ciphers.push_back (shared_ptr <Cipher> (new CipherTwofish ()));

		SupportedModes.push_back (shared_ptr <EncryptionMode> (new EncryptionModeXTS ()));
	}

	// Serpent-Twofish-AES
	SerpentTwofishAES::SerpentTwofishAES ()
	{
		Ciphers.push_back (shared_ptr <Cipher> (new CipherAES ()));
		Ciphers.push_back (shared_ptr <Cipher> (new CipherTwofish ()));
		Ciphers.push_back (shared_ptr <Cipher> (new CipherSerpent ()));

		SupportedModes.push_back (shared_ptr <EncryptionMode> (new EncryptionModeXTS ()));
	}
}